To observe the efficacy and safety of intravitreal methotrexate (MTX) in the treatment of primary intraocular lymphoma (PIOL) according to the clinical behavior of the lymphoma.

The clinical data of 20 patients (30 eyes) with PIOL who visited the Department of Ophthalmology, Beijing Chaoyang Hospital affiliated to Capital Medical University from April 2013 to December 2019 were collected. Among them, there were 6 males (6 eyes) and 14 females (24 eyes) with an average age of (55.9±12.4) years (ranged from 34 to 81 years). All patients were diagnosed with diffuse large B cell lymphoma. The treatment plan is individualized treatment according to the clinical manifestations of lymphoma, and all eyes received a single intravitreal injection of MTX (400 μg∶0.1ml). When the vitreous opacity of patients increased, enlarged fundus lesions or IL-10/IL-6 increased, then re-injection was performed. They were followed up for 12 to 30 months after intraocular chemotherapy. Best corrected visual acuity (BCVA), intraocular pressure, slit lamp microscopy, color fundus photography, optical coherence tomography, fundus fluorescein angiography and the concentration of IL-6 and IL-10 were performed. The measurement data such as BCVA (represented by LogMAR), intraocular pressure (IOP) and other measurement data were tested for normality. IOP conforming to normal distribution were expressed as ±s, and compared by paired t test before and after treatment; BCVA not conforming to normal distribution were expressed as median and quartile, and compared by Wilcoxon paired rank-sum test. Slit lamp microscopy, color fundus photography, optical coherence tomography, fundus fluorescein angiography and IL-10/IL-6 are described in text.

The median LogMAR visual acuity before and after treatment was 0.75 (0.47, 1.43) and 0.4 (0.2, 0.57), and the difference was statistically significant (Z=3.43, P < 0.05). The IOP of patients before and after treatment was (16.56±4.31) mmHg (1 mmHg=0.133 kPa) and (16.13±3.87) mmHg, respectively, and the difference was not statistically significant (t=0.40, P> 0.05). In all patients, there were 12 cases (19 eyes) with improved vitreous opacity after intravitreal injection of MTX, accounting for 63% (19/30), 15 cases (20 eyes) with reduced or disappeared the yellow and white creamy lesions in the subretinal, accounting for 66% (20/30), and 13 cases (18 eyes) with reduced or disappeared the hyperreflexive lesions in the subretinal pigment epithelium, accounting for 60% (18/30). The number of injections ranged from 1 to 8, with an average of (3±2.37).

Intravitreal injection of MTX according to the clinical behavior of the lymphoma is safe and effective in the treatment of PIOL, which could achieve the clinical remission.