Síndrome de uno y medio / One and a half syndrome

Se realizó una revisión bibliográfica con el objetivo de obtener información actualizada acerca de las características, diagnóstico y tratamiento del síndrome del uno y medio. Se emplearon principalmente las bases de datos disponibles en Infomed, Google Scholar y Pubmed. El síndrome del uno y medio es una entidad infrecuente, que se caracteriza por parálisis de la mirada conjugada horizontal y alteración del fascículo longitudinal medial ipsilateral secundario a diversas etiologías, entre las que se incluyen la enfermedad cerebrovascular y la esclerosis múltiple. Clínicamente se presenta con exotropía y nistagmo a la abducción. Su diagnóstico puede ser establecido en la exploración por las alteraciones típicas de los movimientos oculares, mientras que la imagen de resonancia magnética cerebral resulta indispensable para el diagnóstico diferencial y etiológico(AU)

One and a half syndrome is an infrequent condition characterized by conjugate horizontal gaze palsy and ipsilateral medial longitudinal fasciculus alteration secondary to various etiologies, including cerebrovascular disease and multiple sclerosis. Clinically, it presents with exotropia and abduction nystagmus. Its diagnosis may be established during exploration, due to the typical eye movement alterations, whereas brain magnetic resonance imaging is indispensable for differential and etiological diagnosis. A bibliographic review was conducted to obtain updated information about the characteristics, diagnosis and treatment of one and a half syndrome. Use was made of the databases available in Infomed, Google Scholar and Pubmed(AU)

Fisher one-and-a-half syndrome due to a bulb protuberance cavernoma. / Síndrome del uno y medio de Fisher a causa de un cavernoma bulbo-protuberancial.

The one and a half Fisher syndrome is produced by an unilateral lesion in the dorsal and inferior part of the pons located specifically in the pontine tegmentum. This is an area that contains the medial longitudinal fasciculus (LMF), the paramedian pontine reticular formation (PPRF) and the nucleus of the sixth cranial nerve, responsible for the horizontal movements of the gaze. Clinically it manifests with conjugate gaze palsy with internuclear ophthalmoplegia. The case is reported on a 60 year-old patient, who presented with binocular diplopia, ophthalmoplegia and paralysis of the gaze conjugated to the left. Imaging studies were performed that showed a hemi-protuberant haematoma secondary to a cavernoma. As expected, he presented with several episodes of re-bleeding with clinical worsening: headache, diplopia, tetraparesis, and hypoaesthesia in the right side of the face, as such that the microsurgical exeresis of the protuberant cavernoma was considered.

Síndrome del uno y medio secundario a ataque cerebrovascular isquémico vertebrobasilar / One and half syndrome after ischemic vertebrobasilar stroke

El síndrome del uno y medio es una entidad que se caracteriza por parálisis de la mirada conjugada horizontal y alteración del fascículo longitudinal medial (FLM) ipsilateral secundario a diversas etiologías, entre las que se incluye el ataque cerebrovascular (ACV). Se describen dos casos de pacientes que consultaron por hemiparesia, incapacidad para realizar movimientos horizontales en uno de los ojos y abducción forzada del ojo contralateral e imposibilidad para la aducción. En ambos casos los estudios demostraron la presencia de un ACV isquémico vertebrobasilar como origen del síndrome; el reconocimiento de la fisiología de la mirada conjugada es fundamental en el abordaje del paciente y permite realizar un diagnóstico exacto a partir de una historia clínica detallada y una evaluación física minuciosa.

The One and a Half Syndrome is a condition characterized by paralysis of the horizontal conjugate gaze and a ipsilateral internuclear ophthalmoplegia secondary to other processes such as a stroke. We describe two cases of patients that had hemiparesis, inability to perform horizontal movements in one eye and forced abduction of the contralateral eye with inability to adduct it. With the corresponding study of both cases it was possible to diagnose a vertebrobasilar ischemic stroke as the origin of the syndrome; the recognition and understanding of the physiology of the conjugate gaze is crucial in the approach of the patients and allow an accurate diagnosis using a detailed history and a thorough physical evaluation.