ABSTRACT
Nitrous oxide is used as an anaesthetic and analgesic agent in the medical setting and is known to cause raised intracranial pressure. The use of nitrous oxide recreationally for the drug's euphoric and relaxant properties has been linked to multiple neurological and psychiatric sequelae including neuropathy, myelopathy, and psychosis. We describe a case of a young person who declared heavy nitrous oxide use resulting in vision-threatening papilloedema secondary to raised intracranial pressure. He underwent emergency lumbar drainage alongside high-dose acetazolamide and parenteral vitamin B12 injections. To our knowledge, there have yet to be other reports of cases where heavy nitrous oxide use has caused secondary pseudotumor cerebri syndrome.
ABSTRACT
TOPIC: This systematic review examined geographical and temporal trends in medical school ophthalmology education in relationship to course and student outcomes. CLINICAL RELEVANCE: Evidence suggesting a decline in ophthalmology teaching in medical schools is increasing, raising concern for the adequacy of eye knowledge across the rest of the medical profession. METHODS: Systematic review of Embase and SCOPUS, with inclusion of studies containing data on medical school ophthalmic course length; 1 or more outcome measures on student ophthalmology knowledge, skills, self-evaluation of knowledge or skills, or student course appraisal; or both. The systematic review was registered prospectively on the International Prospective Register of Systematic Reviews (identifier, CRD42022323865). Results were aggregated with outcome subgroup analysis and description in relationship to geographical and temporal trends. Descriptive statistics, including nonparametric correlations, were used to analyze data and trends. RESULTS: Systematic review yielded 4596 publication titles, of which 52 were included in the analysis, with data from 19 countries. Average course length ranged from 12.5 to 208.7 hours, with significant continental disparity among mean course lengths. Africa reported the longest average course length at 103.3 hours, and North America reported the shortest at 36.4 hours. On average, course lengths have been declining over the last 2 decades, from an average overall course length of 92.9 hours in the 2000s to 52.9 hours in the 2020s. Mean student self-evaluation of skills was 51.3%, and mean student self-evaluation of knowledge was 55.4%. Objective mean assessment mark of skills was 57.5% and that of knowledge was 71.7%, compared with an average pass mark of 66.7%. On average, 26.4% of students felt confident in their ophthalmology knowledge and 34.5% felt confident in their skills. DISCUSSION: Most evidence describes declining length of courses devoted to ophthalmology in the last 20 years, significant student dissatisfaction with courses and content, and suboptimal knowledge and confidence. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.