Raphael P. Davis

Conservative management of acoustic neuroma : A meta-analysis and proposed treatment algorithm

Objectives/Hypotheses: Conservative management is a viable treatment alternative for acoustic neuroma. Using previous studies to provide evidence‐based support, we have attempted to more clearly define the role of conservative management.

A Model of Pulsations in Communicating Hydrocephalus

The traditional theory of communicating hydrocephalus has implicated the bulk flow component of CSF motion; that is, hydrocephalus is generally understood as an imbalance between CSF formation and absorption. The theory that the cause of communicating hydrocephalus is malabsorption of CSF at the arachnoid villi is not substantiated by experimental evidence or by physical reasoning. Flow-sensitive MRI has shown that nearly all CSF motion is pulsatile, and there is substantial evidence that hyperdynamic choroid plexus pulsations are necessary and sufficient for ventricular dilation in communicating hydrocephalus. We have developed a model of intracranial pulsations based on the analogy between the pulsatile motion of electrons in an electrical circuit and the pulsatile motion of blood and CSF in the cranium. Increased impedance to the flow of CSF pulsations in the subarachnoid space redistributes the flow of pulsations into the ventricular CSF and into the capillary and venous circulation. The salient features of communicating hydrocephalus, such as ventricular dilation, intracranial pressure waves, narrowing of the CSF-venous pressure gradient, diminished cerebral blood flow, elevated resistive index and malabsorption of CSF, emerge naturally from the model. We propose that communicating hydrocephalus is the result of a redistribution of CSF pulsations in the cranium.

Intracarotid chemotherapy with etoposide and cisplatin for malignant brain tumors

Chemotherapy for tumors of the central nervous system has a limited efficacy presumably because of restricted blood‐brain barrier permeability. The advantage of regional intra‐arterial administration of anticancer drugs is an increased uptake during the first passage of the drugs through tumor capillaries. Twenty patients with high‐grade astrocytomas (HGA) and 28 patients with metastatic brain tumors (MBT) received intracarotid/intravertebral infusion of etoposide and cisplatin. Eight patients with HGA who underwent incomplete resection responded to chemotherapy alone. Four additional patients had complete resection of the tumor. Median survival time of the group (responders and nonresponders) has been 14 months. Twelve patients with MBT responded to chemotherapy alone (six had complete response [CR], and six had partial response [PR]) with a median survival time of 7 months. Intra‐arterial chemotherapy (IAC) appears to be effective with acceptable toxicities. Accrual of additional patients is required before a final conclusion can be reached.

Paraganglioma of the cauda equina: Case report with magnetic resonance imaging description

The case of a 35-year-old white man with a cauda equina syndrome is presented. Magnetic resonance imaging confirmed the diagnosis, and radiation treatment successfully treated the condition.

Contemporary treatment with radiosurgery for spine metastasis and spinal cord compression in 2015

With the progress of image-guided localization, body immobilization system, and computerized delivery of intensity-modulated radiation delivery, it became possible to perform spine radiosurgery. The next question is how to translate the high technology treatment to the clinical application. Clinical trials have been performed to demonstrate the feasibility of spine radiosurgery and efficacy of the treatment in the setting of spine metastasis, leading to the randomized trials by a cooperative group. Radiosurgery has also demonstrated its efficacy to decompress the spinal cord compression in selected group of patients. The experience indicates that spine radiosurgery has a potential to change the clinical practice in the management of spine metastasis and spinal cord compression.

Minimally invasive evacuation of parenchymal and ventricular hemorrhage using the Apollo system with simultaneous neuronavigation, neuroendoscopy and active monitoring with cone beam CT

Introduction The Apollo system is a low profile irrigation–aspiration system which can be used for the evacuation of intracranial hemorrhage. We demonstrate the feasibility of using Apollo to evacuate intracranial hemorrhage in a series of three patients with combined neuronavigation, neuroendoscopy, and cone beam CT (CB-CT). Methods Access to the hematoma was planned using neuronavigation software. Parietal (n=2) or frontal (1) burr holes were created and a 19 F endoscopic sheath was placed under neuronavigation guidance into the distal aspect of the hematoma along its longest accessible axis. The 2.6 mm Apollo wand was then directed through the working channel of a neuroendoscope and used to aspirate the blood products under direct visualization, working from distal to proximal. After a pass through the hematoma, the sheath, neuroendoscope, and Apollo system were removed. CB-CT was then used to evaluate for residual hematoma. When required, the CB-CT data could then be directly uploaded into the neuronavigation system and a new trajectory planned to approach the residual hematoma. Results Three patients with parenchymal (n=2) and mixed parenchymal–intraventricular (n=1) hematomas underwent minimally invasive evacuation with the Apollo system. The isolated parenchymal hematomas measured 93.4 and 15.6 mL and were reduced to 11.2 (two passes) and 0.9 mL (single pass), respectively. The entire parenchymal component of the mixed hemorrhage was evacuated, as was the intraventricular component within the right frontal horn (single pass). No complications were experienced. All patients showed clinical improvement after the procedure. The average presenting National Institutes of Health Stroke Scale was 19.0, which had improved to 5.7 within an average of 4.7 days after the procedure. Conclusions The Apollo system can be used within the neuroangiography suite for the minimally invasive evacuation of intracranial hemorrhage using simultaneous neuronavigation for planning and intraprocedural guidance, direct visualization with neuroendoscopy, and real time monitoring of progress with CB-CT.

Rupture of a craniopharyngioma cyst following trauma: a case report

There have been only 20 reported cases of non-surgical rupture of a craniopharyngioma cyst, with only 3 cases secondary to trauma. Here we present a rare case of temporary shrinkage of a cystic craniopharyngioma following head trauma. After a motor vehicle accident in May 2001, a 61-year old woman began to have blurred vision and headaches. Magnetic resonance imaging (MRI) of the head revealed a primarily cystic mass measuring approximately two centimeters, involving the sellar and suprasellar area with compression of the pituitary. Visual field testing showed a left hemianopsia and the patient was referred for surgical evaluation. Transsphenoidal drainage of the cystic lesion in November 2001 provided histologic confirmation of the craniopharyngioma. Post-operative MRI showed cyst reduction and visual fields improved. Late in 2002, the patient again experienced progressive visual loss. Repeat MRI revealed a recurrent cystic craniopharyngioma, now measuring approximately three centimeters with subfrontal and parasellar extension and compression of the optic chiasm. A bifrontal surgical approach was advocated; however, prior to the scheduled surgery, the patient sustained a fall with trauma to the head. Following this event she experienced dramatic improvement in her headache and vision and repeat MRI showed the cystic lesion to be significantly decreased in size. Spontaneous rupture of craniopharyngioma cysts is uncommon but has been reported with increasing frequency. It is, however, exceedingly rare for a cyst to rupture following trauma.

Intraspinal psammomatous melanotic schwannoma not associated with Carney complex: case report

The authors present a case of intraspinal malignant psammomatous melanotic schwannoma (PMS) not associated with Carney complex and review all reported cases not associated with this syndrome. The focus of this review paper is on the characteristics of the malignant progression of PMS. A 54-year-old man had a history of squamous cell carcinoma of the neck and tonsillar carcinoma. The patients serial CT scanning study showed a mass in the left C-5 foramen. On presentation he was neurologically intact. After 18 months, the patient developed radiating pain down the left arm with decreased sensation. MRI of the cervical spine showed an enhancing 2.1 × 1.5 × 1.9-cm mass in the left C5-6 foramen. A C5-6 hemilaminectomy was performed with gross-total removal of the tumor. At 3 months postoperatively, the patient developed new-onset pain and weakness. MRI showed a dumbbell-shaped mass in the left C-7 foramen. MRI of the pelvis showed a 1.4 × 1.0-cm lesion on the right ischium and a 1.1 × 2.8-cm lesion on the right inferior pubic ramus. Anterior cervical discectomy of C5-6 and C6-7 with corpectomy of C-6 with subtotal resection of the tumor was completed. PMS should not be considered a benign tumor because in 41.1% of patients, including the patient in this report, the tumor progresses to malignancy. Long-term follow-up is needed in these patients. New surgical treatment plans should be considered.

Vascular Factors Affecting Drug Delivery to Brain Tumors

A satisfactory agent for boron neutron capture therapy (BNCT) must bind tumor cells in preference to normal cellular elements of the brain. However, it must also be delivered in sufficient concentration to the tumor cells by the bloodstream. The latter depends upon the degree of uptake or binding of the agent by blood cells or plasma proteins, the blood flow within the tumor, the permeability of the tumor vasculature to the particular boronated agent, and the distribution volumes of the agent within the tumor and adjacent brain tissue1,2.

Correction: First results on survival from a large Phase 3 clinical trial of an autologous dendritic cell vaccine in newly diagnosed glioblastoma [J Transl Med., 16, (2018) (142)] DOI: 10.1186/s12967-018-1507-6

Following publication of the original article [1], the authors reported an error in the spelling of one of the author names. In this Correction the incorrect and correct author names are indicated and the author name has been updated in the original publication. The authors also reported an error in the Methods section of the original article. In this Correction the incorrect and correct versions of the affected sentence are indicated. The original article has not been updated with regards to the error in the Methods section.