Painless floaters and blurred vision. Minimal photophobia or complaints of external inflammation (e.g., red eye). Most often is bilateral (but can be unilateral or very asymmetric) and most frequently affects patients aged 15 to 40 years.

Critical

Vitreous cells and cellular aggregates float predominantly in the inferior vitreous (“snowballs”). Younger patients may present with vitreous hemorrhage. White exudative material over the inferior ora serrata and pars plana (“snowbank”) is suggestive of pars planitis.

NOTE Snowbanking is typically located in the inferior vitreous and can often be seen only with indirect ophthalmoscopy and scleral depression.

Other

Peripheral retinal vascular sheathing, peripheral neovascularization, mild AC inflammation, CME, posterior subcapsular cataract, band keratopathy, secondary glaucoma, ERM, peripheral retinal cysts, and tractional retinal detachments. Posterior synechiae in pars planitis are uncommon and, if present, usually occur early in the course of the disease. Choroidal neovascularization (CNV) is rare.

(See Figure 12.2.1.) 

Figure 12.2.1: Clumps of snowballs in the anterior vitreous of a young boy with pars planitis.

Diagnostic Categories

• Bartonella

• IBD-associated intermediate uveitis

• JIA-associated intermediate uveitis (in children)

• Multiple sclerosis (MS)–associated intermediate uveitis

• Pars planitis

• Sarcoidosis

• Syphilis

• TINU

• Vitreoretinal lymphoma

• Bartonella: Although, classically thought to cause neuroretinitis, Bartonella henselae may present as an isolated vitritis.

• IBD-associated intermediate uveitis: More commonly associated with Crohn disease. Causes a mild moderate–intermediate uveitis with peripheral vasculitis.

• JIA-associated intermediate uveitis: Classically causes anterior uveitis. See 12.1, Anterior Uveitis (Iritis/Iridocyclitis).

• MS-associated intermediate uveitis: May have a characteristic segmental venous sheathing. Demyelinating central nervous system (CNS) and optic nerve disease can precede or follow uveitis diagnosis. See 10.14, Optic Neuritis.

• Pars planitis: Not associated with any other systemic conditions, accounts for 20% to 40% of cases. Characteristic findings include the presence of snowballs ± snowbanks. Occurs in young men and women in early teens to young adulthood. CME is the most common cause of vision loss. Peripheral nonperfusion and subsequent neovascularization and vitreous hemorrhage may cause acute vision loss.

• Sarcoidosis: May have associated phlebitis which classically appears as “candle wax drippings.” May also have snowballs. Syphilis: See 12.10, Syphilis.

• TINU: More commonly presents with chronic smoldering bilateral anterior uveitis, but can present as a primary intermediate uveitis.

• Others: For example, Whipple disease.

• Masquerades:

  • Asteroid hyalosis: Small, white, refractile particles (calcium soaps) adherent to collagen fibers and floating in the vitreous. Typically unilateral. Usually asymptomatic and clinically insignificant. Not uncommon.

  • Amyloidosis: Retrolenticular footplate-like deposits, vitreous globules, or vitreous membranes without any signs of anterior segment inflammation. Serum protein electrophoresis and diagnostic vitrectomy can confirm the diagnosis. Rare.

  • Ocular ischemic syndrome (OIS). See 11.11, Ocular Ischemic Syndrome/Carotid Occlusive Disease.

  • Retained IOFB: Persistent inflammation after a penetrating ocular injury. May have iris heterochromia. See 3.11, Intraocular Foreign Body.

  • Schwartz–Matsuo syndrome: Pigmentary cells released from a chronic retinal detachment are suspended in the formed vitreous and may move into AC and trabecular meshwork causing elevated IOP.

  • Vitreoretinal lymphoma: Must be considered in the older patient (>55 years) presenting with vitritis. May be accompanied by transient and migrating subretinal pigment epithelium (RPE) lesions. Often lacks other stigmata of uveitis such as posterior synechiae, CME (∼10%), and doesn’t show leakage on IVFA.

  • Other neoplasms: For example, retinoblastoma (in children), metastatic disease.

   

1. Obtain a thorough history and review of systems. In particular ask about arthralgias, rash, a history of sexually transmitted diseases, high-risk sexual activity, difficulty breathing, exposure to cats, neurologic symptoms (deficits or headaches), foamy or frothy urine, kidney dysfunction, bloody or loose bowel movements.

2. Complete ocular examination, including an IOP check, gonioscopy, and a dilated fundus examination.

3. Consider OCT to detect CME.

4. Consider an IVFA to detect subtle vasculitis, peripheral nonperfusion, peripheral neovascularization, or to monitor response to therapy.

5. Focused serologic testing based on history and examination

   • Treponemal test (syphilis EIA, FTA-ABS, TP-PA), followed by confirmatory nontreponemal test (RPR, VDRL). See 12.10, Syphilis.

   • Interferon gamma releasing assay (IGRA, QuantiFERON Gold) and/or PPD. Consider chest imaging (CXR or CT chest) to assess for signs of active or prior pulmonary disease.

     • In those at risk for TB (e.g., immigrants from high-risk areas such as India, HIV-positive patients), homeless patients, or prisoners.

     • If considering immunosuppressive therapy (especially biologics).

   • ACE, lysozyme, and chest imaging (CXR or CT chest).

   • Urinary beta-2 microglobulin, urinalysis, and renal function testing are useful in making a diagnosis of TINU.

   • Bartonella serum antibody or PCR testing.

6. Consider magnetic resonance imaging (MRI) of the brain and orbits with and without gadolinium contrast to evaluate for demyelinating lesions in the setting of suspect MS-associated intermediate uveitis (characteristic findings or positive neurologic deficits on review of systems) or to evaluate for comorbid CNS lesions if vitreoretinal lymphoma is of concern.

7. Consider referral to a vitreoretinal surgeon or ocular oncologist to perform a diagnostic vitrectomy ± retinal biopsy if concerned for possible vitreoretinal lymphoma. Specimens should be evaluated as soon as possible by an ocular pathologist or a neuropathologist with experience in working with vitreous specimens. Consider MYD88 mutation testing and IL-6/IL-10 ratio testing.

Mild vitreous cells in the absence of significant symptoms, CME, or vision loss may be observed in cases of noninfectious intermediate uveitis. Treat all vision-threatening complications (e.g., CME, progressive snowbanks, peripheral nonperfusion) in symptomatic patients with active disease.

1. Topical prednisolone acetate 1% or difluprednate 0.05% q.i.d.–q2h.

2. Treat infectious etiologies with appropriate antimicrobials prior to using local long-acting ocular steroids or systemic steroids.

   • For syphilis treatment, see 12.10, Syphilis.

3. Consider a trial of oral steroids if bilateral and incomplete response to topical steroids.

   NOTE In bilateral cases, systemic steroid therapy may be preferred to periocular injections. However, in children and adolescents, growth suppression (in addition to the usual complications of long-term systemic steroids) is a major concern.

4. Consider local steroid injection if unilateral or there is CME that is resistant to topical steroids.

5. If the disease becomes persistent, consider long-acting local steroids (0.19 mg or 0.59 mg fluocinolone acetonide implants) versus systemic steroid-sparing immunosuppression (e.g., antimetabolites, calcineurin inhibitors, and anti-TNF agents).

   NOTE TNF-alpha inhibitors (e.g., adalimumab, infliximab) should be avoided in patients who are suspected of having MS-associated intermediate uveitis as they can precipitate or worsen demyelinating CNS disease.

6. IVFA-guided panretinal photocoagulation should be considered in those with severe peripheral nonperfusion, active peripheral neovascularization, or complication from active peripheral neovascularization (e.g., vitreous hemorrhage). 

NOTE Some physicians delay steroid injections for several weeks to observe whether the IOP increases on topical steroids (steroid response). If a marked steroid response is found, depot injections are relatively contraindicated. Intravitreal steroids are more effective for uveitic macular edema than periocular steroids. Consider adding topical NSAIDs in patients with CME, especially those who have steroid response ocular hypertension. Cataracts are a frequent complication of intermediate uveitis. If cataract extraction is performed, the patient should ideally be free of inflammation for 3 months preceding the operation. Consider starting the patient on oral prednisone 60 mg daily 2 to 5 days prior to surgery and tapering the prednisone over the next 1 to 4 weeks. Aggressive perioperative use of topical NSAIDs (e.g., ketorolac 0.5% q.i.d.) and topical steroids (e.g., prednisolone acetate 1% q2h or difluprednate 0.05% six times a day) starting 5 to 7 days preoperatively and continued for at least 4 to 6 weeks postoperatively may reduce the risk of pseudophakic CME and recurrent uveitis.

1. In the acute phase, patients are reevaluated every 1 to 4 weeks, depending on the severity of the condition.

2. In the chronic, well-controlled phase, reexamination is performed every 3 to 6 months.