PARS PLANITIS

Shah-Noor Hassan FCPS,FRCS(Glasgow)

Vitreo-Retina Consultant

Bangladesh Eye Hospital & Institute

History

• Cyclitis- Fuchs in 1908, Duke-Elder 1941

• Peripheral uveitis- Schepens-1950

• Peripheral cyclitis- Brockhurst et.al. - 1960

• Pars planitis- Welch et.al. - 1960

• Chronic cyclitis- Hogan & Kimura in 1961

• Vitritis- Gass et.al. - 1968

• Intermediate uveitis- IUSG- 1987

• SUN working group-2004

Nomenclature

• Standardization of Uveitis Nomenclature working group classification

• Idiopathic form of intermediate uveitis

• Includes snowballs and snowbanking

• If associated with diseases like Sarcoidosis and Lyme disease then included in intermediate uveitis

Epidemiology

• 10-25 % of all the uveitis cases

• Children and young adults

• Can occur at any age

• Both sexes are equally affected

• 80% are bilateral

• Less in Chinese and Japanese population

Etiology

• Idiopathic

• No known hereditary or environmental factors

• Some isolated cases of familial pars planitis

• Associated with various systemic diseases

• Most common- multiple sclerosis, sarcoidosis

Pathogenesis

• Immune mediated response

• But the antigenic stimulus remains speculative

• Davis and colleagues – Stage 1- immunologically mediated

– Stage 2- Non specific breakdown of intraocular regulatory mechanisms

(Not necessarily an autoimmune mechanism but even exogenous viral or bacterial antigens may be responsible)

Pathogenesis

• Escape from regulatory control of Helper T cells directed against these antigens

• Defective intraocular T cell regulation of B cells • Decreased helper to suppressor T cell ratios in aqueous

and peripheral blood • Other mechanisms

– Anterior chamber associated immune deviation– Auto retinal antibodies– Related to Demyelination – HLA-DR15 and HLA-A28 positivity– Nucleoporin like protien-nup36

Pathology

• Peripheral retina and ciliary body demonstrate condensed vitreous , fibroblasts, spindle cells, lymphocytes and blood vessels

• Prominent lymphocyte cuffing of retinal veins

• Pars plana exudates – Loose fibrovascular layer containing

scattered mononuclear inflammatory cells and a few fibrocyte like cells

– Fibroglial tissue consists of vitreous collagen, mullers cells and probable fibrous astrocytes

Clinical features

• Floaters and hazy vision

• No pain, photophobia, redness

• First episode is associated with a more severe and symptomatic iridocyclitis

• Subsequent episodes have a chronic course…….

• One eye symptomatic other eye may be asymptomatic and even show signs of active disease

Presentation

• VISION LOSS• CME, ERM

• PSC

• Vitreous Opacification

• Membranes

• Retinal Detachment

• Vitreous Hemorrhage

Presentation• Cells, flare, KPs in AC, synechiae (Spill

over anterior segment inflammation)

• Snow balls (organized vitreous inflammatory cells )

• Snow banking (exudates at pars plana)

• May be localised to inferior half

Presentation

• Peripheral vasculitis

• CME, Peripapillary retinal edema

• Vitritis, Cyclitis

• Vitreous hemorrhage

• Band shaped keratopathy

Effect on macula

• Macular edema (CME) and maculopathy (12-82 %)

• Most common cause of visual loss

• Incidence increases with duration and severity of disease

Vitreous involvement

• Vitritis

• Snowball formation

• Vitreous membranes and floaters

• Vitreous hemorrhage

Retinal involvement

• Retinal vascular changes– Tortuosity of arterioles and venules– Peripheral vascular sheathing

(Periphlebitis-16-36 %)– Neovascularizations (6.5%)– Retinal detachment (2.2-51 %)

• Causes of RD– Vitreous traction due to long standing

inflammation and subsequent hole formation

– Exudative detachment secondary to uvietis inflammation

Optic nerve involvement

• Disc edema- 3-38%

• Optic neuritis with or without multiple sclerosis was seen in 7.4 %

Complications

• Glaucoma

– Acute uveitis- 7.6 %

– Chronic – 6.5% at one year, 11.1 at 5 years

• Causes of glaucoma

– Active inflammation

– Steroid usage

– Increasing age

– Number of years since diagnosis

Cataract

• 15-50% of eyes

• Posterior or anterior subcapsular

• At times posterior cortical even posterior polar have been reported

• Incidence increases with duration and severity of disease

• If treated earlier with immunosuppressive rather than corticosteroids cataract formation is less severe

Types Of Retinal Detachment

• Exudative RD in 5-17%

• Vitreoretinal traction - in 3-22% TRRD

• Brockhurst and Schepens – 4 types of RRD

Type I:

- Low lying, chronic, associated with demarcation lines

- Small breaks near ora with exudates

- Benign course

Types Of Retinal DetachmentType II: - Large dialysis at the posterior edge of the pars plana exudate- Slowly progressive - May resolve spontaneously if VR exudation occludes the break- Seen in pts with a mild chronic inflammatory course

Type III: - Rapidly progressive

- Large breaks associated with NVVB and circumferential pars plana exudates.

- Associated with severe chronic uveitis.

Pars planitis in children

• More so as an intermediate uveitis• JIA most common cause (30%)• 1.8-29% of all uveitis• Of which 25 % are pars planitis• Mean age 8.5-10.9 years• Male preponderence• Bilateral 84-94 %• Resolves over several years• Severe visual loss is uncommon

STANDARDIZATION OF UVEITIS NOMENCLATURE

Natural course

Self limited

10 %

Smoldering

59%

Recurrent

31 %

Diagnosis

CLINICAL FEATURES

OPHTHALMIC INVESTIGATIIONS

TO RULE OUT SECONDARY CAUSES

Diagnosis: Clinical

• History• Clinical findings• Duration of symptoms, recurrences• Fever , fatigue or night sweats are typical signs -

Sarcoidosis & TB • Loss of sensitivity or paresthesias of hands, arms

or legs - Multiple sclerosis• Dermatitis, Arthritis– Lyme• Contact with cats – possibility of Bartonella

infection

Ophthalmic investigations

• V/A

• SL biomicroscopy

• IOP and

• Fundus examination with scleral depression

• Amsler grid

• OCT - Macular oedema

• Fluorescein Angiogram-

Vasculitis ,CNP areas , New vessels & CME

• B scan (Hazy media)

• UBM

• Diagnostic vitrectomy

Ophthalmic investigations

To rule out secondary causes…

• Complete hemogram• ELISA for tuberculosis and toxoplasma• CXR• Galium Scan and Chest CT

Lab Inv:- ACE levels- elevated in 60-90% of active sarcoid

patients- Lysozyme level - Elevated in granulomatous disorders

viz sarcoid, TB, and leprosy- Elevated antibody titre against Borrelia burgdorferi

• Sarcoidosis• Tuberculosis.

Differential diagnosis

• Non infectious

– Multiple sclerosis (3-27 %)

– Sarcoidosis (23-26%, IU developing sarcoidosis- 2-10%)

– Intraocular lymphoma (PCNSL- 10-20% have vitreous inflam)

• Infectious conditions

– Tuberculosis

– Syphilis (10.3%)

– Lyme disease

– Toxoplasma

– Toxocariasis

– HTLV-1, EBV, Cat scratch disease

– Endogenous endophthalmitis

– ARN, Eales, VKH, Fuch’s

MANAGEMENT

Four Step Approach (Kaplan et al)

Modified 5 step program: S.Foster et al

Topical +/ Periocular corticosteroids

Oral +/ Topical NSAID

After 3rd injection

Systemic C steroids

Inflammation persists or recurs

Peripheral retinal cryopexy /BIOL

Recur following 6th regional steroid injection

PPV/ Immunosupression

Recalcitrant inflammation

Addition of systemic steroid or immunosuppressive agents

Periocular steroid

Cryo or peripheral LASER

Vitrectomy

Corticosteroids

• Drop in VA due to vitritis, CME, progression of neovascularization at the vitreous base

• Periocular steroids-– Long acting Methyl prednisone (40 mg )– Triamcinolone acetonide (20 mg)

• Complications-– Glaucoma – Cataract – Aponeurotic ptosis– Enophthalmos– Orbital scarring

Corticosteroids

• IVTA can be given in cases of severe macular edema

• Complications

Cataract

Glaucoma

Endophthalmitis

Oral steroids

• Indicated if the disease activity is not controlled with periocular steroids

• Prednisolone 1 mg/kg/day tapered once response occurs

Immunosuppressive agents

• Antimetabolites : Methotrexate , Azathioprine

• Alkylating Agents : Cyclophosphamide , Chlorambucil

• Immunomodulators : Cyclosporine , Tacrolimus

• Complications – GI upset

– Hepatotoxicity

– Bone marrow suppression

Methotrexate

• Folate analogue which inhibits dihydrofolatereductase

• 7.5-25 mg per week oral/subcutaneous

• Can also lead to pneumonitis

• Effective and safe for chronic anterior and IU in children

Azathioprine

• Purine nucleoside analogue• Alters purine metabolism• 50-150 mg per day • GI upset and hepatotoxicity

Mycophenolate mofetil• Inhibits purine synthesis• Prevents replication of T and B lymphocytes• 1-3 mg per day• Mycophenolate is faster amongst the 3 in controlling

inflammation

Inhibitors of T-cell signaling

• Cyclosporine and Tacrolimus– Inhibit NF-AT (Nuclear Factor of Activated T-cells )

– Nephrotoxicity and hypertension are important complications

• Biological response modifiers– Daclizumab

– Infliximab

– Eternacept

– Interferon alpha

Biological response modifiers

• Daclizumab

– Humanized monoclonal ant-IL-2 receptor alpha antibody

– Suppresses auto reactive T-cells

– 1 mg/kg IV every 2 weeks for 5 doses

– Increase risk of infection

Biological response modifiers• Infliximab

– Binds to TNF and prevents its action on target tissues

• Eternacept– Dimeric, fully human, soluble TNF receptor– Binds tightly and specifically to circulating

and cell-bound TNF

• Adalimumab– Can be self administered as a subcutaneous

injection– Fully humanized so less chances of

antibody formation

• Disseminated tuberculosis is one of the fatal complications

Newer steroid implants

• Retisert

– Fluocinolone acetonide implant

– Duration of 30 months

• Ozurdex

– Dexamethasone implant

Ablative procedures

• Failed drug therapy

• At times cryotherapy is preferred before immunosuppressive Rx

• Aim

– To treat neovascularization associated with the exudates

– To destroy the peripheral vessels which bring in the inflammatory mediators

• Double row ,single freeze

• Apply to pars plana and posterior to it

• CONFLUENT BURNS• Extend 1 clock hr on either side of all areas

affected by inflammation

• EFFECTS

– Decreases vitritis and improves VA– Decrease in fluorescein in the treated area

– Induce regression of this NVVB and consequently stabilize inflammation

Cryo ablation

LASER ablation

• LASER photocoagulation works as effective as cryo

• 3-4 rows of burns are placed at the pars plana and peripheral retina

• Works on the same mechanism as cryo

Vitrectomy

• Vitrectomy for uveitis began in late 1970s• Aims

– Get rid of inflammatory mediators and immunologically competent cells

– Clear the media

• Indications – Refractory uveitis– Vision loss due to densely opacified vitreous– Scar tissue pulling on ciliary body causing hypotony– CME, ERM– Dense PCO– TRD

MANAGEMENT OF CATARACT:

• Eye - quiet for 3 months

– Preoperative – Start steroids 3 days prior

– Postoperative - slow taper.

• Technique –

– As preferred by surgeon

– Minimal trauma

– Preferably heparin coated IOL

What’s new….

• Anti VEGF agents are being evaluated in cases of uveitis with macular edema

• Lucentis and Avastin have been proved to be effective in cases of uveitic CME

Nevanac in pars planitis

• Case 1: - Short term benefit in cases of recurrent intermediate uveitis

Case 2

• Rapid resolution of vitritis in uncomplicated case of intermediate uveitis

Case 3

• Fresh case of pars planitis with CME

• Nevanac improved the CME

Summary

• Examination of pars plana • Diagnose macular edema• Rule out secondary causes• Plan appropriate treatment modility• Bold use of steroids and immunosuppressive

agents to prevent vision loss due to macular involvement

• Look out for complications• Surgical management in resistant cases and to

clear the media

Thank you…