Purpose: This study was performed to investigate the interocular symmetry of peripapillary retinal nerve fibre layer (RNFL) thickness, as measured by Cirrus high-definition spectraldomain optical coherence tomography (OCT), in healthy eyes. A wide range of subject ages and refractive errors was examined. Methods: The retinal nerve fibre layer thickness was measured in 1,234 healthy eyes from 617 subjects using OCT. Interocular differences (right eye minus left eye) in global area and quadrant nerve fibre layer thicknesses were measured. The effect of age and refractive error on interocular nerve fibre layer thickness difference was also examined. Results: Means (and standard deviations) of subjects' ages and average subject refractive errors were 36.4 ± 19.8 years (range: five to 80 years) and -2.67 ± 2.91 D (range: -14.13 to +5.75 D), respectively. Cutoff limits for normal interocular nerve fibre layer thickness differences (2.5th and 97.5th percentiles of normative data) in the global area and in the superior, nasal, inferior and temporal quadrants were 9.5, 23.0, 15.6, 20.0 and 22.6 μm, respectively. Mean interocular retinal nerve fibre layer thickness differences in global area and in superior, nasal, inferior and temporal quadrants were 0.7 (p < 0.001), -3.9 (p < 0.001), 2.6 (p < 0.001), 1.1 (p = 0.007) and 3.0 (p < 0.001) μm, respectively. Interocular nerve fibre layer thickness differences were not significantly correlated with age or refractive error (average of right and left eyes, both p > 0.05). Conclusions: Significant interocular differences in peripapillary retinal nerve fibre layer thickness exist in healthy eyes, particularly in the superior quadrant. This finding should be considered when comparing retinal nerve fibre layer thickness between right and left eyes.

Background and Objectives: To evaluate the clinical efficacy of periocular botulinum toxin A (BTA) injection in patients with intractable dry eye disease (DED). Materials and Methods: Medical records of patients with intractable DED who underwent periocular BTA injection from December 2019 to March 2020 were reviewed retrospectively. Patients were injected with 2.5 units of BTA in the medial part of the lower eyelids. The clinical data collected included age, sex, ocular surface disease index (OSDI) score, tear film break up time (TBUT), Schirmer test results, tear osmolarity (I-PEN), and tear meniscus height (TMH) measured by anterior segment optical coherence tomography. All subjective and objective data were collected before treatment and at 1 month after treatment. Results: Twenty-eight consecutive patients were eligible for chart review and analysis. Significant improvements in OSDI, tear osmolarity, and TMH were observed at 1 month after periorbital BTA injection. At the baseline and 1-month follow-up examinations, OSDI scores were 62.22 ± 21.30 and 47.98 ± 17.23, respectively (p < 0.001). TMH increased significantly after treatment (82.25 ± 40.50 at baseline vs. 138.02 ± 66.62 1-month after treatment; p < 0.001). Tear osmolarity using I-PEN showed a significant decrease after treatment (320.82 ± 24.66 at baseline vs. 302.75 ± 22.33 at 1 month after treatment; p < 0.001). No significant differences were found in TBUT or Schirmer test results before and after BTA injection. Conclusions: BTA injection into the medial part of the eyelid improves dry eye symptoms, the amount of tear retention, and tear osmolarity. Based on the objective parameters of the tear condition, this study supports the idea of BTA use as a potential treatment option for patients with intractable DED.

Purpose: To report a case of nasal-type NK/T cell lymphoma occurring in the sphenoid and ethmoid sinuses of an orbital apex syndrome patient. Case summary: A 61-year-old male patient visited our hospital for the impairment of vision in the right eye for the previous month, and for right-side blepharoptosis, pain around the eyeball, and limitation of extraocular movement in the right eye for three days earlier. In MRI (magnetic resonance image) and CT (computed tomography), shades with vague boundaries were observed in the right sphenoid and ethmoid sinuses, and open biopsy and decompression were performed for the lesions. After the surgery, the vision of the right eye increased, and improvement was observed in the right blepharoptosis, the pain around the eyeball, and in the limitation of motility of the extraocular muscle in the right eye. The patient was diagnosed with nasal type NK/T cell lymphoma in biopsy, and radiotherapy and chemotherapy were performed. J Korean Ophthalmol Soc 2010;51(2):286-291

No abstract

Purpose: To present a case of acute angle-closure glaucoma in a nanophthalmos patient. Case summary: A 28-year-old woman visited the hospital for a sudden pain in the left eye, she had a small orbital bone and narrow palpebral fissurea in both eyes. Her intraocular pressure (IOP) was 58 mmHg in the left eye. The slit lamp examination showed shallow anterior chambers in both eyes, and the gonioscopic examination showed a closed angle in the left eye. The diameters of the corneas were 11 mm , and the axial lengths were 19.7 mm in the right eye and 19.6 mm in the left eye. The depths of the anterior chambers were 1.51 mm in the right eye and 1.82 mm in the left eye. The disease was diagnosed as acute angle-closure glaucoma in the left eye of the patient with nanophthalmos, and thus the IOP of the left eye was lowered using ophthalmic drugs and medications. Laser iridotomy was performed on both eyes. Conclusions: For around a year of follow-up after laser iridotomy, complications such as the rise of intraocular pressure and choroidal effusion were not observed. This suggests that laser iridotomy can be an effective treatment for acute angle-closure glaucoma accompanying nanophthalmos.