Musarat Awan

Mutations in FRMD7, a newly identified member of the FERM family, cause X-linked idiopathic congenital nystagmus

Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability.

Mutations in FRMD7, a newly identified member of the FERM family, cause X-linked idiopathic congenital nystagmus.

Idiopathic congenital nystagmus is characterized by involuntary, periodic, predominantly horizontal oscillations of both eyes. We identified 22 mutations in FRMD7 in 26 families with X-linked idiopathic congenital nystagmus. Screening of 42 singleton cases of idiopathic congenital nystagmus (28 male, 14 females) yielded three mutations (7%). We found restricted expression of FRMD7 in human embryonic brain and developing neural retina, suggesting a specific role in the control of eye movement and gaze stability.

Why is compliance with occlusion therapy for amblyopia so hard? A qualitative study

Objective: To explore parents’ perceptions and experiences of occlusion (patching) therapy for treatment of amblyopia in children. Methods: Qualitative study involving semistructured interviews with 25 families of a child with amblyopia being treated at a specialist clinic. Interviews were tape recorded and transcribed verbatim. Data analysis was based on the constant comparative method, assisted by qualitative analysis software. Results: Parents of children prescribed patching treatment found themselves obliged to manage the treatment. This involved dilemmas and tensions, with many parents describing children’s distress, particularly in the early stages of patching treatment. Parents were highly sensitive to the credibility of the treatment, but were sometimes confused by information given in the clinic or did not see clinic staff as authoritative. There was evidence that parents were likely to abandon or modify treatment if no improvement could be detected or if the child continued to suffer socially or educationally. Parents described a range of strategies for facilitating patching, including explanation; normalisation; rewards; customising the patch; establishing a routine; and enlisting the help of others. Whatever their practices in relation to patching, parents were keen to defend their behaviour as that of a “good parent”. Conclusions: Interventions that aim to improve compliance should take account of the difficulties and tensions experienced by parents, rather than simply treating non-compliance as resulting from information deficits. Practical support that builds on strategies described by parents is likely to be of benefit.

Phenotypical characteristics of idiopathic infantile nystagmus with and without mutations in FRMD7

Idiopathic infantile nystagmus (IIN) consists of involuntary oscillations of the eyes. The familial form is most commonly X-linked. We recently found mutations in a novel gene FRMD7 (Xq26.2), which provided an opportunity to investigate a genetically defined and homogeneous group of patients with nystagmus. We compared clinical features and eye movement recordings of 90 subjects with mutation in the gene (FRMD7 group) to 48 subjects without mutations but with clinical IIN (non-FRMD7 group). Fifty-eight female obligate carriers of the mutation were also investigated. The median visual acuity (VA) was 0.2 logMAR (Snellen equivalent 6/9) in both groups and most patients had good stereopsis. The prevalence of strabismus was also similar (FRMD7: 7.8%, non-FRMD7: 10%). The presence of anomalous head posture (AHP) was significantly higher in the non-FRMD7 group (P < 0.0001). The amplitude of nystagmus was more strongly dependent on the direction of gaze in the FRMD7 group being lower at primary position (P < 0.0001), compared to non-FRMD7 group (P = 0.83). Pendular nystagmus waveforms were also more frequent in the FRMD7 group (P = 0.003). Fifty-three percent of the obligate female carriers of an FRMD7 mutation were clinically affected. The VAs in affected females were slightly better compared to affected males (P = 0.014). Subnormal optokinetic responses were found in a subgroup of obligate unaffected carriers, which may be interpreted as a sub-clinical manifestation. FRMD7 is a major cause of X-linked IIN. Most clinical and eye movement characteristics were similar in the FRMD7 group and non-FRMD7 group with most patients having good VA and stereopsis and low incidence of strabismus. Fewer patients in the FRMD7 group had AHPs, their amplitude of nystagmus being lower in primary position. Our findings are helpful in the clinical identification of IIN and genetic counselling of nystagmus patients.

An audit of the outcome of amblyopia treatment: a retrospective analysis of 322 children

Background/aims Little is known about the effectiveness of occlusion therapy in hospital settings. A retrospective analysis was conducted to assess modalities, outcome and hospital costs of children treated for amblyopia with patching in a UK clinic. Methods Notes of 322 children with amblyopia discharged after occlusion treatment were selected consecutively and reviewed. Data collated included age at presentation, amblyopia type, visual acuity (VA; before/after occlusion and at discharge), number of prescribed hours of occlusion, duration of patching treatment, number of glasses prescribed and number of visits attended or failed to attend. Hospital treatment costs were estimated. Results Mixed amblyopes were prescribed the longest amount of patching (mean 2815 h over 23 months) followed by strabismic (1984 h) and anisometropic (1238 h) amblyopes. 319 amblyopes received glasses and five atropine treatment. The percentage of patients reaching VA of 6/12 was best in the anisometropic and strabismic groups (>75%) and worse in mixed amblyopia (64%). Average hospital costs were estimated at £1365. Conclusion Although the mean duration of treatment was long, involving many hospital visits, the visual outcome was variable, unsatisfactory (<6/9) and more expensive than necessary. As compliance has been identified as a major problem methods to improve amblyopia treatment are needed, possibly by using educational/motivational intervention.