Chiasmal and Postchiasmal Disease

Cortical Blindness Due to Neurocysticercosis in an Adolescent Patient

Neurocysticercosis (NCC) is a common cause of recent-onset seizures in both adults and children in tropical areas, especially when there is no other suggestion of another underlying neurological disorder. In addition, there have been reports of very rare cases of bilateral cortical blindness caused by this helminth in children. It is still unclear whether healthy adolescents with no pre-existing health problems could be vulnerable to developing such sequelae due to NCC. We report a case of a 14-year-old African boy from Nigeria with bilateral cortical blindness caused by NCC due to Taenia solium. According to the boy's mother, symptoms began with headaches, vomiting, fatigue, visual loss, and fever (40.0 °C). Clinical investigations led to a diagnosis of cortical blindness and encephalitis due to NCC. Appropriate treatment was administered, and it resulted in the resolution of most symptoms, though the patient remained permanently blind.

The Pupillary Light Reflex as a Biomarker of Concussion

The size of our pupils changes continuously in response to variations in ambient light levels, a process known as the pupillary light reflex (PLR). The PLR is not a simple reflex as its function is modulated by cognitive brain function and any long-term changes in brain function secondary to injury should cause a change in the parameters of the PLR. We performed a retrospective clinical review of the PLR of our patients using the BrightLamp Reflex iPhone app. The PLR variables of latency, maximum pupil diameter (MaxPD), minimum pupil diameter (MinPD), maximum constriction velocity (MCV), and the 75% recovery time (75% PRT) were associated with significant differences between subjects who had suffered a concussion and those that had not. There were also significant differences in PLR metrics over the life span and between genders and those subjects with and without symptoms. The differences in PLR metrics are modulated not only by concussion history but also by gender and whether or not the person has symptoms associated with a head injury. A concussive injury to the brain is associated with changes in the PLR that persist over the life span, representing biomarkers that might be used in clinical diagnosis, treatment, and decision making.