Leptomeningeal carcinomatosis as primary manifestation of pancreatic cancer.

Leptomeningeal carcinomatosis (LMC) is a rare complication of cancer that often presents at an advanced stage after obvious metastasis of a primary cancer or locally advanced disease. We present an uncommon case of LMC secondary to pancreatic carcinoma presenting with headache, unilateral VII nerve palsy, and lower extremity weakness. Initial cerebrospinal fluid (CSF) studies were concerning for chronic aseptic meningitis but negative for malignant cells; the diagnosis of tuberculous meningitis was erroneously evoked. Three lumbar punctures were required to capture malignant cells. The diagnosis of LMC was based on CSF examination with cytology/immunohistochemistry and leptomeningeal enhancement on MRI. Post mortem autopsy revealed advanced and diffusely metastatic pancreatic adenocarcinoma. This patient demonstrates that solid tumors can present with leptomeningeal spread that often confuses the treating physician. Fungal or tuberculous meningitis can mimic LMC in the absence of neoplastic signs and negative CSF cytology. This event is exceedingly rare in pancreatic cancer. If the index of suspicion is high, repeat CSF sampling can increase the sensitivity of detection of malignant cells and thus result in the correct diagnosis.

Scarless abdominal fat graft harvest for neurosurgical procedures: technical note.

Background Abdominal fat grafts are often harvested for use in skull base reconstruction and cerebrospinal fluid (CSF) leak repairs, and for operations traversing the nasal sinuses or mastoid bone. Although the endoscopic transnasal surgery has gained significant popularity, in part because it is considered "scarless," a common adjunct, the abdominal fat graft, can result in a disfiguring scar across the abdomen. Objective This is the first report of a scarless abdominal fat graft technique for skull base reconstruction. Methods Ten patients with a median age of 56.5 years (range: 45-73 years) underwent endoscopic transsphenoidal tumor resection with intraumbilical fat graft harvest. Careful circumferential fat dissection at the umbilicus, with progressive retraction of the graft, was crucial to ensure maximal visualization and to prevent injury to the subcutaneous vessels and rectus fascia. Results Following reconstruction of the sellar skull base, all patients did well postoperatively with no evidence of CSF leak. At 12-week follow-up for all patients, there was no evidence of scar, intracavity hematoma, or wound infection. Conclusions Fat graft harvest through an intraumbilical incision results in a scar-free abdominal harvest, and is a useful procedural adjunct to complement "scarless" brain surgery.

Surgery for primary supratentorial brain tumors in the United States, 2000-2009: effect of provider and hospital caseload on complication rates.

OBJECT: The object of this study was to examine how procedural volume and patient demographics impact complication rates and value of care in those who underwent biopsy or craniotomy for supratentorial primary brain tumors. METHODS: The authors conducted a retrospective cohort study using data from the Nationwide Inpatient Sample (NIS) on 62,514 admissions for biopsy or resection of supratentorial primary brain tumors for the period from 2000 to 2009. The main outcome measures were in-hospital mortality, routine discharge proportion, length of hospital stay, and perioperative complications. Associations between these outcomes and hospital or surgeon case volumes were examined in logistic regression models stratified across patient characteristics to control for presentation of disease and comorbid risk factors. The authors further computed value of care, defined as the ratio of functional outcome to hospital charges. RESULTS: High-case-volume surgeons and hospitals had superior outcomes. After adjusting for patient characteristics, high-volume surgeon correlated with reduced complication rates (OR 0.91, p=0.04) and lower in-hospital mortality (OR 0.43, p<0.0001). High-volume hospitals were associated with reduced in-hospital mortality (OR 0.76, p=0.003), higher routine discharge proportion (OR 1.29, p<0.0001), and lower complication rates (OR 0.93, p=0.04). Patients treated by high-volume surgeons were less likely to experience postoperative hematoma, hydrocephalus, or wound complications. Patients treated at high-volume hospitals were less likely to experience mechanical ventilation, pulmonary complications, or infectious complications. Worse outcomes tended to occur in African American and Hispanic patients and in those without private insurance, and these demographic groups tended to underutilize high-volume providers. CONCLUSIONS: A high-volume status for hospitals and surgeons correlates with superior value of care, as well as reduced in-hospital mortality and complications. These findings suggest that regionalization of care may enhance patient outcomes and improve value of care for patients with primary supratentorial brain tumors.

Impact of preoperative functional magnetic resonance imaging during awake craniotomy procedures for intraoperative guidance and complication avoidance.

BACKGROUND: We wanted to study the role of functional MRI (fMRI) in preventing neurological injury in awake craniotomy patients as this has not been previously studied. OBJECTIVES: To examine the role of fMRI as an intraoperative adjunct during awake craniotomy procedures. METHODS: Preoperative fMRI was carried out routinely in 214 patients undergoing awake craniotomy with direct cortical stimulation (DCS). RESULTS: In 40% of our cases (n = 85) fMRI was utilized for the intraoperative localization of the eloquent cortex. In the other 129 cases significant noise distortion, poor task performance and nonspecific BOLD activation precluded the surgeon from using the fMRI data. Compared with DCS, fMRI had a sensitivity and specificity, respectively, of 91 and 64% in Broca's area, 93 and 18% in Wernicke's area and 100 and 100% in motor areas. A new intraoperative neurological deficit during subcortical dissection was predictive of a worsened deficit following surgery (p < 0.001). The use of fMRI for intraoperative localization was, however, not significant in preventing worsened neurological deficits, both in the immediate postoperative period (p = 1.00) and at the 3-month follow-up (p = 0.42). CONCLUSIONS: The routine use of fMRI was not useful in identifying language sites as performed and, more importantly, practiced tasks failed to prevent neurological deficits following awake craniotomy procedures.

A prospective randomized trial of perioperative seizure prophylaxis in patients with intraparenchymal brain tumors.

OBJECT: Seizures are a potentially devastating complication of resection of brain tumors. Consequently, many neurosurgeons administer prophylactic antiepileptic drugs (AEDs) in the perioperative period. However, it is currently unclear whether perioperative AEDs should be routinely administered to patients with brain tumors who have never had a seizure. Therefore, the authors conducted a prospective, randomized trial examining the use of phenytoin for postoperative seizure prophylaxis in patients undergoing resection for supratentorial brain metastases or gliomas. METHODS: Patients with brain tumors (metastases or gliomas) who did not have seizures and who were undergoing craniotomy for tumor resection were randomized to receive either phenytoin for 7 days after tumor resection (prophylaxis group) or no seizure prophylaxis (observation group). Phenytoin levels were monitored daily. Primary outcomes were seizures and adverse events. Using an estimated seizure incidence of 30% in the observation arm and 10% in the prophylaxis arm, a Type I error of 0.05 and a Type II error of 0.20, a target accrual of 142 patients (71 per arm) was planned. RESULTS: The trial was closed before completion of accrual because Bayesian predictive probability analyses performed by an independent data monitoring committee indicated a probability of 0.003 that at the end of the study prophylaxis would prove superior to observation and a probability of 0.997 that there would be insufficient evidence at the end of the trial to choose either arm as superior. At the time of trial closure, 123 patients (77 metastases and 46 gliomas) were randomized, with 62 receiving 7-day phenytoin (prophylaxis group) and 61 receiving no prophylaxis (observation group). The incidence of all seizures was 18% in the observation group and 24% in the prophylaxis group (p = 0.51). Importantly, the incidence of early seizures (< 30 days after surgery) was 8% in the observation group compared with 10% in the prophylaxis group (p = 1.0). Likewise, the incidence of clinically significant early seizures was 3% in the observation group and 2% in the prophylaxis group (p = 0.62). The prophylaxis group experienced significantly more adverse events (18% vs 0%, p < 0.01). Therapeutic phenytoin levels were maintained in 80% of patients. CONCLUSIONS: The incidence of seizures after surgery for brain tumors is low (8% [95% CI 3%-18%]) even without prophylactic AEDs, and the incidence of clinically significant seizures is even lower (3%). In contrast, routine phenytoin administration is associated with significant drug-related morbidity. Although the lower-than-anticipated incidence of seizures in the control group significantly limited the power of the study, the low baseline rate of perioperative seizures in patients with brain tumors raises concerns about the routine use of prophylactic phenytoin in this patient population.

Radiotherapy for recurrent epidermoid cyst.

Intracranial epidermoid cysts are rare benign congenital lesions for which the mainstay of treatment has been surgical resection. Due to a propensity to grow along the skull base, subtotal resection is often elected to avoid excessive surgical morbidity, but it comes with an increased risk of recurrence with its associated treatment difficulties. We here present the cases of three patients with recurrent epidermoid cyst who underwent multiple surgical resections followed by external beam radiation therapy with excellent results to date.

Revision to an adjustable non-siphon control valve in low pressure hydrocephalus: therapeutic siphoning and a new perspective on NPH: series of 3 cases and review of the literature.

INTRODUCTION: High intracranial compliance states requiring negative pressure drainage, otherwise known as low-pressure hydrocephalus syndromes, are rare conditions. The use of siphoning, enabled by revision to an adjustable shunt without an anti-siphon device, has been largely unexplored in low-pressure hydrocephalus. METHODS: Three patients with presumed normal pressure hydrocephalus (NPH) presented with unresolved symptoms, including urinary incontinence, disturbed gait, and cognitive dysfunction. Each was inadequately treated despite confirmed functioning Strata II valves (with built-in siphon control device) calibrated to the lowest pressure setting for maximum drainage. Surgical revision to Strata non-siphon control (NSC) valves was performed to allow for additional drainage via siphoning. RESULTS: Following revision to a shunt with a "siphoning" device, each patient achieved improved neurological function. Each differential pressure valve was initially set to a higher setting than with the Strata II valve. One of our patients experienced the formation of a subdural hematoma after shunt revision; resolution following adjustment of the valve to a higher setting suggests that siphoning may be of less importance to overdrainage syndromes when compared with valve opening pressure. CONCLUSION: Our findings indicate that intermittent intracranial hypotension achieved by siphoning is effective in the treatment of a subset of patients presenting clinically with NPH. Direct conversion to a shunt system without an anti-siphon device allows reduction of ventricular size without the risk associated with external ventricular drainage (EVD). With conversion to the Strata NSC valve, our patients had sustained clinical improvement, even at higher valve settings.

Subcortical injury is an independent predictor of worsening neurological deficits following awake craniotomy procedures.

BACKGROUND: Tailored craniotomies for awake procedures limit cortical exposure. Recently we demonstrated that the identification of eloquent areas increased the risk of postoperative deficits. However, it was not clear whether the observed neurological deficits were caused by proximity of functional cortex to the tumor [cortical injury] or subcortical injury. OBJECTIVE: We hypothesize that subcortical injury during tumor resection is an important predictor of postoperative neurological deficits compared to cortical injury. METHODS: A retrospective review of 214 patients undergoing awake craniotomy was carried out in whom preoperative functional magnetic resonance imaging (fMRI) and cortical mapping (CM) were performed. A radiologist blinded to the clinical data reviewed and graded the postoperative changes on diffusion-weighted MR-imaging (DWI). RESULTS: Of the 40 cases who developed new intraoperative neurological deficit, 36 (90%) occurred during subcortical dissection, 3 (7.5%) during both subcortical and cortical dissection, and 1 (2.5%) during cortical dissection. Neurological dysfunction acquired during subcortical dissection was an independent predictor of postoperative deficits both in the immediate postoperative period (P < .001) and at the 3-month follow-up (P < .001). Significant DWI restriction in the subcortical white matter was predictive of neurological deficits both immediately and at 3 months, P = .011 and P < .001, respectively. New or worsening deficits were seen in 38% of patients; however, at 3 months 13% had a mild persistent neurological deficit. CONCLUSION: Subcortical injury with significant DWI changes result in postoperative neurological decline despite our efforts to preserve cortical areas of function. This underscores the importance of preserving subcortical fiber tracts during awake craniotomy procedures.

In situ free-floating craniectomy for traumatic cerebral decompression in an infant: A field hospital solution.

BACKGROUND: Despite refinements in neurotrauma care, the morbidity and mortality of severe traumatic brain injury (TBI) in pediatric patients remains high. We report a novel approach to the surgical management of increased intracranial pressure in severe TBI utilizing an in situ free-floating craniectomy technique, which was originally devised as a creative solution to the unique challenges in a Haitian field hospital following the 2010 earthquake. CASE DESCRIPTION: A 13-month-old Haitian boy presented to Project Medishare field hospital in Port-au-Prince with left hemiplegia, a bulging fontanelle, and increasing lethargy following a traumatic head injury 4 days prior. An urgent craniectomy was performed based on clinical grounds (no brain imaging was available). A standard trauma flap incision was made, followed by a hemicraniectomy and expansion duraplasty. A small hematoma was evacuated. Frontal, temporal, and parietal bone flaps were placed on the dura in approximation to their normal anatomical configuration, but not affixed, leaving space for further brain edema, and the scalp was closed. The child experienced favorable peri-operative and early postoperative results. CONCLUSION: In situ free-floating craniectomy, while devised as a creative solution to limited resources in a natural disaster zone, may offer advantages over more traditional techniques.

Surgical excision of filum terminale arteriovenous fistulae after lumbar fusion: Value of indocyanine green and theory on origins (a technical note and report of two cases).

BACKGROUND: Intradural filum terminale arteriovenous fistulas (AVFs) are uncommon. We report two cases of this rare entity in which we used indocyanine green (ICG) videoangiography to identify the fistulous connection of each lesion. CASE DESCRIPTION: Two male patients presented with unresolved lower extremity weakness and paresthesias following lumbar fusion surgery. In each case, angiography showed an AVF between the filum terminale artery (FTA), the distal segment of the anterior spinal artery (ASA), and an accompanying vein of the filum terminale. A magnetic resonance image (MRI) obtained before lumbar fusion was available in one of these cases and demonstrated evidence of the preexisting vascular malformation. Surgical obliteration of each fistulous connection was facilitated by the use of ICG videoangiography. This emerging technology was instrumental in pinpointing fistula anatomy and in choosing the exact segment of the filum for disconnection. CONCLUSION: Our findings indicate that intradural filum terminale AVFs may have a congenital origin and that ICG is a useful tool in their successful surgical management. As these cases demonstrate, spine surgeons should remain vigilant in evaluating patients based on their clinical symptomatology, even in the presence of obvious lumbar pathology.