Gregg Heatley

Comparison of the Ahmed Glaucoma Valve, the Krupin Eye Valve with Disk, and the double-plate Molteno implant.

ObjectiveTo compare the efficacy of the nonvalved double-plate Molteno implant with two valved implants, the Krupin Eye Valve with Disc and the Ahmed Glaucoma Valve, in the treatment of recalcitrant glaucoma. Patients and MethodsThe authors performed a nonrandomized retrospective review of patients who received the Molteno implant (n = 27), Krupin Eye Valve with Disc (n = 13), or Ahmed Glaucoma Valve (n = 13), with adjunctive mitomycin C. ResultsKaplan-Meier life-table analysis showed that the Molteno implant patients were more likely to maintain an intraocular pressure between 5 and 15 mm Hg than Ahmed Glaucoma Valve patients (P = 0.03). Success rates at 1 year were 80% (95% CI, 66–97%) for the Molteno implant, 39% (19–77%) for the Krupin Eye Valve with Disc, and 35% (15–82%) for the Ahmed Glaucoma Valve. However, Ahmed Glaucoma Valve patients were less likely to experience complications requiring reoperation or loss of two or more lines of visual acuity (P < 0.01) than Molteno implant or Krupin Eye Valve with Disc patients. ConclusionsThis nonrandomized study suggests that the Molteno implant with mitomycin C is more likely to result in intraocular pressures in the lower teens than the Ahmed Glaucoma Valve with mitomycin C. The findings suggest that the Ahmed implant is less likely to create problems leading to reoperations or visual acuity loss than the Molteno or Krupin implants.

Trabeculectomy with Mitomycin C: Intermediate-Term Results

PURPOSE This study was performed to provide results 2 to 3 years after trabeculectomy with mitomycin C (MMC). METHODS A consecutive series of all 68 patients who underwent trabeculectomy with MMC was analyzed using Kaplan-Meier life-table statistics and compared with other published retrospective analyses. RESULTS At 2- and 3-year follow-up examinations, 59% (95% confidence interval [CI], 44-70%) and 47% (95% CI, 32-61%) of patients, respectively, avoided an intraocular pressure (IOP) of more than 21 mmHg or less than 20% below their preoperative level without glaucoma medication on two consecutive occasions more than 1 month apart after 3 months follow-up (75% [95% CI, 60-84%] and 70% [95% CI, 53-81%], respectively, with medication) and avoided additional glaucoma surgery. Loss of more than three lines of visual acuity on two occasions more than 1 month apart after 3 months follow-up occurred in 28% of patients (> 2 lines in 44%) at 3 years. Nonreversible causes of loss of three lines of acuity occurred in 13% of patients. Complications requiring reoperation occurred in 16% of patients and included hypotony maculopathy (4%) and late bleb leaks (4%). CONCLUSIONS At the 3-year follow-up evaluation, trabeculectomy with MMC provided an approximately 50% chance of maintaining IOPs less than 21 mmHg and a more than 20% IOP reduction without concomitant use of glaucoma medication, which increased to 70% with the addition of medication. This procedure was associated with an approximately 30% risk of substantial visual loss (approximately 15% nonreversible) and a 15% chance of reoperation for complications.

Surgical intervention and accommodative responses, II: forward ciliary body accommodative movement is facilitated by zonular attachments to the lens capsule.

PURPOSE To determine the role of the lens and the lens capsule in the three-dimensional architecture of the ciliary muscle at rest and during accommodation, in live rhesus monkeys and in histologic sections, by removing the entire lens, or only the lens nucleus and cortex, while leaving the posterior capsule in place. METHODS In 15 rhesus monkey eyes, aged 6 to 27 years, accommodation was induced by central stimulation of the Edinger-Westphal nucleus before and after intra- or extracapsular lens extraction (ICLE, ECLE). Forward ciliary body movement and ciliary body width were measured by ultrasound biomicroscopy (UBM, 50 MHz). The monkeys were then killed, the eyes were examined morphologically in 1-microm sections, and the shape of the ciliary muscle was compared with that obtained from UBM images. RESULTS The shape of the ciliary muscle in eyes undergoing ECLE (n = 5) did not differ from that in control eyes. In contrast, after ICLE (n = 10), accommodative forward ciliary body movement (P < 0.01) and thickness were decreased (P < 0.001), length was increased (P = 0.058), and the inner apex was located more posteriorly than in control eyes (P < 0.005). Histologic and in vivo data were similar and showed that the ciliary muscle maintained its triangular shape only if the lens capsule (with or without the lens substance) was present. CONCLUSIONS The posterior lens capsule and anterior zonular attachments facilitate forward accommodative ciliary body movement. Lens substance extraction procedures that leave the posterior capsule intact, similar to those used clinically, do not affect the capsule/zonular/muscular system movements, an important finding for accommodating intraocular lens development.

Surgical Intervention and Accommodative Responses, I: Centripetal Ciliary Body, Capsule, and Lens Movements in Rhesus Monkeys of Various Ages

PURPOSE To determine how surgically altering the normal relationship between the lens and the ciliary body in rhesus monkeys affects centripetal ciliary body and lens movement. METHODS In 18 rhesus monkey eyes (aged 6-27 years), accommodation was induced before and after surgery by electrical stimulation of the Edinger-Westphal nucleus. Accommodative amplitude was measured by coincidence refractometry. Goniovideography was performed before and after intra- and extracapsular lens extraction (ICLE, ECLE) and anterior regional zonulolysis (ARZ). Centripetal lens/capsule movements, centripetal ciliary process (CP) movements, and circumlental space were measured by computerized image analysis of the goniovideography images. RESULTS Centripetal accommodative CP and capsule movement increased in velocity and amplitude after, compared with before, ECLE regardless of age (n = 5). The presence of the lens substance retarded capsule movement by approximately 21% in the young eyes and by approximately 62% in the older eyes. Post-ICLE compared with pre-ICLE centripetal accommodative CP movement was dampened in all eyes in which the anterior vitreous was disrupted (n = 7), but not in eyes in which the anterior vitreous was left intact (n = 2). After anterior regional zonulolysis (n = 4), lens position shifted toward the lysed quadrant during accommodation. CONCLUSIONS The presence of the lens substance, capsule zonular attachments, and Wiegers ligament may play a role in centripetal CP movement. The capsule is still capable of centripetal movement in the older eye (although at a reduced capacity) and may have the ability to produce approximately 6 D of accommodation in the presence of a normal, young crystalline lens or a similar surrogate.

Accommodative movements of the lens/capsule and the strand that extends between the posterior vitreous zonule insertion zone & the lens equator, in relation to the vitreous face and aging.

To elucidate the dynamic accommodative movements of the lens capsule, posterior lens and the strand that attaches to the posterior vitreous zonule insertion zone and posterior lens equator (PVZ INS‐LE), and their age‐related changes.

The rarity of clinically significant rise in intraocular pressure after laser peripheral iridotomy with apraclonidine

OBJECTIVE To determine the incidence of intraocular pressure (IOP) rise of varying degrees after laser peripheral iridotomy (LPI) in patients with and without glaucoma treated perioperatively with pilocarpine and apraclonidine. DESIGN A retrospective chart review. PARTICIPANTS A total of 289 eyes in 179 patients with narrow occludable angles (NOA) (N = 148), open-angle glaucoma or ocular hypertension (OAG) (N = 115), or chronic-angle closure glaucoma (CACG) (N = 26) were reviewed. MAIN OUTCOME MEASURES The difference between preoperative and postoperative IOP, absolute postoperative IOP, and the need for acute IOP-lowering treatment was noted. RESULTS Only 1.1% (95% confidence interval [CI], 0.03%-5.8%; 1 of 94) of patients and 0.7% (95% CI, 0.02%-3.7%; 1 of 148) of eyes with NOA experienced a rise of more than 10 mmHg 1 to 2 hours after LPI. The incidence of postoperative IOP greater than 25 mmHg and acute postoperative IOP-lowering management was 0% (95% CI, 0%-3.8%). Intraocular pressure in 1 of 115 eyes (0.9%, 95% CI, 0.02%-4.7%) with OAG rose more than 10 mmHg, requiring acute treatment. None of the 26 CACG eyes experienced a rise of more than 10 mmHg (95% CI, 0%-13.2%). CONCLUSION The IOP rise that requires further intervention after LPI with the perioperative use of pilocarpine and apraclonidine is very uncommon. In patients with NOA, routine postiridotomy IOP monitoring may not be required.

Effect of H-7 on Secondary Cataract After Phacoemulsification in the Live Rabbit Eye

PURPOSE This study is aimed to determine if the serine-threonine kinase inhibitor H-7 inhibits secondary cataract after phacoemulsification in the live rabbit eye. METHODS Eighteen rabbits underwent extracapsular lens extraction by phacoemulsification in 1 eye. The eye was treated with intravitreal H-7 (300 or 1,200 μM; n = 6 or 5) or balanced salt solution (BSS) (n = 7) immediately after the surgery and twice weekly for 10 weeks. Each eye received slit lamp biomicroscopy once a week, during which posterior capsule opacification (PCO) was evaluated. The eye was then enucleated and the lens capsule was prepared, fixed, and imaged. PCO was evaluated again on the isolated lens capsule under a phase microscope. Soemmerings ring area (SRA) and the entire lens capsule area were measured from capsule images on a computer and the percentage of SRA (PSRA) in the entire capsule area was calculated. Wet weight of the capsule (WW) was determined on a balance. RESULTS No significant difference in PCO was observed in any comparison. No significant differences in SRA, PSRA, and WW were observed between the 300 μM H-7-treated eye and the BSS-treated eye. However, SRA, PSRA, and WW in the 1,200 μM H-7-treated eye were significantly smaller than those in the BSS-treated eye [28.3 ± 16.2 vs. 61.4 ± 8.86 mm(2) (P = 0.001), 33% ± 20% vs. 65% ± 15% (P = 0.01), and 65.6 ± 27.9 vs. 127.0 ±37.3 mg (P = 0.01)]. CONCLUSIONS Intravitreal H-7 (1,200 μM) significantly inhibits Soemmerings ring formation in the live rabbit eye, suggesting that agents that inhibit the actomyosin system in cells may prevent secondary cataract after phacoemulsification.

Something Old (Trabeculectomy), Something New (Ab Interno Gelatin Microstent): Finally, a Marriage of Innovation and Outcome Data (without Concurrent Cataract Surgery)!

We thank Schlenker et al (see http://www.aaojournal.org/ article/S0161-6420(17)30464-5/fulltext) for providing a much-needed substantive comparison of one of the newer less-invasive glaucoma procedures (ab interno gelatin microstent) with trabeculectomy, the gold standard glaucoma filtering procedure for nearly 50 years. We have all been seeking a more predictable and successful treatment than trabeculectomy, and our patients are potential beneficiaries of a surge of innovation exploring techniques and devices to afford enhanced aqueous outflow via Schlemm canal, suprachoroidal, and subconjunctival approaches. The Food and Drug Administration-approved devices in the 2 former categories have been studied and approved in the context of combination treatment with cataract surgery. Partly because of the intraocular pressure (IOP) reduction achieved by cataract surgery alone, the seminal studies for those devices in combination with cataract surgery have demonstrated only modestly greater reduction in IOP, ocular hypotensive medication burden, or both than cataract surgery alone. Furthermore, the IOP outcomes have clustered in the mid to high teens in most patients, such that many patients for whom lower IOPs are desirable may not be sufficiently well served by those devices. Because both of us are somewhat skeptical by nature (one of us by virtue being sufficiently senior to have personally lived through Scott’s parabola with such devices as the Mendez Glaucoma Seton, Krupin-Denver valve, thulium-holmium-chromium-doped:yttriumealuminume garnet laser sclerostomy, and Ex-PRESS (Optonol, Ltd., Neve-Ilan, Israel) implant [not under scleral flap]), we enthusiastically welcome the retrospective comparison by Schlenker et al of the ab interno gelatin microstent and trabeculectomy without the confounding variable of cataract surgery. The authors exhibit considerable understanding of clinical research, as well as very sophisticated and effective application of statistical methods. We wish that, as soon as the authors had achieved reasonable facility and comfort with the microstent procedure, they had seized the opportunity to undertake a randomized clinical trial (RCT) for a more direct comparison. Too frequently, the early adopters among us perform relatively high volumes of a new procedure without subjecting that procedure to the rigors of an RCT, from which fellow physicians would derive invaluable insight into the relative merits of and indications for that procedure versus an appropriate gold standard. Retrospective cohort studies are certainly informative, but RCTs minimize bias, especially in patient

Effects of Vitrectomy and Lensectomy on Older Rhesus Macaques: Oxygen Distribution, Antioxidant Status, and Aqueous Humor Dynamics

Purpose The purpose of this study is to evaluate effects of vitrectomy (PPV) and lens extraction with intraocular lens implantation (PE/IOL) on molecular oxygen (pO2) distribution, aqueous humor antioxidant–oxidant balance, aqueous humor dynamics, and histopathologic changes in the trabecular meshwork (TM) in the older macaque monkey. Methods Six rhesus monkeys underwent PPV followed by PE/IOL. pO2, outflow facility, and intraocular pressure (IOP) were measured. Aqueous and vitreous humor specimens were analyzed for antioxidant status and 8-hydroxy-2′-deoxyguanosine (8-OHdG), a marker of oxidative damage. TM specimens were obtained for immunohistochemical and quantitative PCR analysis. Results pO2 at baseline revealed steep gradients in the anterior chamber and low levels in the posterior chamber (PC) and around the lens. Following PPV and PE/IOL, pO2 significantly increased in the PC, around the IOL, and angle. IOP increased following both surgical interventions, with no change in outflow facility. Histopathologic analysis did not show changes in TM cell quantification, but there was an increase in 8-OHdG. Quantitative PCR did not reveal significant differences in glaucoma-related gene expression. Aqueous and vitreous humor analysis revealed decreased ascorbate and total reactive antioxidant potential and increased 8-OHdG in the aqueous humor only in the surgical eyes. Conclusions Oxygen distribution in the older rhesus monkey is similar to humans at baseline and following surgical interventions. Our findings of histopathologic changes of TM oxidative damage and alterations in the oxidant-antioxidant balance suggest a potential correlation of increased oxygen exposure with oxidative stress/damage and the development of open angle glaucoma.

Pharmacology of Glaucoma

Few areas of ophthalmology are changing as fast as the diagnosis and treatment of glaucoma. Pharmacology of Glaucoma is an update of the 1983 version, which was a summary of a meeting held to celebrate the opening of the Eye Care Centre in British Columbia. On Drances recent retirement from heading the department there, he believed it fitting to update the information on these topics to reflect the gains in knowledge made in this field over the intervening 9 years. As such, this text is an attempt to summarize the current status of medical treatment research for glaucoma as well as to share some vision of the future and what form the next decade of advances will take. The level of the text is aimed at the basic science researcher and/or astute clinician, and clearly is not intended for those new to glaucoma. The first few chapters discuss surgical pharmacology,