macquarie neurosrgery evidence based surgery

MACQUARIE NEUROSURGERYEVIDENCE BASED SURGERY

Is cine phase-contrast MRI able to predict resolution of headache in patients with Chiari malformation type 1 undergoing posterior fossa decompression

Bryden Dawes13/09/2016

Clinical case

46 year old femaleFamily history – CM-1 daughter

Headaches since childhood5 year history occipital headacheValsalva headache

Lumbar puncture – opening pressure 20cmH20

No Neurological deficit

MRI – 8mm caudal descentCrowding of foramen magnumNo syrinx

Clinical case

Phase contrast - Reduced flow dorsal to cerebellum- Normal ventral flow

Posterior fossa decompression

3 month follow up – no further headaches

Cine Phase - contrast MRI

• Cine MR technique that demonstrates biphasic CSF flow

- Cranial flow black- Caudal flow white

• CM-1 - CSF flow at level of foramen magnum• Qualitative and quantitative assessments• Qualitative assessment - interobserver and

intraobserver variability• Dichotomised or 3 point scale

- Absent flow - Reduced flow

- Normal flow • Quantitative flow velocities can be measured –

point measurement

PICO question

P – Type 1 Chiari malformation with headache undergoing surgeryI – CSF flow abnormality on FC MRIC – Normal CSF flow on FC MRIO – Post operative headache

‘In a patient with a CM-1 and headache undergoing surgery does a CSF flow abnormality on FC MRI compared with normal CSF flow lead to better post operative headache’.

Search Strategy

• Ovid medline• EMBASE• Scopus• Reference / citation review of key papers

Inclusion criteria• CM-1 with and without syrinx• Paediatric and adult• Minimum 10 patients – surgical cases• Post surgical data• Clinical correlation

Ovid Medline

Ovid Medline

Ovid Medline

EMBASE

Scopus

PRIS

MA

Summary of papers

Autor Title Year Journal Institution

McGirt et al (1)Correlation of CSF fluid flow

dynamics and headache in Chiari 1 malformation

2005 Neurosurgery Duke UMC

McGirt et al (2)Relationship of cine phase-

contrast MRI to outcome after decompression for CM1

2006 Neurosurgery Duke UMC

Koc et alChiari 1 malformation with

syringmyelia: correlation of phase contrast cine MR imaging and

outcome2007 Turkish

NeurosurgeryKocalli Medical Centre, Turkey

McGirt et al (3)Correlation of hindbrain CSF flow

and outcome after surgical decompression for Chiari 1

malformation2008 Child's Nervous

system John Hopkins

Ovid Medline

McGirt Papers

Matthew J McGirt

• Associate Professor - University North Carolina

• MD at Duke• Residency at John Hopkins• Complex Spine

Summary of papers

Autor Design Number of surgical patient Mean age Syrinx Headache

McGirt et al (1) Retrospective 17 (30 included) 14 (3 - 26) 0 17/17

McGirt et al (2) Retrospective 130 16 (3-29) 46/130 104/130

Koc et al Not specified 18 34.5 (19 -56) 18/18 14/18

McGirt et al (3) Retrospective 44 8 (2-14)* 8/44 35/44

* Paediatric hospital

Summary of papers

Autor MR analysis Operation Follow - up Outcome Assessment

McGirt et al (1)Qualitative –

dichotomised Craniectomy, C1 laminectomy &

duroplasty 12 months No scale

McGirt et al (2) Qualitative – dichotomised

Craniectomy, C1 laminectomy &

duroplasty 19 months (Mean) No scale

Koc et al Qualitative and fCSF velocity

Craniectomy, C1 laminectomy &

duroplasty (lyophilised)

26 months Functional scoring system

McGirt et al (3)

Qualatative (presence of biphasic flow

ventral and dorsal to brainstem)

Craniectomy, C1 laminectomy &

duroplasty (Synthetic)

27 months (Mean) No scale

Results

• N = 30 (17 surgical cases)• 12 patients with headache and

PC abnormality• 100% improvement

Results

• N = 130 • 81 % abnormal CSF flow• 33% symptom recurrence at

Results

• N = 18 • 100 % abnormal CSF flow• 11% symptom recurrence• Poor analysis and difficult to interpret

Results

• N = 44• 68 % abnormal CSF flow• 30% symptom recurrence at

follow up• Abnormal dorsal CSF not

significant• Abnormal ventral flow RR 2.6

Conclusions

• Evidence poor quality• Small number of studies• Author bias• MR assessment - qualitative

assessment• Clinical outcome – records review• Phase contrast abnormality appears to

be an independent predictor of good outcome following surgery