Retractorless interhemispheric transtentorial approach for large lesions in the posterior incisural space.

BACKGROUND: Surgical resection of lesions in the posterior incisural space presents a significant surgical challenge, which may result in postoperative visual complications and other neurological deficits. We, therefore, describe a retractorless interhemispheric transtentorial approach that avoids surrounding brain structures with positive outcomes and no complications or visual damage. CASE DESCRIPTION: We present four cases of lesions in the posterior incisural space that was treated with a retractorless interhemispheric transtentorial approach. Two patients were previously seen at another institution for a falcotentorial meningioma. We resected the meningiomas with a parietal-occipital interhemispheric transtentorial approach with no neurological deficits. A third patient presented with a large superior vermian hemangioblastoma with a steep angle of the tentorium. The fourth patient had a large upper vermian metastatic lesion with progressive enlargement, which was refractory to radiation treatments and chemotherapy, and we achieved partial resection. Postoperative visual function was completely preserved in all patients. CONCLUSION: A carefully executed retractorless interhemispheric approach in select cases is an effective option to reduce morbidity and prevent visual complications when removing lesions in the posterior tentorial incisure.

Houdini Tumor: Case Report and Literature Review of Pregnancy-Associated Meningioma.

BACKGROUND: Meningiomas are common intracranial neoplasms of undetermined etiology. Accelerated growth during episodes of elevated serum estrogen and progesterone have been demonstrated in pregnant patients, as exhibited by an overexpression of estrogen or progesterone on immunohistochemical analysis. This case report and literature review describe a case of complete meningioma regression in a postpartum patient. CASE DESCRIPTION: A 23-year-old female presented at 37 weeks of pregnancy with 1-month history of fluctuating severe left-sided headaches, periodic blurry vision, nausea, and vomiting. She had 2 previous pregnancies without complication. Magnetic resonance imaging revealed a dural-based, heterogeneously enhancing mass along the left tentorium, just posterior to the transverse sinus, with supratentorial extension and surrounding edema. Differential diagnoses included meningioma versus hemangioma versus hemangiopericytoma. The patient followed up with neurosurgery 1 month after delivery. She had continued left-sided headaches but no longer complained of visual changes. A postpartum surgical resection via left occipital and suboccipital craniotomy was planned. Approximately 1 month later (now about 3 months after delivery) a repeat magnetic resonance imaging demonstrated a marked decrease in meningioma size, and the previously seen edema had resolved. In light of the sudden disappearance of the meningioma, no further surgical intervention was pursued. CONCLUSIONS: Because meningioma shrinkage or disappearance may occur after pregnancy, repeat imaging is advised as part of a preoperative evaluation. In addition, it is possible that an undetermined amount of meningioma removal surgeries may be avoided with further research into monitoring hormone levels connected to meningioma growth.

Computed Tomography Cisternography for Evaluation of Trigeminal Neuralgia When Magnetic Resonance Imaging Is Contraindicated: Case Report and Review of the Literature.

BACKGROUND: Trigeminal neuralgia (TGN) causes severe unilateral facial pain. The etiology is hypothesized to be segmental demyelination of the trigeminal nerve root via compression by the superior cerebellar artery (SCA). Microvascular decompression (MVD) allows immediate and long-term pain relief. Preoperative evaluation includes magnetic resonance imaging (MRI) and/or magnetic resonance angiography of the brain. Having a pacemaker is a contraindication for MRI. There have been isolated reports of using computed tomography (CT) cisternography scans for radiation planning for TGN. CASE DESCRIPTION: A 75-year-old male with a permanent pacemaker who had refractory TGN in the V2 (maxillary) distribution of the trigeminal nerve underwent CT cisternography to prepare for MVD. CT angiography with Isovue 370 intravenous contrast injection and 0.625-mm axial images were obtained from the skull base across the posterior fossa. An intrathecal injection of Isovue 180 was performed at the L2/3 level. Imaging revealed the right SCA abutting the medial margin of the proximal right trigeminal nerve. In surgery (K.D.), a standard retrosigmoid suboccipital craniotomy was performed to access the cerebellopontine angle and separate the abutting SCA and trigeminal nerve. The patient had immediate pain relief. CONCLUSIONS: MRI is the preferred method of evaluating for TGN because it offers excellent visualization of vasculature in relation to the trigeminal nerve without accompanying radiation exposure. However, for patients who have contraindications to MRI, CT cisternography is shown to also be an effective method for visualizing the trigeminal root entry zone and nearby vasculature in preparation for MVD of the trigeminal nerve.

Minimal Clinically Important Difference for Safe and Simple Novel Acute Ischemic Stroke Therapies.

BACKGROUND AND PURPOSE: Determining the minimal clinically important difference (MCID) is essential for evaluating novel therapies. For acute ischemic stroke, expert surveys have yielded MCIDs that are substantially higher than the MCIDs observed in actual expert behavior in guideline writing and clinical practice, potentially because of anchoring bias. METHODS: We administered a structured, internet-based survey to a cross-section of academic stroke neurologists in the United States. Survey responses assessed demographic and clinical experience, and expert judgment of the MCID of the absolute increase needed in the proportion of patients achieving functional independence at 3 months to consider a novel, safe neuroprotective agent as clinically worthwhile. To mitigate anchoring bias, the survey response framework used a base 1000 rather than base 100 patient framework. RESULTS: Survey responses were received from 122 of 333 academic stroke neurologists, there were 23% women, 72.8% had ≥6 years of practice experience, and neurovascular disease accounted for more than half of practice time in >70%. Responder-nonresponder and continuum of resistance tests indicated that responders were representative of the full expert population. Among respondents, the median MCID was 1.3% (interquartile range, 0.8% to >2%). CONCLUSIONS: Stroke expert responses to MCID surveys are affected by anchoring and centrality bias. When survey design takes these into account, the expert-derived MCID for a safe acute ischemic stroke treatment is 1.1% to 1.5%, in accord with actual physician behavior in guideline writing and clinical practice. This revised MCID value can guide clinical trial design and grant-funding and regulatory agency decisions.

Lessons for the future: a review of sepsis past and present.

Sepsis continues to intrigue and challenge drug developers because of the high unmet need for this illness. The large market potential for sepsis is counterbalanced by the historical failure of multiple drug candidates for this indication that have not demonstrated clinical benefit. The failure of successful drug candidates can be attributed in part to a rudimentary under-standing of complex sepsis pathophysiology, unsophisticated and poor clinical trial design, and an over-reliance on preclinical models for proof-of-concept. Recent significant scientific advancements in these areas are expected to have a positive impact on sepsis drug development. This article reviews several treatment approaches for sepsis that are in clinical development to highlight the scope of research in this field. Although a near-term clinical breakthrough for sepsis is not imminent, current research provides a substantial amount of hope for the field.