PurposeVariation of retinal light sensitivity between winter and summer seasons may be a marker for seasonal affective disorder and the basis for response to phototherapy. As the pupil is a marker of retinal light sensitivity and shows a 24‐hour variation that reflects circadian rhythm, we used the pupil as proxy to assess light sensitivity of rods, cones and melanopsin as a function of seasonal light in healthy adults.Methods37 adults were tested during the short (January‐February) and long (July‐August) annual photoperiods. All subjects completed standardized questionnaires of seasonality and sleep. Pupil responses to blue (470 nm) and red (622 nm) light were recorded under dark and light adapted conditions using an automated pupillometer. Main outcome parameters were maximal contraction amplitude and post‐stimulus contraction amplitude.ResultsAll but two subjects reported good sleep quality. One subject was an extreme morning type. Twelve subjects reported a global seasonal variation in sleep, mood and appetite but without dysfunction or disability. Baseline pupil size of light adapted eyes was greater in summer compared to winter. Maximal contraction amplitudes to scotopic and photopic light stimuli were greater in summer. The post‐stimulus pupil contraction was also greater in summer, but only after light adaptation.ConclusionsBaseline pupil size and pupil responses derived from rods, cones and melanopsin photoreception were greater in summer in healthy adults. This seemingly greater retinal sensitivity to light when the photoperiod (daylength) is long suggests a more central basis for seasonal regulation of the pupil light reflex.
Background and objectives: We aimed to evaluate the effects of the water drinking test (WDT) on several systemic and ocular parameters, including choroidal thickness, which was assessed through optical coherence tomography angiography (OCTA), in glaucoma suspects. Materials and Methods: A total of 40 eyes from 20 glaucoma suspects without any systemic or ocular diseases were included in this prospective observational study. All the participants undertook the WDT, which required the drinking of 1 L of table water in 5 min. The outcome measures included IOP, systolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), mean ocular perfusion pressure (MOPP), ocular pulse amplitude (OPA), and subfoveal and peripapillary choroidal thickness, which were assessed at baseline and at four 15 min intervals after the WDT. Generalized least squares models and mixed model analyses that take into account repeated measurements were used to assess the changes over time of these parameters. Results: All the ocular and systemic parameters showed statistically significant changes at all time points compared to baseline apart from choroidal thickness. The peak changes were an IOP of 20.1 mmHg versus 17.3 mmHg at 45 min, an SBP of 137.6 mmHg versus 125 mmHg at 30 min, a DBP of 95.9 mmHg versus 85.7 mmHg at 15 min, and an MOP of 53.51 mmHg versus 48.89 mmHg at 15 min. Conclusions: Despite elevations in IOP and significant changes in all the assessed systemic parameters, the WDT was not associated with changes in choroidal thickness in glaucoma suspects.
To describe the off-label use of lyophilized equine pericardium for tectonic enhancement of the sclera in a case of progressive scleromalacia perforans.Methods: An 82-year-old woman with a history of varicella zoster virus sclerokeratitis presented with a progressively expanding scleral thinning at the superonasal quadrant of the anterior sclera of her left eye. The eye was blind because of intractable glaucoma. To avoid perforation of the exposed choroid, a single layer of lyophilized equine pericardium was sutured over the scleral perforation. After performing a conjunctival peritomy in the involved superonasal area, the pericardium was trimmed, fixated on the anterior sclera with 4 Nylon 9 to 0 interrupted sutures, and tucked underneath the conjunctival pocket. The conjunctiva was adapted with 6 Vicryl 8 to 0 interrupted sutures. Results:The postoperative course was uneventful. At 12 months after surgery, slit-lamp biomicroscopy showed a stable subconjunctival sheet covering the staphyloma, whereas anterior segment optical coherence tomography demonstrated thickening of the ocular wall, suggesting successful integration of the pericardium.Conclusions: Suturing of equine pericardium over a scleral defect was feasible allowing successful reinforcement of the staphyloma in a case of severe scleromalacia perforans.
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