bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of a hydrogel sealant improves watertight closures of duraplasty onlay grafts in a canine craniotomy model
Authors: Preul Mark C. , Campbell Patrick K. , Bichard William D. , Spetzler Robert F. 
Published: January 2008

Object
The authors evaluated whether a polyethylene glycol–based hydrogel sealant system improved dural closures with collagen-based duraplasty onlay grafts.

Methods
Dural defects 1.5 cm in diameter were created in 12 canines and repaired with one of two commercially available duraplasty onlay products. In six animals, hydrogel was applied onto the dural onlays, and the other six animals underwent duraplasty only. Before bone flap replacement, watertight closure was assessed. Before the animals were killed, the craniotomy was reopened, adhesions were rated by a neurosurgeon blinded to the treatment groups, and dural integrity was assessed using pressure testing.

Results
The animals that received the hydrogel sealant in addition to the duraplasty withstood intraoperative Valsalva maneuvers up to 20 cm H2O without cerebrospinal fluid (CSF) leakage. The duraplasty-only animals leaked CSF at spontaneous pressures (p = 0.0022). Postoperatively, all six duraplasty-only dogs developed CSF subcutaneous accumulations, compared with only one (16.7%) dog who underwent hydrogel application (p = 0.0152). At the time of harvesting (8 weeks after implantation), duraplasty-only dogs had extensive scarring between the bone flap and the dura mater (median adhesion score 4, range 3–4). The animals receiving hydrogel showed minimal scarring (median adhesion score 0.5, range 0–2). In hydrogel-treated dogs, the mean adhesion score was 82.6% lower than the scores in duraplasty-only animals (p = 0.0043). In animals receiving hydrogel, the mean dural leak pressure was 56.8 ± 2.5 cm H2O compared with 9.8 ± 3.8 cm H2O in duraplasty-only dogs (p = 0.0392). Application of the hydrogel was not associated with neurotoxicity, delayed healing, degenerative changes, or increased dura–cortex adhesions.

Conclusions
The hydrogel sealant applied to collagen-based dural grafts significantly reduced CSF leakage and functioned as an adhesion barrier. Such technology could be an important tool for cranial surgery.
Use of hinge craniotomy for cerebral decompression
Authors: Schmidt John H. , Reyes Bernardo J. , Fischer Roopan , Flaherty Sarah K. 
Published: January 2008

✓Decompressive craniectomy to relieve cerebral edema and intracranial hypertension due to traumatic brain injury is a generally accepted practice; however, the procedure remains controversial because of its uncertain effects on outcome, specific complications such as the syndrome of the sinking skin flap, and the need for subsequent cranioplasty. The authors developed a novel craniotomy technique using titanium bone plates in a hinged fashion, which maintains cerebral protection while reducing postoperative complications and eliminating subsequent cranioplasty procedures.
The authors conducted a retrospective review of data obtained in all consecutive patients who had undergone post-traumatic cerebral decompression craniotomy using the hinge technique at a Level I trauma facility between 1990 and 2004.
Twenty-five patients, most of whom were male (88%) and Caucasian (88%) with a mean age of 38.2 ± 16.1 years, underwent the hinge craniotomy. The in-hospital mortality rate was 48%, and good cerebral decompression was achieved. None of the patients required surgery for flap replacement. Long-term follow-up data showed that one patient required subsequent cranioplasty due to infection and one patient presented with cranial deformities. None of the patients presented with bone resorption or sinking flap syndrome.
The hinge technique effectively prevents procedure-related morbidity and the need for subsequent surgical bone replacement otherwise introduced by traditional decompressive craniectomy. A randomized controlled trial is required to substantiate these findings.
Quantitative analysis of the working area and angle of attack for the retrosigmoid, combined petrosal, and transcochlear approaches to the petroclival region
Authors: Siwanuwatn Rungsak , Deshmukh Pushpa , Figueiredo Eberval Gadelha , Crawford Neil R. , Spetzler Robert F. , Preul Mark C. 
Published: January 2008

Object
The authors quantitatively assessed the working areas and angles of attack associated with retrosigmoid (RS), combined petrosal (CP), and transcochlear (TC) craniotomies.

Methods
Four silicone-injected cadaveric heads were bilaterally dissected using three approaches progressing from the least to the most extensive. Working areas were determined using the Optotrak 3020 system on the upper and middle thirds of the petroclivus and brainstem. Angles of attack were studied using the Elekta SurgiScope at the Dorello canal and the origin of the anterior inferior cerebellar artery (AICA).
The TC approach provided significantly greater (p < 0.001) working areas at the petroclivus (755.6 ± 130.1 mm2) and brainstem (399.3 ± 68.2 mm2) than the CP (354.1 ± 60.3 and 289.7 ± 69.9 mm2) and RS approaches (292.4 ± 59.9, 177.2 ± 54.2 mm2, respectively). The brainstem working area associated with the CP approach was significantly larger (p < 0.001) than that associated with the RS route. There was no difference in the petroclival working area comparing the CP and RS approaches (p = 0.149). The horizontal and vertical angles of attack achieved using the TC approach were wider than those of the CP and RS at the Dorello canal and the origin of the AICA (p < 0.001).

Conclusions
The CP approach offers a more extensive working area than the RS for lesions involving the anterolateral surface of the brainstem, but not for petroclival lesions. The TC approach provides the widest corridor, improving the working area and angle of attack to both areas, but hearing must be sacrificed and the facial nerve is at risk.
Bromocriptine treatment of invasive giant prolactinomas involving the cavernous sinus: results of a long-term follow up
Authors: Wu Zhe Bao , Yu Chun Jiang , Su Zhi Peng , Zhuge Qi Chuan , Wu Jin Sen , Zheng Wei Ming 
Published: January 2008

Object
The aim of this study was to observe long-term clinical outcomes in a group of patients treated with bromocriptine for invasive giant prolactinomas involving the cavernous sinus.

Methods
Data from 20 patients with invasive giant prolactinomas at the authors’ institutions between July 1997 and June 2004 were retrospectively reviewed. The criteria to qualify for study participation included: 1) tumor diameter greater than 4 cm, invading the cavernous sinus to an extent corresponding to Grade III or IV in the classification scheme of Knosp and colleagues; 2) serum prolactin (PRL) level greater than 200 ng/ml; and 3) clinical signs of hyperprolactinemia and mass effect. Among the 20 patients who met the criteria, six had undergone unsuccessful transcranial or transsphenoidal microsurgery prior to bromocriptine treatment and 14 patients received bromocriptine as the primary treatment. Eleven of the 20 patients underwent adjuvant radiotherapy.
After a mean follow-up period of 37.3 months, the clinical symptoms in all patients improved by different degrees. Tumor volume on magnetic resonance images was decreased by a mean of 93.3%. In 11 patients, the tumor had almost completely disappeared; in the other nine patients, residual tumor invaded the cavernous sinus. Visual symptoms improved in 13 of the patients who had presented with visual loss. Eight patients had normal PRL levels. The postoperative PRL level was more than 200 ng/ml in seven patients. During the course of drug administration, cerebrospinal fluid leakage occurred in one patient, who subsequently underwent transsphenoidal surgery. No case of apoplexy occurred during bromocriptine treatment.

Conclusions
Dopamine agonist medications are effective as a first-line therapy for invasive giant prolactinomas, because they can significantly shrink tumor volume and control the PRL level. Tumor mass vanishes in some patients after bromocriptine treatment; in other patients with localized residual tumor, stereotactic radiosurgery is a viable option so that unnecessary surgery can be avoided. The application of radiotherapy does not reliably shrink tumor volume.
Development of a histological pseudocapsule and its use as a surgical capsule in the excision of pituitary tumors
Authors: Oldfield Edward H. , Vortmeyer Alexander O. 
Published: January 2008

Object
The presence of a histological pseudocapsule around pituitary tumors was noted in the early 1900s. Since that time there has been no emphasis on the sequence of the stages of its development or on the relationship between these stages and the capacity to identify very small pituitary tumors at surgery in patients in whom preoperative imaging has been nondiagnostic. In addition, limited emphasis has been given to the pseudocapsule’s use for selective and complete resection of pituitary adenomas.

Methods
The development of the pseudocapsule was examined by performing histological analysis of portions of pituitary glands removed during 805 operations for Cushing disease.
Twenty-five adenomas, each measuring between 0.25 and 4 mm in maximum diameter, were detected in the excised specimens; 17 were adenocorticotropic hormone–positive adenomas and eight were incidental tumors (four prolactin-secreting and four nonsecreting lesions). In 16 tumors the size of the adenoma could be established. The distribution of tumor size in relation to the presence of a histological pseudocapsule indicates a transition from the absence of a reticulin capsule (tumor diameter ≤ 1 mm) through the initial compression of surrounding tissue (tumor diameter 1–2 mm) to the presence of a multilayered reticulin capsule observed when adenomas become larger (tumor diameter 2–3 mm).

Conclusions
The absence of a reticulin capsule in cases of very small tumors may contribute to limited localization of these lesions during surgical exploration of the pituitary gland. In this article the authors describe surgical techniques in which the histological pseudocapsule is used as a surgical capsule during pituitary surgery. In their experience, recognition of this surgical capsule and its use at surgery has contributed to the identification of microadenomas buried in the pituitary gland, aided the recognition of subtle invasion of the pituitary capsule and contiguous dura mater, and enhanced the consistency of complete tumor excision with small and large tumors.
Unilateral vestibular schwannoma with other neurofibromatosis Type 2–related tumors: clinical and molecular study of a unique phenotype
Authors: Aghi Manish , Kluwe Lan , Webster Micah T. , Jacoby Lee B. , Barker Fred G. , Ojemann Robert G. , Mautner Victor-Felix , MacCollin Mia 
Published: January 2008

Object
Although the manifestations of neurofibromatosis Type 2 (NF2) vary, the hallmark is bilateral vestibular schwannomas (VSs). The authors studied the clinical course and genetic basis of unilateral VSs associated with other NF2-related tumors.

Methods
Forty-four adults presenting with unilateral VSs and other NF2-related tumors were identified. A comprehensive review of patient records and cranial imaging was conducted. Molecular analysis of the NF2 locus was performed in available tumors and paired blood specimens. Patient age at symptomatic onset ranged from 11 to 63 years (mean 32 years). Twenty-two patients (50%) presented with eighth cranial nerve dysfunction. Twenty-six presented with multiple lesions. Thirty-eight harbored other intracranial tumors and 27 had spinal tumors, with most lesions situated ipsilateral to the VS. No patient had a relative with NF2, although two of 63 offspring had isolated NF2-related findings. A contralateral VS developed in four patients 3 to 46 years after the symptomatic onset of a unilateral VS, and two of these patients experienced rapid progression to total deafness. Results of a Kaplan–Meier analysis identified actuarial chances of developing contralateral VS: 2.9% (3–17 years after the VS symptomatic onset of unilateral VS), 11% (18–24 years), and 28.8% (25–40 years). Mosaicism for the NF2 gene mutation was proven in eight patients.

Conclusions
The authors describe the clinical features of this unique phenotype—unilateral VS with other NF2-related tumors. Persons with this phenotype should undergo evaluation and monitoring similar to that conducted in patients with NF2, and the possibility of aggressive contralateral VS formation should be considered in their treatment. Molecular genetic analysis is best performed using resected tumor specimens and will enable future studies to determine the genetic risks of individuals with mosaicism.
Management of meningiomas en plaque of the sphenoid wing
Authors: Schick Uta , Bleyen Joris , Bani Alan , Hassler Werner 
Published: January 2008

Object
The authors present their findings on growth patterns in a large series of surgically treated meningiomas en plaque of the sphenoid wing.

Methods
A retrospective case analysis was performed in 67 patients (53 of whom were female) harboring meningiomas en plaque originating from the sphenoid wing, who underwent surgery between 1991 and 2002. The standard surgical approach consisted of pterional craniotomy and extradural resection of any infiltrated bone. The intracranial tumor was removed, and the dura mater and bone were reconstructed. The follow-up period ranged from 6 to 118 months (mean 45.7 months).
Total macroscopic resection was achieved in 40 patients. Forty-eight meningiomas extended to the orbital roof and/or the lateral orbital wall, 34 involved the extraconal space, and eight the intraconal space. Fifty-four tumors involved the superior orbital fissure, 46 the optic canal, and 21 the inferior orbital fissure. Twelve tumors infiltrated the cavernous sinus and 27 involved the anterior clinoid process. There were no deaths in this group of patients; the rate of minor morbidity was 11.9% and the rate of major morbidity was 3%. Subtotal resections were performed in 27 patients because there was intraorbital tumor (eight patients), tumor in the cavernous sinus (nine patients), tumor beyond the tentorial notch (three patients), tumor invading the superior orbital fissure (four patients), and tumor of the skull base (three patients). Five patients underwent postoperative three-dimensional conformal radiotherapy, which resulted in stable tumor volume at follow up. Tumor recurrence was identified in seven patients (10.4%) postoperatively (range of follow up 13–47 months).

Conclusions
The goal of surgery is complete tumor removal without morbidity. An exact analysis of tumor growth and its involvement of different structures is mandatory before performing surgery.
Complications of embolization of arteriovenous malformations of the brain
Authors: Haw Charles S. , terBrugge Karel , Willinsky Robert , Tomlinson George 
Published: January 2008

Object
The goal of this study was to determine the rates of mortality and morbidity associated with the embolization of arteriovenous malformations (AVMs) of the brain and to analyze the factors related to embolization-related complications.

Methods
The University of Toronto Brain Vascular Malformation Study Group database was reviewed. Three hundred six patients underwent 513 embolization sessions between November 1984 and September 2002. The combined rate of death and any permanent disabling neurological deficit was 3.9% per patient. Location of the AVM in an eloquent part of the brain, presence of a fistula, and a venous deposition of glue were related to complications. A clinically important reduction in the rate of death and disabling morbidity occurred in the second half of the study period.

Conclusions
Embolization of AVMs in the brain is associated with low overall rates of mortality and disabling morbidity.
Long-term recovery after bone marrow stromal cell treatment of traumatic brain injury in rats
Authors: Mahmood Asim , Lu Dunyue , Qu Changsheng , Goussev Anton , Chopp Michael 
Published: January 2008

Object
This study was designed to follow the effects of bone marrow stromal cell (BMSC) administration in rats after traumatic brain injury (TBI) for a 3-month period.

Methods
Forty adult female Wistar rats were injured by a controlled cortical impact and, 1 week later, were injected intravenously with one of three different doses of BMSCs (2 × 106, 4 × 106, or 8 × 106 cells per animal) obtained in male rats. Control rats received phosphate-buffered saline (PBS). Neurological function in these rats was studied using a neurological severity scale (NSS). The rats were killed 3 months after injury, and immunohistochemical stains were applied to brain samples to study the distribution of the BMSCs. Additional brain samples were analyzed by quantitative enzyme-linked immunosorbent assays to measure the expression of the growth factors brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF).
Three months after injury, BMSCs were present in the injured brain and their number was significantly greater in animals that received 4 × 106 or 8 × 106 BMSCs than in animals that received 2 × 106 BMSCs. The cells were primarily distributed around the lesion boundary zone. Functional outcome was significantly better in rats that received 4 × 106 or 8 × 106 BMSCs, compared with control animals, although no improvement was seen in animals that received 2 × 106 BMSCs. All doses of BMSCs significantly increased the expression of BDNF but not that of NGF; however, this increase was significantly larger in animals that received 4 × 106 or 8 × 106 BMSCs than in controls or animals that received 2 × 106 BMSCs.

Conclusions
In summary, when injected in rats after TBI, BMSCs are present in the brain 3 months later and significantly improve functional outcome.
Prevention of painful neuromas by oblique transection of peripheral nerves
Authors: Marcol Wieslaw , Kotulska Katarzyna , Larysz-Brysz Magdalena , Bierzyñska-Macyszyn Grazyna , Wlaszczuk Pawel , Lewin-Kowalik Joanna 
Published: January 2008

Object
Neuroma formation often occurs at the proximal stump of the transected nerve, complicating the healing process after gap injuries or nerve biopsies. Most such neuromas cause therapy-resistant neuropathic pain. The purpose of this study was to determine whether oblique transection of the proximal stump of the sciatic nerve can prevent neuroma formation.

Methods
The sciatic nerves of 10 rats were transected unilaterally at an angle of 30°, and the peripheral segments of the nerves were removed. In 10 control animals the sciatic nerves were transected at a perpendicular angle. Twenty weeks after surgery the nerves were reexposed and collected. The presence of neuromas was determined by two board-certified pathologists on the basis of histopathological evaluations.

Conclusions
The oblique transection of peripheral nerves, contrary to perpendicularly transected nerves, is rarely followed by classic neuroma development. Moreover, neuropathic pain is significantly reduced compared with that following the traditional method of nerve transection.
Effects of intravenous administration of human bone marrow stromal cells after intracerebral hemorrhage in rats
Authors: Seyfried Donald , Ding Jennifer , Han Yuxia , Li Yi , Chen Jieli , Chopp Michael 
Published: January 2008

Object
The goal of this study was to investigate whether human bone marrow stromal cells (hBMSCs) administered by intravenous injection have a beneficial effect on outcome after intracerebral hemorrhage (ICH) in rats.

Methods
An ICH was induced in 54 adult male Wistar rats by a stereotactically guided injection of autologous blood into the right striatum. Intravenous infusion of the hBMSCs (3, 5, or 8 million cells) was performed 1 day after ICH, and for each dose group there was a control group that received injections of vehicle. Neurological function, which was evaluated using the Neurological Severity Score (NSS) and the corner turn test, was tested before and at 1, 7, and 14 days after ICH. After 14 days of survival, the area of encephalomalacia was calculated and histochemical labeling was performed.
For all three groups, there were no statistical differences in either the NSS or corner turn tests after 1 day. After 7 and 14 days, however, the three groups that received the hBMSCs showed significant improvement in functional scores compared with the control group. In addition, after 14 days there was significantly more striatal tissue loss in the placebo groups compared with each of the three treatment groups. The region of injury in the treated animals demonstrated a significantly increased presence of hBMSCs, immature neurons, neuronal migration, synaptogenesis, and newly formed DNA.

Conclusions
Intravenous administration of hBMSCs significantly improves neurological function in rats subjected to ICH. This improvement in the treated animals is associated with reduced tissue loss and increased local presence of the hBMSCs, mitotic activity, immature neurons, synaptogenesis, and neuronal migration.
Pain in neurosurgically treated patients: a prospective observational study
Authors: Klimek Markus , Ubben Johannes F. H. , Ammann Jan , Borner Ulf , Klein Jan , Verbrugge Serge J. C. 
Published: January 2008

Object
This is the first observational study to compare perioperative pain character and intensity in patients undergoing different types of elective neurosurgical procedures.

Methods
A structured questionnaire was used to inquire about pain intensity, character, and management during the perioperative course, and the anticipated visual analogue scale (VAS) score in 649 patients during a 1-year period. The anticipated maximal postoperative VAS score was lower than the actual postoperative maximal VAS score and was independent of operation type and preoperative VAS score. Patients undergoing craniotomy experienced less pain than those undergoing spinal surgery. A majority of patients did not receive analgesic medication after surgery. Patients undergoing spinal surgery experienced higher preoperative VAS scores than those undergoing other neurosurgical treatments, with a shift from preoperative referred pain to postoperative local pain. After lumbar flavectomy, referred pain was greater than local pain. Patients with preoperative pain suffered significantly more postoperative pain than those without preoperative pain. In patients with postoperative surgery-related complications, VAS scores were higher than in those without complications.

Conclusions
Neurosurgical procedures cause more pain than anticipated. Anticipated pain intensity is independent of the operation type and preoperative pain intensity. Postcraniotomy on-demand analgesic medication is appropriate, if the nurses on the ward react quickly. Otherwise, patient-controlled analgesia might be an option. Other neurosurgical procedures require scheduled analgesic therapies. Spinal surgery requires intensive preoperative pain treatment; a shift in pain character from preoperative referred pain to postoperative local pain is expected. Patients with referred pain after lumbar flavectomy are prone to the most intense pain. Patients with preoperative pain experience more postoperative pain than those without preoperative pain and require more intensive pain management. Increased postoperative VAS scores are associated with surgery-related complications.