Laser interstitial thermal therapy (LITT) for pediatric low-grade glioma-case presentations and lessons learned.

BACKGROUND: The surgical treatment of brain tumors has developed over time, offering customized strategies for patients and their specific lesions. One of the most recent advances in pediatric neuro-oncological surgery is laser interstitial thermal therapy (LITT). However, its effectiveness and indications are still being evaluated. The aim of this work is to review the current literature on LITT for pediatric low-grade gliomas (pLGG) and evaluate our initial results in this context. METHODS: We retrospectively reviewed our pediatric neurosurgery database for patients who received LITT treatment between November 2019 and December 2023. We collected data on the indications for LITT, technical issues during the procedure, and clinical and radiological follow-up. RESULTS: Three patients underwent 5 LITT procedures for pLGG. The lesion was thalamo-peduncular in one patient, cingulate in one, and deep parietal in one patient. Two patients had a previous open resection done and were diagnosed with pLGG. One patient underwent a stereotaxic biopsy during the LITT procedure that was non-diagnostic. The same patient underwent a later open resection of the tumor in the cingulate gyrus. There were no surgical complications and all patients were discharged home on the first post-operative day. The follow-up period was between 20 and 40 months. Radiological follow-up showed a progressive reduction of the tumor in patients with LGG. CONCLUSION: Laser interstitial thermal therapy is a minimally invasive treatment that shows promise in treating deep-seated pLGG in children. The treatment has demonstrated a reduction in tumor volume, and the positive results continue over time. LITT can be used as an alternative treatment for tumors located in areas that are difficult to access surgically or in cases where other standard treatment options have failed.

Optimization of Radiofrequency Needle Placement in Percutaneous Cordotomy Using Electromyography in the Deeply Sedated Patient.

BACKGROUND AND OBJECTIVES: Cordotomy, the selective disconnection of the nociceptive fibers in the spinothalamic tract, is used to provide pain palliation to oncological patients suffering from intractable cancer-related pain. Cordotomies are commonly performed using a cervical (C1-2) percutaneous approach under imaging guidance and require patients' cooperation to functionally localize the spinothalamic tract. This can be challenging in patients suffering from extreme pain. It has recently been demonstrated that intraoperative neurophysiology monitoring by electromyography may aid in safe lesion positioning. The aim of this study was to evaluate the role of compound muscle action potential (CMAP) in deeply sedated patients undergoing percutaneous cervical cordotomy (PCC). METHODS: A retrospective analysis was conducted of all patients who underwent percutaneous cordotomy while deeply sedated between January 2019 and November 2022 in 2 academic centers. The operative report, neuromonitoring logs, and clinical medical records were evaluated. RESULTS: Eleven patients underwent PCC under deep sedation. In all patients, the final motor assessment prior to ablation was done using the electrophysiological criterion alone. The median threshold for evoking CMAP activity at the lesion site was 0.9 V ranging between 0.5 and 1.5 V (average 1 V ± 0.34 V SD). An immediate, substantial decrease in pain was observed in 9 patients. The median pain scores (Numeric Rating Scale) decreased from 10 preoperatively (range 8-10) to a median 0 (range 0-10) immediately after surgery. None of our patients developed motor deficits. CONCLUSION: CMAP-guided PCC may be feasible in deeply sedated patients without added risk to postoperative motor function. This technique should be considered in a group of patients who are not able to undergo awake PCC.

Differentiating spinal pathologies by deep learning approach.

BACKGROUND CONTEXT: Spinal pathologies are diverse in nature and, excluding trauma and degenerative diseases, includes infectious, neoplastic (either extradural or intradural), and inflammatory conditions. The preoperative diagnosis is made with clinical judgment incorporating lab findings and radiological studies. When the diagnosis is uncertain, a biopsy is almost always mandatory since the treatment is dictated by the type of pathology. This is an invasive, timely, and costly process. PURPOSE: The aim of this study was to develop a deep learning (DL) algorithm, based on preoperative MRI and post-operative pathological results, to differentiate between leading spinal pathologies. STUDY DESIGN: We retrospectively collected and analyzed clinical, radiological, and pathological data of patients who underwent spinal surgery or biopsy for various spinal pathologies between 2008 and 2022 at a tertiary center. The patients were stratified according to their pathological reports (the threshold for inclusion was set to 25 patients per diagnosis). METHODS: Preoperative MRI, clinical data, and pathological results were processed by a deep learning model built on the Fast.ai framework on top of the PyTorch environment. RESULTS: A total of 231 patients diagnosed with carcinoma (80), infection (57), meningioma (52), or schwannoma (42), were included in our model. The mean overall accuracy was 0.78±0.06 for the validation, and 0.93±0.03 for the test dataset. CONCLUSION: Deep learning algorithm for differentiation between the aforementioned spinal pathologies, based solely on clinical MRI, proves as a feasible primary diagnostic modality. Larger studies should be performed to validate and improve this algorithm for clinical use. CLINICAL SIGNIFICANCE: This study provides a proof-of-concept for predicting spinal pathologies solely by MRI based DL technology, allowing for a rapid, targeted, and cost-effective work-up and subsequent treatment.

Shifting Strategies in the Treatment of Pediatric Craniopharyngioma.

PURPOSE OF REVIEW: Craniopharyngiomas represent one of the most challenging diseases to treat. Despite their benign histology, and after many decades of surgical experience and technological advancements, there is still no clear consensus regarding the most effective management for this tumor. Due to their location and aggressive local characteristics, purely surgical approaches all too often result in unacceptable morbidity. RECENT FINDINGS: Partial resection combined with radiation therapy results in similar control rates when compared to aggressive surgery, while also minimalizing the neuro-endocrinological morbidity. In this manuscript, we describe the historical progression of the shifting strategies in the management of pediatric craniopharyngioma. Time has also altered our expectations for outcomes, evolving from purely morbidity and mortality to simple Glasgow Outcomes Scales, now to formal neuro-psychometric and quality of life data.

Corynebacterium bovis surgical site infection and brain abscess: The first case report and literature review.

Corynebacterium bovis is a mainly zoonotic pathogen, a common cause of bovine mastitis. It is however rarely pathogenic in humans, with only few cases reported in the literature. We present the first reported case of neurosurgical site infection due to c.bovis, resulting in a brain abscess. A 75-year-old female presented with dysphasia resulting from lung metastases. She underwent surgical resection, and four months later presented with swelling, tenderness and crusted exudate over the surgical site. Mri revealed surgical site infection and brain abscess, therefore the patient underwent urgent surgery. C.bovis was isolated from all specimens sent from different locations. The patient received appropriate antibiotic treatment without sequela. C. Bovis is being increasingly reported as a cause of various human infections, and should not automatically be considered to be a mere contaminant. It is imperative to be certain, prior to the antibiotics treatment, that this particular isolate is likely to be the pathogen, as it can be evident when there are multiple positive cultures of this pathogen from several locations.

Ventriculosinus shunts: their role in selected patients.

OBJECTIVE: Ventriculoperitoneal shunt placement is the most common treatment for hydrocephalus. However, most patients will require multiple shunt revisions over time. In cases of peritoneal shunt failure, the pleura and heart are alternative distal sites. Sinus shunts have been described but are not commonly used. The potential vascular complications, as well as inexperience with these shunts, make these tools less attractive. The goal of this study was to share the authors' experience with ventriculosinus shunts (VSSs) in selected patients. METHODS: Between December 2018 and February 2022, a total of 7 patients (1 adult, 6 children) underwent 11 surgeries for the placement of a VSS at the authors' institution. Data regarding complications and shunt function were retrospectively collected and assessed, and a review of the literature was conducted. RESULTS: The mean (± standard deviation) age at surgery was 11.9 ± 12.8 years (range 1.3-38.2 years). All patients had had previous shunt systems that failed and systemic conditions that made other distal sites less desirable. In all cases, a low-pressure differential valve was installed. Over a mean follow-up of 18 ± 9.8 months (range 9-39 months), 4 of the 7 patients underwent additional shunt revisions, 2 of whom had shunts placed at other sites. One patient had symptomatic partial sinus thrombosis, managed conservatively. During follow-up, 5 patients showed improvement in their symptoms of high intracranial pressure using the VSS. There were no severe complications of air embolism, bleeding, or infection. CONCLUSIONS: VSSs may have a role to play in selected patients in whom more commonly used distal shunt locations have failed. Significant complications with these shunts are rare. Additional experience is needed to better understand the ideal catheter and placement locations.

Concurrent occurrence of squamous cell carcinoma in a cerebellopontine angle epidermoid cyst: A case report and review of the literature.

Background: Intracranial epidermoid cysts are rare benign lesions. Cases of malignant transformation (MT) into squamous cell carcinoma (SCC) have rarely been reported. We present a case of concurrent occurrence of SCC diagnosed during primary resection of epidermoid cyst (EC) and a relevant literature review. Case Description: A 61-year-old patient was diagnosed with a right cerebellopontine angle (CPA) lesion after suffering from vertigo, diplopia, and right trigeminal (V2) hypoesthesia. Brain magnetic resonance imaging (MRI) showed a lesion consistent with an EC, demonstrating restricted diffusion with rim-enhancing area on the medial side of the cyst. During resection, two different tissue pathologies were observed, one consistent with an epidermoid (which was completely removed) and an additional firm tissue adherent to the brainstem, preventing gross total resection. Pathological evaluation confirmed two separate histologies - epidermoid and SCC. The patient never recurred to complete the recommended radiotherapy. Eleven months following surgical resection, a follow-up MRI showed local massive recurrence of the enhancing lesion. He was, further, treated with radiotherapy and is currently being followed up. Conclusion: MT of an intracranial EC to SCC is rare and associated with poor prognosis. SCC may be found incidentally at time of primary resection or arise from a remnant of previously operated EC. Thus, aggressive complete resection should be intended, and separate pathological specimens should be sent from any abnormal region of the tumor.

Nocardia cyriacigeorgica brain abscess in a patient on low dose steroids: a case report and review of the literature.

BACKGROUND: Nocardia cyriacigeorgica was first described in 2001. It is an emerging pathogen that mainly affects immunocompromised patients. A brain abscess caused by N. cyriacigeorgica has been reported only in immunocompromised hosts. We present a rare case of brain abscess caused by N. cyriacigeorgica in an adult male receiving low dose steroids. CASE PRESENTATION: A 75-year-old male weekend gardener without an immunocompromising condition presented with neurological complaints that were initially attributed to an ischemic stroke. Due to the unusual presentation and rapid progression, his condition was thought to be caused by a cerebral space-occupying lesion. He underwent an emergent right-sided parietal craniotomy and the histopathological report of the specimen was an abscess caused by N. cyriacigeorgica. The patient received appropriate antibiotic treatment and completely recovered without sequelae. CONCLUSIONS: Nocardia species are a rare cause of brain abscess in immunocompetent patients. Their clinical presentation can mimic other more common cerebral diseases, such as brain tumors (primary and secondary) and stroke. The possibility of an abscess caused by N. cyriacigeorgica should also be considered in the differential diagnosis in an immunocompetent patient.