bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contribution of endovascular therapy to the management of poor-grade aneurysmal subarachnoid hemorrhage: clinical and angiographic outcomes
Authors: Suzuki Shuichi , Jahan Reza , Duckwiler Gary R. , Frazee John , Martin Neil , Viñuela Fernando 
Published: January 2008

Object
Treatment of patients presenting with poor-grade (Hunt and Hess Grade IV or V) subarachnoid hemorrhage (SAH) is controversial. Endovascular coil embolization has been considered a valuable therapeutic alternative to surgical clip placement for this kind of patient. The aim of the present study was to evaluate immediate and long-term angiographic and clinical outcomes in patients with poor-grade SAH treated by endovascular embolization.

Methods
One hundred eleven patients with Hunt and Hess Grade IV or V SAH were treated with endovascular embolization at the University of California at Los Angeles Medical Center between October 1990 and December 2004. Eighty patients harbored Grade IV hemorrhages and 31 patients had Grade V ones. Immediate and long-term anatomical and clinical outcomes were evaluated in all patients. Long-term clinical outcome assessments were based on follow-up data obtained over an average of 32 months posttherapy.
Technical complications occurred in 15 patients (13.5%). Immediate complete aneurysm occlusion was observed in 51.4% of aneurysms. Angiographic, long-term follow-up review revealed aneurysm recanalization in 16.2% of cases. Thirty-nine patients (35.1%) demonstrated a favorable long-term clinical outcome. The overall mortality rate in this patient series was 32.4%. The mortality rate associated with vasospasm was significantly higher in patients with Grade IV SAHs than in those with Grade V hemorrhages.

Conclusions
The results of this study demonstrate a valuable contribution of endovascular therapy of ruptured intracranial aneurysms in patients with Hunt and Hess Grade IV or V SAH. This technique was successful in decreasing repeated aneurysm rupture and in enabling aggressive medical management during the acute phase of SAH. This is particularly important in patients with Grade IV SAH because of their potential for obtaining higher physical and functional recoveries.
Monitoring of muscle motor evoked potentials during cerebral aneurysm surgery: intraoperative changes and postoperative outcome
Authors: Szelényi Andrea , Langer David , Kothbauer Karl , de Camargo Adauri Bueno , Flamm Eugene S. , Deletis Vedran 
Published: January 2008

Object
The authors in this study evaluated muscle motor evoked potentials (MMEPs) elicited by transcranial electrical stimulation (TES) and direct cortical stimulation as a means of monitoring during cerebral aneurysm surgery. The analysis focused on the value and frequencies of any intraoperative changes and their correlation to the postoperative motor status.

Methods
One hundred nineteen patients undergoing surgery for 148 cerebral aneurysms were included in the study. Muscle motor evoked potentials were elicited by a train of five constant-current anodal stimuli with an individual pulse duration of 0.5 msec and a stimulation rate of 2 Hz. Stimulation intensity was up to 240 mA for TES and up to 33 mA for direct cortical stimulation. The MMEPs were continuously recorded from the abductor pollicis brevis and tibialis anterior muscles bilaterally and from the biceps brachii and extensor digitorum communis muscles contralateral to the surgical side. The motor status was evaluated immediately after surgery and 7 days later.
In 97% of the patients MMEPs were recordable for continuous neurophysiological monitoring of the vascular territory of interest throughout the surgery. In 14 patients significant intraoperative MMEP changes occurred, resulting in a transient motor deficit in one patient and a permanent motor deficit in six. The permanent loss of MMEPs in three patients was followed by a permanent severe motor deficit in one patient and severe clinical deterioration in the other two.

Conclusions
Data in this study demonstrated that MMEPs are a useful means of intraoperative neurophysiological monitoring of motor pathway integrity and predicting postoperative motor status. The intraoperative loss of MMEPs reliably predicts both severe and permanent postoperative motor deficits.
Multislice computed tomography angiography screening for new aneurysms in patients with previously clip-treated intracranial aneurysms: feasibility, positive predictive value, and interobserver agreement
Authors: van der Schaaf Irene C. , Velthuis Birgitta K. , Wermer Marieke J. H. , Frenkel Nanne J. , Majoie Charles B. L. M. , Witkamp Theo D. , de Kort Gerard , Freling Nicole J. , Rinkel Gabriel J. E. , _ _ 
Published: January 2008

Object
Multislice computed tomography (CT) angiography may be useful for screening patients with intracranial aneurysms that are treated with clip occlusion. However, cobalt clips produce much more artifact on CT scans than titanium clips, which may hamper the evaluation of the image obtained at the clip site.

Methods
The authors screened 415 patients with previously ruptured aneurysms that had been treated using cobalt clips. Screening was performed using multislice CT angiography. The feasibility of this modality for screening these patients (based on the complication risk, CT angiography quality, and artifact avoidance) and interobserver agreement were evaluated. Patients in whom the presence of an aneurysm was suspected based on results of CT angiography studies underwent digital subtraction (DS) angiography. False-negative and false-positive findings were recorded, and the positive predictive value (PPV) was calculated.
Eight patients (1.9%) had allergies to the contrast material. The quality of the CT angiography image was suboptimal in 14%. In 52%, clip artifacts hampered evaluation of the clip site. In 65 patients who underwent DS angiography, there were nine false-positive and eight false-negative reports related to aneurysms that were either small, located at the clip site, or were infundibula. The PPV on a per-patient basis was 86% (95% confidence interval [CI] 75–94%); for aneurysms at the clip site it was 83% (95% CI 61–95%); and for aneurysms at different locations it was 91% (95% CI 81–97%). The interobserver agreement was good (κ = 0.69; 95% CI 0.60–0.78).

Conclusions
Except for the evaluation of images from the clip site, CT angiography has good feasibility with good PPV and interobserver agreement. Drawbacks are that very small aneurysms can be missed and that visualization is poor at the clip site in patients in whom cobalt clips have been placed for occlusion. This second problem can be expected to resolve with the increasing use of titanium clips.
Split facial nerve course in vestibular schwannomas
Authors: Strauss Christian , Prell Julian , Rampp Stefan , Romstöck Johann 
Published: January 2008

Object
The facial nerve in vestibular schwannomas (VSs) is located on the ventral tumor surface in more than 90% of cases; other courses are rare. A split facial nerve course with two distinct bundles has thus far been described exclusively for medial extrameatal tumors.

Methods
Between 1996 and 2005, 16 consecutive cases of 241 surgically treated VSs were observed to have distinct splitting of the facial nerve. The mean tumor size measured 27 mm. In one third of the cases, intrameatal tumor extension with obliteration of the fundus was documented. All patients underwent extensive intraoperative neurophysiological monitoring using multichannel electromyography recordings. Patients were reevaluated 12 months after surgery.
In all 16 patients, distinct splitting of the facial nerve was demonstrated. The major portion of the facial nerve followed a typical course on the ventral tumor surface. The smaller nerve portion in all cases ran parallel to the brainstem up to the level of the trigeminal root exit zone and crossed on the cranial tumor pole to the internal auditory canal. The two nerve portions rejoined at the level of the porus acusticus. The smaller portion carried fibers exclusively to the orbicularis oris muscle, whereas the major portion supplied all three branches of the facial nerve.

Conclusions
In VSs, an aberrant course with distinct splitting of the facial nerve adds considerably to the surgical challenge. Long-term facial nerve results are excellent with extensive neurophysiological monitoring, which allows the differentiation and identification of aberrant facial nerve fibers and avoids additional risks to facial nerve preservation.
Intrasaccular combination of metallic coils and Onyx liquid embolic agent for the endovascular treatment of cerebral aneurysms
Authors: Cekirge H. Saruhan , Saatci Isil , Geyik Serdar , Yavuz Kivilcim , Öztürk Halil , Pamuk Gülsün 
Published: January 2008

Object
The aim of this study was to report on a novel technique in which metallic embolization coils were combined with the Onyx liquid embolic agent in the aneurysm sac to achieve a more durable result after endovascular treatment. This therapeutic procedure was performed in selected cases in which, based on the authors’ experiences, either coil embolization or Onyx alone would likely have failed. The authors report long-term clinical and angiographic follow-up results in 20 consecutive intracranial aneurysms treated using this combination for defined indications.

Methods
Twenty aneurysms in 20 patients were treated with a combination of embolic coils and Onyx. Four aneurysms were giant; 13, large; and three, small. This new technique was used when standard Onyx or coil treatment with balloon assistance was determined to involve a higher possibility of recanalization, because either an adjunctive stent insertion could not be performed or the Onyx technique could not be used due to an unsuccessful seal test or intraaneurysm balloon prolapse. In one case, an adjunctive stent was placed before coil placement and Onyx deposition to control the material in the sac of the aneurysm, which had a fusiform neck.
All aneurysms were completely occluded after using this technique. No clinical or technical adverse events occurred in any of the cases. Follow-up angiography was performed in all patients: 3-year studies in six patients, 2-year studies in five, and 1-year studies in nine. None of these studies demonstrated aneurysm regrowth or parent artery occlusion.

Conclusions
The combination of the embolic coils and the Onyx liquid embolic agent provides very durable aneurysm occlusion for defined indications.
Using endothelial nitric oxide synthase gene polymorphisms to identify intracranial aneurysms more prone to rupture in Japanese patients
Authors: Krischek Boris , Kasuya Hidetoshi , Akagawa Hiroyuki , Tajima Atsushi , Narita Akira , Onda Hideaki , Hori Tomokatsu , Inoue Ituro 
Published: January 2008

Object
Recent investigators found that the presence of three tandem polymorphisms of the endothelial nitric oxide synthase (eNOS) gene—promoter single nucleotide polymorphism (SNP) T-786C, intron-4 27-bp variable number of tandem repeats, and the G894T SNP in exon 7—was indicative of intracranial aneurysms more prone to rupture in a Caucasian patient sample. In the present study, the authors sought to determine whether the presence of these eNOS polymorphisms could indicate which Japanese patients with aneurysms were more endangered by a subarachnoid hemorrhage (SAH).

Methods
The three eNOSpolymorphisms were genotyped in 297 patients with ruptured aneurysms (RAs), 108 patients with unruptured aneurysms (UAs), and 176 healthy volunteers by using polymerase chain reaction.
The distribution of the variant alleles did not differ significantly (p > 0.05) between the RA group and the UA group. The frequency of the corresponding genotypes between the two groups and a haplotype analysis did not show any significant differences. Further comparisons of the RA and UA groups with the control group did not yield any significant allele or genotype frequency differences.

Conclusions
These data show that the examined set of eNOS polymorphisms were not indicative of which Japanese patients with intracranial aneurysms would suffer an SAH. The presence of eNOS polymorphisms is not useful in identifying intracranial aneurysms that are more prone to rupture in a Japanese patient sample.
Oncocytic meningiomas: cases with benign histopathological features and a favorable clinical course
Authors: Gallina Pasquale , Buccoliero Anna Maria , Mariotti Furio , Mennonna Pasquale , di Lorenzo Nicola 
Published: January 2008

Object
Oncocytic meningioma has recently been recognized as a distinct morphological variant of intracranial meningothelial neoplasms, and only a few cases have been reported in the literature. The first description of this lesion, which was based on data in six cases, revealed a potentially aggressive nature with a tendency to infiltrate the brain and to recur. However, the true behavior of, and the long-term follow-up data for, such lesions must still be outlined.

Methods
The authors report on five cases of intracranial oncocytic meningiomas. On neuroimaging, the lesions showed the characteristic features of common meningiomas. All patients underwent gross-total removal of the mass together with the adjacent dura mater. No additional treatments were administered. Histologically, the tumors were composed of sheets, nests, and cords of large polygonal neoplastic cells with finely granular cytoplasm. Necrosis was absent in all cases. Mitosis was also absent or exceedingly rare, and no brain cortex infiltration was observed. The follow up ranged from 6 to 54 months (mean 32.4 months). At the last follow-up evaluation, all patients were asymptomatic and magnetic resonance imaging examinations demonstrated no evidence of tumor recurrence.

Conclusions
Data in the presented cases did not confirm a previously described propensity to aggressiveness in this meningioma subtype. In fact, the histological features as well as the long-term favorable clinical course may suggest benign behavior of such neoplasms, as in the common forms of meningiomas.
Expanded polytetrafluoroethylene graft for bypass surgery using the excimer laser–assisted nonocclusive anastomosis technique
Authors: Reinert Michael , Verweij Bon H. , Schaffner Thomas , Mihalache George , Schroth Gerhard , Seiler Rolf W. , Tulleken Cornelis A. F. 
Published: January 2008

Object
Patients with complex craniocerebral pathophysiologies such as giant cerebral aneurysms, skull base tumors, and/or carotid artery occlusive disease are candidates for a revascularization procedure to augment or preserve cerebral blood flow. However, the brain is susceptible to ischemia, and therefore the excimer laser–assisted nonocclusive anastomosis (ELANA) technique has been developed to overcome temporary occlusion. Harvesting autologous vessels of reasonable quality, which is necessary for this technique, may at times be problematic or impossible due to the underlying systemic vascular disease. The use of artificial vessels is therefore an alternative graft for revascularization. Note, however, that it is unknown to what degree these grafts are subject to occlusion using the ELANA anastomosis technique. Therefore, the authors studied the ELANA technique in combination with an expanded polytetrafluoroethylene (ePTFE) graft.

Methods
The experimental surgeries involved bypassing the abdominal aorta in the rabbit. Ten rabbits were subjected to operations representing 20 ePTFE graft–ELANA end-to-side anastomoses. Intraoperative blood flow, follow-up angiograms, and long-term histological characteristics were assessed 75, 125, and 180 days postoperatively. Angiography results proved long-term patency of ePTFE grafts in all animals at all time points studied. Data from the histological analysis showed minimal intimal reaction at the anastomosis site up to 180 days postoperatively. Endothelialization of the ePTFE graft was progressive over time.

Conclusions
The ELANA technique in combination with the ePTFE graft seems to have favorable attributes for end-to-side anastomoses and may be suitable for bypass procedures.
Endovascular surgery for very small ruptured intracranial aneurysms
Authors: Suzuki Sachio , Kurata Akira , Ohmomo Taketomo , Sagiuchi Takao , Niki Jun , Yamada Masaru , Oka Hidehiro , Fujii Kiyotaka , Kan Shinichi 
Published: January 2008

✓Application of endovascular surgery for very small aneurysms is controversial because of technical difficulties and high complication rates. The aim in the present study was to assess treatment results in a series of such lesions at one institution.
Since 1997, endovascular surgery has been advocated for very small ruptured aneurysms (<3 mm in maximum diameter) that fulfill the criterion of a fundus/neck ratio greater than 1.5. Twenty-one patients were treated, for whom the World Federation of Neurosurgical Societies classification before treatment was Grade I in 10, Grade II in two, Grade III in two, Grade IV in five, and Grade V in two. The aneurysm location was the internal carotid artery in four, the anterior communicating artery in 11, the middle cerebral artery in one, and the vertebrobasilar system in five. In all patients, endovascular surgery was performed using Guglielmi detachable coils after induction of general anesthesia. Initially, the presumed volume of the lesions was calculated for each aneurysm. Thereafter, the appropriate coil length was decided according to the volume embolization ratio, as 30 to 40%. In all attempts to obliterate aneurysms a single coil was used.
All aneurysms were completely obliterated as confirmed by postembolization angiography, without procedure-related complications. During the follow-up period only one patient needed additional coil embolization for a growing aneurysm. Final outcomes were good recovery in 15 patients, moderate disability in five, and severe disability in one.
Appropriate selection of patients and coils, and use of sophisticated techniques allow a good outcome for patients with very small aneurysms.
Use of clinical signs and computed tomography myelography findings in detecting and excluding nerve root avulsion in complete brachial plexus palsy
Authors: Bertelli Jayme Augusto , Ghizoni Marcos Flávio 
Published: January 2008

Object
The purpose of this study was to investigate the usefulness of preoperative evaluation based on clinical testing and computed tomography (CT) myelography in differentiating root rupture (that is, graftable root) from root avulsion in total brachial plexus palsy.

Methods
Thirty-two patients with total brachial plexus palsy were clinically tested for the presence of phrenic nerve palsy, supraclavicular Tinel sign, shoulder protraction, Bernard–Horner syndrome, and hand pain. The patients underwent CT myelography and then underwent surgery. The combination of a positive Tinel sign and a positive shoulder protraction test accurately predicted the presence of a graftable root in 93.7% of the cases. A 96.8% rate of accuracy was attained if the results of the CT myelography were considered together with the clinical signs. The presence of Bernard–Horner syndrome and hand pain accurately indicated avulsion of the lower roots in 93.7% of the patients. Computed tomography myelography accurately predicted the condition of the lower roots in 100% of the cases. Total avulsion injury was observed in five cases (16%). The lower roots were avulsed in 94% of the cases. The C-5 and C-6 roots were grafted 40 times, and a suitable root stump for grafting lay in a retroscalenic position in 18 (45%) of the 40 cases.

Conclusions
Preoperative assessment based on clinical examination and CT myelography allowed correct surgical planning in more than 90% of the cases.
Effectiveness and handling characteristics of a three-layer polymer dura substitute: a prospective multicenter clinical study
Authors: Messing-Jünger A. Martina , Ibáñez Javier , Calbucci Fabio , Choux Maurice , Lena Gabriel , Mohsenipour Iradj , Van Calenbergh Frank 
Published: January 2008

Object
The goal of this study was to assess the effectiveness and handling characteristics of a dura substitute composed of two outer layers of expanded polytetrafluoroethylene (PTFE) and a middle layer consisting of an elastomeric fluoropolymer.

Methods
In a prospective multicenter study, the dura substitute was implanted using a standard technique in 119 patients undergoing cranial or spinal surgery requiring duraplasty. Intraoperative assessments of the dura patch consisted of testing for cerebrospinal fluid (CSF) leakage employing the Valsalva maneuver and a surgeon’s standard evaluation of the handling characteristics of the device. Postoperative assessments conducted during a mean follow-up time of 15.7 months (range 0.3–45.6 months) consisted of physical examinations, routine computed tomography (CT) or magnetic resonance (MR) imaging studies, and histological studies of any removed dura patches.
The mean age of the 119 patients was 40 years (range < 1–81 years). The dura substitute was implanted cranially in 102 patients and spinally in 17. Intraoperative assessment including the Valsalva maneuver led to application of additional sutures in 17 patients. Handling features were rated very good to excellent. Postoperative clinical evaluation resulted in 79 excellent and 18 good results. Imaging studies (MR imaging studies in 69 patients and CT studies in 34 patients) showed no adhesions in 87 patients and minimal adhesions in seven patients (the dura was not visualized in nine patients). Postoperative complications occurred in 12 patients. There were six cases of CSF leakage, three cases of extradural hematoma, one case of arachnoid fibrosis after decompression of a Chiari malformation Type I, and two cases of infection. Eight (7%) of these complications were potentially related to the dura patch.

Conclusions
In a large, multicenter clinical study of the use of an expanded-PTFE–containing dura substitute, the device was found to be easy to handle and implant. No serious dura patch–related intraoperative adverse events were observed. Postoperatively, there were no major sealing problems or long-term complications. In two cases the patch had to be removed due to fibrosis and infection. The three-layer polymer dura substitute appears to be safe and effective in minimizing CSF leakage and adhesion formation, and its use avoids any risk of prion disease transmission.
Using an end-to-side interposed sural nerve graft for facial nerve reinforcement after vestibular schwannoma resection
Authors: Samii Madjid , Koerbel Andrei , Safavi-Abbasi Sam , Di Rocco Federico , Samii Amir , Gharabaghi Alireza 
Published: January 2008

✓ Increasing rates of facial and cochlear nerve preservation after vestibular schwannoma surgery have been achieved in the last 30 years. However, the management of a partially or completely damaged facial nerve remains an important issue. In such a case, several immediate or delayed repair techniques have been used.
On the basis of recent studies of successful end-to-side neurorrhaphy, the authors applied this technique in a patient with an anatomically preserved but partially injured facial nerve during vestibular schwannoma surgery. The authors interposed a sural nerve graft to reinforce the facial nerve whose partial anatomical continuity had been preserved. On follow-up examinations 18 months after surgery, satisfactory cosmetic results for facial nerve function were observed.
The end-to-side interposed nerve graft appears to be a reasonable alternative in cases of partial facial nerve injury, and might be a future therapeutic option for other cranial nerve injuries.