Two Cases of Conjunctival Mucosa-associated Lymphoid Tissue (MALT) Lymphomas Treated by Cryotherapy

PURPOSE: To report two cases of conjunctival mucosa-associated lymphoid tissue (MALT) lymphomas treated with cryotherapy. CASE SUMMARY: Two patients with MALT lymphoma of the conjunctiva were treated by carbon dioxide cryotherapy under topical anesthesia using 0.5% proparacaine hydrochloride (Alcaine(R), Alcon). Cryotherapy was repeated in recurrent lesions up to three times. One patient was free of the tumor for 18 months of follow-up after the third cryotherapy was performed. The second patient had complete disease arrest for 9 months after the third cryotherapy. Neither patient experienced complications during the follow-up period. CONCLUSIONS: Cryotherapy is a comparatively easy treatment tool with fewer complications for patients, making it preferable from a patient's perspective as well. Cryotherapy may be a useful treatment modality in patients with MALT lymphomas localized to the conjunctiva.

Clinical Study of A-V Pattern Strabismus in Korea

PURPOSE: To assess the prevalence of A-V pattern strabismus and evaluate the clinical characteristics, surgical methods and outcomes. METHODS: Among 825 patients who underwent horizontal strabismus surgery, the records of patients with A-V pattern strabismus were reviewed retrospectively. The prevalence and clinical characteristics of patients with A-V pattern strabismus were assessed and the surgical methods and outcomes of A-V pattern strabismus were evaluated. RESULTS: Among 825 patients with horizontal strabismus surgery, 113 (13.7%) patients had A-V pattern. V exotropia was the most common (65.5%) and A esotropia was the least common (7.1%) pattern. A +1.9 inferior oblique overaction in 92.8% of the V-pattern patients and a +1.5 superior oblique overaction in 70.0% of the A pattern patients was found. Among the 113 patients, 64.6% patients underwent oblique muscle surgery and 35.4% patients underwent vertical transposition of horizontal muscle. Vertical incomitance was significantly reduced after surgery in all types of A-V pattern strabismus (p<0.05) with a surgical success rate of 96.5%. CONCLUSIONS: A 13.7% prevalence of A-V pattern in horizontal strabismus patients was found, with V exotropia being the most common. The vertical incomitance was successfully corrected after surgery.

Clinical Study of A-V Pattern Strabismus in Korea

PURPOSE: To assess the prevalence of A-V pattern strabismus and evaluate the clinical characteristics, surgical methods and outcomes. METHODS: Among 825 patients who underwent horizontal strabismus surgery, the records of patients with A-V pattern strabismus were reviewed retrospectively. The prevalence and clinical characteristics of patients with A-V pattern strabismus were assessed and the surgical methods and outcomes of A-V pattern strabismus were evaluated. RESULTS: Among 825 patients with horizontal strabismus surgery, 113 (13.7%) patients had A-V pattern. V exotropia was the most common (65.5%) and A esotropia was the least common (7.1%) pattern. A +1.9 inferior oblique overaction in 92.8% of the V-pattern patients and a +1.5 superior oblique overaction in 70.0% of the A pattern patients was found. Among the 113 patients, 64.6% patients underwent oblique muscle surgery and 35.4% patients underwent vertical transposition of horizontal muscle. Vertical incomitance was significantly reduced after surgery in all types of A-V pattern strabismus (p<0.05) with a surgical success rate of 96.5%. CONCLUSIONS: A 13.7% prevalence of A-V pattern in horizontal strabismus patients was found, with V exotropia being the most common. The vertical incomitance was successfully corrected after surgery.

Effect of Nitric Oxide on the Trabecular Meshwork Cell-mediated Contraction of Collagen Gels

PURPOSE: To investigate the effect of nitric oxide (NO) on the contraction of cultured human trabecular meshwork cells (HTMCs). METHODS: After embedding them into collagen gels, primarily cultured HTMCs were exposed to NO donors, such as sodium nitroprusside (SNP) or S-Nitroso-N-acetylpenicillamine (SNAP), for 1 week at various concentrations, and the contraction of the collagen gels was measured. Cellular survival and NO production were measured with MTT assay and Griess assay, respectively. RESULTS: Though SNP and SNAP did not significantly affect cellular survival, they markedly enhanced NO production. Both sodium nitroprusside and SNAP inhibited the contraction of collagen gels by about 10% in dose and time-dependent manners (p<0.05). CONCLUSIONS: NO donors inhibited the contraction of collagen gels in vitro. Thus, NO donors may relax trabecular meshwork and enhance trabecular outflow.

Effects of Triamcinolone Acetonide in Cultured Trabecular Meshwork Cells

PURPOSE: To investigate the effect of triamcinolone acetonide (TA) on the survival, nitric oxide (NO) production, and migration of cultured human trabecular meshwork (TM) cells. METHODS: After exposure to TA, indomethacin, and dexamethasone for 2 days, the survival and nitrite production of the primarily cultured human TM cells were assessed with MTT and Griess assays respectively. The effect of co-exposure to the NO donor, sodium nitroprusside, was also assessed. A migration assay was done to evaluate the effect of TA on the activity of TM cells. RESULTS: Cellular survival increased after exposure to TA at low concentration but decreased at high concentration. TA decreased the production of NO significantly (p<0.05). Exposure to indomethacin and dexamethasone revealed similar results. TA reversibly inhibited the migration of TM cells. CONCLUSIONS: TA decreases the production of NO and inhibits the migration of TM cells. TA at high concentration decreases cellular survival accompanied with decreased NO production. These effects of TA on TM cells may result in the elevation of intraocular pressure.