radiology (rad) · radiology (rad) acrrm rural clinical guidelines - radiology (rad) - version...

Australian College of Rural & Remote Medicine

Rural Clinical Guidelines

Radiology (RAD)

ACRRM Rural Clinical Guidelines - Radiology (RAD) - Version January 2017 of 79

Australian College of Rural and Remote Medicine Rural Clinical Guidelines

ACRRM – January 2017

Note: As these guidelines have been specifically designed to be used on a mobile/smartphone device or as an online activity from your module enrolment you will find that there are numerous hyperlinks that you will not be able to access in this .pdf document.

As each discipline is a separate file it is suggested that you also download the ‘Alphabetical List’ of the guidelines to enable easy cross reference to guidelines in other disciplines.

For a list of all the abbreviations used in these guidelines download the ‘Abbreviations List’.

List of amendments in this update

No new amendments


End-user licence agreement for ACRRM Mobile Device Clinical Guidelines

1. Introduction(i) The terms and conditions stated here are in addition to the terms and conditions of the End-UserLicence Agreement for licensees of ACRRM software (Software Licence Agreement) which also applyto your use of these Mobile Device Rural Clinical Guidelines (Guidelines).2. Acknowledgement(i) The Guidelines were developed by the Australian College of Rural and Remote Medicine (ACRRM).3. Intellectual property rights(i) The Software Licence Agreement is a legal agreement between the customer and ACRRM whichsets out the terms and conditions of this legal agreement. By clicking on 'Accept' and downloading theGuidelines you have agreed to be bound by the terms and conditions of the Software LicenceAgreement.4. Permitted users(i) The Guidelines are for use only by health professionals who are currently enrolled in the ACRRMClinical Guidelines for PDA User Group on ACRRM's www.rrmeo.com website (Permitted Users). TheGuidelines may not be transmitted to or distributed to or used by other persons.5. Permitted uses(i) A Permitted User may download, store in a cache, display, print and copy the material in unalteredform only. The Guidelines may not be transmitted, distributed or used by any other person, orcommercialised without the prior written permission of ACRRM.6. Updating of Mobile Device Clinical Guidelines(i) The Guidelines may be updated from time to time. We may advise you by email from time to time ifnew versions of the Guidelines become available however you are responsible for checking whetheryou have the most recent version. The most recent version of the Guidelines is available on theACRRM Clinical Guidelines for PDA User Group webpage on www.rrmeo.com. We disclaim all liabilityarising from your failure to download updates of the Guidelines.7. Seek independent advice(i) The Guidelines are intended to aid Permitted Users in the management of their patients but do notprovide explanations as to the conditions or treatments outlined. There may be clinical or otherreasons for using different therapy. In all cases, users should understand the individual situation andexercise independent professional judgment when assessing therapy based on these Guidelines.Users should seek independent advice.(ii) The Guidelines do not include comprehensive drug information. Drug usage and doses shouldalways be checked prior to administering drugs to patients.(iii) Every effort has been made to ensure the validity and accuracy of the information in thisadaptation of the Guidelines however Permitted Users should at all times exercise good clinicaljudgment and seek professional advice where necessary. Treatment must be altered if not clinicallyappropriate.(iv) This adaptation of the Guidelines is presented as an information source only and provided solelyon the basis that users will be responsible for making their own assessment of the matters presentedherein. Users are advised to formally verify all relevant representations, statements and informationfrom appropriate advisers as it does not constitute professional advice and should not be relied uponas such.(v) To the extent permitted by law, ACRRM expressly disclaims any responsibility and all warranties,express or implied, and excludes liability for all loss (including consequential loss) whatsoever thatmay result in any way, directly or indirectly, from the use or reliance upon the Guidelines.

Process: For detailed referencing of the guideline sources, please see the acknowledgements page in the individual guidelines.


Table of Contents List of amendments in this update ............................................................................................................................................. 2 End-user licence agreement for ACRRM Mobile Device Clinical Guidelines ............................................................................ 3 ACKNOWLEDGEMENTS ................................................................................................................................................ 5 ACUTE CHEST TRAUMA ................................................................................................................................................ 6 BASICS OF RADIOLOGY ................................................................................................................................................ 7 CHEST RADIOLOGY ........................................................................................................................................................ 8 COMMON ABDOMINAL PATHOLOGIES .................................................................................................................. 9 COMMON BONY ABNORMALITIES ......................................................................................................................... 10 COMMON FRACTURES ................................................................................................................................................ 11 COMMON SKULL AND FACIAL BONE PATHOLOGIES ................................................................................... 12 CT HEAD SCAN ................................................................................................................................................................ 13 CT SCANS INDICATIONS ............................................................................................................................................. 28 FRACTURE, DISLOCATION, SUBLUXATION OR EPIPHYSEAL INJURIES ............................................. 32 IMAGING MODALITIES AND COMMON PATHOLOGIES FOR THE RENAL SYSTEM ......................... 33 JOINT CONDITIONS ....................................................................................................................................................... 34 PATHOLOGICAL CONDITIONS DETECTED ON CHEST RADIOLOGY...................................................... 35 PELVIS RADIOLOGY ...................................................................................................................................................... 36 PROSTHETIC APPEARANCES .................................................................................................................................. 37 RADIATION PROTECTION OF PATIENTS ............................................................................................................. 38 SKELETAL RADIOLOGY ............................................................................................................................................... 45 SKULL RADIOLOGY ....................................................................................................................................................... 46 SPINAL RADIOLOGY...................................................................................................................................................... 48 SPINAL SYSTEM INCLUDING COMMON PATHOLOGIES .............................................................................. 50 USEFUL RADIOLOGY RESOURCES ....................................................................................................................... 51 X-RAYS - SKULL .............................................................................................................................................................. 53 X-RAYS - SPINAL ............................................................................................................................................................. 63


RADIOLOGY

ACKNOWLEDGEMENTS

The x-ray images and some of the text are presented here with kind permission from the World Health Organisation “Radiographic Interpretation for General Practice” Palmer P E, Cockshott, W P, Hededus V and Samuel E (1985) Reprinted 1998.

References: - ‘Advanced Paediatric Life Support’ APLS, BMJ- Effective Choices for Diagnostic Imaging in Clinical Practice (1990). Report of a WHO Scientific Group.Technical Report Series 795 (available from Hunter Publications, Melbourne).- Lau L and James P (Eds) (1997), Imaging Guidelines. 3rd Edition. The Royal Australasian College ofRadiologists. Australia- Palmer P.E.S., Cockshott W.P., Hegedus V, Samuel E (1985) Manual of Radiographic Interpretation for GeneralPractitioners. World Health Organisation, Geneva: Reprinted 1998)- Richardson, ML Radiology Review for Primary Care Practitioners.

Reviewers: Dr Anthony Block, SMO, Atherton Hospital Jim Barton, Radiologist, Atherton Hospital Dr Dorcas Heap, GP, Atherton

ACRRM Clinical Guidelines Version January 2017 (*Expires January 2018 - check ACRRM website for latest version)


RADIOLOGY

ACUTE CHEST TRAUMA Damage to intrathoracic contents may occur with both open and closed chest injuries. The diagnosis of a tension pneumothorax should be made clinically and treatment started without waiting for x-ray examinations. However, chest x-rays are useful for management and to exclude a non-tension pneumothorax or intrapleural or pulmonary bleeding.

Pneumothorax (may need decompression) (i) Look for the edge of the collapsed lung (where the lung markings stop). A fold of skin can look like a pneumothorax, especially in children or the elderly. Also beware 'companion' shadow under upper ribs (normal). Confirm by clinical examination

(ii) There may be mediastinal and tracheal shift AWAY from the injured side (expiratory films demonstrate this clearly)

(iii) A supine film may appear normal, even when there is a small pneumothorax Subcutaneous emphysema. Air in the soft tissues of the chest wall may spread across the chest, axilla and neck, and if there is a large quantity it may hide an underlying pneumothorax. - check to make sure there is no shift of the trachea and mediastinum; - shift can only be due to air inside the chest (Palmer et al 1985, p 36)



RADIOLOGY

BASICS OF RADIOLOGY These online modules were developed by Dr Tony Lamont (Director of Radiology at Townsville Base Hospital).

The aim of the series is to teach some simple radiological principles and to show how they can be used to reach a diagnosis by a process of logic.

The modules in the series are: Basics of Radiology: Module 1: Physics and Optics Module 2: How to Read a Normal Chest X-Ray Module 3: Collapses & Consolidations Module 4: Diffuse Lung Disease

- to enrol in these modules go to RRMEO: https://www.rrmeo.com - Educational Inventory / RRMEO Modules - and scroll down to the module name and click on 'enrol'


https://www.rrmeo.com/


RADIOLOGY

CHEST RADIOLOGY Follow a systematic method in inspecting the chest radiograph Ensure patient details and date correct

(i) Check that the film is correctly centred, and is taken in full inspiration. A film taken in expiration can cause confusion; it may simulate disease e.g. pulmonary congestion, cardiomegaly, or a wide mediastinum; - exclude shadows due to hair, clothing or skin lesions.

(ii) Check that the exposure is correct (a finger held behind the “black area” of the film, or disc spaces behind the heart, should be just visible when correct density has been achieved). An underexposed (pale) film must be interpreted with caution; the lung appearance may suggest pulmonary oedema or consolidation. Over exposure (a black film) may suggest emphysema - check that the bony skeleton (ribs, clavicles, scapula, etc.) is normal - check that the diaphragm is normal in position; the right side of the diaphragm is usually 2.5 cm higher than the left (identified in the lateral view by the gas bubble in the stomach or colon beneath it) - check the superior mediastinum for widening, or the presence of abnormal masses, and identify the trachea - check the heart and great vessels for abnormalities. The cardiac diameter in adults (erect films) should be less than half the width of the chest in FULL inspiration PA film - all the markings in normal lungs are vascular. Check that they are normal in size and pattern -- the hilar shadows should show individual vessels representing the pulmonary arteries and large veins. It may be difficult to see other pulmonary veins. The left hilum is normally higher than the right -- remember that the pulmonary and cardiac systems are intimately related and that pulmonary changes (e.g. oedema) may be secondary to cardiac changes (Palmer et al 1985, p 29)



RADIOLOGY

COMMON ABDOMINAL PATHOLOGIES - intestinal obstruction: small bowel, large bowel - ileus - normal bowel patterns - faecal loading - pseudo obstruction - perforation of the gut - foreign bodies - abdominal calcifications (search pattern and differential diagnosis) - cholelithiasis - renal calculi - ureteric calculi - bladder calculi - lymph node calcification - phleboliths - pelvis (uterine fibroids, dermoid cysts) - calculi in the prostate - vascular calcification



RADIOLOGY

COMMON BONY ABNORMALITIES - infection (osteomyelitis) - inflammation - degenerative disease (osteoporosis) - metabolic disease - inherited abnormalities: osteogenesis, imperfect, dwarfism - benign lesions - neoplasia injury: multiple myeloma, primary bone tumours, bony metastases etc. - Paget’s disease - osteomalacia / rickets - bone cysts



RADIOLOGY

COMMON FRACTURES - shoulder girdle: clavicle, acromioclavicular joint, scapula - upper limb: ulna, humerus, radius, wrist, forearm, scaphoid - elbow, hand - ribs - pelvic girdle: hip, sacrum, coccyx - lower limb: femur, tibia, fibula knee, ankle, foot

(see - ToC / Musculoskeletal)



RADIOLOGY

COMMON SKULL AND FACIAL BONE PATHOLOGIES - depressed head fracture - penetrating head injury - facial trauma - lytic defects in skull - dense areas in skull - salivary calculus - orbit injury

(see - Skull radiology)



RADIOLOGY

CT HEAD SCAN An Emergency Medicine approach to interpretation of CT Head scans

NOTE: All images in this guideline can be enlarged by clicking or tapping on them

Introduction Common clinical indications CT basics Systematic Approach

Introduction - most commonly ordered CT imaging in ED - important investigative tool in traumatic and non-traumatic intracranial emergencies

Top

Common clinical indications - headache - altered mental status - focal neurological deficit - seizure - trauma

Clinical treatment decisions in some conditions need to be made in timely fashion Delays in interpretation could adversely affect patient outcome Basic interpretation skills essential to Emergency Physicians

Top

CT basics


- X-rays attenuated differentially by tissues of differing density (attenuation coefficient) - assigned gray scale value & presented as pixel on image


Windowing - CT able to differentiate > 2000 numbers - human eye can only differentiate ~ 30 shades of gray Windowing: allows focus on certain tissues of interest (assigned full range of blacks and whites) - subtle differences in tissue densities can be maximized


Top

Systematic Approach

ABCS: A - anatomy, asymmetry & artifacts - air-filled spaces B - bones - blood - brain parenchyma C - CSF spaces S - subcutaneous tissue

A: Anatomy Asymmetry Artifacts Air-filled spaces

(i) Anatomy Examine every axial image from top to bottom, then back up to top

( A) (ii) Asymmetry Compare left & right side of cranium Note displacement of brain structures causing midline shift (mass effect) - haemorrhage, tumour, oedema, CSF obstruction Magnitude of shift correlates with prognosis

( A)

(iii) Artifacts Physics based artifacts - beam hardening artifact - partial volume artifact Patient based artifacts - motion artifact - metallic artifact


Motion Artefact:

( A)

Air-filled spaces Maxillary sinus Frontal sinus Ethmoid sinus Sphenoid sinus Mastoid air cells Middle ear cavity Bone windows Normal air-filled space : black (-1000HU) Look for - opacification - air-fluid level In the setting of trauma, opacification indicates bleeding, indirect evidence of fracture


( ABCS)

B: Bones Blood Brain parenchyma

(i) Bones Bone windows Look for - defects in cortex of bone - pneumocephalus Examine skull, orbits - compare contralateral side Suture - symmetrical, less straight, corticated edges Fracture - look for secondary signs (opacification of adjacent air spaces, air-fluid level, pneumocephalus)

Intracranial air (pneumocephalus) - # skull - # airspace wall - previous surgical intervention


( B)

(ii) Blood Acute haemorrhage appears hyperdense (50-100HU) As blood / globin breaks down - lose hyperdense appearance Isodense in 1-2 weeks Hypodense in 2-3 weeks

Epidural haematoma (EDH) Subdural haematoma (SDH) Intraparenchymal haematoma Subarachnoid haemorrhage (SAH)

Epidural haematoma (EDH) - appears white to gray on brain window - biconvex shape - usually in temporal region - does not cross suture line - swirl sign = active bleeding (heterogenous appearance) - neurosurgical emergency - may cause mass effect, herniation

Subdural haematoma (SDH) - appearance depends on whether acute or chronic - crescent shape


- located peripheral to brain or interhemispheric - may cross suture line - may cause mass effect, herniation


Intraparenchymal haematoma - traumatic or spontaneous (e.g. hypertensive bleed) - vary from punctate to large - may lead to mass effect - distinguish from calcification


Subarachnoid haemorrhage (SAH) - appears white (hyperattenuating) on brain window: diffuse - located in subarachnoid space - sulci - fissures - cisterns - suprasellar cistern ('star') - 'Circle of Willis' - quadrigeminal plate cistern ('smiley face') - ventricles (reflux of blood into 4th ventricle) - may be accompanied by evidence of hydrocephalus, increased ICP - temporal horns of lateral ventricles - infundibulum of 3rd ventricle


( B)

(iii) Brain parenchyma Gray matter White matter Gray-white differentiation Hypo / hyper-densities Look for: - masses - differences in attenuation - asymmetry


Ischaemic stroke - initially normal / very subtle CT evidence - large, early ischaemic changes on CT - contraindication for thrombolysis - complemented by other imaging modalities (CTA, CTPS, MRI) Goals : - exclude intracranial bleed - exclude 'stroke mimic' - identify salvageable ischaemic brain

Ischaemic stroke CT findings: Loss of gray-white differentiation - insular ribbon sign - cortical sulcal effacement Hypoattenuation - follows vascular territory


Hyperdense MCA sign - thrombosed MCA (non contrast CT)


Cerebral oedema Loss of CSF containing spaces - sulci effacement - ventricular effacement (slit-like) - cistern effacement Loss of gray-white differentiation Midline shift Significance - increased ICP - cerebral ischaemia 20 decreased CPP

( B)

( ABCS)

C: (i) CSF spaces Ventricles - basal cisterns - cortical sulci & fissures Look for: - acute haemorrhage - mass effect / increased ICP - hydrocephalus


( ABCS)

S: (i) Subcutaneous tissue Scalp swelling - marker for acute injury

( ABCS)

Top

Reference: A presentation by Dr Alan Furniss, Atherton Hospital and also recognition of presentation by: - Dr Herman Chua, Emergency Medicine Consultant, Lyell McEwin Health Service



RADIOLOGY

CT SCANS INDICATIONS CT (computerized tomography) or CAT (computerized axial tomography) scans

Quick Referral Guide Indications

QUICK REFERRAL GUIDE Abdomen Chest Brain Paediatric

CT ABDOMEN

(I) Non - Contrast Renal Colic Adrenal Tumours Hernias Patients with IV contrast contra-indications Patients with renal impairment (ie. eGFR < 45, Creatinine > 120)

(ii) Contrast Haemangiomas Appendicitis Trauma Tumours Abscesses Vascular Abnormalities (e.g. Aneurysms, AVM’s) Non-specific Abdominal Pain Lymphoma Diverticulitis Bowel Obstruction

CT CHEST

(I) Non - Contrast High Resolution CT - HRCT (Lung Parenchyma only) Patients with IV contrast contra-indications Patients with renal impairment (ie. eGFR < 45, Creatinine > 120)

(ii) Contrast Trauma Tumours Abscesses Vascular Abnormalities Oesophageal Ca

CT BRAIN


(i) Non - Contrast Screening Headaches Organic Screen Psychiatric History

(ii) Non - Contrast Investigative Trauma Strokes (CVA/TIA) Pre-lumbar puncture scan for ? meningitis/encephalitis Intracerebral Bleeds Subarachnoid Haemorrhage (SAH) Epilepsy Follow-up Mastoids / IAM’s Syncope

(iii) Contrast Seizures (first presentation) Tumours Abscesses Vascular Abnormalities Headaches with focal signs Pituitary Fossa (MRI preferable) CP angle pathology (MRI preferable) Orbits (tumours, infection, proptosis)

CT PAEDIATRIC PATIENTS

Aim to minimize radiation exposure. Always follow the ALARA (As Low As Reasonably Achievable) principle. Remember - the best way to reduce radiation exposure is to not use ionising radiation at all. Give due consideration to alternative tests eg. Ultrasound or MRI where appropriate. Try to scan young babies when they are asleep. Ask parents sleep deprive the baby and to bring along a bottle, dummy or favourite toy.

Top

INDICATIONS CT Abdomen CT Brain CT Chest

CT ABDOMEN - INDICATIONS

(i) Non IV Contrast Scans Only Renal colic Adrenal tumours (unless directed by Radiologist) Patients where IV contrast is contra-indicated i.e. known contrast allergy - renal impairment (eGFR <45 CR 140 or above)

(ii) IV Contrast (Arterial) Pancreas study as per protocol.(helpful to give cup of water prior to scan) Haemangioma check with Radiologist for phases (iii) IV Contrast Scans (Portal Venous) Appendicitis Trauma Tumours (Primary and Metastatic)


Abscess or Masses Vascular abnormalities e.g. AVM’s, Aneurysms Non-specific abdominal pain Lymphoma Diverticulitis Bowel Obstruction Prostate

(iv) IV Contrast Dose *Always check for Contrast allergy! Adults: 75 – 100 mls Ultravist 370 (Pressure injected) Children: 2mls per Kilo of body weight (hand injected Ultravist 300)

(v) Oral Contrast All patients for routine Abdominal CT should be given water, especially when looking for lymphadenopathy or intra-abdominal collections. Ioscan can be given on individual basis. Consult with the Radiologist or the referring doctor before giving oral contrast to patients with acute trauma.

***DO NOT GIVE ORAL CONTRAST TO PATIENTS HAVING SPECIFICALLY VASCULAR STUDIES e.g. Aortic stent planning, Renal artery studies, CT Cholangiogram's etc.

CT BRAIN - INDICATIONS

(i) Non-Contrast Screening (Axial Protocol) Headaches Organic screen Psychiatric history

(ii) Non-Contrast Investigative (Helical Protocol) Trauma Strokes (CVA) / TIA Pre-lumbar puncture scans for ? meningitis /encephalitis Intracerebral bleeds SDH Subarachnoid haemorrhage SAH Epilepsy F/up Ataxia (unsteady gait) Mastoids bone windows (cholesteatoma / mastoiditis) Syncope (fainting)

(iii) Contrast Scans (Always do non-contrast scans first.) Epilepsy (Pre-Post Cont. if first presentation) Tumours (Primary and Metastatic)/SOL Abscess (Pre and Post Cont.) Vascular abnormalities e.g. AVM’s, Aneurysms Post Ictal (seizures) Headaches with focal signs IAM’S Post Contrast only (acoustic neuromas/tinnitus/vertigo) Pit Fossa (contrast though pit and then full brain) Orbits (tumours, infection, proptosis) Nystagmus (involuntary eye movement-focal neuropathy) Pre - Post

(iv) Contrast Dose *Always check for Contrast allergy! Adults: 50 mls Ultravist 370 (hand injected) Children: 1.5 to 2 mls per Kilo of body weight (hand-injected Ultravist 300)

HINT: When scanning for tumours, infection or other more unusual conditions such as MS plaques or Nocardia etc., it is preferable to let the contrast soak for a few minutes before scanning. - MRI is the test of choice for MS.

CT CHEST - INDICATIONS


( i) Non IV Contrast Scans Only Patients where IV contrast is contra-indicated ie. Known contrast allergy - Renal impairment High Resolution CT (Lung parenchyma only) - Inspiration and Expiration - Prone on request

(ii) IV Contrast Scans Trauma Tumours (Primary and Metastatic) Abscess Vascular abnormalities e.g. Aneurysms (use Thoracic Angio protocol) Oesophageal Ca (can be helpful to give mouthful of Gastrogafin prior to scan) (iii) IV Contrast Dose *Always check for Contrast allergy! Adults: 75 – 100 mls Ultravist 370 (Pressure injected) Children: 1.5 to 2 mls per Kilo of body weight (hand injected Ultravist 300)

Top

Reference: Compiled by: Sheila Ryan - Senior CT Radiographer, Case Base Hospital Dr Steve Bickford - Director of Medical Imaging, Case Base Hospital has kindly given permission for ACRRM to use these Referral and Indications guides for your reference only. - he advises that their aim in compiling these guides is to improve the results of reporting processes to GP's which has been quite labour-intensive to date and therefore not as reliable as they would like - hence the development of these 'Quick Referral Guides'.



RADIOLOGY

FRACTURE, DISLOCATION, SUBLUXATION OR EPIPHYSEAL INJURIES - displaced / non-displaced - simple / comminuted - presence of foreign bodies - associated soft tissue injury: localised oedema, surgical emphysema, gas gangrene - joint or growth plate involvement - special risks or complications - precautions (particularly 'readily missed') - slipped femoral epiphysis

(see - ToC / Musculoskeletal)



RADIOLOGY

IMAGING MODALITIES AND COMMON PATHOLOGIES FOR THE RENAL SYSTEM - KUB (kidneys, ureters and bladder) intravenous pyelography - retrograde cystography - retrograde urethrography - retrograde micturating urethrography - missing kidney - variations in anatomy - calyceal patterns - large kidney / small kidney / ureters / bladder - prostatic calculi



RADIOLOGY

JOINT CONDITIONS - osteoarthritis - rheumatoid arthritis - gout - ankylosing spondylitis - Perthes’ disease - arthritis (see Richardson’s rules of arthritis - in online textbook)



RADIOLOGY

PATHOLOGICAL CONDITIONS DETECTED ON CHEST RADIOLOGY - pain in chest / acute chest trauma - closed chest injuries / penetrating chest injuries - inhaled foreign body - pleural effusions / loculated effusion - pneumothorax / hydropneumothorax - pulmonary collapse / atelectasis - widened mediastinum (aortic aneurysm appearance, mediastinal pathology or tumours e.g. thymoma) - densities in the lungs - emphysema - bronchitis / asthma / COPD / pulmonary contusion - pneumonia (inflammatory consolidation) - staphylococcal pneumonia - bacterial pulmonary (lung) abscess / amoebic lung abscess - acute tuberculous cavitation - pulmonary tuberculosis with cavity formation - enlarged lymph nodes (abnormal hilar patterns such as sarcoidosis, bronchial carcinoma etc.) - hydatid cysts - primary lung cancer / secondary (metastatic) lung cancer - mycetoma (fungus ball) - diffuse increase in lung pattern - pneumoconiosis (industrial disease) - pulmonary embolism/infarction - cardiac failure such as: Kerley “B” lines, bat's wing shadowing, left ventricular hypertrophy, atrial enlargement, obliteration of costophrenic angles, altered upper / lower lobe perfusion - enlarged heart - pericardial effusion and cardiomyopathy - pulmonary oedema



RADIOLOGY

PELVIS RADIOLOGY Most pelvic fractures are easy to see, but remember that they are almost always multiple. The pelvis is a bony ring interrupted at the sacro-iliac joints and the pubic symphysis. Trauma to the ring almost always causes two or more fractures. If you can only see one bony injury, look carefully at the joints and ligaments to make sure that they have not been disrupted (Palmer et al 1985, p 106)



RADIOLOGY

PROSTHETIC APPEARANCES - hip - knee replacements - spinal fusions



RADIOLOGY

RADIATION PROTECTION OF PATIENTS See also: Radiation and the Fetus in Obstetrics & Women's Health

Aims Radiation in imaging (i) Doses (ii) Cancer risk Patient Protection Notes 1. Radiation Doses 2. Typical Fetal Doses and Risks of Childhood Cancer

Other Resources How imaging modalities work Useful information Useful organisations

AIMS

MEDICAL IMAGING is largest contributor to population radiation dose

ENSURE - radiation use justified - understanding of risks / benefits - See: (ii) Ask - (7 questions for the Referrer)

BACKGROUND RADIATION - Australia averages 1.5 mSv per annum (worldwide average 2.4 mSv per annum)

MEDICAL RADIATION - av 2.0 mSv in Australia (> background) BERT = Background Equivalent Radiation Time This unit quantifies radiation exposure in terms of the time it normally takes to receive the same radiation dose from background sources.

EFFECTS OF RADIATION For the purposes of radiation protection it is prudent to assume: - Cancer: 5% per Sv (1 / 20,000per mSv) - Genetic: 0.25% per Sv (1 / 400,000 per mSv) - Tissue Damage: predictable at high doses - Death: (5,000 mSv) N.B. approx. 1000 additional Australians may die each year from X-ray induced cancer

(top)

RADIATION IN IMAGING Doses Cancer risk


(i) DOSES See Notes 1. Radiation Doses for: - X-ray doses - CT doses - Nuclear medicine doses

N.B. MRI and USS do not use radiation - imaging of choice for children / pregnancy

( Radiation in Imaging)

(ii) CANCER RISK - Lifetime Higher for youngest (longer life expectancy)

- For 30 year old Adult - Pregnant Patients

For 30 year old Adult:

Typical doses and associated risk of cancer Procedure Effective Dose (mSv) Lifetime Risk of Death from Cancer* X-rays Chest (PA) 0.02 1 in 1,000,000 Abdomen 0.7 3.5 in 100,000 Pelvis 0.6 3 in 100,000 CT scans Head 2 1 in 10,000 Abdomen 8 4 in 10,000 Angiography Various 5 – 10 2.5–5 in 10,000 Nuclear Medicine Various 2 – 10 1–5 in 10,000 * For a 30 year old adult Source: Australian Radiation Protection and Nuclear Safety Agency (ARPANSA)

PREGNANT PATIENTS - Fetal exposure - Fetal risks - Principles

Fetal exposure - only abdo / pelvis x-rays contribute to fetal dose (i.e. imaging of limbs, head, chest carry negligible / low fetal dose) - significant effects only if fetal exposure of 100mSv (~65 times BERT) - see Notes 2.

Fetal risks Congenital malformations - highest risk weeks 4-12 (organogenesis) - organogenesis does not commence until after 3rd week of pregnancy Neurodevelopmental delay - esp. 8-15 weeks pregnancy (but CNS sensitive <25 weeks) Death - only if >100mSv i.e. multiple procedures


Principles - use USS or MRI if possible - unless emergency, schedule x-rays for first 10 days after a normal period - seek specialist advice for Group 3 tests - see Notes 2.

( Radiation in Imaging)

(top)

PATIENT PROTECTION

(i) Imaging Cycle (click on image to enlarge)

(ii) Ask - (7 questions for the Referrer)

Before requesting an imaging investigation, the referring doctor must consider the following questions:

Have I taken a history, performed a physical examination and come to a provisional diagnosis?

Is imaging required? - Will it: Change my diagnosis? Affect the patient’s management? Do more harm than good?

Are the investigations needed now? - Avoid undertaking investigations too early. Sometimes clinicians order tests before the condition has progressed or before the results could influence treatment.

Am I duplicating recent tests? - Previous relevant images or reports may avoid repeating the investigation.

If imaging is indicated, what is the best option? - Imaging techniques undergo rapid change; it may be useful to discuss with a radiologist the alternatives available that minimise or do not use ionising radiation before ordering an imaging procedure.


Have I adequately communicated the risks and benefits of the imaging procedure to my patients/parents, before ordering the investigation?

If imaging is required, have I defined the clinical problem adequately on the request form? - The best patient outcomes occur when referrers provide appropriate information, allowing the imaging team to focus on the clinical problem and write a targeted report.

- see Patient Information Form

(top)

NOTES 1. Radiation Doses 2. Typical Fetal Doses and Risks of Childhood Cancer

(top)

1. Radiation Doses - X-ray Doses - CT Doses - Nuclear Medicine Doses

(i) X-ray Doses (click on images to enlarge)

(ii) CT Doses

(iii) Nuclear Medicine Doses

( Notes)

2. Typical Fetal Doses and Risks of Childhood Cancer

Examination type Typical Fetal dose (mGy)

Risk of childhood cancer per examination


Group O: - Ultrasound - Magnetic Resonance Imaging (MRI)

0 0

Group 1: - X-ray skull - X-ray chest - X-ray thoracic spine - Mammogram - Head or neck CT

0.001-0.01 <1 in 1 000 000

Group 1: - CT pulmonary angiogram - Lung ventilation scan

0.01-0.1 1 in 1,000,000 to 1 in 100,000

Group 2: - X-ray of abdomen, pelvis or hip or barium meal - CT scan of the chest and upper abdomen - Nuclear Medicine scans using technetium-99m including thyroid scan, lung perfusion scan, renal scan (DMSA, MAG3) or white cell scan

0.1-1.0 1 in 100,000 to 1 in 10,000

Group 3: - Lumbar spine x-ray - Barium enema - IVP or urogram - CT abdomen or lumbar spine - Nuclear scans using technetium-99m: bone scan, cardiac pool scan, myocardial scan, renal scan - Thallium-201 myocardial scan

1.0-10 1 in 10,000 to 1 in 1,000

Group 3: - CT of pelvis or pelvis plus abdomen - PET-CT - Technetium-99m myocardial SPECT (rest - exercise protocol)

10-50 1 in 1,000 to 1 in 200

Note: Natural Childhood risk of cancer is 1 in 500. Advice from the UK Health Protection Agency, the Royal College of Radiologists and the College of Radiographers. Source: O & G Magazine Vol 17 No 1 Autumn 2015

( Notes)

(top)

Other Resources How imaging modalities work Useful information Useful organisations

How imaging modalities work

The following are links to typically 60 second videos describing how the common imaging modalities work.

How does a CT scan work? https://www.youtube.com/watch?v=81PeTqmtzjk

How does a PET scan work? https://www.youtube.com/watch?v=GHLBcCv4rqk

How does a MRI work? https://www.youtube.com/watch?v=1CGzk-nV06g

What is medical ultrasound? https://www.youtube.com/watch?v=KwsvDQhOpe

https://www.youtube.com/watch?v=81PeTqmtzjk

https://www.youtube.com/watch?v=GHLBcCv4rqk

https://www.youtube.com/watch?v=1CGzk-nV06g

https://www.youtube.com/watch?v=KwsvDQhOpe


3D reconstruction imagery? https://www.youtube.com/watch?v=82jSftX-1C0

Useful information

Clinical Referral Guidelines http://www.imagingpathways.health.wa.gov.au/

Background radiation http://www.arpansa.gov.au/radiationprotection/Factsheets/is_ionising.cfm http://glossary.eea.europa.eu/terminology/concept_html?term=background%20radiation

Imaging modalities http://www.nlm.nih.gov/medlineplus/diagnosticimaging.html http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandprocedures/medicalimaging/medicalx-rays/default.htm

Risks and risk ratios http://www.australianprescriber.com/magazine/31/1/12/6

Communicating risks and benefits with patients http://www.imagewisely.org/imaging-modalities/computed-tomography/medical-physicists/articles/how-to-understand-and-communicate-radiation-risk

Glossary of nuclear terms http://www.ansto.gov.au/NuclearFacts/GlossaryOfNuclearTerms/index.htm

CT Scans and Children – Information for Referrers http://www.safetyandquality.gov.au/wp-content/uploads/2015/07/CT-scans-for-children-information-for-referrers.pdf

Useful organisations

Western Australia Diagnostic Imaging Pathways http://www.imagingpathways.health.wa.gov.au/

Royal Australian College of General Practitioners http://www.racgp.org.au/

Australian College of Rural and Remote Medicine https://www.acrrm.org.au/

Royal Australian and New Zealand College of Radiologists http://www.ranzcr.edu.au/

International Atomic Energy Agency - Radiation Protection of Patients https://rpop.iaea.org/RPoP/RPoP/Content/index.htm

Australian Institute of Radiography http://www.air.asn.au/

Choosing Wisely http://www.choosingwisely.org.au/

Australian Commission for Safety and Quality in Health Care http://www.safetyandquality.gov.au/

https://www.youtube.com/watch?v=82jSftX-1C0

http://www.imagingpathways.health.wa.gov.au/

http://www.arpansa.gov.au/radiationprotection/Factsheets/is_ionising.cfm

http://glossary.eea.europa.eu/terminology/concept_html?term=background%20radiation

http://www.nlm.nih.gov/medlineplus/diagnosticimaging.html

http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandprocedures/medicalimaging/medicalx-rays/default.htm

http://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandprocedures/medicalimaging/medicalx-rays/default.htm

http://www.australianprescriber.com/magazine/31/1/12/6

http://www.imagewisely.org/imaging-modalities/computed-tomography/medical-physicists/articles/how-to-understand-and-communicate-radiation-risk

http://www.imagewisely.org/imaging-modalities/computed-tomography/medical-physicists/articles/how-to-understand-and-communicate-radiation-risk

http://www.arpansa.gov.au/radiationprotection/Factsheets/is_ionising.cfm

http://www.safetyandquality.gov.au/wp-content/uploads/2015/07/CT-scans-for-children-information-for-referrers.pdf

http://www.safetyandquality.gov.au/wp-content/uploads/2015/07/CT-scans-for-children-information-for-referrers.pdf

http://www.imagingpathways.health.wa.gov.au/

http://www.racgp.org.au/

https://www.acrrm.org.au/

http://www.ranzcr.edu.au/

https://rpop.iaea.org/RPoP/RPoP/Content/index.htm

http://www.air.asn.au/

http://www.choosingwisely.org.au/

http://www.safetyandquality.gov.au/


Australian Radiation Protection and Nuclear Safety Agency http://www.arpansa.gov.au/radiationprotection/factsheets/is_PaediatricCT.cfm

Image Wisely http://www.imagewisely.org

(top)

References:

1. Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) - http://www.arpansa.gov.au/ 2. O & G Magazine Vol 17 No 1 Autumn 2015

(top)


http://www.arpansa.gov.au/radiationprotection/factsheets/is_PaediatricCT.cfm

http://www.imagewisely.org/

http://www.arpansa.gov.au/


RADIOLOGY

SKELETAL RADIOLOGY (i) Obtain two views as nearly as possible at right angles for ALL suspected fractures and dislocations, except in the pelvis where oblique projections may help. - sometimes more views may be needed e.g. the wrist, but look at the routine views first (ii) Make sure that the films always show the joint ABOVE and BELOW any suspected fracture of the forearm or leg, unless it is clinically obvious that the injury is only in the most distal part of the limb (even then the nearest joint must be included) (iii) Remember that TENDON or VASCULAR damage cannot be seen on routine x-rays (iv) When looking at an x-ray film, remember that just because you have seen one obvious injury, you MUST NOT stop looking, as there may be further fractures or other abnormal findings (Palmer et al 1985, p 86)

Useful General Concepts

Always correlate X-ray with clinical findings:

The Ring Bone Rule: The body contains quite a few of these. - if you see a fracture or dislocation in one of them, look for another.

Ring Bones and Equivalents: - Main pelvic ring - Obdurator ring of pelvis - Mandible and skull - Zygomatic arch - Ribs, sternum and spine - Each vertebra - Foramina transversaria in C-spine - Radius/ulnar - Tibia/fibula (ring bone equivalents)

Old Films are very valuable – - if possible obtain the patient’s previous films to use for comparison.

Ordering a different radiographic view. - if you can’t see what you need to see on the current x-ray, a different view may show it. (Richardson, ML Radiology Review for Primary Care Practitioners.



RADIOLOGY

SKULL RADIOLOGY CT scan has replaced X-ray skull usually if available If CT not available --> Indications for x-rays include:

Trauma Bleeding from the ears A local bulge (or dent) in the skull Persistent headache Earache Metastases or general disease Indications for skull radiograph

1. Trauma SEVERE head injury in adults, especially with prolonged loss of consciousness or when there is clinical evidence of a depressed fracture, is a clear indication for x-rays (i) Mild trauma: If the patient has not lost consciousness or has only been unconscious briefly, and if the clinical examination is normal, it is probable that skull x-rays will not alter your treatment. Clinical signs will be far more important (loss of consciousness, change in pulse or respiration, fits, double vision etc) (ii) Trauma in children: It is usually easy to detect a depressed fracture in a child by clinical examination and skull x-rays are then necessary to show the extent of the injury and the treatment needed. Mild head injury with normal clinical examination is not an indication for x-rays because it is unlikely that treatment will be altered

2. Bleeding from the ears OR Cerebrospinal fluid leaking from the ears or nose after trauma almost always means a fracture at the base of the skull. - this is very difficult to recognise on x-rays. - a lateral view taken with the patient lying supine may show blood in the sphenoid sinus or air within the skull

3. A local bulge (or dent) in the skull X-rays may help in the diagnosis provided the bulge is fixed on clinical examination, and not mobile (i.e. not only in the scalp). If the bulge is soft, an x-ray of that area will help to exclude an underlying skull defect (infection, tumour, etc.)

4. Persistent headache X-rays seldom provide much useful information unless there are clinical signs - e.g. neurological abnormality, raised intracranial pressure (optical signs), or blindness. A straight AP film may show pineal shift. If the patient is known to have a primary malignant tumour elsewhere, a lateral skull x-ray may help to show skull metastases

5. Earache Clinical examination is better than x-rays unless you are an expert on mastoid x-rays. Routine skull films are seldom helpful when mastoiditis is suspected

6. Metastases or general disease - such as Paget’s disease A lateral view of the skull may help in the diagnosis. Two views minimum:


- AP & Lat. OR - Lat. & Townes

Indications for skull radiograph: (CT if available) - Loss of consciousness or amnesia at any time - Neurological symptoms and signs - CSF or blood from nose/ear - Suspected penetrating injury or foreign body - Scalp bruising or swelling - Significant mechanism of injury - Children under 2 years of age with expansile skull sutures - Difficulty in assessing the patient - Non-mobile infants (the likelihood of abuse is higher) - Children in whom an adequate history is not available - Alcoholic intoxication (From ‘Advanced Paediatric Life Support’ APLS, BMJ.



RADIOLOGY

SPINAL RADIOLOGY See - SPINAL INJURIES - Cervical See - SPINAL INJURIES - Thoraco-lumbar

Patients with spinal trauma should be examined with great caution until a fracture or dislocation, especially an unstable one, is excluded. Patients suspected of fracture or dislocation are initially evaluated with a supine cross-table lateral film. This is frequently obtained as part of a “trauma” series. If a fracture or dislocation is found, then further views are undertaken with extreme care not to shift the patient’s neck, but rather position the x-ray tube and cassette appropriately for each view (Lau and James P 1997, p 158).

Cervical Trauma (Level 1) (Level 11 and Level 111 include computerised tomography, Myelography and MRI - but we are assuming rural doctors will not have access to these facilities) Radiographic examination is not indicated when the patient is alert, sober, cooperative and without neck pain or tenderness, even when there are significant other injuries. In other cases, radiography is indicated as below.

The procedure depends on the condition of the patient. Patients Cx spine should be fully immobilised until cleared. (i) Patient able to stand or sit. Anteroposterior, lateral and open-mouth views are required, with the patient in the erect position. When the clinical or radiographic findings are equivocal, add both oblique projections. The seventh cervical vertebra must be demonstrated, if necessary by conventional tomography if available (ii) Patient able to stand. Supine, horizontal-beam lateral, and 100

Cranial anteroposterior views are required. An open-mouth projection should be obtained if possible, but this is not necessary in children under 5 years (Effective Choices for Diagnostic Imaging in Clinical Practice (1990). Report of a WHO Scientific Group. Technical Report Series 795 (available from Hunter Publications, Melbourne).

Reading Spinal Films - Look at each part of the spine in the same way; the sequence is the same for the cervical, thoracic, and lumbar regions

AP View: Look at the alignment. At all levels the vertebrae should be in a straight line or only slight curved.

Lateral Projection: Look at the posterior part of the vertebral bodies. The curve should be smooth without any abrupt step or change in direction.

AP View: Next look at the shape of each vertebral body. This must be done very carefully. There are no “short cuts”. The transverse processes and the pedicles (the white oval) are visible. The spinous processes will vary slightly in shape and angulation.


Then look at the disc spaces. In the cervical and lumbar areas look for the paravertebral joints, which are not always easily seen.

Lateral projection Follow the same routine: (i) Look at EACH vertebral body. In each region of the spine they should be about the same size and shape. Also look at each intervertebral space. These should also be about the same width at each level. If the spaces seem to be narrowed, look carefully at the surrounding vertebral bodies for any change in shape or density. Then look at the density inside each vertebra very carefully. (Overlying bowel gas may resemble a lucency. Correlate with the AP view of the same vertebra). (ii) The normal spine has forward curvature in the cervical area, backward (kyphotic) curvature in the thoracic area, and forward (Lordotic) curvature in the Lumbar area. If any part of the spine is straight or has a reverse curvature, seek the cause.

Always Check Vertebral Alignment When looking at any part of the spine in the lateral view, check that there is a smooth continuous “line” along the posterior edges of the vertebral bodies. Check also the space between vertebrae, particularly for narrowing (Palmer et al 1985, p 146-147)



RADIOLOGY

SPINAL SYSTEM INCLUDING COMMON PATHOLOGIES - ageing - kyphoscoliosis - joint conditions as above - fractures (see - Fractures) - dislocations and subluxations (see - Dislocations - Other) - spinal trauma (see - Trauma - Spinal) - changes in vertebral density and outline without injury - pathological fractures - fractured pelvis recognition - metastatic lesions

(see - Spinal radiology)



RADIOLOGY

USEFUL RADIOLOGY RESOURCES Books: - ABC’s of Major Trauma – British Medical Journal (contains a lot of radiology). - ABC of Emergency Radiology: Ed David A Nicholson, Peter A Driscoll, BMJ Publishing Group. ISBN0727908324. - Accident and Emergency Radiology: A Survival Guide. Nigel Raby, Laurence Berman, Gerald de Lacey Saunders. Available in Australia from Harcourt Books. - Corne J (1998) Chest x-rays Made Easy, Churchill Livingstone, (available from Harcourt Books). - Effective Choices for Diagnostic Imaging in Clinical Practice (1990). Report of a WHO Scientific Group. Technical Report Series 795 (available from Hunter Publications, Melbourne, ($21.28 with GST). - Keats TE. Atlas of normal Roentgen variants that may simulate disease. Year Book, Chicago. - Lau L and James P (Eds) (1997), Imaging Guidelines. 3rd Edition. The Royal Australasian College of Radiologists. Australia. - Palmer P.E.S., Cockshott W.P., Hegedus V, Samuel E (1985) Manual of Radiographic Interpretation for General Practitioners. World Health Organisation, Geneva: Reprinted 1998. - Quality Assurance in diagnostic radiology. WHO Publication. 1982.

Journal Articles: - Espinosa J A, Nolan TW (2000) Reducing errors made by emergency physicians in interpreting radiographs: longitudinal study. BMJ; 320:737-740, 18 March. - Gotwald TF, Daniaux M, Stoeger A, Knapp R and zur Nedden D (2000). The value of the World Wide Web for tele-education in radiology. Journal of Telemedicine and Telecare. 6:27-30. (this article randomly selected some radiology websites and evaluated them for their educational quality). - Mak V (2000) Radiology on the Internet, Hospital Medicine, April Vol 61, No 4, p 291. (This one page article reviews some of the better radiology sites on the web). - Sanville, P, Nicholson DA, and Driscoll PA (1994) ABC of Emergency Radiology: The Knee. BMJ, 308:121-125 (8 January) Full text available form BMJ webpage http://www.bmj.com. - Tello R, Davison BD and Blickman JG (2000) The virtual course: delivery of live and recorded continuing medical education material over the Internet. Am J Roentgenol. Jun;174 (6):1519-21. - Touquet R, Driscoll P and Nicholson D (1995) Recent Advances: Teaching in accident and emergency medicine: 10 commandments of accident and emergency radiology. BMJ, 310:642-648 (11 March). Full text available form BMJ web page http://www.bmj.com.

Internet Sites: - http://www.acr.org American College of Radiology is an excellent site with a lot of good useful educational material. Has a selection of radiology educational CD-ROMs for sale. - http://www.rcrad.org.uk/enquiries/radiology/publications.html The Royal College of Radiologists (London). This site has a large number of radiology publications which can be bought, and lots of other useful educational material. - http://www.lib.uiowa.edu/hardin/md/rad.html (University of Iowa site). - http://www.guideline.gov/ This is the site of the US National Guideline Clearing House. It contains diagnostic imaging guidelines - http://www.drjones.com.au (South Australian Site, with a lot of useful links). - http://www.qdixray.com.au Good Qld Site. Qld Diagnostic Imaging. - http://www.qdixray.com.au/webpages.cfm?pagenumber=12 (Qld Diagnostic Imaging Updates ). - http://www.medmatrix.org - http://www.kfinder.com - http://www.intute.ac.uk/healthandlifesciences/medicine/ - http://radiologycme.stanford.edu/ On this site, you can buy radiology CME lectures online. - http://www.rad.washington.edu This University of Washington site has an online teaching file, with a large number of cases with question and answer segments, including 46 musculoskeletal cases, and 9 chest cases. - http://www.vh.org/Providers/ProviderDept/InfoByDept.Rad.html Virtual Hospital Site (University of Iowa) with good teaching cases and links to other sites. - http://www.vh.org/Providers/Lectures/icmrad/skeletal/01Trauma.html Basic Trauma Radiology Education

http://www.bmj.com/

http://www.bmj.com/

http://www.acr.org/

http://www.rcrad.org.uk/enquiries/radiology/publications.html

http://www.lib.uiowa.edu/hardin/md/rad.html

http://www.guideline.gov/

http://www.drjones.com.au/

http://www.qdixray.com.au/

http://www.qdixray.com.au/webpages.cfm?pagenumber=12

http://www.medmatrix.org/

http://www.kfinder.com/

http://www.intute.ac.uk/healthandlifesciences/medicine/

http://radiologycme.stanford.edu/

http://www.rad.washington.edu/

http://www.vh.org/Providers/ProviderDept/InfoByDept.Rad.html

http://www.vh.org/Providers/Lectures/icmrad/skeletal/01Trauma.html


- http://www.vh.org/Providers/Lectures/icmrad/chest/03FilmAnalysis.html Chest Radiology - http://www.radiologyresource.org/content/bone_radiography.htm Information about Radiology mainly aimed at the general public. - http://www.radiographersreporting.com/ Good images of trauma radiography and reports. The author is the Superintendent Radiographer for Trauma and Orthopaedics at the Royal Sussex County Hospital in Brighton, Sussex, UK. - http://www.xray2000.co.uk/ This site has online tutorials, useful links and online learning.


http://www.vh.org/Providers/Lectures/icmrad/chest/03FilmAnalysis.html

http://www.radiologyresource.org/content/bone_radiography.htm

http://www.radiographersreporting.com/

http://www.xray2000.co.uk/


RADIOLOGY

X-RAYS - SKULL 1. Normal Skull 2. Skull Fractures

Note:

indicates refer to image below

indicates refer to image above

1. NORMAL SKULL (i) Lateral Skull (ii) Frontal (AP) Projection

(i) Lateral Skull Search Pattern:

Look at the shape of the whole skull. Is there any area which bulges outwards or is dented inwards?

Look at the density of the skull. There are always areas which are less dense at the front and the back. The base of the skull is white because of the petrous bone.


Follow the lines of the inner and outer tables all around the skull vault.

Identify the vessels; arteries are usually fairly regular and veins irregular. Both divide into branches which are smaller than the main channel. Vessels have white cortical margins (fractures do not). Veins lead to irregular venous lakes. Vessels, especially veins, can be very large and still be normal. The pattern varies from patient to patient.

When possible look at the teeth; in children there will be a translucent (dark) area around the roots while they are growing. In adults such an area usually means an abscess or, if there are several little holes, osteomyelitis or occasionally lymphoma.

The dense white shadows are dental fillings.


Then identify the pituitary fossa on the base of the skull in front of the white petrous bone. Below it is the translucent (dark) sphenoid sinus.

see above - anterior clinoids, posterior clinoids, pituitary fossa (sella), sphenoid sinus, floor of fossa

a. petrous bone

b. sphenoid sinus


(ii) Frontal (AP) Projection Quality control:

The orbits must be symmetrical, with the nasal bones in the centre of the film. The mandible should appear equal on both sides. The dense white petrous bones should be across the lower part of the orbits.

see above 1. temporo-parietal suture 2. frontal sinus 3. supra-orbital ridge 4. orbit 5. sphenoid sinus 6. ethmoid sinus 7. infra-orbital ridge 8. nasal septum 9. maxillary antrum

Search pattern: Look at the shape of the skull. Is there any part which bulges outwards or is dented inwards? Follow the white line of the cortex from one side over the top of the skull to the other side. Is there any area of different density? (The lateral aspects along the temporal bones always seem more translucent.) Identify the supra-orbital ridges and the infra-orbital margins.

Look for the frontal sinus. This is often asymmetrical in shape and uneven in density. The ethmoid and sphenoid sinuses are on either side of the nose. The maxillary antra, below the orbit, should be of equal translucency.

2. SKULL FRACTURES

(i) Linear fractures (ii) Semi-axial (Towne's) projection (iii) Fractured mandible


Fractures are seen as black lines, but where there is an overlap of the fragments the lines will be white.

(i) Linear fractures These must be differentiated from vessels. Fractures vary in calibre, they seldom branch, have no white

margin, and may be anywhere. Vessels must be in the correct anatomical direction, have white margins and branch to smaller vessels. The patient's clinical condition and soft-tissue swelling are very helpful indicators.


A branching vessel with white margins

(ii) Semi-axial (Towne's) projection When the posterior part of the skull, the occiput, is injured you must have this Towne's projection (left)


Do not forget that the shadow of the ear (the pinna) can look like a fracture or intracerebral calcification.

If you suspect a fracture at the base of the skull, take a cross-table lateral view with the head in the position shown above. You may see fluid (blood or cerebrospinal fluid) in the sphenoid sinus. Unless the patient has severe sinusitis, this can only be due to a fracture at the base of the skull.


& a. Fluid in the sphenoid sinus

Fractures of the nasal sinuses may allow air to escape into the orbits, especially when the patient blows his nose. This causes orbital emphysema, and the air shows as a black line across the roof of the orbit if the X-ray is taken with the patient sitting up.


a. A small amount of air in the right orbit. There is more in the left orbit.

b. Do not mistake the gap between the eyelids for air. This will be in the middle of the orbit; air will be at the top.

c. Air in the left orbit following facial trauma. Infection may follow this type of injury. It is seldom possible to recognize the actual fracture, but if there is air in the orbit, there must be an injury.

(iii) Fractured mandible

Take sinus views and a PA view of the skull. Add obliques if necessary. Mandibular fractures are often bilateral; look carefully for the second injury and check clinically. The parts of the mandible near the temporo-mandibular joint and at the angle are where fractures are often missed radiologically.


RADIOLOGY

X-RAYS - SPINAL 1. Search Pattern 2. Normal Cervical Spine 3. Normal Thoracic Spine 4. Normal Lumbar Spine 5. Aging 6. Spinal Trauma

Note:

indicates refer to image below

indicates refer to image above

1. SEARCH PATTERN Look at each part of the spine in the same way; the sequence is the same for the cervical, thoracic, and lumbar regions.

AP view

Look at the alignment. At all levels the vertebrae should be in a straight line or only slightly curved.

Lateral projection

Look at the posterior part of the vertebral bodies. The curve should be smooth without any abrupt step or change in direction.


AP view

Next look at the shape of each vertebral body. This must be done very carefully. There are no "short-cuts". The transverse processes and the pedicles (the white oval) are visible - (see 1. in images below).

The spinous processes - (see 2. in the images above) - will vary slightly in shape and angulation. Then look at the disc spaces. In the cervical and lumbar areas look for the paravertebral joints, which are not always easily seen.

Lateral projection

Follow the same routine: look at EACH vertebral body. In each region of the spine they should be about the same size and shape. Also look at each intervertebral space. These should also be about the same width at each level. If the spaces seem to be narrowed, look carefully at the surrounding vertebral bodies for any change in


shape or density. Then look at the density inside each vertebra very carefully. (Overlying bowel gas may resemble a lucency. Correlate with the AP view of the same vertebra.)

The normal spine has forward curvature in the cervical area, backward (kyphotic) curvature in the Thoracic area, and forward (lordotic) curvature in the lumbar area. If any part of the spine is straight or has a reverse curvature, seek the cause.

2. NORMAL CERVICAL SPINE

Lateral view

(i) soft tissue in front of the spine is widened in injury or infection

(a) odontoid process (b) vertebral body (c) intervertebral (disc) spaces (d) spinous processes vary in shape but are usually well defined (e) alignment-check the posterior part of the bodies (f) intervertebral foramen


PA view

(i) odontoid process (a) vertebral body

(a) vertebral body (b) intervertebral (disc) spaces (c) spinous processes vary in shape but are usually well defined (d) alignment-check the lateral part of the bodies


Always check vertebral alignment When looking at any part of the spine in the lateral view, check that there is a smooth continuous 'line' along the

posterior edges of the vertebral bodies. Check also the space between vertebrae, particularly for narrowing. (see next three images)

Forward displacement


Normal

Backward displacement

3. NORMAL THORACIC SPINE

Lateral view (a) Vertebral body (b) Pedicles (c) Intervertebral foramen (d) Intervertebral disc (e) Spinous processes (f) Transverse processes


AP view (a) Vertebral body (b) Pedicles (c) Intervertebral foramen (d) Intervertebral disc (e) Spinous processes (f) Transverse processes (g) Paravertebral soft tissue lines

4. NORMAL LUMBAR SPINE

Lateral view (a) Vertebral body (b) Disc space (c) Paravertebral joints (d) Transverse processes (e) Intervertebral foramen (f) Spinous processes (g) Sacrum


AP view (a) Vertebral body (b) Disc space (c) Paravertebral joints (d) Transverse processes (f) Spinous processes (g) Sacrum

There are normally 5 lumbar vertebrae. There may be 4, when the 5th has become "sacralized" or 6, when a sacral vertebra has become "lumbarized". Almost everyone has some developmental variation at the lumbosacral region (bifid spinous processes, asymmetry of the neural arch, absent or large transverse processes). This seldom has any clinical significance unless there is vertebral displacement.

5. AGING

Many vertebrae develop bony spurs in front and also at the back as age increases. The front spurs (see arrows in image below) are of no clinical significance. When the posterior spurs are large they can cause pressure on nerves. Many vertebrae narrow (top to bottom) and the disc spaces narrow also. Bony spurs are always present when this


happens as a result of "age" and the bones have complete outlines without any break. More than one vertebra is usually affected. This process is common and seldom causes clinical signs.

(a) normal spaces (b) narrow intervertebral disc space, sclerotic (white) edges, bony spurs either side of the disc space


These spurs can be found on any vertebra, on the sides or front of the vertebral bodies (see arrows in next three images below). They are usually asymmetrical and differ in shape. They are the result of previous injury or aging. They seldom have any clinical significance provided the vertebral bodies are not displaced or distorted.

If so many vertebrae are involved so that the spine looks like bamboo (usually in males), this may be ankylosing spondylitis. The sacro-iliac joints will be hazy or fused, with no joint space left


6. SPINAL TRAUMA

Different Types of Spinal Subluxation or Fracture-Dislocation 1. Forward displacement of C3 on C4 2. Anterior dislocation of C6 on C7 3. Fracture dislocation of C2 on C3 4. Spondylolisthesis 5. Vertical fractures 6. Wedged or compressed vertebral bodies 7. Disc degeneration

1. Forward displacement of C3 on C4

Both the anterior soft tissue line and the posterior vertebral body curve are disrupted. This is an unstable fracture. All CERVICAL and other spinal injuries need a neurological examination. These injuries can occur at any level in any part of the spine. Note: (a) - this patient has an endotracheal tube)


2. Anterior dislocation of C6 on C7

(a) There must also be a fracture of the neural arch and probably spinal cord damage.

3. Fracture dislocation of C2 on C3

(a) The neural arches have been severely fractured and the vertebral body has slipped forward.

These are both unstable fractures.

4. Spondylolisthesis

(a) At the lumbosacral junction (and also at L4/L5) there can be a defect in the neural arch and forward subluxation of the vertebral body is possible. This may be a long-standing condition that may eventually cause backache and nerve pressure symptoms. Sometimes it is a chance finding. The forward movement on L5 can be much more pronounced than in this case, and may disturb pregnancy and stop normal delivery.


There are several different types of spinal fractures. Look carefully at the shape and alignment of each vertebral body. (a) One edge may be fractured. There may be no loss of disc space or vertebral displacement. This may be a relatively minor injury.


5. Vertical fractures

Vertebral bodies can be fractured from top to bottom. This is always a severe injury. Note that the lowest vertebra is not correctly aligned with the one above; this means that there must be another injury, perhaps seen in the AP view.

6. Wedged or compressed vertebral bodies (a) In the cervical spine this is usually a serious Injury.

In the thoracic spine it is less serious clinically, but is painful. In the lumbar spine it is usually a serious injury. (b) Any vertebral mal alignment increases the severity of the injury at ALL levels. Every patient with a fractured vertebral body must be carefully checked neurologically and assessed clinically.


7. Disc degeneration Chronic disc narrowing.

No acute injury

The space between the vertebral bodies (the disc space) is narrowed when the disc is damaged. This is usually not an acute injury and may exist for a long time without symptoms. BUT if there is a history of acute trauma, look for damage to the vertebra as well. There is a fracture of the lower part of C5 anteriorly, narrowing and flattening of the disc space, and slight posterior subluxation of C5 on C6. This was an acute injury.

radiology (rad) · radiology (rad) acrrm rural clinical guidelines - radiology (rad) - version...

Documents