Supratentorial cerebrospinal fluid diversion using image-guided trigonal ventriculostomy during retrosigmoid craniotomy for cerebellopontine angle tumors.

Background: Cerebellar contusion, swelling and herniation is frequently encoutered upon durotomy in patients undergoing retrosigmoid craniotomy for cerebellopontine angle (CPA) tumors, despite using standard methods to obtain adequate cerebellar relaxation. Objective: The aim of this study is to report an alternative cerebrospinal fluid (CSF)-diversion method using image-guided ipsilateral trigonal ventriculostomy. Methods: Single-center retro- and prospective cohort study of n = 62 patients undergoing above-mentioned technique. Prior durotomy, CSF-diversion was performed to the point where the posterior fossa dura was visibly pulsatile. Outcome assessment consisted of the surgeon's intra- and postoperative clinical observations, and postoperative radiological imaging. Results: Fifty-two out of n = 62 (84%) cases were eligible for analysis. The surgeons consistently reported successful ventricular puncture and a pulsatile dura prior durotomy without cerebellar contusion, swelling or herniation through the dural incision in n = 51/52 (98%) cases. Forty-nine out of n = 52 (94%) catheters were placed correctly within the first attempt, with the majority of catheter tips (n = 50, 96%) located intraventricularly (grade 1 or 2). In n = 4/52 (8%) patients, postoperative imaging revealed evidence of a ventriculostomy-related hemorrhage (VRH) associated with an intracerebral hemorrhage [n = 2/52 (4%)] or an isolated intraventricular hemorrhage [n = 2/52 (4%)]. However, these hemorrhagic complications were not associated with neurological symptoms, surgical interventions or postoperative hydrocephalus. None of the evaluated patients demonstrated radiological signs of upward transtentorial herniation. Conclusion: The method described above efficiently allows CSF-diversion prior durotomy to reduce cerebellar pressure during retrosigmoid approach for CPA tumors. However, there is an inherent risk of subclinical supratentorial hemorrhagic complications.

Evolving Strategies for Resection of Sellar/Parasellar Synchronous Tumors via Endoscopic Endonasal Approach: A Technical Case Report and Systematic Review of the Literature.

BACKGROUND: Data on the endonasal endoscopic approach (EEA) to treat sellar/parasellar synchronous tumors remain sparse. This work aims to describe a minimally invasive approach with intraoperative magnetic resonance imaging (MRI) to remove a large sellar/parasellar synchronous tumor, and presents a systematic literature review. METHODS: The preoperative MRI of a 54-year-old woman revealed a sellar lesion (28 × 19 × 16 mm), presumably a pituitary macroadenoma, and a second extra-axial lesion (22 × 36 × 20 mm) expanding from the tuberculum sellae to the planum sphenoidale with encasement of the anterior communicating complex, presumably a meningioma. We used intraoperative MRI to assess the extent of the resection before reconstructing the large skull base defect. Furthermore, we systematically reviewed pertinent articles retrieved by a PubMed/Embase database search between 1961 and December 2018. RESULTS: Out of 63 patients with synchronous tumors reported in 43 publications, we found 3 patients in which the tumor was removed by EEA. In these 3 patients and the presented case, the resection of both lesions was successful, without major approach-related morbidity or mortality. More extensive removal of endonasal structures to gain an adequate tumor exposure was not necessary. We did not find any previous reports describing the benefits of intraoperative MRI in the presented setting. CONCLUSIONS: In the rare case of a synchronous meningioma and pituitary adenoma of the sellar region, intraoperative MRI might be beneficial in confirming residual disease before skull base reconstruction, and therefore radiologic follow-up.

Malignant Transformation of a Rosette-Forming Glioneuronal Tumor with IDH1 Mutation: A Case Report and Literature Review.

BACKGROUND: Rosette-forming glioneuronal tumor (World Health Organization grade I) is considered as a benign tumor with very low potential for progression. The potential for malignant transformation of this tumor is not known and has never been reported before in literature. CASE DESCRIPTION: We report a 42-year-old man, diagnosed with rosette-forming glioneuronal tumor of the fourth ventricle with a positive isocitrate dehydrogenase 1 mutation, progressed to glioblastoma after 6 years from diagnosis. We discuss the clinical history, radiological findings, and histopathological characteristic with immunohistochemistry findings observed in this unique case. CONCLUSIONS: Despite being acceptable as benign, based on our observations in this case, there is a potential for malignant transformation of rosette-forming glioneuronal tumor. The role of isocitrate dehydrogenase 1 mutation leading to malignant transformation could not be established as our finding is novel and further prospective studies are required to prove this association.

A rare case of perivascular epithelioid cell tumour metastases to the brain.

Perivascular epithelioid cell tumour is a rare mesenchymal tumour with distinct immunohistochemical profile. While it is known to occur in various anatomical sites, the central nervous system had always been a protected site for primary or secondary perivascular epithelioid cell tumours. We describe a 61-year-old lady who presented with symptoms of raised intracranial pressure, 3 months after the resection of duodenal and thoracic tumours which were histologically consistent with perivascular epithelioid cell tumour. She was investigated and then subsequently subjected to resection of two metastatic intracranial lesions. The radiological, intraoperative as well as histopathological findings of the metastatic lesions are discussed. Metastatic perivascular epithelioid cell tumour of the brain is extremely rare. However, patients who are stratified as high risk for recurrence or metastases should undergo an early magnetic resonance imaging/computed tomography of the brain in addition to a whole-body positron emission tomography scan, to allow for early detection and management of these tumours.

Single Port Endoscope-Assisted Excision of Forehead Lesions: An Innovative Way of Improving the Optical Cavity.

Exophytic lesions involving the face present with an undesirable esthetic deformity and usually necessitate surgical excision. Conventional open excision techniques may lead to scar formation or pigmentation issues postoperatively. Minimally invasive endoscope-assisted surgery will be able to overcome these problems. However, this technique is not widely used because of the limited optical cavity working space, which hinders good visualization. We describe a technique to improve the optical cavity workspace to enable adequate endoscope-assisted surgical excision of forehead lesions in 2 cases. Foley's catheter and ribbon gauze were used in both cases to gain optical cavity workspace. The surgical technique is described in detail. One case had a frontal osteoma, whereas other was a nodular fasciitis of the forehead, confirmed by histology. Postoperative follow-up showed good outcomes at 1 year with no recurrences. Both patients were satisfied with the surgical and cosmetic outcomes. Endoscopic excision of a forehead lesion using the described technique is both safe and reliable. It is an excellent method for excising benign growths over the forehead while being cosmetically acceptable.