Absolute and relative predictor values of some non-invasive and invasive studies for the outcome of anterior temporal lobectomy.

BACKGROUND: There is controversy in the literature regarding the strategy used to obtain better outcomes after performing an anterior temporal lobectomy (ATL). Some investigators prefer to reduce the risks and costs of the predictor studies despite the fact that the number of patients cured after ATL (no seizures with no medication) is relatively small. Other investigators prefer to attempt a total cure in all patients by using all available predictor studies regardless of risks and costs. The latter strategy was the aim of the present work. METHODS: The absolute (%) and relative (ratio differences) predictor values of non-invasive and invasive studies for the outcome 24 months post-ATL were determined on 22 patients suffering from intractable non-lesional temporal lobe epilepsy. RESULTS: Under these conditions, 11 (50%) patients had excellent outcomes (seizure-free, no medication), 8 ( 36%), good outcomes (only auras with medication), and 3 (13.6%), poor ou tcomes (1 with >70%-seizure reduction and two no changes in seizure frequency). Predictors of excellent (vs. poor outcome) include the following: complex partial seizures (CXP) alone or associated with secondary generalized tonic-clonic seizures; ictal motionless stare and postictal amnesia; abnormal bitemporal spikes (prominent ipsilateral to ATL) and secondary bilateral synchrony EEG activities; focal hippocampal ictal EEG activities, and the presence of focal anterior temporal delta EEG activity 3 months after ATL. Predictors of poor (vs. excellent) outcomes include the following: CXP associated with other generalized seizure types; CTS, MRI, and EEG extratemporal abnormalities, and generalized basotemporal ictal EEG activities and the presence of seizures and focal anterior temporal spikes 3 months after ATL. CONCLUSIONS: The present study corroborates that no single predictive study (including non-invasive MRI and invasive ictal EEG activity) is predictive of the success or failure of ATL. Rather, a concordant combination of non-invasive and invasive studies is more likely to be predictive of a high probability of success. The high efficiency of ATL (86% of patients seizure-free) was accomplished by using all available predictor studies.

Persistence of the typical spike-wave EEG pattern after surgical excision of a temporal lobe astrocytoma and apical lobectomy.

This is a report on a patient with intractable 'primary' generalized seizures and typical spike-wave EEG patterns, in whom an unexpected temporal lobe astrocytoma was detected by MRI studies. Clinical and electrophysiological studies were performed before and after surgical excision of the tumor and apical temporal lobectomy in an attempt to determine whether 'primary' generalized seizures and EEG patterns and the temporal lobe tumor were only coincident neurological disorders or were indeed related. Before resection, the patient consistently showed a typical spike-wave EEG pattern with no background and paroxysmal activities suggestive of 'secondary' bilateral synchrony in 10 consecutive conventional EEG recordings; neither spontaneous interictal nor ictal ECoG activities suggested focal temporal lobe epileptogenesis. After resection, the patient showed increased pentylenetetrazol (PTZ) convulsive threshold, and reduction in the number of 'primary' generalized seizures, although typical spike-wave EEG discharges persisted. These observations suggest that 'primary' generalized seizures, EEG patterns and the temporal tumor were physiopathologically interrelated, and that both reticulocortical and corticoreticular mechanisms may participate together in the genesis of 'primary' generalized clinical and EEG activities.

Electroencephalographic and magnetic resonance correlations in children with intractable seizures of Lennox-Gastaut syndrome and epilepsia partialis continua.

A study was performed of EEG-magnetic resonance imaging (MRI) abnormalities in 7 Lennox-Gastaut syndrome (LGS) children and 3 epilepsia partialis continua (EPC) children with intractable generalized and partial motor seizures, respectively. In 4 children with LGS and 3 children with EPC, depth electrodes were implanted in the centromedian thalamic nuclei (CM) for seizure control. In all children with LGS, hyperdense, T2-weighted MRI signals were observed at the mesencephalic level of the brainstem, whereas none of the 3 children with EPC had this finding. Patients with idiopathic LGS without cerebral hemisphere MRI abnormalities showed generalized bilateral and symmetrical spike-wave EEG activity. Patients with symptomatic LGS with unilateral hemispheric MRI abnormalities demonstrated asymmetrical EEG activity with higher amplitude spike-and-wave over the normal hemisphere. Patients with EPC with unilateral hemispheric lesions had lateralized higher amplitude spike-wave over the damaged hemisphere. These data suggest that abnormal mesencephalic MRIs are a sign of bad prognosis in patients with LGS but not with EPC. Maximal amplitude paroxysmal EEG activities may indicate the abnormal hemisphere in patients with EPC or the normal hemisphere in those with LGS.

ACTH secreting pituitary microadenomas disclosed only by gadolinium DTPA enhanced MRI.

PURPOSE: To assess the usefulness of Gd-DTPA enhancement in disclosing microadenomas of the pituitary gland that had not been demonstrated by non enhanced MRI in patients with Cushing's disease. METHODS: Six patients with Cushing's disease underwent pre and post enhancement MRI scanning and the findings were correlated at surgery and confirmed by histological and immunohistochemistry studies of the surgical specimen. RESULTS: In all cases post enhancement MR scans demonstrated circumscribed hypointense foci that corresponded well with the location and extension of the adenomatous tissue found at surgery. Selective removal of the microadenomas failed to improve the clinical and laboratory abnormalities in two of the six patients. Such cases did not present residual hypointense foci in the post-operative Gd-DTPA enhanced MRI. CONCLUSION: Results suggest that Gd-DTPA enhanced MRI is useful to detect pituitary microadenomas; however, the abnormalities of the pituitary tissue may extend beyond the abnormal imaging.

Quiste epidermoide hipotalámico e hiperprolactinemia secundaria / Hypotalamic epidermoid cyst and secundary hyprprolactinemia

La hiperprolactinemia secudaria a tumor hipotalámo es una patología poco frecuente de gran interés clínico. Se presenta el caso de una mujer de 32 añosde edad con padecimiento de siete meses de evolución manifestado por cefalea intermitente, disminución de la agudeza visual, amenorrea y galactorrea. Posteriormente inicia poliuria, polidipsia, hiperfagia, aumento ponderal y trastornos del sueño. a la exploración física se encontró defecto campimétrico visual, alteración de los pares craneales I, II, III y VII y lesión piramidal. Los estudios hormonales fueron compatibles con diabetes insípida y síndrome hiperprolactinémico. La tomografía computada evidenció la presencia de tumoración hipotalámica hiperémica con componenete quístico. La paciente fue intervenida quirúrgicamente, encontrándose tumor quístico de la línea media de la región hipotalámica, el cual no pudo ser extirpado en su totalidad, reportándose como diagnóstico anatomopatológico definitivo quiste epidermoide de la línea media. La evolución postquirúrgica de la paciente fue mala, fallecido 48 horas después de la cirugía.