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Purpose: To evaluate whether a chromatic pupillometry test can be used to detect impaired function of intrinsically photosensitive retinal ganglion cells (ipRGCs) in patients with primary open-angle glaucoma (POAG) and to determine if pupillary responses correlate with optic nerve damage and visual loss., Design: Cross-sectional study., Participants: One hundred sixty-one healthy controls recruited from a community polyclinic (55 men; 151 ethnic Chinese) and 40 POAG patients recruited from a glaucoma clinic (22 men; 35 ethnic Chinese) 50 years of age or older., Methods: Subjects underwent monocular exposure to narrowband blue light (469 nm) or red light (631 nm) using a modified Ganzfeld dome. Each light stimulus was increased gradually over 2 minutes to activate sequentially the rods, cones, and ipRGCs that mediate the pupillary light reflex. Pupil diameter was recorded using an infrared pupillography system., Main Outcome Measures: Pupillary responses to blue light and red light were compared between control subjects and those with POAG by constructing dose-response curves across a wide range of corneal irradiances (7-14 log photons/cm(2) per second). In patients with POAG, pupillary responses were evaluated relative to standard automated perimetry testing (Humphrey Visual Field [HVF]; Carl Zeiss Meditec, Dublin, CA) and scanning laser ophthalmoscopy parameters (Heidelberg Retinal Tomography [HRT]; Heidelberg Engineering, Heidelberg, Germany)., Results: The pupillary light reflex was reduced in patients with POAG only at higher irradiance levels, corresponding to the range of activation of ipRGCs. Pupillary responses to high-irradiance blue light associated more strongly with disease severity compared with responses to red light, with a significant linear correlation observed between pupil diameter and HVF mean deviation (r = -0.44; P = 0.005) as well as HRT linear cup-to-disc ratio (r = 0.61; P < 0.001) and several other optic nerve head parameters., Conclusions: In glaucomatous eyes, reduced pupillary responses to high-irradiance blue light were associated with greater visual field loss and optic disc cupping. In POAG, a short chromatic pupillometry test that evaluates the function of ipRGCs can be used to estimate the degree of damage to retinal ganglion cells that mediate image-forming vision. This approach could prove useful in detecting glaucoma., (Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Objective: To assess the accuracy of using pupillary light reflex (PLR) in detecting glaucoma., Clinical Relevance: Glaucoma is a specific disease of the optic nerve and is often more severe in 1 eye. When large enough, this asymmetry in disease severity can cause a relative afferent pupillary defect (RAPD). Better detection of RAPDs may be one way to identify persons with glaucoma., Methods: We searched Medline and Embase through June 2012 and searched bibliographies for relevant studies for additional references. Two authors independently reviewed all articles and selected studies that assessed PLRs in patients with glaucoma. We analyzed data using mixed-effect bivariate summary receiver operating characteristic meta-analysis models., Results: A total of 30 studies were included in this review. An RAPD was observed in 9% to 82% of patients with glaucoma. Eleven studies with a total of 7271 participants were included in the analysis, and the pooled estimate corresponded to a sensitivity of 0.63 (95% confidence interval [CI], 0.43-0.80) and a specificity of 0.93 (95% CI, 0.85-0.97). After excluding 2 studies that used the swinging flashlight test, the sensitivity increased to 0.74 (95% CI, 0.59-0.85) with a specificity of 0.85 (95% CI, 0.77-0.90). Study designs and different pupil measurement techniques explained part of the heterogeneity between studies., Conclusions: Patients with glaucoma frequently have an abnormal PLR and comparing the responses between the 2 eyes can in part distinguish between those with glaucoma and those without the disease. Newer instruments and analytic approaches to assess pupil function may improve the performance of pupil screening., (Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To describe the clinical characteristics of and risk factors for the development of optic neuropathy after pars plana vitrectomy (PPV) for macula-sparing primary rhegmatogenous retinal detachment (RRD) repair., Design: Retrospective case-control study., Participants: Seven patients who underwent PPV for macula-sparing primary RRD with subsequent development of optic neuropathy and 42 age- and gender-matched control patients undergoing PPV for macula-sparing primary RRD., Methods: Retrospective chart review of medical and surgical records., Main Outcome Measures: Clinical features of patients who developed optic neuropathy after PPV for macula-sparing RRD and analysis of potential risk factors (age, gender, medical history, surgical technique, intraoperative ocular perfusion pressure [OPP], and operative time)., Results: At last follow-up, all 7 patients with optic neuropathy had visual acuity less than 20/200, relative afferent pupillary defects, optic nerve pallor, and visual field defects. A total of 5 of 7 patients (71%) demonstrated intraoperative reduced OPP with associated systemic hypotension compared with 7 of 42 patients (17%) in the control cohort (P = 0.01)., Conclusions: Optic neuropathy after PPV for macula-sparing primary RRD is a rare but potentially devastating complication. Although the cause is often unclear, reduced ocular perfusion due to intraoperative systemic hypotension may be a contributing risk factor in some eyes., (Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Objective: To identify clinical and pupillographic features of patients with a relative afferent pupillary defect (RAPD) without visual acuity or visual field loss caused by a lesion in the dorsal midbrain., Design: Experimental study., Participants and Controls: Four patients with a dorsal midbrain lesion who had normal visual fields and a clinically detectable RAPD., Methods: The pupil response from full-field and hemifield light stimulation over a range of light intensities was measured by computerized binocular pupillography., Main Outcome Measures: The mean of the direct and consensual pupil response to full-field and hemifield light stimulation was plotted as a function of stimulus light intensity., Results: All 4 subjects showed decreased pupillographic responses at all intensities to full-field light stimulation in the eye with the clinical RAPD. The pupillographic responses to hemifield stimulation showed a homonymous pattern of deficit on the side ipsilateral to the RAPD, similar to that observed in a previously reported patient with an optic tract lesion., Conclusions: The basis of a midbrain RAPD is the nasal-temporal asymmetry of pupillomotor input that becomes manifest when a unilateral postchiasmal lesion interrupts homonymously paired fibers traveling in the contralateral optic tract or midbrain pathway to the pupillomotor center, respectively. The pupillographic characteristics of an RAPD resulting from a dorsal midbrain lesion thus resemble those of an RAPD resulting from a unilateral optic tract lesion, but without the homonymous visual field defect., Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article., (Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Objective: To estimate the magnitude and causes of visual impairment (VI) in people aged > or = 50 years in Kunming using the Rapid Assessment for Avoidable Blindness methodology, and to assess the prevalence of a pupillary defect in participants diagnosed as cataract visually impaired., Design: Population-based cross-sectional survey., Participants: We enrolled 2760 residents of Kunming prefecture in southwest China, >50 years of age., Methods: Forty-six clusters of 60 people were selected based on population proportional to size. Households from each cluster were selected using compact segment sampling (CSS) or quota sampling when CSS was not feasible. Visual acuity (VA) was assessed using a tumbling E chart. Lens status and cause of VI were determined by ophthalmologists using direct ophthalmoscopy through a dilated pupil where necessary. The pupillary reaction was assessed on undilated pupils when VI was detected., Main Outcome Measures: Prevalence of blindness (VA<3/60), severe VI (SVI) (VA<6/60), and VI (VA<6/18) using presenting VA (PVA). The causes of blindness and VI and prevalence of a pupillary defect in the cataract visually impaired were also assessed., Results: Of 2760 enumerated residents, 2588 were examined. The sample prevalence of bilateral blindness was 3.7% (95% confidence interval [CI], 2.8-4.6%). The prevalence of SVI was 3.0% (95% CI, 2.2-3.8%), and of VI was 9.1% (95% CI, 7.5-10.7%). The main cause of blindness was cataract (63.2% of blindness), followed by nontrachomatous corneal scar (14.7%), glaucoma (7.4%), and other posterior segment disease/neurologic disorders (4.2%). A pupillary defect was detected in 16% of those diagnosed with cataract VI. The cataract surgical coverage in the bilaterally blind was 58.9%, and 45% of operated eyes had good outcome with available correction (VA>6/18). The main barrier to cataract surgery was cost., Conclusions: Cataract remains the most important cause of preventable blindness in this poor region of China, and affordable provision of surgery would help to address this problem. Some cases of cataract blindness may not be preventable owing to preexisting comorbidity, as detected by the presence of a pupillary defect.

Objective: To report a case of bilateral optic neuropathy after bilateral laser-assisted in situ keratomileusis (LASIK) surgery., Design: Observational case report., Methods: Complete eye examination with detailed evaluation of the optic nerve, detailed medical history, stereo disc photographs, GDx Nerve Fiber Analyzer testing, Humphrey 24-2 SITA visual field testing, diurnal intraocular pressure measurement, serologic evaluation, and magnetic resonance imaging of the brain and orbits., Main Outcome Measures: Optic nerve status, visual field status, and visual acuity., Results: A subject with previously healthy optic nerves had bilateral optic neuropathy develop after LASIK surgery. This neuropathy manifested with a subjective decrease in visual field, normal visual acuity, normal color vision, relative afferent pupillary defect, increased cupping of the optic nerve with focal neuroretinal rim defects, decreased nerve fiber layer thickness, and nerve fiber bundle-type visual field defects. The subject had no other risk factors for optic neuropathy. No other cause of neuropathy was identified., Conclusions: Optic neuropathy is a potential vision-threatening complication of LASIK surgery. This complication may be due to barotrauma or ischemia related to extreme elevation of intraocular pressure by the suction ring. Careful examination of the optic nerve before and after LASIK surgery is warranted.

Objective: To investigate the ability of a portable, personal computer-driven, pupillometer to record the pupillary response curve during the swinging flashlight test. Also, to determine whether these response curves can be used to identify and quantify relative asymmetry in the pupillary light reflex between eyes in healthy volunteers with simulated afferent pupil defects (APDs) and patients with optic neuropathies., Design: Comparative, observational case series and instrument validation., Participants: Healthy volunteers with no known ocular disease and patients (n = 20) with various optic neuropathies noted to have relative APDs on examination., Methods: Pupillary response curves of the right eye were recorded with a portable, electronic, infrared pupillometer from healthy volunteers (with and without simulated APDs) and patients with APDs while the light stimulus alternated between eyes, simulating the swinging flashlight test. Simulated APDs in healthy volunteers were created with increasingly dense neutral density filters in front of the left eye., Main Outcome Measures: Differences in constriction amplitude, latency, and constriction velocity of the pupillary response with right eye stimulation versus left eye stimulation in both groups of subjects., Results: A significant correlation between neutral density filter strength and intereye differences was seen for all measurement parameters in volunteers with simulated APDs. Depending on the measurement parameter and stimulus intensity, simulated APDs of 0.6 log units or more could be distinguished from normal responses. Clinically graded true APDs had intereye differences similar to simulated APDs of the same density. Those with real and simulated APDs of 0.9 log units or more could be distinguished from healthy volunteers with 80% sensitivity and 92% specificity. Responses from those with real and simulated small APDs of 0.3 to 0.6 log units could not be distinguished reliably., Conclusions: Portable, personal-computer driven, electronic, infrared pupillography can record the swinging flashlight test accurately and identify large afferent pupillary defects. An affordable, portable, reliable device for identifying relative APDs would be useful in the identification and follow-up of patients with neurogenic vision loss.

Objective: The authors compared two methods, the Marcus Gunn test and the alternating light test, for detecting a relative afferent pupillary defect., Design: A randomized, prospective clinical trial., Participants: Fourteen patients with unilateral optic neuropathy., Intervention: The Marcus Gunn and alternating light tests were performed on each patient., Main Outcome Measures: The results of the Marcus Gunn and altemating light tests for detecting a relative afferent pupillary defect on the affected side., Results: The Marcus Gunn test was able to identify the affected eye in only 8 of 14 patients, whereas the alternating light test correctly identified the affected eye in 13 of 14 patients. Results of the Marcus Gunn test were indeterminate in 4 of 14 patients and were incorrect in 2 of 14 patients. Results of the alternating light test were indeterminate in one patient and never incorrectly identified the affected eye., Conclusion: The alternating light test is superior to the Marcus Gunn test for detecting relative afferent pupillary defects.