John Grigg

To improve the performance of visual-evoked potentials (VEP) in the assessment of the human visual field, the multi-focal cortically scaled pattern VEP was recorded up to 250 of eccentricity in normal subjects. Monopolar and varying bipolar electrode positions were used. The monopolar response was strongly biased towards the lower hemifield. Bipolar leads straddling the inion (2 cm above and below) achieved approximately equal signals from the upper and lower visual field. Division into sectors of similar wave-form augments the analysis compared with summed full-field responses. With this technique, the multi-focal VEP can be used to objectively assess the visual field.

Developmental eye diseases, including cataract/microcornea, Peters anomaly and coloboma/microphthalmia/anophthalmia, are caused by mutations encoding many different signalling and structural proteins in the developing eye. All modes of Mendelian inheritance occur and many are sporadic cases, so provision of accurate recurrence risk information for families and affected individuals is highly challenging. Extreme genetic heterogeneity renders testing for all known disease genes clinically unavailable with traditional methods. We used whole-exome sequencing in 11 unrelated developmental eye disease patients, as it provides a strategy for assessment of multiple disease genes simultaneously. We identified five causative variants in four patients in four different disease genes, GJA8, CRYGC, PAX6 and CYP1B1. This detection rate (36%) is high for a group of patients where clinical testing is frequently not undertaken due to lack of availability and cost. The results affected clinical manag...

Microphthalmia, anophthalmia, and coloboma form an interrelated spectrum of congenital eye abnormalities. To document the ocular and systemic findings and inheritance patterns in patients with microphthalmia, anophthalmia, and coloboma disease to gain insight into the underlying developmental etiologies. This retrospective consecutive case series was conducted at a tertiary referral center. Included in the study were 141 patients with microphthalmia, anophthalmia, and coloboma disease without a recognized syndromic etiology who attended the Westmead Children's Hospital, Sydney, from 1981-2012. Cases were grouped on the basis of the presence or absence of an optic fissure closure defect (OFCD); those with OFCD were further subdivided into microphthalmic and nonmicrophthalmic cases. Anophthalmic cases were considered as a separate group. Associated ocular and systemic abnormalities and inheritance patterns were assessed. Of 141 cases, 61 (43%) were microphthalmic non-OFCD (NOFCD), 34 (24%) microphthalmic OFCD, 32 (23%) nonmicrophthalmic coloboma (OFCD), 9 (6%) anophthalmic, and 5 (4%) were unclassified. Sixty-three (45%) had bilateral disease. Eighty-four patients (60%) had an associated ocular abnormality; of these, cataract (P…

To objectively define criteria for intracranial optic nerve (ON) size in ON hypoplasia (ONH) on magnetic resonance imaging (MRI) scans. Intracranial ON sizes from MRI were compared between 46 children with ONH diagnosed by ophthalmoscopy (group 1, isolated ONH, 8 children; and group 2, ONH associated with abnormalities of the hypothalamic-pituitary axis and septum pellucidum, 38 children) and children with multiple pituitary hormone deficiency (group 3, multiple pituitary hormone deficiency, 14 children), isolated growth hormone deficiency (group 4, isolated growth hormone deficiency, 15 children), and idiopathic short stature (group 5, idiopathic short stature, 10 children). Intracranial ON size was determined by the cross-sectional area, calculated as [pi x (1/2) height x (1/2) width]. Groups 1 and 2 had lower intracranial ON size than did groups 3, 4, and 5 (P < .001). No patients in groups 3 through 5 who had MRI after 12 months of age (when 95% adult size of ONs is attained) had ONs <2.9 mm 2 . Visual acuity correlated significantly with ON size (P < .01). Magnetic resonance imaging of the ONs with cross-sectional area <2.9 mm 2 in a short child more than 12 months of age, with or without hypothalamic-pituitary axis abnormalities, confirms the clinical diagnosis of ONH.

To monitor the difference in conversion rates to multiple sclerosis (MS) in 46 patients with optic neuritis between patients with multifocal visual evoked potential latency delay and those with normal latency. Prospective case series. Metropolitan neuro-ophthalmology clinic. Forty-six patients with optic neuritis who did not have a diagnosis of MS on enrollment in the study. Conversion to MS according to the McDonald criteria. Analysis revealed that only 22 subjects had multifocal visual evoked potential latency delay. Over 1 year, 36.4% of patients with optic neuritis with latency delays progressed clinically to MS compared with 0% of those with normal latencies (P = .03, chi2). This may indicate that multifocal visual evoked potential latency delay can assist in predicting progression to future MS.