Optic neuropathy from hypovitaminosis A in a series of children with severe dietary restrictions.

AIM: Hypovitaminosis A is a leading cause of preventable childhood blindness, especially in developing nations. Vitamin A is a fat-soluble essential micronutrient that serves vital functions in the visual system and in regulating bone resorption. We report on a series of four children with mixed nutritional and compressive optic neuropathy and provide a review of the literature. METHODS: A retrospective observational study of four males (ages 9-12), three with autism spectrum disorder who presented with loss of vision and multiple vitamin deficiencies including hypovitaminosis A. RESULTS: Patients presented with unexplained visual loss or a change in visual behaviour. All patients had severely restricted diet comprising of predominantly carbohydrates. Two of the four cases demonstrated optic nerve pallor at initial presentation with marked optic atrophy developing in all patients over time. Electrophysiology available in two patients demonstrated optic nerve dysfunction with preserved retinal function. Extensive investigations revealed profound deficiency in multiple vitamins including vitamin A (<0.1-0.2 µmol/L, normal = 0.9-1.7 µmol/L). Three patients also had low vitamin B12 (90-111 pmol/L, normal = 170-800 pmol/L) with normal folate. All four cases had radiological evidence of skull base thickening indicative of low vitamin A. Genetic testing did not find any relevant pathogenic variants. CONCLUSIONS: Hypovitaminosis A is a crucial form of nutritional deprivation that results in significant visual loss with potential hyperostosis and optic nerve compression exacerbating nutritional optic neuropathy. Additional micronutrient deficiencies usually co-exist and may contribute. Extra vigilance in vitamin replacement is required of clinicians with patients with autism who have restricted diets.

Case report: tuberous sclerosis and persistent hyperplastic primary vitreous.

BACKGROUND: Persistent hyperplastic primary vitreous (PHPV) in a patient with tuberous sclerosis (TS) has been described in one previous case report in 1999. Otherwise, there is no literature around this potential association. We describe a case of an infant with TS and PHPV. CASE PRESENTATION: An 11-month old male was under investigation for leukocoria, microphthalmia and suspected PHPV after being seen in ophthalmology clinic. He presented to hospital with seizures and was diagnosed with TS on imaging. Imaging also showed the known microphthalmia and a mass associated with the lens. Subsequent paediatric ophthalmology review and examination under anaesthesia confirmed microphthalmia, PHPV and a retrolental mass which was thought to represent total retinal detachment or a retinal hamartoma within a retinal detachment. CONCLUSIONS: This is the second case report of PHPV in a patient with TS. The previous case report postulated that the atypical location of the retinal hamartoma was secondary to the abnormal globe development in PHPV.

Duration of conjunctival redness following adult strabismus surgery.

PURPOSE: To determine the duration of postoperative conjunctival injection following strabismus surgery and to assess how this is affected by previous extraocular muscle surgery. This would improve preoperative counseling of strabismus patients. METHODS: Subjective evaluation of conjunctival redness based on patient questionnaire response. RESULTS: Fifty-three patients returned completed questionnaires. A total of 93 muscles were operated on. Of these, 46 had not undergone previous operations; 47 had. Previously unoperated eyes remained red for a median duration of 9.5 weeks; reoperated eyes remained red for a median of 11 weeks. Of the 93 muscles, 50 were sutured with adjustable sutures. These remained red for a median duration of 11 weeks. Muscles tied with nonadjustable sutures remained red for a median of 10 weeks. CONCLUSIONS: In both previously unoperated and reoperated eyes, conjunctival redness resolved in approximately 10 weeks; adjustable sutures did not alter the duration of redness significantly.