Linear accelerator radiosurgery in treatment of central neurocytomas.

OBJECTIVES: The purpose of this report was to review our experience with stereotactic radiosurgery in the management of patients with residual neurocytomas after initial surgery. METHODS: Between October 1996 and December 2001, four patients with central neurocytoma were treated by surgery and subsequently underwent linear accelerator (LINAC) radiosurgery. RESULTS: Two of the patients were cured, one exhibited a significant reduction in tumour size and the fourth remains stable. All four patients are alive and well. CONCLUSIONS: In cases of small residual tumours or recurrences radiosurgery allows open surgery to be avoided and is a safe and potentially effective approach.

[Diagnosis of mesial temporal sclerosis with magnetic resonance imaging]. / El diagnóstico de la esclerosis temporal mesial mediante imagen de resonancia magnética.

INTRODUCTION: Mesial temporal sclerosis (MTS) is a progressive drug-resistant epileptic syndrome which requires rapid, effective diagnosis and treatment. Histologically there is atrophy and gliosis of the hippocampus. OBJECTIVE: To establish magnetic resonance (MR) imaging guidelines for correct diagnosis. PATIENTS AND METHODS: We made a prospective study of 78 patients with drug-resistant temporal lobe epilepsy (44 women and 34 men; age 6-66 years, mean 31 years). Using a magnet of 1.5 Teslas paracoronal sections were made of the hippocampus with T1 volumetric with inversion-recovery, FLAIR (fluid-attenuated inversion-recovery) and T2 relaxometry. A control group of 30 healthy volunteers was established. The reduction in volume and hippocampal T2 hyperintensity were considered to be MTS diagnosed on MR. RESULTS: No hippocampal differences were observed among the healthy volunteers. The confidence intervals (mean +/- 1.96 SD) were: right volume: 4.169-5.911 mm3; left volume: 4.097-5.940 mm3; time of T2 relaxation: 98-113 ms. MTS was observed in 42 patients (54%): 24 left, 14 right and four asymmetrical bilateral. The results of the diagnostic validity (sensitivity/specificity) were: T1 volumetric 91/92%, FLAIR 93.5/98% and T2 relaxometry 91/92%. There was atrophy of other extrahippocampal structures in five cases of MTS; 10 patients with MTS (23.5%) had another extrahippocampal lesion associated (dual pathology), particularly migration disorders; 21 patients (27%) had lesions without MTS (tumors, alterations of migration, nonspecific gliosis) and in 15 cases (19%) there were no abnormal findings. A total of 27 patients were operated on: 22 with MTS (21 had diagnostic MR, one case had no abnormal findings), four cases had tumors and one had cortical dysplasia. CONCLUSION: The combination of quantitative techniques (T1 volumetric with inversion-recovery and T2 relaxometry) and FLAIR optimize MTS diagnosis using MR.

El diagnóstico de la esclerosis temporal mesialmediante imagen de resonancia magnética / The diagnosis of mesial temporal sclerosis by magnetic resonance imaging

Introducción. La esclerosis temporal mesial (ETM) es un síndrome epiléptico farmacorresistente, progresivo y que requiere diagnóstico y tratamiento rápidos y eficaces. Histológicamente presenta atrofia y gliosis del hipocampo. Objetivo. Establecer un protocolo de imagen de resonancia magnética (RM) para su diagnóstico correcto. Pacientes y métodos. Realizamos un estudio prospectivo de 78 pacientes con epilepsia del lóbulo temporal farmacorresistente (44 mujeres y 34 varones; edad: 6-66 años, media: 31 años). Con imán de 1,5 Teslas se realizaron cortes paracoronales a hipocampos con volumetría-T1 con inversión-recuperación, FLAIR (fluid-attenuated inversion-recovery) y relaxometría-T2. Se estableció un grupo control de 30 voluntarios sanos. Se consideró ETM por RM la disminución de volumen e hiperintensidad-T2 hipocampal. Resultados. En los voluntarios sanos no existieron diferencias entre hipocampos. Los intervalos de confianza (media ñ 1,96 DE) fueron: volumen derecho: 4.169-5.911 mm3; volumen izquierdo: 4.097-5.940 mm3; tiempo de relajación T2: 98-113 ms. Se detectó ETM en 42 pacientes (54 por ciento): 24 izquierdas, 14 derechas y cuatro bilaterales asimétricas. Los resultados de validez diagnóstica (sensibilidad/especificidad) fueron: volumetría-T1 91/92 por ciento, FLAIR 93,5/98 por ciento y relaxometría-T2 91/92 por ciento. Cinco casos de ETM presentaron atrofia de otras estructuras extrahipocampales; 10 pacientes con ETM (23,5 por ciento) asociaron otra lesión extrahipocampal (patología dual), sobre todo alteraciones de migración; 21 pacientes (27 por ciento) mostraron lesiones sin ETM (tumores, alteraciones migracionales, gliosis inespecíficas) y 15 casos (19 por ciento) no mostraron hallazgos. Un total de 27 pacientes fueron intervenidos: 22 con ETM (21 con RM diagnóstica y un caso sin hallazgos), cuatro con tumores y uno con displasia cortical. Conclusión. La combinación de técnicas cuantitativas (volumetría-T1 con inversión-recuperación y relaxometría-T2) y FLAIR optimiza el diagnóstico de ETM mediante RM (AU)