Education Outcomes from an Ophthalmology Microsurgery Course for Medical Students

Journal of Academic Ophthalmology · 2025-08-14

Background: Microsurgery training programs are critical for developing the skills needed by ophthalmology residents, but they are not typically offered to medical students. However, incorporating a microsurgery course into medical school curricula may help students more carefully consider a career in ophthalmology and improve learning outcomes during their training. Purpose: This article describes a microsurgery course for medical students and evaluates its educational impact. Methods: A microsurgery course was developed and implemented for third (MS3) and fourth (MS4) year medical students at Duke University School of Medicine. The fourweek course included six didactic lectures, three hands-on skills sessions, and the use of a dissection microscope for home practice. Participant knowledge and suturing skills were measured at the course's beginning and end via a written assessment and a timed suturing challenge. Results were analyzed using SAS/STAT software. Results: Fifteen students participated in the microsurgery course, including eight MS3 and seven MS4 students. Participants showed significant improvements in microsurgical skills, measured by count, quality, and self-reported confidence during the suturing challenge. They also showed significant improvement in their knowledge of microsurgical techniques, as measured by written assessment scores. There was no significant difference between MS3 and MS4 students. Additionally, there was no correlation between final written assessment scores and the final number of sutures. Conclusion: Medical students participating in this microsurgical curriculum in its entirety improved their skills and knowledge, providing an example of how an affordable educational program can deepen instruction and engage future ophthalmologists even during their pre-residency medical training.

The Efficacy and Safety of Trabeculectomy after Failed Primary Glaucoma Drainage Devices

Ophthalmology and Therapy · 2025-06-22

INTRODUCTION: Trabeculectomy is not usually considered for uncontrolled intraocular pressure (IOP) after glaucoma drainage devices (GDD) because of concern that the conjunctiva has been violated and future trabeculectomy surgery is likely to fail due to fibrosis. We examined the clinical outcomes of patients who underwent a trabeculectomy after failed primary GDD. METHODS: This is a cross-sectional study of all patients who had a glaucoma drainage implant that failed or was inadequate in lowering IOP and underwent a trabeculectomy in the same eye from January 2016 to December 2022. RESULTS: A total of 23 eyes in 22 patients met our criteria. Average IOP [± standard deviation (SD)] prior to trabeculectomy was 21.7 ± 9.3 on 3.2 ± 1.3 medications. The length of follow-up was between 0.3 and 5.0 years with an average follow-up time of 2.2 years. At 1 year (n = 16), IOP was 11 ± 1.9 mm Hg on 1.8 ± 1.5 medications. At 2 years, the average IOP was 11.8 ± 4.6 on 1.9 ± 1.4 medications. At all follow-up points, the decrease in IOP and medication was statistically significant compared with baseline (paired t-tests; p < 0.05). Most postoperative complications self-resolved with medical management (three early wound leaks, two late wound leaks, two instances of hypotony maculopathy, and one instance of cystoid macular edema). One early wound leak required surgical repair. One eye underwent an additional GDD surgery, and three eyes underwent bleb needling. In all, 20 (87%) eyes at final visit were within two lines of their baseline vision prior to trabeculectomy. No eyes progressed to having no light perception visual acuity or had an ocular infection. CONCLUSIONS: This study suggests that trabeculectomy after a GDD is an effective and safe option for IOP control and glaucoma medication reduction. In this small sample of surgical cases, complication and reoperation rates were comparable to published rates.

The Duke Baerveldt 350 Versus Ahmed ClearPath 350 Study (DBACS): A Randomized Control Trial In Adults With Medically Refractory Glaucoma

Clinical ophthalmology · 2025-09-01 · 1 citations

Purpose: To compare the efficacy and safety profile of two non-valved glaucoma drainage devices (GDDs). Patients & Methods: In this randomized control trial, patients with medically refractory glaucoma needing surgical intervention were randomized for placement of a Baerveldt 350 (BVT) or an Ahmed ClearPath 350 (ACP). Baseline testing included measures of visual acuity, intraocular pressure (IOP), medication, visual fields, and optical coherence tomography. IOP, medication use, and complications were assessed at post-operative day one, week one, week four, week six, month three, month six, and year one. Results: A total of 76 subjects were enrolled, 37 randomized to BVT and 39 to ACP. A total of 70 subjects underwent surgery and 61 subjects were seen to one year of follow-up. No significant differences were observed in age, sex, race, eye laterality, glaucoma type, glaucoma severity, prior surgeries, and baseline IOP (p = 0.66, 0.10, 0.70, 0.48, 0.06, 0.65, 0.50, 0.56 respectively), between the groups. At one year, both groups showed significant reductions in IOP, though the ACP group showed lower mean IOP at 12 months (11.4 vs 14.1 mmHg, p = 0.010) as well as a larger IOP decrease compared to baseline (-44.1 vs -30.7%, p = 0.038). Medication usage remained similar in both groups. Complications were infrequent and comparable between the devices. This study did not reach the number of subjects thought to be needed to power the study appropriately; despite the enrollment numbers, statistically significant differences were noted, and no type II occurred for the primary endpoint of mean IOP. Conclusion: While both GDDs demonstrated efficacy over a 1-year period, ACP showed a lower mean IOP and greater IOP percentage decrease from baseline compared to BVT. Both exhibited low complication rates. Further research over a longer follow-up is warranted to explore the IOP differences.

Valve-Like Outflow System Behavior With Motion Slowing in Glaucoma Eyes: Findings Using a Minimally Invasive Glaucoma Surgery–MIGS-Like Platform and Optical Coherence Tomography Imaging

Frontiers in Medicine · 2022-04-29 · 11 citations

Purpose This study aimed to investigate anatomic relationships and biomechanics of pressure-dependent trabecular meshwork and distal valve-like structure deformation in normal and glaucoma eyes using high-resolution optical coherence tomography (HR-OCT). Methods We controlled Schlemm’s canal (SC) pressure during imaging with HR-OCT in segments of three normal (NL) and five glaucomatous (GL) ex vivo eyes. The dissected limbal wedges were studied from 15 locations (5 NL and 10 GL). A minimally invasive glaucoma surgery (MIGS)-like cannula was inserted into the SC lumen, whereas the other end was attached to a switch between two reservoirs, one at 0, the other at 30 mm Hg. A steady-state pressure of 30 mm Hg was maintained to dilate SC and collector channels (CC) during 3D volume imaging. The resulting 3D lumen surface relationships were correlated with internal structural features using an image mask that excluded tissues surrounding SC and CC. While imaging with HR-OCT, real-time motion responses in SC and CC areas were captured by switching pressure from 0 to 30 or 30 to 0 mm Hg. NL vs. GL motion differences were compared. Results Lumen surface and internal relationships were successfully imaged. We identified SC inlet and outlet valve-like structures. In NL and GL, the mean SC areas measured at the steady-state of 0 and 30 mm Hg were each significantly different ( p &amp;lt; 0.0001). Synchronous changes in SC and CC lumen areas occurred in &amp;lt;200 ms. Measured SC area differences at the steady-state 0 and 30 mmHg, respectively, were larger in NL than GL eyes ( p &amp;lt; 0.0001). The SC motion curves rose significantly more slowly in GL than NL ( p &amp;lt; 0.001). Pressure waves traveled from the cannula end along the SC lumen to CC and deep intrascleral channels. Conclusion HR-OCT provided simultaneous measurements of outflow pathway lumen surfaces, internal structures, and biomechanics of real-time pressure-dependent dimension changes. We identified SC inlet and outlet valve-like structures. GL tissues underwent less motion and responded more slowly than NL, consistent with increased tissue stiffness. A MIGS-like shunt to SC permitted pulse waves to travel distally along SC lumen and into CC.

Detecting disease progression in mild, moderate and severe glaucoma

Current Opinion in Ophthalmology · 2022-11-07 · 3 citations

PURPOSE OF REVIEW: The purpose of this review is to examine contemporary techniques for detecting the progression of glaucoma. We provide a general overview of detection principles and review evidence-based diagnostic strategies and specific considerations for detecting glaucomatous progression in patients with mild, moderate and severe disease. RECENT FINDINGS: Diagnostic techniques and technologies for glaucoma have dramatically evolved in recent years, affording clinicians an expansive toolkit with which to detect glaucoma progression. Each stage of glaucoma, however, presents unique diagnostic challenges. In mild disease, either structural or functional changes can develop first in disease progression. In moderate disease, structural or functional changes can occur either in tandem or in isolation. In severe disease, standard techniques may fail to detect further disease progression, but such detection can still be measured using other modalities. SUMMARY: Detecting disease progression is central to the management of glaucoma. Glaucomatous progression has both structural and functional elements, both of which must be carefully monitored at all disease stages to determine when interventions are warranted.

Using Fixed-Force Goldmann Applanation Tonometry to measure the Ocular Pulse Amplitude

Investigative Ophthalmology & Visual Science · 2021-06-21

Cataract Surgery Is Not Associated with Decreased Risk of Retinal Vein Occlusion

Ophthalmology Science · 2021-07-14 · 8 citations

Purpose: To evaluate whether cataract surgery is associated with decreased risks of central retinal vein occlusion (CRVO) or branch retinal vein occlusion (BRVO) development using the American Academy of Ophthalmology Intelligent Research in Sight (IRIS®) Registry. Design: Retrospective database study of the IRIS Registry data. Participants: Patients in the IRIS Registry who underwent cataract surgery and 1:1 matched control participants from the IRIS Registry using a decision tree classifier as a propensity model. Methods: Control and treatment groups initially were selected using Current Procedural Terminology codes for uncomplicated cataract surgery and other straightforward criteria. To accomplish treatment-control matching, a decision tree classifier was trained to classify patients as treatment versus control based on a set of chosen predictors for treatment, where best-corrected visual acuity and age were the most important predictors. Treatment and control participants subsequently were matched using the classifier, the visit dates, and the identifications of the practice. Cox regression was performed on the matched groups to measure the hazard ratio (HR) of retinal vein occlusion development adjusted for age, sex, race, primary insurance type, and previous diagnosis of diabetic retinopathy (DR), glaucoma, and narrow angles. Main Outcome Measure: The HR of retinal vein occlusion developing in patients who underwent cataract surgery compared with matched control participants. Results: < 0.001]) development after cataract surgery. Conclusions: Cataract surgery is associated with a small increase in risk of retinal vein occlusions within the first year; however, the incidence is low and likely not clinically significant.

Aqueous outflow regulation – 21st century concepts

Publisher · 2021-07-01 · 4 citations

We propose an integrated model of aqueous outflow control that employs a pump-conduit system in this article. Our model exploits accepted physiologic regulatory mechanisms such as those of the arterial, venous, and lymphatic systems. Here, we also provide a framework for developing novel diagnostic and therapeutic strategies to improve glaucoma patient care. In the model, the trabecular meshwork distends and recoils in response to continuous physiologic IOP transients like the ocular pulse, blinking, and eye movement. The elasticity of the trabecular meshwork determines cyclic volume changes in Schlemm's canal (SC). Tube-like SC inlet valves provide aqueous entry into the canal, and outlet valve leaflets at collector channels control aqueous exit from SC. Connections between the pressure-sensing trabecular meshwork and the outlet valve leaflets dynamically control flow from SC. Normal function requires regulation of the trabecular meshwork properties that determine distention and recoil. The aqueous pump-conduit provides short-term pressure control by varying stroke volume in response to pressure changes. Modulating TM constituents that regulate stroke volume provides long-term control. The aqueous outflow pump fails in glaucoma due to the loss of trabecular tissue elastance, as well as alterations in ciliary body tension. These processes lead to SC wall apposition and loss of motion. Visible evidence of pump failure includes a lack of pulsatile aqueous discharge into aqueous veins and reduced ability to reflux blood into SC. These alterations in the functional properties are challenging to monitor clinically. Phase-sensitive OCT now permits noninvasive, quantitative measurement of pulse-dependent TM motion in humans. This proposed conceptual model and related techniques offer a novel framework for understanding mechanisms, improving management, and development of therapeutic options for glaucoma.

Automated Detection of Glaucoma With Interpretable Machine Learning Using Clinical Data and Multimodal Retinal Images

American Journal of Ophthalmology · 2021 · 109 citations

• Computer Science
• Artificial Intelligence
• Computer Science

Macular vascular microcirculation in the ganglion cell-inner plexiform layer in glaucoma patients of African and European descent using optical coherence tomography angiography

Investigative Ophthalmology & Visual Science · 2020-06-10