Maura Smith

Effects of topical mitomycin C on primary trabeculectomies and combined procedures

The charts were reviewed of all patients who underwent primary trabeculectomies (group 1) or combined procedures (phacoemulsification + intraocular lens implantation + trabeculectomy--group 2) and received intraoperative mitomycin C (0.4 mg/ml) between 1991 and 1992 at Wills Eye Hospital. A total of 54 eyes of 54 patients were included: 39 in group 1 and 15 in group 2. Intraocular pressure was controlled successfully in 97.4% of eyes in group 1 (mean follow up 6.7 months), and in 93.3% in group 2 (mean follow up 6.8 months). Main complications included choroidal detachment (n = 15), shallow anterior chamber (n = 9), cataract formation (n = 8), and hypotony maculopathy (n = 3). The use of mitomycin C in primary trabeculectomies and combined procedures is associated with high success rates. However, it may be associated with unacceptable risks of vision threatening complications related to excessive filtration.

Glaucoma in the Immediate Postoperative Period After Penetrating Keratoplasty

In a prospective study 155 consecutive patients undergoing penetrating keratoplasty were examined for postoperative increase in intraocular pressure to determine the frequency and duration of intraocular pressure spikes, risk factors, and response to treatment. Patients were maintained on preoperative glaucoma medications except miotics. Additional medications to lower intraocular pressure perioperatively were not given. Intraocular pressure was measured two to five hours, one day, and one week postoperatively. An intraocular pressure of 30 mm Hg or greater was considered an increase in pressure and was treated according to a standardized protocol. The results were analyzed by procedure as well as by variables commonly perceived to be associated with intraocular pressure increase (history of glaucoma, use of hyaluronate, lysis of the synechiae, or vitrectomy at the time of the operation). Overall, intraocular pressure increases in the early postoperative period occurred in 18 of 155 patients (12%). Pressure increases occurred in ten of 48 patients (21%) with a history of glaucoma; five of 24 patients (21%) undergoing combined penetrating keratoplasty, extracapsular cataract extraction, and posterior chamber intraocular lens implantation; and ten of 43 patients (23%) undergoing vitrectomy at the time of penetrating keratoplasty.

Aqueous Tube-shunt Implantation and Pars Plana Vitrectomy in Eyes With Refractory Glaucoma

We reviewed the surgical outcome of 20 eyes of 20 consecutive patients who had undergone combined aqueous tube-shunt implantation and vitrectomy for complicated glaucoma associated with vitreoretinal disorders. After a mean follow-up of 10.39 +/- 5.43 months, visual acuity remained stable or improved in 13 patients (65%), and intraocular pressure was controlled (< 22 mm Hg) in 15 (75%). The most common complications were corneal edema (seven eyes) and choroidal effusion (three eyes). Combined tube-shunt implantation and pars plana vitrectomy may successfully control intraocular pressure and maintain preoperative visual acuity in refractory glaucoma associated with vitreoretinal disorders.

Primary Trabeculectomy in Young Adults

BACKGROUND Younger patients are thought to have a poor surgical prognosis after trabeculectomy. The authors investigate the surgical outcome of young adult patients after primary trabeculectomy. METHODS The authors reviewed the charts of all patients 15 to 40 years of age who had undergone primary trabeculectomy without the use of antimetabolites between January 1985 and January 1992 at Wills Eye Hospital. Failure was defined before the data collection as intraocular pressure (IOP) more than 25 mmHg without medication, IOP more than 21 mmHg with medication, or when further glaucoma surgery was indicated. Patients in whom preoperative IOPs were 21 mmHg or lower were classified as successes when the IOP was reduced by at least 33% of the preoperative measurement. RESULTS After a mean follow-up of 36.8 +/- 21.8 months, among the 31 patients with uncomplicated glaucomas (juvenile, pigmentary, low tension, chronic angle closure), 26 (83.9%) were considered successes. After a mean follow-up of 42.3 +/- 26.5 months, among the 11 patients with other types of glaucoma (inflammatory, traumatic, associated with irido-corneal endothelial syndrome or mesodermal dysgenesis), 7 (63.6%) were considered successes. CONCLUSIONS The success rate of the uncomplicated group compares favorably with the 75% to 90% success rates of trabeculectomy commonly cited for primary glaucomas in older patients. Primary trabeculectomy in young adults may have a favorable outcome despite no antimetabolite therapy.

Color Doppler imaging in glaucoma patients with asymmetric optic cups.

To evaluate the color Doppler imaging (CDI) parameters of the retrobulbar circulation, we performed color Doppler imaging in both eyes of 29 glaucomatous patients with asymmetric cups [asymmetry >0.3 cup/disc ratio (C/D)] and asymmetric visual field loss. We used the QAD-1 Color Doppler unit (Quantum Medical Systems Inc.) with a 7.5-MHz linear-phased transducer to calculate the pulsatility index, and the peak systolic, end diastolic, and average blood-flow velocities in the ophthalmic, central retinal, nasal, and temporal short posterior ciliary arteries of each eye. In a second analysis, we compared the results of a randomly selected eye of age- and sex-matched controls. Paired t tests did not show any significant difference between the blood-flow velocities of the more damaged and less damaged eyes when the entire 29-patient group was considered together. The power was adequate to detect a 1.0 cm/s difference in most of the analyzed vessels. Thirteen of the 29 patients had primary open-angle glaucoma (POAG), and the remaining eyes had pseudoexfoliation and low tension, pigmentary, and chronic angle-closure glaucoma. When compared to age- and sex-matched controls, the less damaged eyes of patients with POAG displayed reduced systolic, diastolic, and mean velocities (p < 0.05) in the ophthalmic artery. In comparison, the more damaged eyes revealed statistically reduced velocities in the ophthalmic artery, temporal short posterior ciliary artery, and in all the parameters for the mean values of the short posterior ciliary arteries (p < 0.05). More advanced optic nerve damage in patients with POAG correlated with more severe reductions of CDI parameters of the retrobulbar circulation of patients with asymmetric disease. Further clinical color Doppler correlations are now mandatory to determine whether these vascular changes are pathogenetically important or epiphenomena.

Relative Optic Cup Depth Assessments Using Three Stereo Photograph Viewing Methods

PurposeA consistent stereoscopic (stereo) effect in disc photographs is important to be certain that apparent depth changes are real and are not the result of artifact caused by a variable stereo angle. The purpose of this study is to compare the accuracy of relative depth assessments using three different stereo photo viewing methods. MethodsWe evaluated the ability of 12 observers to arrange sets of simultaneous stereo photographs (Nidek 3-Dx split-frame slides, Lentec transparencies) and sequential stereo photographs (Zeiss full-frame slides) according to apparent cup depth. Observer arrangements of each set of 10 photographs were compared to a “reference standard” sequence determined from cup depth measurements made by the Imagenet optic nerve analyzer. ResultsThe median number of sequence errors (n = 6) made by all examiners in arranging the Nidek 3-Dx simultaneous stereo slides was significantly lower than the median number of errors (n = 12) with the Zeiss sequential stereo slides. ConclusionsSimultaneous stereo slides provide significantly more interobserver consistency for judgements of cup depth than sequential stereo slides.