Botulinum toxin in motor disorders: practical considerations with emphasis on interventional neurophysiology.

After a brief review of the pharmacological properties of the botulinum toxin (BT), its mechanism of action on the nerve endings of the neuromuscular junctions, and the general therapeutic principles and adverse side effects, we discuss the advantages of interventional neurophysiology for the treatment of focal motor disorders by means of botulinum toxin A (BTA) muscle infiltration. Electromyography (EMG) provides a valuable objective information in the diagnosis of many motor disturbances and enables the precise identification of the muscles that contribute to the abnormal movement or posture. The use of EMG guidance for BTA injection seems advisable in every muscle but it become indispensable in those difficult to access, deeply located or partially atrophied by previous toxin infiltrations. The EMG study also serves to localise the areas with the highest abnormal activity and the motor point of the muscle, where the injection of toxin exerts its maximal effect. Consequently, lower doses of BTA can be employed without decreasing the efficacy of treatment but reducing the potential risk of side effects, antibody production and the cost of treatment. Electrophysiological diagnosis and BTA treatment may be performed during the same exploration. Considerations on the particular aspects and lines of action are given referring to the main focal muscular hyperactivity motor disorders such as cervical, oromandibular and laryngeal dystonias, blepharospasm, writer's cramp, hemifacial and hemimasticatory spasms, infantile and adult forms of spasticity and some other focal disturbances such as strabismus, detrusor-sphincter dyssynergia and anismus.

[Massive intratumoral haemorrhage as a clinical presentation of acoustic neuroma]. / Hemorragia intratumoral masiva como presentación de neurinoma del acústico.

INTRODUCTION: Acoustic neurinoma presenting as massive intratumoural hemorrhage is quite an uncommon entity, with less than 40 clinical reports in the literature. Secondary mass effect compressing the brain stem may be a life threatening condition. CASE REPORT: A 38 years old male was admitted at our hospital with several cranial nerve palsies on the right side and decreased level of consciousness (GCS 5) of acute onset. On cranial computed tomography a great haematoma was found in the right cerebello pontine angle, appearing to be an intratumoural bleeding. Emergency surgery was performed with complete removal of the haematoma and of the tumour related to the VIII cranial nerve, which was diagnosed as hypervascularized schwannoma. Clinical outcome was good. CONCLUSIONS: Intratumoural hemorrhage in acoustic neurinomas is rare, appearing mostly in those tumours measuring more than 3 cm and with increased vascularity. In general they manifest with subtle neurological deficits. Acute neurological deterioration with decrease in consciousness level although exceptional may be associated to great mortality rates. The treatment of choice is the complete removal of the haematoma and the tumour, in one surgery if possible. Prognosis is good in most cases, with morbidity consisting on cranial nerve palsies. Hypoglossal facial anastomosis may restore at least partial facial function. Neurophysiology tests give a clear measurement of cranial nerve lesions and their evolution with treatments.

Hemorragia intratumoral masiva como presentaciónde neurinoma del acústico / Massive intratumoral haemorrhage as a clinical presentation of acoustic neuroma

Introducción. La hemorragia intratumoral masiva es extraordinariamente rara como clínica de presentación en los neurinomas del VIII par, habiéndose publicado menos de 40 casos en la literatura. El efecto de masa producido por el sangrado sobre el tronco cerebral puede suponer un riesgo vital para el paciente. Caso clínico. Varón de 38 años que ingresó por una afectación brusca de múltiples pares craneales derechos y un progresivo deterioro de consciencia (GCS 5). En la tomografía computarizada craneal se evidenció un gran hematoma en el ángulo pontocerebeloso derecho en el seno de un tumor. Inmediatamente se realizó la evacuación del hematoma y la resección completa del tumor dependiente del VIII par que, histológicamente, se describió como schwannoma hipervascularizado. La evolución fue favorable. Discusión. El sangrado intratumoral en los neurinomas del acústico es infrecuente; aparece fundamentalmente en tumores mayores de 3 cm y con una hipervascularización anómala. Ocasionalmente existen factores desencadenantes del sangrado. En general cursan con déficit neurológicos discretos. La presentación como deterioro agudo de conciencia es excepcional, pero aparece asociada a una mayor mortalidad. El tratamiento de elección es la evacuación del hematoma y la resección tumoral completa en el mismo tiempo quirúrgico si es posible. El pronóstico vital es bueno, y como secuelas habituales quedan lesiones en los pares craneales, que pueden beneficiarse de cirugías de reinervación (anastomosis hipoglosofacial). Los estudios neurofisiológicos permiten objetivar la evolución de la afectación neurológica (AU)