Premanifest Huntington's disease: Examination of oculomotor abnormalities in clinical practice.

INTRODUCTION: Different oculomotor abnormalities have been reported to occur in premanifest Huntington's disease. The aim of this study is to investigate which oculomotor items of the Unified Huntington's Disease Rating Scale (UHDRS) are affected in premanifest individuals compared to healthy controls, and if CAG repeat length and age are correlated with oculomotor abnormalities in premanifest Huntington's disease gene carriers. METHODS: We compared baseline data of 70 premanifest individuals and 27 controls who participated in the Enroll-HD study at the Leiden University Medical Center, the Netherlands. Premanifest gene carriers were divided in individuals near to disease onset and individuals far from disease onset. RESULTS: Using a logistic regression model, only horizontal ocular pursuit of the six oculomotor items of the UHDRS was significantly more frequently affected in premanifest individuals close to disease onset compared to controls (p = 0.044, OR 13.100). Age was significantly higher in premanifest individuals with affected horizontal ocular pursuit (p = 0.016, OR 1.115) and with affected vertical ocular pursuit (p = 0.030, OR 1.065) compared to premanifest individuals without ocular pursuit deficits. CONCLUSIONS: Our results suggest that horizontal ocular pursuit is the only affected oculomotor item of the UHDRS in premanifest individuals and could be used to assess early clinical signs of Huntington's disease. Saccade initiation and saccade velocity do not seem useful for detecting differences between premanifest individuals and controls.

Parálisis de la mirada horizontal y escoliosis progresiva en un paciente con endotropia congénita y limitación de abducción. A propósito de un caso / Horizontal gaze palsy and progressive scoliosis in a patient with congenital esotropia and inability to abduct. A case report

CASO CLÍNICO: Presentamos el caso de un paciente varón de 4 años de edad, remitido por endotropia congénita con limitación de abducción, tortícolis horizontal con fijación cruzada y escoliosis toraco-lumbar. El análisis genético del gen ROBO3 confirmó el diagnóstico de parálisis de la mirada horizontal y escoliosis progresiva (HGPPS). DISCUSIÓN. La HGPPS es una alteración infrecuente de la motilidad ocular, caracterizada por ausencia de movimientos conjugados horizontales y escoliosis progresiva de inicio precoz. Esta entidad debe ser considerada como parte del diagnóstico diferencial de la endotropia congénita con fijación cruzada e incapacidad de abducción

CASE REPORT: The case is presented on a 4-year-old child with congenital esotropia, limitation of abduction, cross-fixation, and thoracolumbar scoliosis. Genetic testing of ROBO3 gene confirmed the diagnosis of horizontal gaze palsy and scoliosis (HGPSS). DISCUSSION: HGPPS is a rare congenital disorder characterised by absence of conjugate horizontal eye movements and progressive scoliosis developed in childhood and adolescence. We highlight this motility disorder as a part of the differential diagnosis of early childhood esotropia with cross- fixation and limitation of abduction