Is intraoperative electrocorticography (ECoG) for long-term epilepsy-associated tumors (LEATs) more useful in children?-A Randomized Controlled Trial.

OBJECTIVES: The utility of intraoperative electrocorticography (ECoG)-guided resective surgery for pediatric long-term epilepsy-associated tumors (LEATs) with antiseizure medication (ASM) resistant epilepsy is not supported by robust evidence. As epilepsy networks and their ramifications are different in children from those in adults, the impact of intraoperative ECoG-based tailored resections in predicting prognosis and influencing outcomes may also differ. We evaluated this hypothesis by comparing the outcomes of resections with and without the use of ECoG in children and adults by a randomized study. METHODS: From June 2020 to January 2022, 42 patients (17 children and 25 adults) with LEATs and antiseizure medication (ASM)-resistant epilepsy were randomly assigned to one of the 2 groups (ECoG or no ECoG), prior to surgical resection. The 'no ECoG' arm underwent gross total lesion resection (GTR) without ECoG guidance and the ECoG arm underwent GTR with ECoG guidance and further additional tailored resections, as necessary. Factors evaluated were tumor location, size, lateralization, seizure duration, preoperative antiepileptic drug therapy, pre- and postresection ECoG patterns and tumor histology. Postoperative Engel score and adverse event rates were compared in the pediatric and adult groups of both arms. Eloquent cortex lesions and re-explorations were excluded to avoid confounders. RESULTS: Forty-two patients were included in the study of which 17 patients were in the pediatric cohort (age < 18 years) and 25 in the adult cohort. The mean age in the pediatric group was 11.11 years (SD 4.72) and in the adult group was 29.56 years (SD 9.29). The mean duration of epilepsy was 9.7 years (SD 4.8) in the pediatric group and 10.96 (SD 8.8) in the adult group. The ECoG arm of LEAT resections had 23 patients (9 children and 14 adults) and the non-ECoG arm had 19 patients (8 children and 11 adults). Three children and 3 adults from the ECoG group further underwent ECoG-guided tailored resections (average 1.33 additional tailored resections/per patient.).The histology of the tailored resection specimen was unremarkable in 3/6 (50%).Overall, the commonest histology in both groups was ganglioglioma and the temporal lobe, the commonest site of the lesion. 88.23% of pediatric cases (n = 15/17) had an excellent outcome (Engel Ia) following resection, compared to 84% of adult cases (n = 21/25) at a mean duration of follow-up of 25.76 months in children and 26.72 months in adults (p = 0.405).There was no significant difference in seizure outcomes between the ECoG and no ECoG groups both in children and adults, respectively (p > 0.05). Additional tailored resection did not offer any seizure outcome benefit when compared to the non-tailored resections. CONCLUSIONS: The use of intraoperative electrocorticography in LEATs did not contribute to postoperative seizure outcome benefit in children and adults. No additional advantage or utility was offered by ECoG in children when compared to its use in adults. ECoG-guided additional tailored resections did not offer any additional seizure outcome benefit both in children and adults.

Cost-effective utilization of single photon emission computed tomography (SPECT) in decision making for epilepsy surgery.

PURPOSE: To investigate the utility of single photon emission computed tomography (SPECT) without subtraction and MRI co-registration in decision making for epilepsy surgery. METHODS: Patients with refractory epilepsy and nonlocalizing or discordant non-invasive data (clinical, long-term VEEG, and MRI) were subjected to interictal and ictal SPECT studies before planning invasive or surgical strategy. Final localization was based upon the preoperative information and seizure freedom after surgery. SPECT was considered to be useful for decision-making if it obviated the need for intracranial monitoring or influenced its planning. RESULTS: 61 patients (mean age, 25.1±8.3 years) underwent SPECT studies between January 2004 and December 2008. Twenty-two patients had mesial temporal lobe epilepsy (MTLE), 13 had neocortical temporal lobe epilepsy (NTLE), and 26 had extratemporal lobe epilepsy (ETLE). As compared to ETLE, SPECT provided more localizing information (77.3% vs 46.2%, p=0.006) and influenced the final decision-making (45.4% vs 11.53%, p=0.005) in a significantly higher number of patients with MTLE. SPECT was particularly useful in patients with lesional TLE and nonlocalizing ictal data and in those with dual pathologies. SPECT did not provide any additional information in patients having either TLE or ETLE with normal MRI. CONCLUSIONS: SPECT is useful in a selected group of patients and unlikely to provide additional information in others. By restricting its use in patients who are likely to be benefited, a cost-effective utilization strategy can be employed in countries with limited resources. Due to the small number, these findings need to be validated in a larger group of patients.

Fungal infections of the central nervous system in HIV-negative patients: experience from a tertiary referral center of South India.

OBJECTIVE: To describe the clinical, radiological, and cerebrovascular fluid (CSF) findings and the outcome of microbiologically or histopathologically proven fungal infections of the central nervous system (CNS) in HIV-negative patients. METHODOLOGY AND RESULTS: We identified definite cases of CNS mycosis by screening the medical records of our institute for the period 2000-2008. The clinical and imaging details and the outcome were abstracted from the medical records and entered in a structured proforma. There were 12 patients with CNS mycosis (i.e., 2.7% of all CNS infections treated in this hospital); six (50%) had cryptococcal infection, three (25%) had mucormycosis, and two had unclassified fungal infection. Four (33%) of them had diabetes as a predisposing factor. The common presentations were meningoencephalitis (58%) and polycranial neuritis (41%). Magnetic resonance imaging revealed hydrocephalus in 41% and meningeal enhancement in 25%, as well as some unusual findings such as subdural hematoma in the bulbocervical region, carpeting lesion of the base of the skull, and enhancing lesion in the cerebellopontine angle. The CSF showed pleocytosis (66%), hypoglycorrhachia (83%), and elevated protein levels (100%). The diagnosis was confirmed by meningocortical biopsy (in three cases), paranasal sinus biopsy (in four cases), CSF culture (in three cases), India ink preparation (in four cases), or by cryptococcal polysaccharide antigen test (in three cases). Out of the ten patients for whom follow-up details were available, six patients recovered with antifungal medications (amphotericin B, 1 mg/kg/day for the minimum period of 6 weeks) and/or surgical treatment. Four patients expired (only one of them had received antifungal therapy). CONCLUSIONS: Most patients with CNS mycosis recover with appropriate therapy, but the diagnosis and management of these rare infections remains a challenge to clinicians.

Susceptibility-weighted imaging in differentiating bilateral medial thalamic venous and arterial infarcts.

Bilateral medial thalamic infarcts may be due to thrombosis of internal cerebral veins or occlusion of artery of Percheron. Conventional MR imaging is often not helpful in differentiating the two. We discuss two cases in whom susceptibility-weighted imaging, including phase images contributed in demonstrating the thrombosed or patent internal cerebral veins.