Jonathan C Park

Effect of distraction on simulated anterior segment surgical performance

PURPOSE: To determine the effect of distraction on anterior segment surgical performance using a virtual reality simulator in expert and novice surgeons. SETTING: Horizon Suite Simulation Centre, South Devon Foundation NHS Trust, Devon, England. DESIGN: Cohort study. METHODS: Expert and novice ophthalmic surgeons completed a standardized and validated surgical task 10 times on a virtual reality simulator (EyeSi). They then completed a cognitive task (arithmetic questions), after which they completed 10 attempts on the simulator module while also completing the cognitive task. RESULTS: For experts (n = 7), the distracting cognitive task had no statistically significant effect on operating scores. The rate of correctly answered questions decreased from 12.3 per minute ± 2.1 (SD) while single tasking to 8.6 ± 3.1 per minute while dual tasking (P=.018). For novices (n = 14), the distracting cognitive task had no effect on any operating score except a small reduction in the penalty odometer score. The rate of correctly answered questions decreased from 11.5 ± 4.1 per minute while single tasking to 7.0 ± 3.2 per minute while dual tasking (P=.001). CONCLUSION: A distractive cognitive task reduced the ability of novice surgeons and expert surgeons to deal with that cognitive task, although their simulated surgical performance was not overtly compromised. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Safety of nondominant-hand ophthalmic surgery

PURPOSE: To establish the safety of nondominant‐hand simulated intraocular surgery. SETTING: Horizon Suite Simulation Centre, South Devon Foundation NHS Trust, Devon, United Kingdom. DESIGN: Cohort study. METHODS: Physicians with no previous ophthalmic surgical experience completed an introductory program on the EyeSi ophthalmic surgical simulator to eliminate the learning curve. They then completed the validated level‐4 forceps module 4 times with their dominant hand and then 4 times with their nondominant hand. Simulator total score, odometer movement, corneal injury, lens injury, and total time were recorded. Acuity (Snellen near) and stereoacuity (Frisby) were also recorded. RESULTS: All 30 physicians showed good acuity (6/6 and N6 or better) and stereopsis (mean 35 seconds of arc). The total score was lower (mean 60.8 versus 65.6; P=.019), operating times were longer (mean 71.6 versus 70.0; P=.026), and lens injury was greater (mean 0.93 versus 0.79, P=.021) when operating with the nondominant hand than with operating with the dominant hand. Those with higher scores with the dominant hand had higher scores with their nondominant hand. CONCLUSIONS: Simulated nondominant‐hand ophthalmic surgery resulted in less efficient, less safe, and slower surgery. This observation was more marked in those with less skill with their dominant hand. This has practical implications for trainee and trainer if 1 surgeon is left handed and 1 right handed. It also suggests that a higher degree of competence with the dominant hand is required before performing nondominant‐hand surgery. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned.

Can virtual reality simulation help to determine the importance of stereopsis in intraocular surgery

Aim To establish the effect of acute loss of stereopsis on simulated intraocular surgical performance. Methods This study was performed using the EYESi ophthalmic surgical simulator. Thirty junior doctors with no previous ophthalmic surgical experience were enrolled and distance visual acuity (Snellen), near visual acuity and stereoacuity (Frisby) were recorded. All participants completed a standard introductory programme on the forceps module to eliminate the learning curve. They then undertook four attempts of level 4 forceps module binocularly and another four monocularly to simulate an acute loss of stereopsis. Total score, odometer movement, corneal area injured, lens area injured and total time taken were recorded. Results Mean age was 31 years (SD±9). None had amblyopia, with all demonstrating distance visual acuity of 6/6 or better and N6 for near. Mean stereopsis was 35 s of arc (SD±18). Average total score decreased from 60 while operating binocularly to 47 monocularly (p<0.05). Average corneal area injured increased from 0.95 mm2 to 2.30 mm2 (p<0.05), average lens area injured increased from 1.76 mm2 to 3.53 mm2 (p<0.05) and average time taken increased from 69.6 s to 77.4 s (p<0.05). Conclusion The importance of stereopsis for intraocular surgery is difficult to establish in a live theatre setting without compromising patient safety. Virtual reality simulators provide a safe alternative. This study demonstrates a statistically significant decrease in simulated intraocular surgical performance with acute loss of stereopsis in potential ophthalmic training applicants. Caution is recommend in using these results to advocate stereopsis testing as a screening tool in interviews because some participants performed well despite an absence of stereopsis.

Intraocular lens opacification after corneal endothelial keratoplasty: Electron microscopy and x-ray element spectroscopy analysis

Purpose To assess a newly recognized long‐term complication of Descemet‐stripping automated endothelial keratoplasty (DSAEK). Setting Plymouth Royal Eye Infirmary and Plymouth Electron Microscope Centre, Plymouth, United Kingdom. Design Retrospective case series. Methods This study evaluated cases of intraocular lens (IOL) opacification that developed after uneventful DSAEK. None of the IOLs was previously known to opacify. In 1 case, the opacified IOL was explanted and analyzed using detailed light microscopy, scanning electron microscopic (SEM) analysis, and element x‐ray spectroscopy. Results In all 5 cases, the IOL was hydrophilic acrylic and the eye developed IOL anterior surface opacification 4 to 12 months after DSAEK. In 1 eye, the opacification was symptomatic; thus, an IOL exchange was performed. Light microscopy and SEM analysis of the explanted IOL confirmed opacification on the anterior surface and subsurface areas. X‐ray element spectroscopy showed the granules were composed of calcium and phosphorous. Conclusions These cases indicate that IOL opacification after DSAEK is a late, although newly recognized, complication of endothelial keratoplasty. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Tectonic lamellar keratoplasty: simplified management of corneal perforations with an automated microkeratome.

OBJECTIVE To describe a simplified tectonic lamellar keratoplasty (LK) technique, which can be used to manage full-thickness corneal perforations. DESIGN Case series demonstrating a new surgical technique. PARTICIPANTS A 69-year-old female with rosacea keratitis and peripheral corneal perforation; a 49-year-old male with keratoconus, ipsilateral herpes simplex keratitis and an inferonasal corneal perforation; and a 12-year-old female with an apparently spontaneous central corneal perforation. RESULTS These 3 patients with full-thickness corneal perforations were successfully managed with this automated tectonic LK technique. CONCLUSIONS Tectonic LK has benefits relative to tectonic penetrating keratoplasty but remains unpopular because it is technically difficult to prepare the host and donor corneas. This tectonic LK technique negates the need for challenging free-hand dissection and gives an excellent donor fit to the host bed. This provides an easier and more effective way to manage corneal perforations.

Improving the operative rate for cataract surgery.

Purpose To establish a cataract referral patient pathway that is of high quality and of greater efficiency and to compare the operative rates (conversion to surgery from referral) for patients referred via the new refined direct optometrist (RDO) pathway and for those referred by general practitioners (GPs). Setting Bristol Eye Hospital, Bristol, United Kingdom. Design Cohort study. Methods A retrospective cohort of patients referred to the “1‐stop cataract clinic” at Bristol Hospital Eye Service between November 1, 2008, and May 31, 2010, were identified. The operative rates between the 2 pathways were compared. Results Of the patients, 4657 were referred; 4222 were referred via the traditional GP route and 435 via the RDO route. Operative rates (conversion to surgery from referral) were higher for the RDO pathway than for the GP pathway (91.9% versus 82.4%) (P=.0043). Conclusions By combining referral information from optometrists and GPs, a high‐quality and efficient cataract surgery patient pathway can be established. This has major economic advantages, and this scheme could be adopted at a national level. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.