INTERMEDIATE UVEITIS

PRESENTER- DR BARUN GARGMODERATOR- DR HIMANTO HAZARIKA

RIO, GUWAHATI

ANATOMY

• Pars plana is a flat extension from posterior aspect of ciliary processes to ora serrata

• 3.5 to 4 mm in length• Around 3 mm from limbus- ciliary processes

INTRODUCTION

Inflammation of uveal tract – UVEITIS

ANATOMICAL CLASSIFIACTIONA)ANTERIOR- iritis, anterior cyclitis, iridocyclitisB)INTERMEDIATEC)POSTERIOR- choroiditis, chorioretinitis,

retinochoroiditis, neuroretinitisD)PANUVEITIS

International Uveitis Study Group (IUSG)

Anatomic Classification of Uveitis*

Anterior uveitisPrimary site of inflammation: anterior chamber

Intermediate uveitisPrimary site of inflammation: vitreous

Posterior uveitisPrimary site of inflammation: retina or choroid

PanuveitisPrimary site of inflammation: anterior chamber, vitreous, retina or choroid

INTERMEDIATE UVEITIS• Intermediate uveitis (IU) is described as inflammation in

the anterior vitreous, pars plana and the peripheral retina• The diagnostic term pars planitis should be used only for

that subset of IU where there is snow bank or snowball formation occurring in the absence of an associated infection or systemic disease

DEMOGRAPHY OF INTERMEDIATE UVEITIS

• Incidence in population – 1 in 15000• % of IU in cases of uveitis- 8 to 22%• Incidence in indian referral eye hospital-

19.8%• Male: female- 54:46• Average age in various studies- 23 to 28 years• Bilateral- 70 to 90% at presentation

• The IUSG (International Uveitis Study Group) suggested the term IU to denote an idiopathic inflammatory syndrome, mainly involving the anterior vitreous, peripheral retina and the ciliary body with minimal or no anterior segment or chorioretinal sign

• IU is not hereditary though it has been observed in families.

• patients who are HLA-DR15-positive and have IU may have systemic findings of another HLA-DR15-related disorder- multiple sclerosis, optic neuritis, and narcolepsy

ETIOPATHOGENESIS

• Exact theory yet to be known• may be initiated by an unknown antigen, leading to a

clinical picture of vasculitis and vitreous cells.• antigen may be infectious(Lyme's, syphilis and cat-

scratch fever) , autoimmune-(multiple sclerosis and sarcoidosis)

• Type II collagen in the vitreous may be an autoantigen in some patients

contd...

• Intermediate uveitis seems to be a T-cell-mediated disease

• Lymphocytic infiltration of the retinal venules leads to the clinical picture of vasculitis.

• T-cells are the predominant cell type in the vitreous up to 95% of all cells, of which CD4+ cells are 35-90%.

• Macrophages -second most important cells• In active inflammation epitheloid cells and

multinucleated giant cells are seen• HLA associations include HLA-DR, B8, and B51, the

most significant being HLA-DR which occurs in 67-72% of patients

HISTO-PATHOLOGY

• Histological studies of the peripheral retina and ciliary body demonstrate – condensed vitreous, fibroblasts, spindle cells, lymphocytes and blood vessels and prominent lymphocyte cuffing of retinal veins.

• Pars plana exudates appear to consist of loose fibrovascular layer containing scattered mononuclear inflammatory cells and a few fibrocyte-like cells adjacent to the hyperplastic nonpigmented epithelium of the pars plana.

CLINICAL FEATURESOne of the most under diagnosed uveitic disease- lack of routine examination of pars

plana, lack of awareness SYMPTOMS-(initially)• floaters• Mild blurring of vision• Mild photophobia• Uncommon- pain, redness

SIGNS-• Conjunctiva- mild congestion• Anterior chamber- no or minimal findings• Cells and flare, KPs, posterior synechiae ( usually inferiorly) • Vitritis is a characteristic feature of IU, and it is

typically described as vitreous haze ranging from trace to 4+

FUNDOSCOPY-• Characteristic mobile, globular, yellow-white

"snowballs" ("ants' eggs") seen in the inferior peripheral vitreous.

• They lie close to the retina, but are not in contact with it.

• Inflammatory exudates accumulate over pars plana to form SNOWBANK

• Periphlebitis of peripheral veins in vicinity of exudates

CONTD....• Later the vitreous shows degenerative changes

with fibre-like cylindrical condensations of coarse vitreous strands.

• Posterior vitreous detachment (PVD) is common• Retinal changes in IU include tortuosity in

arterioles and venules, sheathing of peripheral veins, neovascularizations and retinal detachments

• Cystoid macular edema

The hallmark of pars planitis are• the white or yellowish-white pars plana

exudates ("posterior hypopyon") and • collagen band (snowbank) over the pars plana. • These exudates are preretinal, peripheral,

typically inferior but may also be superior or divided into multiple foci or extend 360 degrees over the entire pars plana

DIFFERNTIAL DIAGNOSIS

Contd...MOST COMMON-• Idiopathic • Syphilis • Lyme disease• Multiple sclerosis• Sarcoidosis• Bartonella

LESS COMMON-• Lymphoma• HTLV• Toxocara• behcets

• TABLE 1295

Multiple sclerosis: About 3-27% of patients develop pars planitis and 7.8-14.8% of patients with IU/pars planitis develop MS.

• characterized by pars plana snowbanks, retinal periphlebitis (in 5-20%) and panuveitis are the commonest manifestations of MS and up to 95% are bilateral

Intraocular lymphoma:10-20% the disease commences as vitreous or retinal infiltrates mimicking uveitis and 95% are non-Hodgkins B-cell lymphomas

Sarcoidosis: About 23-26% of patients with sarcoidosis develop IU

• typical ocular findings-CME, optic disc swelling, periphlebitis, and retrobulbar optic neuritis were seen in patients with IU, both with or without sarcoidosis

• It is commonly bilateral, and presents as IU and granulomatous anterior uveitis

Syphilis: uveitis is the commonest presentation of syphilis. • Anterior uveitis( granulomatous and

nongranulomatous), posterior uveitis, panuveitis, vitritis, vasculitis, retinitis, placoid choroiretinitis and optic nerve involvement are also seen in eyes with syphilitic uveitis.

• IU has been described to occur in Lyme's disease caused by another spirocheate- Borrelia burgdorferi, both in adults and in children

DIAGNOSIS

• Diagnosis is based on clinical findings• patient's history should focus-duration of

symptoms, the number of recurrences, and findings that might be associated with systemic disorders

Ancillary test-FFA- detection of CME - capillary and disc hyperflourescence,

staining of vessel wall, fern pattern radial hyperflourescence

• USG- exudates over pars plana• ERG- abnormal b wave implicit time• UBM- exudates and vitritis

LAB INVESTIGATIONS

• Baseline invs- CBC, ESR, RFT,LFT, • PPD test - exclude tuberculosis/sarcoidosis• Chest X-ray-- findings indicative of sarcoidosis or

tuberculosis.• Sarcoidosis – CT scan lungs, ACE enzymes• Serologic testing for- cat-scratch disease, syphilis

(VDRL, FTA-ABS)and Lyme's• HLA DR2 typing• Vitreous tap

COMPLICATIONS

1)CME-Upto 50% patientsMost common cause of visual lossPrevalance increases with severity of

inflammation Epiretinal membrane

CATARACTS-• Either due to inflammation or steroids• Most often type – PSC• 15-50% of eyes

• GLAUCOMA

• Optic disc edema- due to intraocular inflammation

20% patients• optic neuritis – may or may not be associated

with multiple sclerosis

• NVD/NVE

• Venous sheathing- most often benign

• VASCULITIS- associated with ischaemia Sheathing +/-

• Retinal detachmentA) Serous RDB) Rhegmatogenous RD- associated with dialysis at

snow bank

TREATMENTFour step approach by KaplanStep 1-• Posterior sub tenon injection of steroids- methyl prednisolone 40mg or

triamcinolone 40 mg (0.75 to 1 ml)• Preferably in upper temporal quadrant• 2 to 3 injections at interval of 3-4 weeks- resolution• Topical 1% prednisolone acetate• Systemic steroids 1mg/kg can be added (mantoux test to be done)• Improvement in vision 67% cases• Appropriate antibiotics for infections causes

Compliactions- rise in iop, ptosis, globe perforation, necrotising scleritis

Step 2-• Not responded to peri ocular/ systemic steroids• Cryopexy can be done• Mechanism- destruction of hyperemic vascular

component of diseases by eliminating neovasclar and ischaemic tissue

• Double freeze and thaw technique• Impovement in vision- 32 to 67 percent• Complications- RD, PVR• Doesnt prevent recurrence• Indirect laser also used

Step 3-• Not responding to cryopexy also• Pars plana vitrectomy is done• Helps in early resolution of CME

Step 4-• If step 1 fails- immunosuppresive agents can be used• Cyclophosphamide, azathioprine, chlorambucil• Azathioprine- 50 mg thrice daily for four

months(tapered)• Platelet counts, WBC regularly monitored

Current guidelines in many institutes

• Some advocate use of a combination of betamethasone and depot methylprednisolone(sub tenon) in an effort to achieve early onset and prolonged duration of action.

• Intravitreal triamcinolone acetonide injections have been used to treat CME

• use of somatostatin analogues (Octreotide) IM and intravitreal bevacizumab (Avastin) in patients with refractory uveitic CME.

• the surgical implantation of a fluocinolone acetonide (Retisert) or dexamethasone (Ozurdex) implant can be considered

STEROID REFRACTORY UVEITIS• Cyclosporine, tacrolimus, azathioprine, and methotrexate are the most

commonly used agents with documented efficacy in many uveitic conditions• Chlorambucil can be considered for intractable casesNEWER DRUGS USED-• infliximab, (anti-TNF) monoclonal antibody, has been shown to be effective

in improving macular thickness and visual acuity in patients with uveitic refractory CME due to intermediate uveitis or other noninfectious uveitis.

• Daclizumab, an interleukin-2 receptor blocking antibody, has been shown to be effective in noninfectious uveitis in a multicenter nonrandomized interventional case series

• interferon-beta (INF-beta), which has an established value in the treatment of MS, appears to have a positive effect in terms of visual acuity, CME

• MANAGEMENT OF GLAUCOMA• Rx OF CATARACT• Anti VEGF for neovascularisation• Supportive rx