Comparison of Delayed-Onset Glaucoma and Early-Onset Glaucoma after Infantile Cataract Surgery

PURPOSE: To investigate the causes and characteristics of glaucoma in children following cataract surgery. METHODS: Twenty-four patients (37 eyes) with uncomplicated congenital cataracts who developed glaucoma after cataract surgery were studied retrospectively. Variables included cataract morphology, surgical techniques, post-operative complications, time to the onset of glaucoma, gonioscopic findings, presence of microcornea and the histopathologic characteristics of the filtration angle (in one case). RESULTS: There was a bimodal onset of glaucoma after cataract surgery. Early-onset glaucoma occurred at a mean age of 6 months in 15 eyes and delayed-onset glaucoma at a mean age of 12 years in 22 eyes. Early-onset glaucoma was significantly (p=0.018) more likely to be due to angle closure than delayed-onset glaucoma. With delayed-onset glaucoma, the filtration angle was open in 86% of eyes and significantly (p=0.006) more eyes in the delayed-onset group had microcornea. Medical treatment was sufficient to control intraocular pressure in the delayed-onset group while the early-onset group required surgical treatment (P<0.001). CONCLUSIONS: The onset of glaucoma after cataract surgery during infancy follows a bimodal pattern that is correlated with the configuration of the filtration angle. The early-onset glaucoma group had high incidence of angle closure requiring surgical treatment, while in the delayed-onset group non-surgical treatment was sufficient to control intraocular pressure. Prophylactic iridectomy in eyes at risk for pupillary block is recommended. Eyes with delayed-onset glaucoma have open filtration angles yet also have findings of incomplete development of filtration structures. Microcornea is a risk factor for delayed-onset glaucoma.

Graded Partial Tenotomy of Vertical Rectus Muscles for Treatment of Hypertropia

PURPOSE: To evaluate the effectiveness of graded (adjustable intraoperatively) partial vertical rectus muscle tenotomy at the insertion in correcting small degrees of hypertropia. METHODS: All patients with best corrected visual acuity of better than 6/30 in both eyes who had undergone only partial tenotomy of vertical rectus muscle(s) over a 30-month period were included. Improvement was evaluated 6 weeks postoperatively as the change in alignment in prism diopters (PD) in primary gaze and in the field of action of the affected rectus muscle(s). Binocular function was evaluated by Titmus stereoacuity and the Worth 4-light tests. RESULTS: All 24 patients who met the inclusion criteria had diplopia preoperatively, and this had resolved in 17 (71%) postoperatively (P<0.005). Prisms were used by 6 preoperatively vs. 2 postoperatively (P<0.05). The average vertical deviation in primary gaze decreased from 8 PD to 2 PD (P<0.005). In the field of action of the treated rectus muscle, hypertropia decreased from an average of 8 PD to 3 PD (P<0.005). For the available pre- and post-operative assessments, stereoacuity improved after 10 of the 18 (56%) procedures and Worth 4-light testing showed improvement or maintenance of fusion after 13 of 19 procedures (68%). CONCLUSIONS: Graded vertical rectus partial tenotomy can effectively reduce small degrees of hypertropia and associated diplopia, improve binocular function, and reduce or eliminate the need for prism correction.