Surgical treatment of pontine cavernous malformations (CMs) is challenging due to the anatomical difficulties and potential risks involved. We successfully applied an anterior transpetrosal approach (ATPA) to remove a lower ventral pontine CM, and herein we discuss the outline of our procedure accompanied by a surgical video.A 50-year-old woman presenting with progressively worsening diplopia was urgently admitted to our hospital. Preoperative images showed a lower ventral pontine CM compressing the corticospinal tract posteriorly. Considering the location of the CM, we determined that an ATPA was the appropriate approach to achieve a more anterolateral trajectory. We performed extradural anteromedial petrosectomy and penetrated the brainstem from the point just below the anterior inferior cerebellar artery and above the root exit zone of the abducens nerve, which might be located in the somewhat lowest border of actual maneuverability in the ATPA. Maneuverability through this corridor was sufficient without hindering and darkening the high magnification microscopic view, as demonstrated in our surgical video.This report demonstrates surgical treatment of a lower ventral pontine CM using the ATPA. The surgical video we present provides information that is useful for understanding this technique's maneuverability and working window.
Operative management of clinoidal meningiomas remains challenging. Several techniques to safely treat this tumor have been reported. Damage to the surrounding structures, such as major vessels, could be fatal; therefore, it is preferable to avoid total resection for the patient's safety. Thus, subtotal resection with gamma knife radiosurgery (GKRS) is an alternative method. It is crucial to remove the tumor around the optic nerve, relieve the nerve from tumor compression, and maintain good tumor control after GKRS. This report proposes an adjunctive operative management technique for clinoidal meningioma. The patient was a 62-year-old-woman with a right clinoidal meningioma who was referred to our department. Magnetic resonance imaging (MRI) revealed a mass lesion in the middle cranial fossa, with infiltration and compression of surrounding structures. Therefore, we planned a subtotal resection with superficial temporal artery-middle cerebral artery (STA-MCA) bypass and additional GKRS. Considering operative complications and postoperative GKRS, anterior clinoidectomy, optic canal unroofing, and aggressive resection around the optic nerves were similarly planned. The operation was performed safely, and the bypassed artery worked as long-term insurance for ischemic complications. We planned a subtotal resection followed by GKRS to prevent major operative complications. In our case, we additionally adopted three specific measures to ensure the safety of the procedure. Notably, STA-MCA bypass was also beneficial as long-term management, as it serves a supportive role for providing collateral flow in cases of vascular stenosis that the patient may experience in the future.
Adult patients with moyamoya disease (MMD) may present with mild cognitive dysfunction, even those without evidence of conspicuous brain parenchymal damage. This cognitive dysfunction might be caused by local frontal lobe ischemia.To explore the relationship between frontal lobe hemodynamic insufficiency and cognitive dysfunction in patients with MMD.Thirty adult patients with MMD without conspicuous brain parenchymal damage were retrospectively examined. Patients with MMD with frontal lobe intracerebral steal phenomenon on single photon emission computed tomography were defined as group S (n = 13) and those without it were defined as group P (n = 17). A comparative group comprising patients with unruptured intracranial aneurysm was defined as group C (n = 30). The results of various cognitive and intelligence tests and a composite cognitive score were compared between groups.The digit span test forward version ( P = .041), frontal assessment battery ( P = .022), and composite cognitive score ( P = .015) z-scores were significantly lower in group S than group C. Adjusting for sex and age, patients in group S had a significantly lower composite cognitive score compared with those in group C in multiple regression analysis ( P = .037). Executive dysfunction and working memory dysfunction may be involved in the cognitive decline observed in group S.Mild cognitive dysfunction in MMD was associated with frontal lobe hemodynamic insufficiency. Future studies should examine whether revascularization can improve cerebral hypoperfusion and neurocognitive function in these patients.
Abstract Introduction: Large cystic brain metastases are relatively rare and are not good candidates for stereotactic radiosurgery. Stereotactic aspiration followed by Gamma Knife radiosurgery (GKRS) is a reasonable and effective management strategy. However, even with aspiration, the target lesion tends to exceed the dimensions of an ideal target for stereotactic radiosurgery. This study aimed to investigate the effectiveness of frameless fractionated GKRS (f-GKRS) for large cystic brain metastases with cyst aspiration using Ommaya reservoir implantation. Methods: Between May 2018 and April 2021, eight consecutive patients with nine lesions were treated with f-GKRS in five or ten sessions after cyst aspiration. The aspiration was repeated as needed throughout the treatment course to maintain the cyst size and shape. The patient characteristics, radiologic tumor response, and clinical course were reviewed using medical records. The mean follow-up duration was 10.2 months (2–28 months). Results: The mean pre-GKRS volume and maximum diameter were 16.7 mL (5–55.8 mL) and 39.0 mm (31–79 mm), respectively, and the mean tumor volume reduction achieved by aspiration was 55.4%. The tumor volume decreased for all lesions, and symptoms were alleviated in all patients. The median overall survival was 10.0 months, and the estimated one-year survival rate was 41.7% (95% CI: 10.9–70.8%). The local tumor control rate was 100%. No irradiation-related adverse events were observed. Conclusions: Ommaya reservoir implantation and aspiration followed by frameless f-GKRS is a less invasive, effective, and safe method, and should be considered as a management option for large cystic brain metastases.
Antiangiogenic vascular endothelial growth factor receptor tyrosine kinase inhibitors play an essential role in systemic therapy for renal cell carcinoma. Given the anti-edematous effect of bevacizumab, an antiangiogenic antibody targeting vascular endothelial growth factor, vascular endothelial growth factor receptor tyrosine kinase inhibitors should exert therapeutic effects on radiation-induced brain injury after stereotactic radiosurgery. This preliminary study aimed to investigate the therapeutic effect of vascular endothelial growth factor receptor tyrosine kinase inhibitor against radiation-induced brain injury.Magnetic resonance images for six patients treated with vascular endothelial growth factor receptor tyrosine kinase inhibitors who were diagnosed with radiation-induced brain injury following gamma knife radiosurgery were retrospectively reviewed.The median brain edema volume and tumour mass volume in the pre-tyrosine kinase inhibitor period were 57.6 mL (range: 39.4-188.2) and 3.2 mL (range: 1.0-4.6), respectively. Axitinib, pazopanib (followed by cabozantinib) and sunitinib were administered in four, one and one cases, respectively. The median brain edema volume and tumour mass volume in the post-tyrosine kinase inhibitor period were 4.8 mL (range: 1.5-27.8) and 1.6 mL (range: 0.4-3.6), respectively. The median rates of reduction in brain edema volume and tumour mass volume were 90.8% (range: 51.9-97.6%) and 57.2% (range: 20.0-68.6%), respectively. The post-tyrosine kinase inhibitor values for brain edema volume (P = 0.027) and tumour mass volume (P = 0.008) were significantly lower than the pre-tyrosine kinase inhibitor values. Changes in volume were correlated with tyrosine kinase inhibitor use.This study is the first to demonstrate the therapeutic effects of vascular endothelial growth factor receptor tyrosine kinase inhibitors on radiation-induced brain injury in patients with brain metastases from renal cell carcinoma treated via gamma knife radiosurgery.
