Search

Introduction: The major mechanism of morbidity of delayed cerebral ischemia after subarachnoid hemorrhage (SAH) is considered to be severe vasospasm. Quantitative MRA (QMRA) provides direct measurements of vessel-specific volumetric blood flow and may permit a clinically relevant assessment of the risk of ischemia secondary to cerebral vasospasm. Purpose: To evaluate the utility of QMRA as an alternative imaging technique for the assessment of cerebral vasospasm after SAH. Methods: QMRA volumetric flow rates of the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA) were compared with vessel diameters on catheter-based angiography. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of QMRA for detecting cerebral vasospasm was determined by receiver-operating characteristic curves. Spearman correlation coefficients were calculated for QMRA flow versus angiographic vessel diameter. Results: Sixty-six vessels (10 patients) were evaluated with QMRA and catheter-based angiography. The median percent QMRA flow of all vessels with angiographic vasospasm (55.0%, IQR 34.3–71.6%) was significantly lower than the median percent QMRA flow of vessels without vasospasm (91.4%, IQR 81.4–100.4%) (p < 0.001). Angiographic vasospasm reduced QMRA-assessed flow by 23 ± 5 (p = 0.018), 95 ± 12 (p = 0.042), and 16 ± 4 mL/min (p = 0.153) in the ACA, MCA, and PCA, respectively, compared to vessels without angiographic vasospasm. The sensitivity, specificity, PPV, and NPV of QMRA for the discrimination of cerebral vasospasm was 84%, 72%, 84%, and 72%, respectively, for angiographic vasospasm >25% and 91%, 60%, 87%, and 69%, respectively, for angiographic vasospasm >50%. The Spearman correlation indicated a significant association between QMRA flows and vessel diameters (rs = 0.71, p < 0.001). Conclusion: Reduction in QMRA flow correlates with angiographic vessel narrowing and may be useful as a non-invasive imaging modality for the detection of cerebral vasospasm after SAH. [ABSTRACT FROM AUTHOR]

This article discusses the use of brainstem mapping in conjunction with the one-point method for the resection of brainstem cavernomas. Brainstem cavernomas are challenging due to their proximity to critical cranial nerve nuclei and tracts, as well as high re-hemorrhage rates. The study reviewed 36 patients who underwent resection using the one-point method and intraoperative brainstem mapping. The results showed that brainstem mapping reliably identified the location of relevant cranial nerve nuclei and modified the entrance to the lesion in most patients. The use of brainstem mapping, along with the one-point method, resulted in good functional outcomes and complete resection in the majority of patients. [Extracted from the article]

Introduction: Current methods for angioplasty and stenting of the intracranial vasculature for neurointervention are limited. The Wingspan Stent System is Food and Drug Administration (FDA) approved with human device exemption for a limited patient group and despite numerous prospective registries and trials demonstrating reasonable safety, still carries warnings from the FDA for its use. Given these limitations, we present the technical nuances and outcomes of the off-label use of the Resolute Onyx drug-eluting stent (DES) for neurointerventional purposes. Methods: Retrospective chart review of all patients undergoing a neurointerventional procedure with the Resolute Onyx DES was done from January 2017–2021. The Resolute Onyx is a coronary balloon-mounted drug-eluting (zotarolimus) single wire laser cut stent. Technical details and procedural outcomes were collected. Results: In total 40 patients had attempted placement of the Resolute Onyx DES with procedural success in 95% of patients. The most common vessel stented was the basilar artery, 30% (12/40). The most common indication was intracranial atherosclerotic disease in 62.5% (25/40) patients, followed by acute stroke in 17.5% (7/40) of patients. The technical and procedural outcomes were excellent with only one technical complication (2.5%). Conclusions: This series describes the initial technical safety and utility of utilizing a new generation balloon-mounted drug-eluting stent for neurointerventional purposes. This stent offers the potential for improved navigability, delivery, and outcomes compared to current neurointerventional options and warrants further study. [ABSTRACT FROM AUTHOR]

This article discusses the use of hologram-based craniectomy for the resection of an extensive en plaque meningioma compared to 3D-printed resection templates. The traditional method of cranial vault reconstruction after bone removal during skull base approaches is often suboptimal and costly. Patient-specific skull implants offer a solution, but precise preoperative determination of craniotomy dimensions and removed bone is necessary. The article presents a case study where hologram-based mixed reality resection was compared to template-guided resection, and the hologram was found to be accurate in patient positioning, incision planning, and craniectomy. The use of holograms can offer clearer positioning guidance compared to challenging-to-position templates and can assist in surgical planning, patient education, and more. [Extracted from the article]

This article discusses the use of stereotactic radiosurgery (SRS) as a treatment option for intracranial solitary fibrous tumors (SFTs). SFTs are rare tumors that are difficult to completely remove through surgery and have high recurrence rates. SRS, which delivers targeted radiation to the tumor, has shown promise in improving local tumor control without significant adverse effects. The study found that increasing the margin dose of SRS may lead to better tumor control. However, more research is needed to develop an optimal dosing strategy for SRS in the treatment of SFTs. [Extracted from the article]

This article compares the use of two different embolic agents, Onyx and n-BCA, for preoperative direct puncture embolization (DPE) of juvenile nasopharyngeal angiofibroma (JNA). The study found that both agents were effective in devascularizing JNA and facilitating safe resection with less intraoperative blood loss. However, there are important considerations for each technique, such as the special material properties, injection technique, cost, timing of injection, and consistency of the tumor post-injection. Surgeons should be aware of these differences to make informed decisions for patients with JNA. [Extracted from the article]

Disappearing intracranial aneurysms are rare and have not been extensively reported in the literature. They are often small or partially thrombosed and carry a significant risk of recurrence. We discuss a unique case of a 65-year-old woman who presented in 2006 with a subarachnoid hemorrhage and was found to have a ruptured posterior communicating artery and an unruptured P1 aneurysm. Follow-up angiography and imaging showed no changes in the size of a left P1 aneurysm for 11 years (2006–2017). However, in 2021, 15 years after initial presentation, no aneurysm was seen on magnetic resonance angiography, and subsequent digital subtraction angiography in 2022 showed almost complete disappearance of the unruptured P1 aneurysm. Literature review reveals only six reported cases during which a small, unruptured anterior circulation aneurysm disappeared, or regressed on follow-up imaging and no reported cases in the posterior circulation. [ABSTRACT FROM AUTHOR]

Background Surgical treatment of ventral and ventrolateral lesions of the craniocervical junction are among the most challenging neurosurgical pathologies to treat. Three surgical techniques, the far lateral approach (and its variations), the anterolateral approach, and the endoscopic far medial approach can be used to approach and resect lesions in this area. Objective The aim of the study is to examine the surgical anatomy of three skull base approaches to the craniocervical junction and review surgical cases to better understand the indications and possible complications for each of these approaches. Methods Cadaveric dissections with standard microsurgical and endoscopic instruments were performed for each of the three surgical approaches, and key steps and surgically relevant anatomy were documented. Six patients with appropriate pre-, post-, and intraoperative imaging and video documentation are presented and discussed accordingly. Results Based on our institutional experience, all three approaches can be utilized to safely and effectively approach a wide variety of neoplastic and vascular pathology. Unique anatomical characteristics, lesion morphology and size, and tumor biology should all be considered when determining the optimal approach. Conclusion Preoperative assessment of surgical corridors with 3D illustrations helps to define the best surgical corridor. 360 degree knowledge of the anatomy of craniovertebral junction allows safe surgical approach and treatment of ventral and ventrolateral located lesions using one of the three approaches. [ABSTRACT FROM AUTHOR]