Gonioscopy and Angle-Based Glaucoma Surgical Training on Human Eyes in the Wet Lab.

PRCIS: Human corneoscleral rims provide a low cost model and resource to enhance angle based glaucoma surgical training skills. PURPOSE: To understand the feasibility, utility, and efficacy of a low-cost model for performing anterior chamber angle gonioscopy and micro-surgery on human corneoscleral tissues in wet lab on resident skill enhancement. METHODS: Post-keratoplasty residual corneoscleral rims and/or the expired donor corneoscleral buttons were included for the purpose of this study. Initially, inverted rims were used to demonstrate the basic angle anatomy on a slit lamp bio-microscope. Central hazy cornea was then replaced with an artificial cornea and an artificial anterior chamber to simulate indirect gonioscopy, direct gonioscopy, goniotomy, and other angle-based surgeries. Direct gonioscopy and goniotomy exercises (as a means to simulate intraoperative gonioscopy and other angle-based surgeries respectively) were evaluated quantitatively, and the rest qualitatively. RESULTS: A total of 65 residents were included in the exercise. The mean age was 26.69±1.74 years. Amongst these, 55 ophthalmology residents performed the basic examination, that is, slit lamp mounted angle anatomy examination (n=55) and artificial chamber mounted indirect gonioscopic examination through artificial cornea (n=55). In the second exercise, 10 glaucoma fellows performed the direct gonioscopic and the goniotomy exercises on artificial chamber. The fellows demonstrated a statistically significant improvement in interpretation and surgical skill enhancement concurrent with reduction in time taken with increasing number of attempts ( P <0.05). In the third simulation exercise, micro-stent placement within the Schlemm's canal, subconjunctival space, and the suprachoroidal space was re-produced successfully on multiple occasions. CONCLUSIONS: The residual human corneoscleral rims proved to be an important resource for teaching both the basic examination skills and those required for transitioning to advanced intraoperative gonioscopy and goniotomy skills. These low cost, easy to adapt models can be incorporated within the curriculum for improved glaucoma training of both the residents and the glaucoma fellows.

Trabeculectomy on Animal Eye Model for Resident Surgical Skill Training: The Need of the Hour.

Purpose: To describe a goats' eye training model for teaching of trabeculectomy and releasable suture techniques for Ophthalmology residents. Methods: A descriptive report explaining the methodology for setting up a goats' eye wet-lab model for teaching trabeculectomy for Ophthalmology residents. It details the approaches to eyeball preparation, steps of surgery, application and release of two representative types of 'releasable sutures' in a step-by-step manner. Conclusion: A systematic approach using goats' eye model to teach trabeculectomy and releasable suture techniques can enhance residents' understanding, confidence and expertise to operate upon human eyes.

Outcomes of trabecular microbypass surgery: Comparison of resident trainees and attending surgeons.

PURPOSE: To determine the efficacy, safety, and surgical outcomes of trabecular microbypass stent (iStent) surgery performed by resident trainees and attending surgeons. SETTING: Wills Eye Hospital, Philadelphia, Pennsylvania, USA. DESIGN: Retrospective case series. METHODS: Records of all patients who had microbypass stent surgery by a resident at Wills Eye Hospital were retrospectively reviewed. The attending-performed group included any patient who had a microbypass stent implanted by an attending surgeon on the same day a resident case was performed. RESULTS: Between 2016 and 2018, 31 microbypass stents were implanted by a resident supervised by an attending and 93 microbypass stents were implanted by an attending surgeon on the day a resident case was performed. The mean follow-up was 16.2 months ± 17.9 (SD). The mean intraocular pressure (IOP) decreased from 16.0 ± 4.6 mm Hg at baseline to 14.0 ± 3.1 mm Hg at most recent follow-up visit in the resident group (P = .02) and from 17.5 ± 4.8 mm Hg to 15.1 ± 4.3 mm Hg, respectively, in the attending group (P < .001). The final mean IOP and mean number of hypotensive medications were similar between the 2 groups (P = .83 and P = .12, respectively). Self-resolving hyphema occurred in 1 resident case and 2 attending cases. The resident group had 1 case of iridodialysis, which did not require additional surgery. One eye in the attending group ultimately required a trabeculectomy. CONCLUSION: Microbypass stent implantation by resident trainees with attending supervision had similar efficacy and safety as surgery performed by attending surgeons.

K-RIM (Corneal Rim) Angle Surgery Training Model.

PURPOSE: To develop an angle surgery training model for training an array of microincisional glaucoma surgery (MIGS) procedures. METHODS: We describe a method for preparing an angle surgery training model using human cadaveric corneoscleral rims. The model provides realistic tactile tissue simulation and excellent angle visualization requiring bimanual technique. Corneoscleral rims may be used multiple times and are prepared at low cost, allowing for a high volume of practice surgeries. RESULTS: This model allows for practice in bimanual surgical training using the gonioscopy lens for visualize alongside surgical tools. The in vivo surgical conditions and limited tactile feedback are recreated using human cadaveric eyes which nonhuman models fail to provide. Our model is prepared at low cost, with relative ease and also provides appropriate positioning of Schlemm canal and for high volume of practice as the canal can be used in 90-degree segments. CONCLUSIONS: Few angle surgery training models currently exist and none provide these necessary features. The model presented here aims to meet the growing demand for adequate training models required for technically advanced MIGS techniques.

Competency-Based Education Assessment Tools for Laser Capsulotomy, Peripheral Iridotomy, and Selective Laser Trabeculoplasty.

PURPOSE: To produce Competency-Based Education Assessment Tools (C-BEAT) for performance of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy, laser peripheral iridotomy (LPI), and selective laser trabeculoplasty (SLT) on an artificial eye model that can be used in competency-based medical education (CBME) of ophthalmology residents. DESIGN: Survey. PARTICIPANTS: Eight content experts (residency program director and faculty members involved in ophthalmology resident training). METHODS: Task-specific checklists were created to assess the performance of Nd:YAG capsulotomy, LPI, and SLT on artificial eye models designed for each of these procedures, as well as a global rating scale (GRS). A modified Delphi process was used to establish face and content validity of the C-BEAT for lasers. Eight content experts participated in the Delphi process, and the consensus was achieved after 4 rounds. MAIN OUTCOME MEASURE: Survey responses. RESULTS: Final versions of checklists for Nd:YAG capsulotomy, LPI, and SLT, and a GRS for these laser procedures were produced with face and content validity. Modifications to the energy settings and the number of applications in the capsulotomy and peripheral iridotomy were implemented into the checklist and instructions, because the artificial models were not identical in their responses to the laser applications compared with real tissue. CONCLUSIONS: The C-BEAT for lasers can be used in an examination setting within ophthalmology residency training programs to establish competency in these procedures before performing them on real patients. These tools help to meet the demand for assessment modalities within a CBME model that is being implemented into residency training worldwide. To establish interrater and construct validities, further studies are required.

Cadaver corneoscleral model for angle surgery training.

PURPOSE: To assess a new training model (Tackdriver) for new-generation microinvasive glaucoma surgeries (MIGS). SETTING: Resident training centers in Canada. DESIGN: Evaluation of technology. METHODS: Human cadaver corneoscleral rims recovered after Descemet-stripping endothelial keratoplasty or not suitable for transplantation were acquired from an eye bank. The tissue was fixated with a single tack through the center of the cornea, which was inverted in a concave fashion. A water-based medical lubricant was used for placement of a goniolens after visualization of the anterior chamber and the trabecular meshwork. Microbypass stent (iStent) insertion and gonioscopy-assisted transluminal trabeculotomy (GATT) were practiced on this model. The model was qualitatively assessed for ease of preparation, accuracy of surgical simulation, and the number and variety of MIGS procedures that can be performed. RESULTS: Efficient high-volume training was performed for microbypass stent insertion using first-generation and second-generation microbypass stents. The GATT procedure was also performed as a final step in a titratable fashion in 90-, 180-, or 270-degree segments or a complete 360-degree treatment. The model simulated bimanual angle surgery with good fidelity. CONCLUSIONS: The training model allowed for high-volume bimanual MIGS training for techniques such as microbypass stent insertion and removal as well as GATT. Preparation was relatively simple, efficient, and cost-effective compared with other models. Inverting the specimen allowed the trainee to practice MIGS techniques independent of the tissue's corneal clarity. Other MIGS techniques and angle training procedures can be adopted to this model.

Trabeculectomy training in England: are we safe at training? Two year surgical outcomes.

OBJECTIVES: To define the safety profile of trainee trabeculectomy surgery in the United Kingdom. Surgical exposure for trainees in England is limited due to service requirements, the European working time directive constraints and increasing sub-specialisation of glaucoma surgery. Limited knowledge exists on the outcomes of supervised glaucoma surgery. The aim is to determine the safety of supervised trabeculectomy surgery performed by trainee ophthalmologists. METHODS: Retrospective case note review of all patients that had trabeculectomy surgery with MMC by consultant and trainee surgeons across multiple UK centres. All eyes have 2-year follow up. Success was determined using WGA guidelines. Two-tailed p values were obtained using Fisher's exact test to ascertain statistical significance between groups. MAIN OUTCOME MEASURES: intraocular pressure, visual acuity, success and failure rates. RESULTS: 324 eyes were reviewed. 211 (66.4%) cases were performed by glaucoma consultants, 107(33.6%) by trainee ophthalmologists. The majority of eyes in each group were undergoing surgery for POAG. Post-operative IOP control showed no significant difference between consultant and trainee groups at year 1 and year 2. Success rates showed no significant difference between consultant and trainee cases. Failure rates at year 1 showed a significant difference between the two groups. No significant difference was seen at year 2. The trainee group had significantly more complications, when compared with the consultant group. Snellen visual acuity loss was not statistically significant between the two groups at the 2 year time point. CONCLUSIONS: The outcomes of supervised trainee trabeculectomy compare favourably with consultant cases after 2 year follow up. Trainee cases had higher complication rates than consultant cases. Bleb leaks are a common complication of trainee cases, where closer supervision may be required. There is potential for surgical simulation to help increase the success of such cases. These findings may encourage trainee participation in glaucoma surgery.

The Ophthalmology Surgical Competency Assessment Rubric for Trabeculectomy.

PURPOSE: To produce an internationally valid tool to assess skill in performing trabeculectomy surgery. METHODS: A panel of 5 experts developed a tool for assessing trabeculectomy surgery by using a modified Dreyfus scale of skill acquisition and providing descriptors for each level of skill for each category. The tool was then reviewed by a panel of 10 international content experts for their constructive comments, which were incorporated into the final rubric tool. RESULTS: A final rubric, incorporating the suggestions of the international panel, published here as the ICO-OSCAR: Trabeculectomy. CONCLUSIONS: The tool ICO-OSCAR: Trabeculectomy has content and face validity. It can be used internationally to assess trabeculectomy surgery skill. Predictive and construct validity, and reliability are yet to be determined.

Rapid learning curve assessment in an ex vivo training system for microincisional glaucoma surgery.

Increasing prevalence and cost of glaucoma have increased the demand for surgeons well trained in newer, microincisional surgery. These procedures occur in a highly confined space, making them difficult to learn by observation or assistance alone as is currently done. We hypothesized that our ex vivo outflow model is sensitive enough to allow computing individual learning curves to quantify progress and refine techniques. Seven trainees performed nine trabectome-mediated ab interno trabeculectomies in pig eyes (n = 63). An expert surgeon rated the procedure using an Operating Room Score (ORS). The extent of outflow beds accessed was measured with canalograms. Data was fitted using mixed effect models. ORS reached a half-maximum on an asymptote after only 2.5 eyes. Surgical time decreased by 1.4 minutes per eye in a linear fashion. The ablation arc followed an asymptotic function with a half-maximum inflection point after 5.3 eyes. Canalograms revealed that this progress did not correlate well with improvement in outflow, suggesting instead that about 30 eyes are needed for true mastery. This inexpensive pig eye model provides a safe and effective microsurgical training model and allows objective quantification of outcomes for the first time.

Differential Canalograms Detect Outflow Changes from Trabecular Micro-Bypass Stents and Ab Interno Trabeculectomy.

Recently introduced microincisional glaucoma surgeries that enhance conventional outflow offer a favorable risk profile over traditional surgeries, but can be unpredictable. Two paramount challenges are the lack of an adequate training model for angle surgeries and the absence of an intraoperative quantification of surgical success. To address both, we developed an ex vivo training system and a differential, quantitative canalography method that uses slope-adjusted fluorescence intensities of two different chromophores to avoid quenching. We assessed outflow enhancement by trabecular micro-bypass (TMB) implantation or by ab interno trabeculectomy (AIT). In this porcine model, TMB resulted in an insignificant (p > 0.05) outflow increase of 13 ± 5%, 14 ± 8%, 9 ± 3%, and 24 ± 9% in the inferonasal, superonasal, superotemporal, and inferotemporal quadrant, respectively. AIT caused a 100 ± 50% (p = 0.002), 75 ± 28% (p = 0.002), 19 ± 8%, and 40 ± 21% increase in those quadrants. The direct gonioscopy and tactile feedback provided a surgical experience that was very similar to that in human patients. Despite the more narrow and discontinuous circumferential drainage elements in the pig with potential for underperformance or partial stent obstruction, unequivocal patterns of focal outflow enhancement by TMB were seen in this training model. AIT achieved extensive access to outflow pathways beyond the surgical site itself.

Trabeculectomy Outcomes by Supervised Trainees in a Veterans Affairs Medical Center.

PURPOSE: To evaluate the outcomes of trabeculectomy performed in an ophthalmology training program. DESIGN: Retrospective study. PARTICIPANTS: A total of 160 patients undergoing trabeculectomy performed by a resident or fellow under attending supervision. MATERIALS AND METHODS: Trabeculectomy surgeries performed by a supervised resident or fellow surgeon between October 2000 and April 2010 were reviewed. Success was considered to be complete or partial if intraocular pressure (IOP)-lowering medications were not or were required to achieve IOP≤21 mm Hg, respectively. Failure was defined as IOP>21 mm Hg on 2 consecutive visits, loss of light perception vision, IOP≤5 on 2 consecutive visits with associated visual acuity loss of ≥2 lines, or need for surgical intervention. Trabeculectomy survival was determined using Kaplan-Meier analysis through 60 months of follow-up. MAIN OUTCOME MEASURES: Final IOP, success/failure rate. RESULTS: Complete success was achieved in 65 patients (41%). The average final IOP of this group was 9.1±3.7 mm Hg. Qualified success was achieved in 56 patients (35%). The average final IOP of this group was 11.5±6.4 mm Hg. At 60 months, the estimated cumulative probability of survival for complete and qualified successes was 28.9% and 63.7%, respectively. CONCLUSIONS: Among patients undergoing trabeculectomy by supervised residents or glaucoma fellows in a large Veterans Affairs Medical Center, IOP reduction was significant and similar to published studies. Trabeculectomy remains a successful intervention to lower IOP, with satisfactory success rates in the hands of trainee surgeons.

A Comparison of Resident-performed Argon and Selective Laser Trabeculoplasty in Patients With Open-angle Glaucoma.

PURPOSE: To compare intraocular pressure (IOP) reduction and complications of resident-performed argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT). PATIENTS AND METHODS: This was a retrospective, interventional, comparative case series performed at the San Francisco Veterans Affairs Hospital. The study included 77 patients each undergoing 1 resident-performed ALT procedure from April 2006 through November 2009, and 81 patients each undergoing 1 resident-performed SLT procedure from November 2009 through December 2011. Reduction in IOP at 12 months and a longitudinal analysis across 24 months was determined. Secondary outcomes investigated included additional interventions of either repeat trabeculoplasty or trabeculectomy as well as change in eye drop medications. RESULTS: There was no evidence of a difference between IOP reductions in patients undergoing ALT compared with SLT at 12 months (P=0.41, linear modeling) or across all follow-up appointments (P=0.62, linear-mixed effects regression). Patients undergoing ALT had a significantly increased number of eye drops (+0.6 vs. -0.1 drops, P<0.001, Wilcoxon rank-sum test) and trend toward increased rates of additional interventions (P=0.06, Weibull regression). There was no difference in immediate postprocedure IOP rise between the 2 groups (P=0.75, Wilcoxon rank-sum test) or any evidence of change in visual acuity. CONCLUSIONS: We found no difference in IOP reduction between patients undergoing resident-performed ALT compared with SLT. However, patients undergoing ALT had a significant increase in eye drop medications and trend toward additional interventions compared with patients undergoing SLT.

Trabeculectomy: the limitations for registrar training.

BACKGROUND: Trainee exposure to glaucoma surgery was analysed and outcomes compared with those of consultant cases. DESIGN: Retrospective review was carried out at Princess Alexandra Hospital and Royal Brisbane and Women's Hospital, two major tertiary teaching hospitals in Brisbane, Queensland, Australia. PARTICIPANTS: Two hundred and forty-eight consecutive public patients undergoing primary trabeculectomy surgery between 2003 and 2010. METHODS: The rate of trabeculectomy performed by trainees, the success and complication rates were examined and compared with those of consultant ophthalmologists. MAIN OUTCOME MEASURES: Intraocular pressure was divided into two groups of ≤21 mmHg and ≤15 mmHg and visual field progression. RESULTS: Two hundred and forty-eight primary trabeculectomy cases were performed between 2003 and 2010. Trainees carried out 145 cases (59%), making the rate of trabeculectomy operations 1.1 per trainee per year (16-17 trainees) as compared with 1.6 per trainee per year from 1996 to 2002 at the same institutions. Complications rates in the first postoperative week were similar between consultants and trainees, the most common being wound leak and hyphaema. An intraocular pressure of ≤15 mmHg without the use of topical medications was achieved in 25 out of 50 (50%) glaucoma-interest consultant, 24 out of 53 (45.3%) general consultant and 68 out of 145 (46.9%) trainee cases (P = 0.951). The rate of visual field progression was also statistically similar between trainees and consultants (19.5% and 21.3%), respectively. CONCLUSION: With increasing trainee numbers, the rate of trabeculectomy surgery is declining compared with previous years, with less trainee exposure to trabeculectomy surgery and inability to achieve surgical competency levels.

Trabeculectomy versus ExPRESS shunt surgery in residency training.

The core curriculum for an ophthalmology residency training program should include surgical procedures relevant to a comprehensive ophthalmologist. Considerations include outcomes (success and complications), technical skill required, applicability to a wide range of disease, and cost. Using these metrics, trabeculectomy should be favored over ExPRESS shunt surgery.

Glaucoma surgery: trainee outcomes and implications for future training: southeast Scotland.

AIM: Postoperative outcome of trainee glaucoma surgery compared with glaucoma specialist consultant surgery. Survey of Scottish consultant ophthalmologists' views on trainee surgery. METHOD: Retrospective analysis of 128 trainee and 176 consultant trabeculectomies, with minimum postoperative follow-up of 2 years. Prospective postal survey of 80 Scottish consultant ophthalmologists. RESULTS: Trainees operated mainly on cases of chronic open angle glaucoma, while consultants operated on significantly more complicated glaucomas (P=0.0004). Trainee cases had more bleb leaks (P=0.01), hypotony (P=0.05), early (P=0.01) and late (P=0.03) return to theatre, and bleb interventions (P=0.01). Trainee mitomycin trabeculectomies were associated with higher rates of return to theatre (P=0.002), and cataract extraction within the first postoperative year (P=0.002). Trainee cases of pseudoexfoliation had more early complications (P=0.024), and trainee cases of low tension required more bleb interventions (P=0.05). There was no significant difference (P>0.05) between average intra-ocular pressure control (IOP) at postoperative visit year 1 between consultant (14.3 mm Hg) and trainee (13.9 mm Hg) cases. More than 50% of the 80 Scottish ophthalmology consultants surveyed, indicated that glaucoma surgery training requirements should be retained. CONCLUSIONS: Trainee trabeculectomy cases showed significantly higher rates of early complications, return to theatres, and bleb interventions compared with consultant cases. Satisfactory IOP control was achieved in both groups at postoperative year 1. Trainee cases require careful preoperative selection, avoiding complicated glaucomas including pseudoexfoliation and low tension, and those that require mitomycin. The majority of Scottish consultants wish to retain glaucoma surgery within the remit of generic training.

Trainee glaucoma surgery: experience with trabeculectomy and glaucoma drainage devices.

BACKGROUND AND OBJECTIVE: To examine outcomes of trabeculectomy with mitomycin C and glaucoma drainage device placement for uncontrolled glaucoma when performed by resident surgeons. PATIENTS AND METHODS: This study included any patient who underwent a trabeculectomy with mitomycin C (n = 93) or a glaucoma drainage device (n = 60) by a resident surgeon between 2001 and 2006. Outcome measures at 3, 6, and 12 months included failure of treatment, number of follow-up appointments, complications, number of medications, and need for further surgery. RESULTS: One year postoperatively, intraocular pressure averaged 12.1 ± 5.1 mm Hg in the trabeculectomy group and 13.0 ± 5.1 mm Hg in the glaucoma drainage device group (P = .31). Complications occurred in 30% of eyes with trabeculectomy and 10% of eyes with a glaucoma drainage device. CONCLUSION: During the first postoperative year, glaucoma drainage device surgery may have fewer complications and less morbidity than a trabeculectomy with mitomycin C when these surgeries are performed by resident surgeons. Final intraocular pressures were similar between the two groups.

A practice model for trabecular meshwork surgery.

Models for practicing ophthalmic surgery are a necessary part of all ophthalmic training. Herein, we describe a method for preparing human donor cadaveric eyes with direct visualization of the anterior chamber angle for practicing trabecular meshwork surgery. This model can be adapted for use with both fresh and formalin-fixed eyes. The use of formalin-fixed eyes decreases the risk of infection transmission inherent with human cadaveric eyes, allows prepared eyes to be stored indefinitely, and can be reused until all of the trabecular meshwork has been exhausted in surgery. We describe the application of this model for the technique of ab interno trabeculectomy using the Trabectome system for treating open-angle glaucoma.