Comprehensive characterization of a Canadian cohort of von Hippel-Lindau disease patients.

Von Hippel-Lindau disease (VHL) is a heritable condition caused by pathogenic variants in VHL and is characterized by benign and malignant lesions in the central nervous system (CNS) and abdominal viscera. Due to its variable expressivity, existing efforts to collate VHL patient data do not adequately capture all VHL manifestations. We developed a comprehensive and standardized VHL database in the web-based application, REDCap, that thoroughly captures all VHL manifestation data. As an initial trial, information from 86 VHL patients from the University Health Network/Hospital for Sick Children was populated into the database. Analysis of this cohort showed missense variants occurring with the greatest frequency, with all variants localizing to the α- or ß-domains of VHL. The most prevalent manifestations were central nervous system (CNS), renal, and retinal neoplasms, which were associated with frameshift variants and large deletions. We observed greater age-related penetrance for CNS hemangioblastomas with truncating variants compared to missense, while the reverse was true for pheochromocytomas. We demonstrate the utility of a comprehensive VHL database, which supports the standardized collection of clinical and genetic data specific to this patient population. Importantly, we expect that its web-based design will facilitate broader international collaboration and lead to a better understanding of VHL.

A comparison of hand- and foot-activated surgical tools in simulated ophthalmic surgery.

OBJECTIVE: To compare the performance characteristics of hand-activated surgical tools with those of foot-activated surgical tools using a virtual-reality simulator of intraocular surgery. DESIGN: Prospective, unmasked, interventional cohort study. PARTICIPANTS: Eighteen ophthalmology residents at the University of Toronto. METHODS: The EYESi ophthalmic surgery simulator was used for the study. The surgical tool evaluated was a simulation of intraocular forceps activated by either a handpiece or a foot pedal. Each resident completed 2 modules-a dexterity module and a capsulorrhexis/cataract module. Each module was completed 4 times, alternating between the hand-activated forceps and the foot-activated forceps. An overall score was calculated for each task on the basis of the efficiency and accuracy of completion of the task, with 100 representing a perfect score. Overall scores were compared between hand and foot control for both modules. RESULTS: For the dexterity module, there was no significant difference in the overall scores between the 2 groups (91 ± 6 and 93 ± 6 for the foot- and hand-activated forceps groups, respectively; p > 0.05, t test). For the capsulorrhexis module, overall scores were also similar for both groups, the scores being 50 ± 21 and 53 ± 16 for the foot- and hand-activated forceps groups, respectively (p > 0.05, t test). An exit survey of the study's participants revealed that subjects did not have a preference for the hand or foot modality of the forceps tool, with 10 preferring the hand-activated forceps tool and 8 preferring the foot-activated tool. CONCLUSIONS: During simulated intraocular surgery, foot- and hand-activated surgical tools appear to have similar performance characteristics and are equally well received by residents.

Psychometric properties of a new tool to assess task-specific and global competency in cataract surgery.

BACKGROUND AND OBJECTIVE: To establish and validate an assessment tool of cataract surgery performed by residents suitable for a competency-based curriculum. PATIENTS AND METHODS: A three-component evaluation tool was created based on review of the literature and was refined using a modified Delphi technique. Faculty surgeons viewed two videos of cataract surgery, performed by a novice and an expert, and completed the evaluation tool. Results were analyzed for the psychometric properties. RESULTS: Evaluators concluded the scale had excellent face validity. Construct validity showed the scale to reliably distinguish (P < .001) between novice (30.3 ± 6.1) and experienced (48.3 ± 7.2) surgeons. Internal consistency of the scale was high, with Cronbach's alpha equal to 0.981. Inter-rater reliability was high with an intraclass correlation coefficient equal to 0.811 (F(df) = 53.2 (25), P < .001). CONCLUSION: The tool has excellent face validity, content validity, and reliability. Its task-specific, global-index scale and quantitative data form make it a valuable tool to assess residents' surgical skills.

Primary piggyback implantation of 3 intraocular lenses in nanophthalmos.

We present a patient with bilateral nanophthalmos who had uneventful cataract extraction in the right eye with primary implantation of 3 intraocular lenses (IOLs) of 2 different materials: a 30 diopter (D) acrylic IOL and a 9 D silicone IOL in the capsular bag and a 30 D silicone IOL in the ciliary sulcus. Subsequently, cataract extraction was done in the left eye with bag-sulcus implantation of two 30 D silicone IOLs. The use of 3 IOLs in 1 eye was necessary because the highest available power of acrylic and silicone IOLs at our institution was 30 D. The only short-term complications were temporary corneal edema and partial displacement of the sulcus IOL anterior to the iris in the right eye and bilateral posterior capsule opacification. The late complication of interlenticular opacification was not present 1 year after piggyback IOL implantation.

Outcomes of repeat penetrating keratoplasty and risk factors for graft failure.

PURPOSE: To compare repeat penetrating keratoplasty (PKP) with primary PKP with respect to patient characteristics, survival rates, and risk factors for graft failure. METHODS: Retrospective, consecutive, noncomparative case series of 116 patients who underwent repeat PKP and who were identified from a cohort of 696 PKPs performed by one surgeon over a 7.5-year period. RESULTS: Compared with patients who underwent primary PKP, regraft patients were 5 years older, had a higher rate of peripheral anterior synechiae (PAS), were more likely to require intraocular pressure (IOP)-lowering medications prior to surgery, were more likely to develop postoperative corneal neovascularization, were less likely to be phakic, and were more likely to undergo PKP in conjunction with a lens procedure. There was no difference between the two groups with respect to the distribution of original diagnoses leading to PKP and the rate of graft rejection. Two- and 5-year survival rates for repeat PKP were 63.9% and 45.6%, respectively. In a multivariate analysis, the original diagnosis leading to corneal transplantation, the presence of preoperative PAS, intraoperative anterior vitrectomy, and postoperative corneal neovascularization were identified as risk factors for graft failure in patients undergoing a regraft. CONCLUSIONS: Patients undergoing PKP for the first and second time share common risk factors for graft failure, namely, the original diagnosis leading to corneal transplantation, the presence of preoperative PAS, and the occurrence of postoperative corneal neovascularization. The difference in graft survival rates between the two groups can be partially explained on the basis of higher rates of the latter two risk factors among regrafts.