Prevalence and Predictors of Hering's Response in Müller's Muscle-conjunctival Resection.

PURPOSE: Determine the prevalence and predictors of Hering's response following Muller's muscle-conjunctival resection (MMCR). METHODS: Seventy-five consecutive patients undergoing unilateral MMCR were recruited in this prospective, multicenter, cohort study. Margin-reflex distance-1 (MRD1) of both eyelids was recorded preoperatively and postoperatively. One hundred forty-three variables were investigated as potential predictors of a late postoperative (≥3 months) Hering's response using regression analyses. Main outcome measures were Hering's response (≥0.5 mm descent of the unoperated eyelid from baseline), and a clinically relevant Hering's response (descent of the unoperated from baseline to a MRD1 ≤ 2.0 mm, or descent from baseline such that the MRD1 of the unoperated eyelid became >1 mm lower than the operated eyelid). RESULTS: Twenty-four (32.0%) patients had a late postoperative Hering's response, but only 6 (8.0%) responses were clinically relevant. A Hering's response at the immediate (OR 16.24, p = 0.02) and 1-week postoperative (OR 8.94, p = 0.04) timepoints predicted a late postoperative response. However, the presence (OR 7.84, p = 0.07) and amplitude (OR 8.13, p = 0.06) of a preoperative phenylephrine Hering's response did not predict a late postoperative response. Of the 10 patients with a clinically relevant phenylephrine Hering's response, only 1 demonstrated a clinically relevant response late postoperatively. CONCLUSION: Unilateral MMCR induces a clinically relevant Hering's response in 8% of patients. A preoperative phenylephrine Hering's response does not predict a late postoperative Hering's response. Therefore, when unilateral phenylephrine testing unmasks contralateral blepharoptosis, only the side with blepharoptosis at baseline should be operated.

Public perception of laser-assisted blepharoplasty versus blade-assisted blepharoplasty.

OBJECTIVE: To evaluate perceptions of blade- versus laser-based blepharoplasty before and after being provided educational information. METHODS: This interventional pre-post study included 145 randomly selected participants (Maisonneuve-Rosemont Hospital, Montreal, Canada, August 2020) who were asked about their perceptions surrounding blepharoplasty. Participants then received information about the techniques before answering final questions. RESULTS: Participants perceived no difference in outcomes for blade (37%) versus laser (40%) blepharoplasty precounselling. This increased to laser blepharoplasty postintervention (56%, p < 0.001) despite being told that there was no difference in outcomes. The higher the level of education among participants, the more likely they were to correctly believe that both techniques had similar outcomes (p = 0.049). Most participants would choose laser blepharoplasty initially (64%), and this percentage increased postintervention (81%, p < 0.001). The preintervention perception of blade blepharoplasty recovery time (20.1 ± 32.6 days) was longer than that for laser blepharoplasty (13.5 ± 32.0 days, p = 0.01) and increased for both techniques postintervention (p < 0.001). Perceived pain was lower for laser blepharoplasty. Postintervention, participants responded that additional costs of ($975 ± $1,091) would justify laser over blade blepharoplasty. CONCLUSION: Elucidating patient perceptions and preferences for blade- versus laser-based blepharoplasty provides surgeons with perspective on how to tailor preoperative counselling. Before and after the intervention, participants had a bias toward choosing laser blepharoplasty. The intervention seems to falsely convince people that laser blepharoplasty leads to better outcomes. Because the doctor's advice can greatly impact patients' decisions, physicians have to be careful not to give false expectations when counselling patients. Inaccurate recall of key educational takeaways suggests that information should be vulgarized and delivered actively to patients.

Müller Muscle Conjunctival Resection: A Multicentered Prospective Analysis of Surgical Success.

PURPOSE: This is a multicenter prospective cohort study investigating Müller muscle conjunctival resection success rates based on marginal reflex distance-1 (MRD1) and symmetry criteria. A secondary objective was to identify predictors of success. METHODS: One hundred fifty-two patients with unilateral or bilateral blepharoptosis (229 eyelids) undergoing Müller muscle conjunctival resection were consecutively recruited from 2015 to 2020 at the Université de Montréal and University of California San Francisco. Ptosis was defined as MRD1 ≤ 2.0 mm or MRD1 > 1 mm lower than the contralateral eyelid. Patients were selected for Müller muscle conjunctival resection surgery if they demonstrated significant eyelid elevation following phenylephrine 2.5% testing. MRD1 success (operated eyelid achieving MRD1 ≥ 2.5 mm) and symmetry success (patient achieving an intereyelid MRD1 difference ≤ 1 mm) were evaluated for the patient cohort. Predictors of MRD1 and symmetry success were analyzed using multivariate regression analysis. RESULTS: MRD1 success was achieved in 72.1% (n = 165) of 229 operated eyelids. Symmetry success was achieved in 75.7% (n = 115) of 152 patients. MRD1 before phenylephrine testing was the only statistically significant predictor of MRD1 success (odds ratio [OR] 2.69, p = 0.001). Symmetry following phenylephrine testing was the only variable associated with increased odds of symmetry success (OR 2.71, p = 0.024), and unilateral surgery (OR 0.21, p = 0.004), the only variable associated with reduced odds of symmetry success. CONCLUSIONS: Müller muscle conjunctival resection effectively achieves postoperative MRD1 and symmetry success. MRD1 before phenylephrine testing is the strongest determinant of MRD1 success. Neither a large rise in MRD1 with phenylephrine nor increasing tissue resection length adequately counterbalance the effect of a low MRD1 before phenylephrine. Unilateral surgery and the absence of symmetry following phenylephrine predict greater odds of symmetry failure.

Prospective evaluation of medical student accuracy conducting direct ophthalmoscopy with an unmodified iPhone X.

PURPOSE: To evaluate fundus examination accuracy of medical students when using an unmodified iPhone X or a direct ophthalmoscope in comparison to a staff ophthalmologist's retinal examination. METHODS: In this prospective comparative analysis, patients underwent dilated fundus examination by novice medical trainees using either an unmodified iPhone X or standard direct ophthalmoscope. The primary outcome was the mean difference and degree of agreement in cup-to-disc ratio between student examination and the staff ophthalmologist's cup-to-disc observation. RESULTS: A total of 18 medical students conducted 230 retinal examinations, 117 with the iPhone X and 113 with the direct ophthalmoscope. A greater proportion of students were unable to report cup-to-disc ratio using the iPhone X (81.2%) vs direct ophthalmoscope (30.1%). Student examination of cup-to-disc ratio led to a systematic bias (95% limits of agreement) of + 0.16 (-0.22 to + 0.54) and + 0.10 (-0.36 to + 0.56) with the iPhone X and direct ophthalmoscope, respectively. iPhone X and direct ophthalmoscope student observation concordance for optic disc colour (88.7 and 82.4%, respectively) and contour (68.3 and 74.2%, respectively) demonstrated low agreement with staff ophthalmologist findings. Student iPhone X observations demonstrated lower agreement with staff findings compared to direct ophthalmoscope observations for spontaneous venous pulsations (Cohen's Kappa = -0.044 vs 0.099). CONCLUSION: Amongst medical trainees, optic disc visualization using an unmodified iPhone X was inferior to the direct ophthalmoscope. When able to visualize the optic nerve head, there was no significant difference in reported cup-to-disc ratio between modalities. However, both modalities demonstrated poor reliability in comparison to staff ophthalmologist findings.

Phacomorphic Angle-closure Following Silicone Oil Tamponade in a Pediatric Patient.

PURPOSE: The purpose of this study was to report a case of phacomorphic glaucoma following retinal detachment repair with silicone oil (SO) in a pediatric patient. STUDY DESIGN: Case report. METHODS: A chart review was conducted at St. Michael's Hospital and The Hospital for Sick Children (Toronto, Canada), where the patient received ophthalmic care from July 28, 2015 onwards. RESULTS: A 14-year-old boy with a history of traumatic retinal detachment and proliferative vitreoretinopathy in the left eye, requiring 2 pars plana vitrectomies, membrane peel, and SO tamponade, presented with 1-day history of decreased vision in the left eye, severe headache, nausea, and vomiting. Visual acuity was hand motions; intraocular pressure (IOP) was 54 mm Hg; the pupil was middilated and minimally reactive with a reverse relative afferent pupillary defect. Slit-lamp examination revealed an injected eye with diffuse microcystic corneal edema, a shallow anterior chamber (AC), and an intumescent cataract. Gonioscopy demonstrated closed angles in 3 quadrants. Compared with his last examination 6 weeks prior, where only a mild posterior subcapsular cataract was noted, the patient's presentation was suggestive of rapid lens intumescence causing acute angle-closure glaucoma. He was given topical and systemic treatment, including intravenous mannitol, and his IOP reduced to 22 mm Hg after 7 hours. Urgent lensectomy was performed the following day. Preoperative ultrasound biomicroscopy revealed a greatly increased lens thickness of 5.12 mm and an AC depth of 1.12 mm. The integrity of both anterior and posterior lens capsules was confirmed intraoperatively, and SO remained confined to the posterior segment. Postoperatively, the iris returned to a normal configuration with open angles, and IOP was 16 mm Hg with no antiglaucoma medications at the last follow-up. CONCLUSIONS: Acute angle-closure in children is a rare event. To our knowledge, this is the first reported case of phacomorphic glaucoma secondary to vitreoretinal surgery in the pediatric population. Although uncommon, ophthalmologists should be aware of this potential complication with the intraocular use of SO and administer urgent treatment accordingly.

Corneal Collagen Cross-Linking in the Management of Keratoconus in Canada: A Cost-Effectiveness Analysis.

PURPOSE: To use patient-level microsimulation models to evaluate the comparative cost-effectiveness of early corneal cross-linking (CXL) and conventional management with penetrating keratoplasty (PKP) when indicated in managing keratoconus in Canada. DESIGN: Cost-utility analysis using individual-based, state-transition microsimulation models. PARTICIPANTS: Simulated cohorts of 100 000 individuals with keratoconus who entered each treatment arm at 25 years of age. Fellow eyes were modeled separately. Simulated individuals lived up to a maximum of 110 years. METHODS: We developed 2 state-transition microsimulation models to reflect the natural history of keratoconus progression and the impact of conventional management with PKP versus CXL. We collected data from the published literature to inform model parameters. We used realistic parameters that maximized the potential costs and complications of CXL, while minimizing those associated with PKP. In each treatment arm, we allowed simulated individuals to move through health states in monthly cycles from diagnosis until death. MAIN OUTCOME MEASURES: For each treatment strategy, we calculated the total cost and number of quality-adjusted life years (QALYs) gained. Costs were measured in Canadian dollars. Costs and QALYs were discounted at 5%, converting future costs and QALYs into present values. We used an incremental cost-effectiveness ratio (ICER = difference in lifetime costs/difference in lifetime health outcomes) to compare the cost-effectiveness of CXL versus conventional management with PKP. RESULTS: Lifetime costs and QALYs for CXL were estimated to be Can$5530 (Can$4512, discounted) and 50.12 QALYs (16.42 QALYs, discounted). Lifetime costs and QALYs for conventional management with PKP were Can$2675 (Can$1508, discounted) and 48.93 QALYs (16.09 QALYs, discounted). The discounted ICER comparing CXL to conventional management was Can$9090/QALY gained. Sensitivity analyses revealed that in general, parameter variations did not influence the cost-effectiveness of CXL. CONCLUSIONS: CXL is cost-effective compared with conventional management with PKP in the treatment of keratoconus. Our ICER of Can$9090/QALY falls well below the range of Can$20 000 to Can$100 000/QALY and below US$50 000/QALY, thresholds generally used to evaluate the cost-effectiveness of health interventions in Canada and the United States. This study provides strong economic evidence for the cost-effectiveness of early CXL in keratoconus.

Endovascular Management of a Traumatic Infraorbital Pseudoaneurysm Causing Orbital Compartment Syndrome.

An 89-year-old woman presented after blunt injury to the left orbit from a fall. Examination findings were suggestive of left-sided orbital compartment syndrome, unresponsive to emergent lateral canthotomy and cantholysis. CT revealed a left-sided orbital floor blowout fracture involving the infraorbital canal, with a large maxillary and infraorbital hematoma. Angiography revealed a pseudoaneurysm supplied by the infraorbital artery. Interventional neuroradiology successfully achieved hemorrhage control by endovascular obliteration of the parent artery close to the pseudoaneurysm. To our knowledge, this is the first reported case of successfully managing active intraorbital hemorrhage causing orbital compartment syndrome by endovascular vessel sacrifice of an infraorbital artery pseudoaneurysm.

The relationship between sociodemographic factors and persistence with topical glaucoma medications.

PURPOSE: To investigate the relationship between sociodemographic factors and nonpersistence with topical glaucoma medication. DESIGN: This was a retrospective, observational cohort study. PATIENTS AND METHODS: We invited glaucoma patients on medical therapy from a general ophthalmology practice to complete a standardized questionnaire between November 2011 and April 2012. Nonpersistence was defined as having ≥ 1 gaps (≥ 14 d without medication) in therapy over the last year. Patients' pharmacy records, dating back 1 year from study enrollment, were used to determine the total number of gaps and the cumulative number of days off therapy in the last year. Prevalence ratios (PR) and 95% confidence intervals (CI) were used to assess the relationship between sociodemographic factors and nonpersistence. The relationships between sociodemographic factors and the median number of gaps, as well as the median number of days off, were also assessed. RESULTS: Sixty-one patients were included for analysis. The mean age was 72 years; 61% were male patients and 71% were on one medication for glaucoma. Fifty-four percent of patients (n=33) were nonpersistent with glaucoma medications over the 1 year study period. Median numbers of gaps and days off therapy were 1 and 11, respectively. Patients reporting below average income were twice as likely to be nonpersistent (prevalence ratio, 2.02; 95% confidence interval, 1.37-2.96; P<0.01). Below average income also trended toward a greater median number of days off therapy (P=0.07). CONCLUSIONS: Below average socioeconomic status may negatively impact persistence with topical glaucoma medications, potentially threatening long-term visual outcomes.

Inter-eye differences in patients with pseudoexfoliation syndrome presenting with intraocular lens dislocation.

PURPOSE: To analyze differences in glaucoma diagnosis and glaucoma severity between fellow eyes in patients with pseudoexfoliation syndrome (PXF) who present with intraocular lens (IOL) dislocation. DESIGN: Retrospective matched case-control study. Eyes presenting with IOL dislocation (case group) were compared with fellow eyes (control group). PARTICIPANTS: Patients from a tertiary referral practice in Mississauga, Ontario, Canada. METHODS: Consecutive patients with PXF and prior bilateral uneventful cataract surgeries with in-the-bag IOLs who presented with IOL dislocation between 2008 and 2013 were identified (n=71). Indicators of glaucoma severity were compared between fellow eyes using McNemar's test and Wilcoxon signed-rank tests. Indicators of glaucoma severity were also compared pre- and post-IOL exchange/repositioning in the eye with IOL dislocation. MAIN OUTCOME MEASURES: Glaucoma diagnosis, corrected distance visual acuity (CDVA), intraocular pressure (IOP), optic nerve cup-to-disc (C/D) ratio, mean deviation (MD) on visual field, retinal nerve fiber layer (RNFL) thickness, and glaucoma medication requirements (GMRs). RESULTS: Seventy-one participants were included. The affected eye was more likely to have glaucoma (P<0.0001) and have more severe glaucoma (P=0.0001). In addition, the affected eye had worse mean CDVA (1.14±0.79 logarithm of the minimum angle of resolution [logMAR] vs. 0.35±0.46 logMAR, P<0.0005), higher mean IOP (19.2±7.2 vs. 14.7±3.6, P<0.0005), higher C/D ratio (0.54±0.22 vs. 0.51±0.20, P=0.006), greater mean number of glaucoma medication classes (1.4±1.4 vs. 0.5±1.1, P<0.0005), worse MD (-13.83±6.89 decibels [dB] vs. -6.59±6.63 dB, P<0.0005), and worse mean RNFL thickness (69.2±26.3 vs. 82.4±13.7, P=0.001). In the affected eye, there were early postoperative improvements in mean CDVA, IOP, and GMRs. CONCLUSIONS: In patients with PXF, the eye presenting with IOL dislocation was more likely than its fellow eye to have a diagnosis of glaucoma and to have glaucoma of greater severity.