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Raphael Guzman and M. Sean Grady

✓ A case of cerebellar hemangioblastoma with a coexistent arterial aneurysm on the feeding artery of the tumor is reported. The patient presented with an acute onset of headache, loss of consciousness, and left-sided hemiparesis due to a posterior fossa hemorrhage found adjacent to a hemangioblastoma. Four-vessel angiography revealed an aneurysm on the anterior inferior cerebellar artery (AICA), which was the main feeding vessel of the hemangioblastoma. Successful total excision of the hemangioblastoma and clipping of the AICA aneurysm achieved in a one-stage operation was demonstrated on postoperative angiography.

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Maria Kamenova, Davide Croci, Raphael Guzman, Luigi Mariani and Jehuda Soleman

OBJECTIVE

Ventriculoperitoneal (VP) shunt placement is a common procedure for the treatment of hydrocephalus following diverse neurosurgical conditions. Most of the patients present with other comorbidities and receive antiplatelet therapy, usually acetylsalicylic acid (ASA). Despite its clinical relevance, the perioperative management of these patients has not been sufficiently investigated. The aim of this study was to compare the peri- and postoperative bleeding complication rates associated with ASA intake in patients undergoing VP shunt placement.

METHODS

Of 172 consecutive patients undergoing VP shunt placement between June 2009 and December 2015, 40 (23.3%) patients were receiving low-dose ASA treatment. The primary outcome measure was bleeding events in ASA users versus nonusers, whereas secondary outcome measures were postoperative cardiovascular events, hematological findings, morbidity, and mortality. A subgroup analysis was conducted in patients who discontinued ASA treatment for < 7 days (n = 4, ASA Group 1) and for ≥ 7 days (n = 36, ASA Group 2).

RESULTS

No statistically significant difference for bleeding events was observed between ASA users and nonusers (p = 0.30). Cardiovascular complications, surgical morbidity, and mortality did not differ significantly between the groups either. Moreover, there was no association between ASA discontinuation regimens (< 7 days and ≥ 7 days) and hemorrhagic events.

CONCLUSIONS

Given the lack of guidelines regarding perioperative management of neurosurgical patients with antiplatelet therapy, these findings elucidate one issue, showing comparable bleeding rates in ASA users and nonusers undergoing VP shunt placement.

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Stanley Hoang, Omar Choudhri, Michael Edwards and Raphael Guzman

A vein of Galen malformation is a rare intracranial vascular lesion affecting the pediatric population. Its poor prognosis has been significantly improved with the development of endovascular embolization. In this paper the authors review the developmental mechanisms, clinical pathophysiology, and the available data on the management and outcome of the disease.

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Maria Licci, Raphael Guzman and Jehuda Soleman

OBJECTIVE

Comparing prenatal and postnatal surgical repair techniques for myelomeningocele (MMC), in utero fetal surgery has increasingly gained acceptance and is considered by many specialized centers the first choice of treatment. Despite its benefits, as demonstrated in the Management of Myelomeningocele Study (MOMS), including reduced need for CSF shunting in neonates and improved motor outcomes at 30 months, there is still an ongoing debate on fetal and maternal risks associated with the procedure. Prenatal open hysterotomy, fetoscopic MMC repair techniques, and subsequent delivery by cesarean section are associated with maternal complications. The aim of this systematic review is to assess the available literature on maternal and obstetric complication rates and perinatal maternal outcomes related to fetal MMC repair.

METHODS

The authors identified references for inclusion in this review by searching PubMed and MEDLINE, with restrictions to English language, case series, case reports, clinical trials, controlled clinical trials, meta-analyses, randomized controlled trials, reviews, and systematic reviews. The rate of maternal and obstetric complications was analyzed based on studies focusing on this issue and presenting clear results on the matter.

RESULTS

Of 1264 articles screened, 36 were included in this systemic review, whereof 11 were eligible for data analysis and comparison. The average overall rate of maternal and obstetric complications corresponds to 78.6%. The majority of the described events are obstetric complications, varying from chorioamniotic membrane separation in 65.6% of cases, oligohydramnios in 13.0% of cases, placental abruption in 5.0% of cases, spontaneous or preterm premature membrane rupture in 42.0% of cases, and early preterm delivery in 11.3% of cases due to uterine dehiscence, occurring in 0.9% of cases. The most common medical complications are development of pulmonary edema occurring in 2.8%, gestational diabetes in 3.7%, gestational hypertension/preeclampsia in 3.7%, and need for blood transfusions in 3.2% of cases. Limitations of the review arise from the lack of data in the current literature, with maternal and obstetric complications being underreported.

CONCLUSIONS

Although the efforts of further advancement of intrauterine prenatal MMC repair aim to increase neonatal outcomes, maternal health hazard will continue to be an issue of crucial importance and further studies are required.

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Raphael Guzman, Arjun V. Pendharkar, Michel Zerah and Christian Sainte-Rose

Endoscopic third ventriculostomy (ETV) has become the procedure of choice for treatment of obstructive hydrocephalus. While patient selection is the most critical factor in determining the success of an ETV procedure, the technical challenge lies in the proper site of fenestration and the successful creation of a patent stoma. Positioning of a single balloon catheter at the level or below the floor of the third ventricle to achieve an optimal ventriculostomy can at times be challenging. Here, the authors describe the use of a double-barrel balloon catheter (NeuroBalloon catheter), which facilitates positioning across, as well as dilation of, the floor of the third ventricle. The surgical technique and nuances of using the NeuroBalloon catheter and the experience in more than 1000 cases are described. The occurrence of vascular injury was less than 0.1%, and the risk of balloon rupture was less than 2%. The authors found that the placement and deployment of this balloon catheter facilitate the creation of an adequate ventriculostomy in a few simple steps.

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Jan Gralla, Raphael Guzman, Caspar Brekenfeld, Luca Remonda and Claus Kiefer

Object. Conventional imaging for neuronavigation is performed using high-resolution computerized tomography (CT) scanning or a T1-weighted isovoxel magnetic resonance (MR) sequence. The extension of some lesions, however, is depicted much better on T2-weighted MR images. A possible fusion process used to match low-resolution T2-weighted MR image set with a referenced CT or T1-weighted data set leads to poor resolution in the three-dimensional (3D) reconstruction and decreases accuracy, which is unacceptable for neuronavigation. The object of this work was to develop a 3D T2-weighted isovoxel sequence (3D turbo—spin echo [TSE]) for image-guided neuronavigation of the whole brain and to evaluate its clinical application.

Methods. The authors performed a phantom study and a clinical trial on a newly developed T2-weighted isovoxel sequence, 3D TSE, for image-guided neuronavigation using a common 1.5-tesla MR imager (Siemens Sonata whole-body imager). The accuracy study and intraoperative image guidance were performed with the aid of the pointer-based Medtronic Stealth Station Treon.

The 3D TSE data set was easily applied to the navigational setup and demonstrated a high registration accuracy during the experimental trial and during an initial prospective clinical trial in 25 patients. The sequence displayed common disposable skin fiducial markers and provided convincing delineation of lesions that appear hyperintense on T2-weighted images such as low-grade gliomas and cavernomas in its clinical application.

Conclusions. Three-dimensional TSE imaging broadens the spectrum of navigational and intraoperative data sets, especially for lesions that appear hyperintense on T2-weighted images. The accuracy of its registration is very reliable and it enables high-resolution reconstruction in any orientation, maintaining the advantages of image-guided surgery.

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Raymond Choi, Robert H. Andres, Gary K. Steinberg and Raphael Guzman

Increasing evidence in animal models and clinical trials for stroke, hypoxic encephalopathy for children, and traumatic brain injury have shown that mild hypothermia may attenuate ischemic damage and improve neurological outcome. However, it is less clear if mild intraoperative hypothermia during vascular neurosurgical procedures results in improved outcomes for patients. This review examines the scientific evidence behind hypothermia as a treatment and discusses factors that may be important for the use of this adjuvant technique, including cooling temperature, duration of hypothermia, and rate of rewarming.

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Tae Sung Park

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Achal S. Achrol, Raphael Guzman, Marco Lee and Gary K. Steinberg

Moyamoya disease is an uncommon cerebrovascular condition characterized by progressive stenosis of the bilateral internal carotid arteries with compensatory formation of an abnormal network of perforating blood vessels providing collateral circulation.

The etiology and pathogenesis of moyamoya disease remain unclear. Evidence from histological studies, proteomics, and endothelial progenitor cell analyses suggests new theories underlying the cause of vascular anomalies, including moyamoya disease.

Familial moyamoya disease has been noted in as many as 15% of patients, indicating an autosomal dominant inheritance pattern with incomplete penetrance. Genetic analyses in familial moyamoya disease and genome-wide association studies represent promising strategies for elucidating the pathophysiology of this condition.

In this review, the authors discuss recent studies that have investigated possible mechanisms underlying the etiology of moyamoya disease, including stem cell involvement and genetic factors. They also discuss future research directions that promise not only to offer new insights into the origin of moyamoya disease but to enhance our understanding of new vessel formation in the CNS as it relates to stroke, vascular anomalies, and tumor growth.