Publications by authors named "Alex P Michael"

Background: The use of 5-aminolevulinic acid (5-ALA) for intraoperative protoporphyrin IX fluorescent imaging in the resection of malignant gliomas has been demonstrated to improve tumor visualization, increase the extent of resection, and extend progression-free survival. The current technique for visualization of 5-ALA consists of excitation and emission filters built into the operating microscope. However, there are notable limitations to this process, including low quantum yield, expense, and masking of surrounding anatomy.

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Objective: Spontaneous CSF leaks into the anterior skull base nasal sinuses are often associated with meningoencephaloceles and occur in patients with idiopathic intracranial hypertension (IIH). Endonasal endoscopic repair has become the primary method of choice for repair. The authors sought to evaluate the success rate of endoscopic closure and to identify predictive factors for CSF leak recurrence.

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Background: Neurosurgeons are frequently consulted for traumatic brain injuries (TBIs) resulting in intracranial hemorrhage (ICH). After inpatient confirmation of hemorrhage stability, outpatient head computed tomography (CT) is often performed to assess for hemorrhage resolution. Our objective was to assess the practice patterns and clinical utility of routine outpatient head CT scans for patients with mild TBI (mTBI).

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Objective: Intracranial hemorrhage (ICH) is frequently found on computed tomography (CT) after mild traumatic brain injury (mTBI) prompting transfer to centers with neurosurgical coverage and repeat imaging to confirm hemorrhage stability. Studies suggest routine repeat imaging has little utility in patients with minimal ICH, no anticoagulant/antiplatelet use, and no neurological decline. Additionally, it is unclear which mTBI patients benefit from transfer for neurosurgery consultation.

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Introduction: Radiodynamic therapy (RDT) involves administration of a radiosensitizing agent and its subsequent activation by ionizing radiation for destruction of neoplastic cells.

Materials And Methods: A comprehensive evaluation of the literature was performed to review the history of RDT using porphyrins for solid tumors, the cellular mechanisms of action, immunomodulatory effects, and both preclinical and clinical studies for use in high-grade gliomas (HGGs). This manuscript was prepared in accordance with the PRISMA guidelines.

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Robotic surgery has become more common in otolaryngologic surgery since the introduction of the da Vinci robotic system, but has played a limited role in anterior and central skull base surgery, largely because of technical limitations of existing robots. Current robotic technology has been used in creative ways to access the skull base, but was not designed to navigate these complex anatomic constraints. Novel robots should target many of the limitations of current robotic technology, such as maneuverability, inability to suture, lack of haptic feedback, and absent integration with image guidance.

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Prognosis for diffuse intrinsic pontine glioma (DIPG) and generally for diffuse midline gliomas (DMG) has only marginally improved over the last ~40 years despite dozens of chemotherapy and other therapeutic trials. The prognosis remains invariably fatal. We present here the rationale for a planned study of adding 5-aminolevulinic acid (5-ALA) to the current irradiation of DIPG or DMG: the 5aai regimen.

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Background: Synovial cysts are most commonly found in the lumbar spine and are associated with low back pain and radiculopathy. Frequent use of imaging modalities has led to an increase in intraspinal synovial cyst identification. Treatment typically ranges from conservative measures to surgical decompression, but spontaneous resolution has previously been reported.

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Objective: While long-term studies have evaluated adjacent-segment disease (ASD) following posterior lumbar spine arthrodesis, no such studies have assessed the incidence and prevalence of ASD following axial lumbar interbody fusion (AxiaLIF). The aim of this study was to estimate the incidence of ASD following AxiaLIF.

Methods: The authors retrospectively reviewed the medical records of 149 patients who underwent two-level index AxiaLIF and had at least 2 years of radiographic and clinical follow-up.

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Purpose: Fluorescence-guided surgery (FGS) with the use of 5-aminolevulinic acid (5-ALA) leads to more extensive resection of high-grade glioma (HGG) and longer overall survival (OS) of patients compared to conventional resection. The purpose of this study is to investigate the effect of 5-ALA dosages on residual tumor volume (RTV) and OS in patients with glioblastoma.

Methods: A retrospective cohort study for patients who participated in a phase I and II dose-escalation clinical trial on 5-ALA for resection of HGG.

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Background: The utility of oral 5-aminolevulinic acid (5-ALA)/protoporphyrin fluorescence for the resection of high-grade gliomas is well documented. This drug has received regulatory approval in Europe but awaits approval in the United States.

Objective: To identify the appropriate dose and toxicity or harms of 5-ALA used for enhanced intraoperative visualization of malignant brain tumors, reported from a single medical center in the United States.

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Decompressive craniectomy is reserved for extreme cases of intracranial hypertension. An uncommon complication known as paradoxical herniation has been documented within weeks to months following surgery. Here we present a unique case within days of surgery.

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Military service members frequently sustain traumatic brain injuries (TBI) while on active duty, a majority of which are related to explosive blasts and are mild in severity. Studies evaluating the cortical gray matter in persons with injuries of this nature remain scarce. The purpose of this study was to assess cortical thickness in a sample of military veterans with chronic blast-related TBI.

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Although once a widely speculated about and largely theoretical topic, spaceflight-induced intracranial hypertension has gained acceptance as a distinct clinical phenomenon, yet the underlying physiological mechanisms are still poorly understood. In the past, many terms were used to describe the symptoms of malaise, nausea, vomiting, and vertigo, though longer duration spaceflights have increased the prevalence of overlapping symptoms of headache and visual disturbance. Spaceflight-induced visual pathology is thought to be a manifestation of increased intracranial pressure (ICP) because of its similar presentation to cases of known intracranial hypertension on Earth as well as the documentation of increased ICP by lumbar puncture in symptomatic astronauts upon return to gravity.

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