3. • 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
6. International Uveitis Study Group (IUSG)
Anatomic Classification of Uveitis*
Anterior uveitis
Primary site of inflammation: anterior chamber
Intermediate uveitis
Primary site of inflammation: vitreous
Posterior uveitis
Primary site of inflammation: retina or choroid
Panuveitis
Primary site of inflammation: anterior chamber, vitreous, retina or
choroid
7. 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
8. 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
9. • 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
10. • 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
11. 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...
12. • 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
13. 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.
14. CLINICAL FEATURES
One 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
15. 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+
16.
17. 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
18.
19. 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
20.
21. 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
26. 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
27. 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
28. 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
29. 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
30. Ancillary test-
FFA- detection of CME
- capillary and disc hyperflourescence,
staining of vessel wall, fern pattern radial
hyperflourescence
31. • USG- exudates over pars plana
• ERG- abnormal b wave implicit time
• UBM- exudates and vitritis
34. CATARACTS-
• Either due to inflammation or steroids
• Most often type – PSC
• 15-50% of eyes
• GLAUCOMA
35. • Optic disc edema- due to intraocular
inflammation
20% patients
• optic neuritis – may or may not be associated
with multiple sclerosis
• NVD/NVE
36. • Venous sheathing- most often benign
• VASCULITIS- associated with ischaemia
Sheathing +/-
• Retinal detachment
A) Serous RD
B) Rhegmatogenous RD- associated with dialysis at
snow bank
37. TREATMENT
Four step approach by Kaplan
Step 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
38.
39. 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
40. 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
42. • 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
43. 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 cases
NEWER 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
44. • MANAGEMENT OF GLAUCOMA
• Rx OF CATARACT
• Anti VEGF for neovascularisation
• Supportive rx
