Marcos Vinicius Calfat Maldaun

Stereotactic radiosurgery for metastatic brain tumors: a comprehensive review of complications: Clinical article

OBJECT Stereotactic radiosurgery (SRS) is commonly used to treat brain metastases. Complications associated with this treatment are underreported. The authors reviewed a large series of patients who underwent SRS for brain metastases to identify complications and factors predicting their occurrence. METHODS Prospectively collected clinical data from 273 patients undergoing SRS for 1 or 2 brain metastases at The University of Texas M. D. Anderson Cancer Center between June 1993 and December 2004 were reviewed. Patients who had received prior treatment for their tumor, including whole-brain radiation, SRS, or surgery, were excluded from the study. Data on adverse neurological and nonneurological outcomes following treatment were collected. RESULTS Three hundred sixteen lesions were treated. Complications were associated with 127 (40%) of 316 treated lesions. New neurological complications were associated with 101 (32%) of 316 lesions. The onset of seizure was the most common complication, occurring in 41 (13%) of 316 SRS cases. On multivariate analysis, progressing primary cancer (hazard ratio [HR]=2.4, 95% CI 1.6-3.6, p<0.001), tumor location in eloquent cortex (HR=2.3, 95% CI 1.6-3.4, p<0.001), and lower (<15 Gy) SRS dose (HR=2.1, 95% CI 1.1-4.2, p=0.04) were significantly associated with new complications. On multivariate analysis, a tumor location in the eloquent cortex (HR=2.5, 95% CI 1.6-3.8, p<0.001) and progressing primary cancer (HR=1.6, 95% CI 1.1-2.5, p=0.03) were significantly associated with new neurological complications. CONCLUSIONS The authors showed that new neurological and nonneurological complications were associated with 40% of SRS treatments for brain metastases. Patients with lesions in functional brain regions have a significantly increased risk of treatment-related complications.

Positive and negative prognostic variables for patients undergoing spine surgery for metastatic breast disease.

The histology of the primary tumor in metastatic spine disease plays an important role in its treatment and prognosis. However, there is paucity in the literature of histology-specific analysis of spinal metastases. In this study, prognostic variables were reviewed for patients who underwent surgery for breast metastases to the spinal column. Respective chart review was done to first identify all patients with breast cancer over an 8-year period at a major cancer center and then to select all those with symptomatic metastatic disease to the spine who underwent spinal surgery. Univariate and multivariate analyses were used to assess several prognostic variables. Presence of visceral metastases, multiplicity of bony lesions, presence of estrogen receptors (ER), and segment of spine (cervical, thoracic, lumbar, sacral) in which metastases arose were compared with patient survival. Eighty-seven patients underwent 125 spinal surgeries. Those with estrogen receptor (ER) positivity had a longer median survival after surgery compared to those with estrogen receptor negativity. Patients with cervical location of metastasis had a shorter median survival compared with those having metastases in other areas of the spine. The presence of visceral metastases or a multiplicity of bony lesions did not have prognostic value. In patients with spinal metastases from breast cancer, aggressive surgical management may be an option for providing significant pain relief and preservation/improvement of neurological function. Interestingly, in patients undergoing such surgery, cervical location of metastasis is a negative prognostic variable, and ER-positivity is associated with better survival, while presence of visceral or multiple bony lesions does not significantly alter survival.

Petroclival meningiomas: Surgical management and common complications

Petroclival meningiomas are technically challenging lesions. They have a tendency to grow slowly, involve cranial nerves and compress the brainstem and basilar artery, pushing them to the opposite side. Their natural history is marked by clinical deterioration and fatal outcome. They were once considered inoperable lesions; decades ago, mortality rates were higher than 50%. The authors describe 15 petroclival meningiomas treated surgically between 1995 and 2007. The main approaches used were combined anterior petrosectomy and retrosigmoid (3 cases), retrosigmoid (8 cases), and pre-sigmoid and subtemporal (4 cases). The mortality rate was 13.5% due to surgical bed hematoma and brain ischemia. The post-operative complications were hydrocephalus in 2 cases, cerebrospinal fluid leak in 2 cases and infection of surgical flap in one case. Limiting factors for surgical removal are tumor consistency, encasement of brainstem perforators and pre-operative clinical status.

Awake craniotomy for gliomas in a high-field intraoperative magnetic resonance imaging suite: analysis of 42 cases

OBJECTIVES The object of this study was to describe the experience of combining awake craniotomy techniques with high-field (1.5 T) intraoperative MRI (iMRI) for tumors adjacent to eloquent cortex. METHODS From a prospective database the authors obtained and evaluated the records of all patients who had undergone awake craniotomy procedures with cortical and subcortical mapping in the iMRI suite. The integration of these two modalities was assessed with respect to safety, operative times, workflow, extent of resection (EOR), and neurological outcome. RESULTS Between February 2010 and December 2011, 42 awake craniotomy procedures using iMRI were performed in 41 patients for the removal of intraaxial tumors. There were 31 left-sided and 11 right-sided tumors. In half of the cases (21 [50%] of 42), the patient was kept awake for both motor and speech mapping. The mean duration of surgery overall was 7.3 hours (range 4.0-13.9 hours). The median EOR overall was 90%, and gross-total resection (EOR ≥ 95%) was achieved in 17 cases (40.5%). After viewing the first MR images after initial resection, further resection was performed in 17 cases (40.5%); the mean EOR in these cases increased from 56% to 67% after further resection. No deficits were observed preoperatively in 33 cases (78.5%), and worsening neurological deficits were noted immediately after surgery in 11 cases (26.2%). At 1 month after surgery, however, worsened neurological function was observed in only 1 case (2.3%). CONCLUSIONS There was a learning curve with regard to patient positioning and setup times, although it did not adversely affect patient outcomes. Awake craniotomy can be safely performed in a high-field (1.5 T) iMRI suite to maximize tumor resection in eloquent brain areas with an acceptable morbidity profile at 1 month.

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 Brocas area, 93 and 18% in Wernickes 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.

Giant pseudoaneurysm originated from distal middle cerebral artery dissection treated by trapping under sensitive evoked potential and motor evoked potential monitoring: Case report and discussion.

Background: Dissecting giant pseudoaneurysm of the middle cerebral artery (MCA) is a rare lesion often presenting challenges to neurosurgical teams dealing with this specific pathology. Giant pseudoaneurysm originating from a dissecting distal segment of the MCA treated with aneurysm trapping under motor and sensitive evoked potential monitoring with a successful outcome is presented in the article followed by a brief discussion on the subject. Case Description: A case of a previously healthy young female patient admitted at the emergency room of Santa Paula Hospital with a history of a sudden headache and syncope, dysphasia, and Grade 4 right hemiparesis due to a large brain hemorrhage secondary to a 25 mm ruptured pseudoaneurysm originated from a distal left MCA dissecting segment is described. Because the patient risked neurological worsening, aneurysm was treated with parent and efferent vessel trapping technique and no changes on the sensitive and motor evoked potential (MEP) from baseline informed on this decision. Hemorrhage was completely drained after aneurysm was secured. Conclusion: Neurophysiological sensitive and MEP monitoring, on this specific case was a valuable tool and informed on the decision of trapping of this large vascular lesion.

Cerebellar Liponeurocytoma: A Literature Review and Case Report

Cerebellar liponeurocytoma is an extremely rare cerebellar neoplasm of adults, which is characterized by astrocytic and lipomatous differentiation, with a low proliferative potential. Until now, there are only 31 reports of cerebellar liponeurocytoma. Neurosurgeons are not familiarized with this entity. It is not a part of the tumor repertoire that is dealt with in daily practice. Despite its rarity, it is mandatory to distinguish it from medulloblastomas. Cerebellar liponeurocytoma usually has a more favorable prognosis and does not require chemotherapy or radiotherapy. In this study, we describe a 62-year-old woman harboring cerebellar liponeurocytoma, and briefly review the existing literature.

Minimally Invasive Interhemispheric Approach for Giant Olfactory Groove Meningioma: Technical Note

BACKGROUND Skull base tumors, such as large olfactory groove meningiomas (OGMs), are a challenge for neurosurgeons. However, the tendency to reduce invasive surgeries is gaining more adepts. We describe a minimally invasive interhemispheric approach with a falx window for microsurgical resection of the giant OGM as a technical note. METHODS A minimal medial frontal craniotomy measuring 3-5 cm in size is performed, and an interhemispheric approach is combined with an opening in the falx to improve microsurgical resection of the giant OGM. The technique and more details are described. RESULTS A minimally invasive interhemispheric approach with a falx window was performed in this case. Gross total resection of the OGM was possible with minimal brain retraction. Simpson grade I was achieved, and there was a good outcome on the postoperative recovery period of the patient, with vision improvement, preservation of olfaction, and no other complications. CONCLUSIONS The minimally invasive interhemispheric approach with a falx window is effective and safe for giant OGM with a good outcome for the patient. The opening in the falx improves the interhemispheric pathway and allows gross total resection with minimal brain retraction and low morbidity.

Cavernous Malformation of the Central Nervous System: Case Series Report and Review of Literature

Cavernous malformations are cerebrovascular anomalies that may be observed throughout the central nervous system, mainly in the supratentorial location, comprising about 10% of all cerebrovascular lesions. They frequently affect young patients, and may be observed as sporadic form or familial (hereditary) form. They may appear as single or multiple lesions. Most patients who present with the multiple lesions are likely to harbor the hereditary form of the disease. Magnetic resonance imaging is the standard imaging to diagnose the cavernous malformation, as they are angiographically occult. An autosomal-dominant pattern of inheritance with variable penetrance is responsible to the familial form of the disease. There are 4 types of clinical presentation of the cavernous malformation: seizures, headaches, neurologic deficits, and asymptomatic presentation. The treatment consists of microscopic surgical resection assisted by intraoperative neuronavigation, stereotaxy, or ultrasound, with minimal morbidity. Radiosurgery may be considered for patient with multiple hemorrhages from a surgically inaccessible lesion, or in clinically ill patients without health for surgery. We report a series of 29 patients harboring supratentorial cavernous malformations surgically removed, operated from 1999 to 2009, at São Paulo, Brazil, by the same surgical crew, to verify surgery as the primary management strategy.