Intraspinal pilocytic astrocytomas: An overview and 2-D illustrative resection technique video.

BACKGROUND: Spinal cord pilocytic astrocytomas (PAs) are rare and typically occur in pediatric patients. While PAs are often well-circumscribed and amenable to gross total resection, they sometimes harbor infiltrative components that can invade normal cord parenchyma. METHODS: Here, we present a 59-year-old female with a progressive right-sided hemi-sensory loss, right-sided hemiparesis, and gait imbalance. The preoperative T2 magnetic resonance imaging revealed a large loculated cystic tumor that focally compressed the dorsal medulla, while the contrast study revealed a 1.3 cm homogenously enhancing expansile intramedullary mass centered at the C1 level. RESULTS: The patient underwent a C1-2 laminectomy followed by gross total intramedullary tumor resection utilizing intraoperative dorsal column mapping. There were no operative complications. The patient had preserved motor strength and an expected dorsal column dysfunction, which largely resolved over 9 months postoperatively. CONCLUSION: Here, we provide a broad overview of PAs, in addition to a case study/technical note that includes a 2-D intraoperative video detailing the resection technique.

Aspiration of sterile post-operative spinal fluid collections using low-dose computed tomography guidance.

Sterile postoperative seromas can develop after posterior spinal surgery and cause pain, weakness, and numbness. Management typically involves operative evacuation. We propose that these collections can be managed with percutaneous computed tomography (CT) guided aspiration, potentially saving the patient an additional surgery. Here, we evaluate the safety and efficacy of this approach. Patients who developed symptomatic postoperative seromas within 60 days following surgery for spinal canal stenosis and had stable neurologic exams were considered for CT-guided percutaneous aspiration. To be considered for this approach, patients had to have pre-procedural evidence of radiographic spinal cord or cauda equina compression, hemodynamic stability, and low suspicion for infection. A total of 16 symptomatic collections were aspirated among 15 patients. The mean volume of fluid removed was 32.0 mL. There were no peri- or post-procedural complications. Eight (50%) had resolution or substantial improvement of their symptoms (p = 0.0002 when compared to the null hypothesis). One patient had short interval improvement but return of their initial symptoms 12 h following aspiration, 3/16 (19%) had minimal improvement, and 4/16 (25%) had no change in symptoms. Fluid collections that appeared denser on the pre-procedural CT were associated with retrieval of more sanguineous appearing fluid (p = 0.08). Neither the amount nor quality of fluid aspirated was associated with outcome. We conclude that percutaneous CT-guided aspiration of postoperative seromas is safe and should be considered as an alternative to open surgical evacuation in patients with stable neurologic exams.

Pitfalls in Diagnosis and Management of Testicular Choriocarcinoma Metastatic to the Brain: Report of 2 Cases and Review of Literature.

INTRODUCTION: Pure choriocarcinoma of the testes is a rare, aggressive germ cell tumor that can metastasize to the brain. Although its prognosis has improved with the development of cisplatin-based chemotherapy regimens, cerebral metastases are prone to hemorrhage and associated with high morbidity. Here, we present 2 cases of testicular choriocarcinoma with cerebral metastasis and discuss potential pitfalls in their diagnosis and management. We also review cases in the literature that feature these rare lesions. METHODS: Medline was searched for all publications including the terms "testicular choriocarcinoma" and "cerebral metastasis" or "brain metastasis." Articles that included patients with tumors classified as a mix of choriocarcinoma and other germ cell tumor subtypes were excluded. RESULTS: A total of 15 cases from the literature and our own 2 cases were included in the analysis. The mean age at presentation was 25.5 years. Neurologic symptoms accounted for the initial presentation of 9 patients (60%). Outcomes were predominantly poor, with 10 patients (67%) expiring shortly after their initial diagnosis. Three of these deaths were related to mass effect from metastasis-related hemorrhages. Two patients underwent emergent decompressive craniectomies, and both died from cerebral herniation. CONCLUSION: The potentially catastrophic nature of choriocarcinoma-related cerebral hemorrhages underscores the need for prompt, accurate diagnosis and aggressive surgical management of these lesions. Their highly vascular nature and lack of findings on cerebral angiography may cause them to be confused with occult vascular malformations.

Primary lung metastasis of glioblastoma multiforme with epidural spinal metastasis: Case report.

Extracranial metastasis of glioblastoma multiforme (GBM) is rare, but has recently been reported with increasing frequency. GBM metastases typically present after a biopsy or resection of the primary tumor. An otherwise healthy 54year-old woman presented with recurring pleural effusions originally believed to be from a primary lung malignancy. The patient subsequently experienced a generalized tonic clonic seizure and a right temporal brain mass was discovered. The patient later developed weakness and radiculopathy, and an extramedullary extradural mass spreading from C7 to T6 was discovered. She underwent resection of both central nervous system lesions as well as a lung biopsy, and all pathologic specimens were consistent with GBM. The case presented is unique in that the patient's initial symptoms were related to her metastasis. Furthermore, a purely epidural spread of GBM that respects the leptomeninges and intramedullary parenchyma is highly unusual.

A Prediction Model for Functional Outcomes in Spinal Cord Disorder Patients Using Gaussian Process Regression.

Predicting the functional outcomes of spinal cord disorder patients after medical treatments, such as a surgical operation, has always been of great interest. Accurate posttreatment prediction is especially beneficial for clinicians, patients, care givers, and therapists. This paper introduces a prediction method for postoperative functional outcomes by a novel use of Gaussian process regression. The proposed method specifically considers the restricted value range of the target variables by modeling the Gaussian process based on a truncated Normal distribution, which significantly improves the prediction results. The prediction has been made in assistance with target tracking examinations using a highly portable and inexpensive handgrip device, which greatly contributes to the prediction performance. The proposed method has been validated through a dataset collected from a clinical cohort pilot involving 15 patients with cervical spinal cord disorder. The results show that the proposed method can accurately predict postoperative functional outcomes, Oswestry disability index and target tracking scores, based on the patient's preoperative information with a mean absolute error of 0.079 and 0.014 (out of 1.0), respectively.

Quantitative assessment of hand motor function in cervical spinal disorder patients using target tracking tests.

Cervical spondylotic myelopathy (CSM) is a chronic spinal disorder in the neck region. Its prevalence is growing rapidly in developed nations, creating a need for an objective assessment tool. This article introduces a system for quantifying hand motor function using a handgrip device and target tracking test. In those with CSM, hand motor impairment often interferes with essential daily activities. The analytic method applied machine learning techniques to investigate the efficacy of the system in (1) detecting the presence of impairments in hand motor function, (2) estimating the perceived motor deficits of CSM patients using the Oswestry Disability Index (ODI), and (3) detecting changes in physical condition after surgery, all of which were performed while ensuring test-retest reliability. The results based on a pilot data set collected from 30 patients with CSM and 30 nondisabled control subjects produced a c-statistic of 0.89 for the detection of impairments, Pearson r of 0.76 with p < 0.001 for the estimation of ODI, and a c-statistic of 0.82 for responsiveness. These results validate the use of the presented system as a means to provide objective and accurate assessment of the level of impairment and surgical outcomes.