Search Results (3)

D-waves (also called direct waves) result from the direct activation of fast-conducting, thickly myelinated corticospinal tract (CST) fibres after a single electrical stimulus. During intraoperative neurophysiological monitoring, D-waves are used to assess the long-term motor outcomes of patients undergoing surgery for intramedullary spinal cord tumours, selected cases of intradural extramedullary tumours and surgery for syringomyelia. In the present manuscript, we discuss D-wave monitoring and its role as a tool for monitoring the CST during spinal cord surgery. We describe the neurophysiological background and provide some recommendations for recording and stimulation, as well as possible future perspectives. Further, we introduce the concept of anti D-wave and present an illustrative case with successful recordings. Full article

Background and Objectives: Intramedullary spinal cord tumors (IMSCT) are rare entities. A location in the upper cervical spine as a highly eloquent region carries the risk of postoperative neurological deficits, such as tetraparesis or respiratory dysfunction. Evidence for respiratory dysfunction is scarce. This study aimed to describe these highly eloquent tumors’ early and late postoperative clinical course. Materials and Methods: This is a single-center retrospective cohort study. We included 35 patients with IMSCT at levels of the craniocervical junction to C4 who underwent surgical treatment between 2008 and 2022. The authors analyzed the patients’ preoperative status, tumor- and surgery-specific characteristics, and follow-up functional status. Results: The study cohort included twenty-two patients with grade II ependymoma (62.9%), two low-grade astrocytomas (5.7%), two glioblastomas (5.7%), six hemangioblastomas (17.1%), two metastases (5.7%), and one patient with partially intramedullary schwannoma (2.9%). Gross total resection was achieved in 76% of patients. Early dorsal column-related symptoms (gait ataxia and sensory loss) and motor deterioration occurred in 64% and 44% of patients. At a follow-up of 3.27 ± 3.83 years, 43% and 33% of patients still exhibited postoperative sensory and motor deterioration, respectively. The median McCormick Scale grade was 2 in the preoperative and late postoperative periods, respectively. Only three patients (8.6%) developed respiratory dysfunction, of whom, two patients, both with malignant IMSCT, required prolonged invasive ventilation. Conclusions: More than 60% of the patients with IMSCT in the upper cervical cord developed new neurological deficits in the immediate postoperative period, and more than 40% are permanent. However, these deficits are not disabling in most cases since most patients maintain functional independence as observed by unchanged low McCormick scores. The rate of respiratory insufficiency is relatively low and seems to be influenced by the rapid neurological deterioration in high-grade tumors. Full article

Intramedullary spinal cord metastases (ISCMs) are infrequent lesions. Their incidence is estimated to range from 0.9 to 2.1%, found in autopsies of cancer patients. However, as the life expectancy of malignant tumour patients constantly increases, the reported incidences of ISCMs are consequently rising. This report presents a case of the misdiagnosis of an anaplastic astrocytoma type of tumour due to its similarities to small-cell neuroendocrine carcinoma. Therefore, we would like to underline the importance of further investigation that could assist and support the surgeon in the making of the differential diagnosis. We present the clinical case of a 73-year-old woman with a solitary intramedullary spinal cord metastasis as the initial manifestation of a carcinoid type of tumour. The patient was admitted to our department while presenting a rapid onset of paraparesis. Magnetic resonance imaging was performed, which showed an intramedullary mass at the C2–C6 vertebral level with a heterogeneous contrast enhancement. In light of these findings, the patient underwent surgery for a partial tumour resection. The lesion resulted in being a small-cell neuroendocrine type of carcinoma. This peculiar type of tumour presents similar radiological characteristics to the anaplastic astrocytoma type, which is why our diagnostical mismatch occurred. This is the report of a rare case of solitary intramedullary spinal cord metastasis, which is the result of an initial presentation of a lung small-cell neuroendocrine type of carcinoma. We conclude that ISCMs should be regularly considered as a part of the differential diagnosis of intramedullary lesions, especially in the case of a rapid onset and deterioration of neurological symptoms. Full article