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Background Paramyotonia congenita (PMC) is a skeletal muscle channelopathy caused by mutations in the SCN4A gene, characterised by cold-sensitive muscle stiffness that paradoxically worsens with repetitive action. Strabismus, an additional feature which may be seen in childhood, remains poorly described in the literature with limited guidance on optimal monitoring and treatment approaches.Methods A retrospective review of case notes was conducted for patients with genetically confirmed PMC treated at the Great Ormond Street Hospital for Children Channelopathy Service. Data were collected on symptom onset, ophthalmic assessments, responses to pharmacological treatments, surgical outcomes, and follow-up details.Results Among 24 patients, 11 were affected by strabismus, predominantly esotropia, with onset between 6 months and 5 years of age. Strabismus was frequently associated with amblyopia. Pharmacological treatment of the paramyotonia did not necessarily lead to improvement of the strabismus. Five patients underwent corrective surgery, achieving outcomes comparable to those reported in non-PMC strabismus cases, with improvement of amblyopia.Conclusion Strabismus and associated amblyopia are common in paediatric PMC, highlighting the need for routine ophthalmologic evaluations in these patients. This study is limited by its retrospective nature and small sample size, prospective studies are needed to better understand this association and optimise management strategies.murva30593@hotmail.com