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…