Effect of Adjunctive Pars Plana Vitrectomy on Focal Posterior Segment Inflammation: A Case-Control Study in...

Pars plana vitrectomy (PPV) is commonly performed for managing complications of uveitis but the anti-inflammatory potential of PPV has not been extensively investigated beyond aqueous/vitreous inflammation. We studied the effect of PPV on resolution of focal posterior segment lesions in tuberculosis-associated uveitis (TBU).

Case control study.

Patients with bilateral TBU and active retinal/choroidal lesions in both eyes, and who received PPV in one eye were included. Fellow eyes of same patients, matched for patient characteristics and systemic therapy, were designated as controls.

Study eyes received 3-port 23-guage PPV, involving removal of nearly the entire vitreous. Part of vitreous sample was used for quantitative polymerase chain reaction (qPCR) for Mycobacterium tuberculosis. Post-operatively, anti-TB and/or systemic corticosteroid therapy was initiated depending on level of clinical suspicion of tubercular etiology, degree of intraocular inflammation and qPCR results. Focal lesions were documented in preoperative and postoperative fundus diagrams. Clinical photographs were taken whenever adequate media clarity was present.

Primary outcome measures were rate of clinical resolution of focal posterior segment lesions and improvement in best-corrected visual acuity (BCVA), at 1 month post-surgery.

Thirty-six patients with bilateral posterior segment lesions consistent with TBU were included. Possible and probable TBU (depending on radiographic evidence of TB) were diagnosed in 28 (77.7%) and 4 (11.1%) patients respectively, whereas remaining 4 patients were diagnosed only on basis of qPCR results. Focal posterior segment lesions included retinal vasculitis (n = 27), multifocal-serpigenoid choroiditis (n = 5), multifocal choroiditis (n = 3) and focal choroiditis (n = 1). At one month postvitrectomy, 28 eyes (73.7%) showed complete resolution of focal posterior segment lesions compared to 7 non-vitrectomised eyes (19.4%), while improvement in BCVA was significantly more in study eyes (0.38 logarithm of the minimum angle of resolution [logMAR], P = 0.04), compared to controls (0.12 logMAR, P = 0.17). Time to resolution following vitrectomy was unaffected by duration of disease, pre-operative systemic steroids or grade of vitritis. At 3 months, complete resolution was noted in 29 of 30 study eyes (96.7%) and 25 of 30 control eyes (83.3%).

PPV facilitates faster resolution of focal posterior segment inflammation and BCVA improvement in TBU.