bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebral blood flow patterns at major vessel bifurcations and aneurysms in rats
Authors: Nakatani Hideyuki , Hashimoto Nobuo , Kang Yoo , Yamazoe Naohiro , Kikuchi Haruhiko , Yamaguchi Saburo , Niimi Hideyuki
Published: May 2009

✓ Cerebral arterial bifurcations in rats were treated to induce cerebral aneurysms experimentally, and flow patterns of latex particles introduced under a constant flow rate were analyzed with a 16-mm cine-camera and videocassette recorder. Cerebral aneurysms were produced by ligating one common carotid artery, inducing experimental hypertension, and feeding the animals β-aminopropionitrile. After perfusion and fixation, samples of cerebral arterial bifurcations with shallow invaginations and with small aneurysms were obtained and used for analysis. Bifurcations in rats without experimental treatment were used as control specimens. Flow studies in the control bifurcations showed that the apical intimal pad, not the apex itself, acted as the flow divider. Small particles tended to accumulate at the region just distal to the apical intimal pad, where the initial aneurysmal changes are known to occur. This indicates stagnation of flow at that site. In the bifurcations with shallow invaginations and small aneurysms, a marked pressure gradient was present at the proximal end of the aneurysm orifice. A tendency for stagnation of small particles near the aneurysm wall was also observed. The wall shear stress was highest at the distal end of the aneurysmal orifice, which may be responsible for the development of these lesions.
The effects of etomidate on cerebral metabolism and blood flow in a canine model for hypoperfusion
Authors: Frizzell R. Tyler , Meyer Yves J. , Borchers D. John , Weprin Bradley E. , Allen Elizabeth C. , Pogue W. Rene , Reisch John S. , Cherrington Alan D. , Batjer H. Hunt
Published: May 2009

✓ The effects of etomidate, a nonbarbiturate cerebral metabolic depressant, on cerebral metabolism and blood flow were studied in 29 dogs during cerebral hypoperfusion. Three groups of animals were studied during a 45-minute normotensive and a 30-minute hypotensive period: 10 control animals without etomidate, 11 animals receiving a 0.1-mg/kg etomidate bolus followed by an infusion of 0.05 mg/kg/min etomidate (low-dose group), and eight animals receiving doses of etomidate sufficient to suppress electroencephalographic bursts (high-dose group). The mean arterial pressure fell to similar levels (p < 0.05) during hypotension in all three groups (40 ± 5, 38 ± 3, and 27 ± 6 mm Hg, respectively). The mean cerebral oxygen extraction fraction rose (p < 0.05) from 0.23 ± 0.02 to 0.55 ± 0.08 in the five control animals tested and from 0.33 ± 0.02 to 0.53 ± 0.02 in the seven animals tested in the low-dose group, but did not increase (p > 0.05) in the four animals tested in the high-dose group (0.24 ± 0.03 to 0.23 ± 0.05). Mean cerebral blood flow levels decreased in all groups during hypotension (p < 0.05): 42 ± 3 to 21 ±4 ml/100 gm/min (52% ± 12% decrease) in the five animals tested in the control group, 60 ± 8 to 24 ± 6 ml/100 gm/min (56% ± 13% decrease) in the four animals tested in the low-dose group, and 55 ± 8 to 22 ± 3 ml/100 gm/min (60% ± 4% decrease) in the four animals tested in the high-dose group. In summary, the cerebral oxygen extraction fraction increased in the control animals and low-dose recipients during hypotension, suggesting the presence of threatened cerebral tissue. In contrast, the cerebral oxygen extraction did not change during hypotension when high-dose etomidate was administered. It is concluded that high-dose etomidate may preserve the cerebral metabolic state during hypotension in the present model.
Treatment of intractable arterial hemorrhage during stereotactic brain biopsy with thrombin
Authors: Chimowitz Marc I. , Barnett Gene H. , Palmer Joann
Published: May 2009

✓ Of 165 consecutive patients undergoing computerized tomography- or magnetic resonance imaging-guided stereotactic brain biopsies at the Cleveland Clinic between June, 1987, and November, 1989, four patients (2.4%) developed arterial hemorrhage refractory to conventional efforts to secure hemostasis. Craniotomy was performed in one of these patients to control the hemorrhage; in the other three, 0.5 to 2 cc of thrombin (5000 U/cc) was slowly injected via the biopsy cannula, resulting in immediate control of bleeding in all three cases. Postoperatively, the first two patients treated with 1 to 2 cc of thrombin were slow to awaken; one had evidence of vasospasm by transcranial Doppler ultrasound studies and multiple infarcts on cranial computerized tomography, while the other had a moderate-sized frontal hematoma with intracranial hypertension. After prolonged recovery periods, only mild neurological deficits persisted in both patients. The third patient, treated with 0.5 cc of thrombin, had an uneventful postoperative course. Thrombin is highly effective for stopping intractable arterial hemorrhage during stereotactic brain biopsy; however, it is a vasospastic agent and may have been responsible for the cerebral infarctions in one patient. Therefore, thrombin should be used only as a last resort, short of craniotomy, to control intractable arterial hemorrhage during stereotactic brain biopsy.
Functional outcomes following selective posterior rhizotomy in children with cerebral palsy
Authors: Peacock Warwick J. , Staudt Loretta A.
Published: May 2009

✓ The recent increase in popularity of selective posterior rhizotomy demands objective documentation of surgical outcome. For this reason, the authors have analyzed the status of 25 children with spastic cerebral palsy before and after rhizotomy to determine the effects of this therapy on muscle tone, range of movement, and motor function. Postoperative tests showed a reduction in muscle tone compared with preoperative assessments. Range of motion in the lower extremities was significantly increased and improvements in functional gross motor skills were noted. An increase in range of motion in the knees and thighs during gait was detected in 18 ambulatory patients studied with computerized two-dimensional motion analysis. Preliminary findings indicate that selective posterior rhizotomy reduced spasticity, thereby increasing range of motion and contributing to improvements in active functional mobility.
Endovascular occlusion of vertebral arteries in the treatment of unclippable vertebrobasilar aneurysms
Authors: Aymard Armand , Gobin Y. Pierre , Hodes Jonathan E. , Bien Siegfried , Rüfenacht Daniel , Reizine Daniel , George Bernard , Merland Jean J.
Published: May 2009

✓ Twenty-one patients with aneurysms of the vertebrobasilar circulation underwent unilateral or bilateral endovascular occlusion of the vertebral artery. Six patients presented with subarachnoid hemorrhage (SAH), 10 with mass effect, four with mass effect and SAH, and one with ischemic symptoms. Thirteen patients had good outcomes with complete clinical and angiographic cure. Six patients had partial thrombosis of their aneurysms. There was one death and one treatment failure. One patient suffered transient stroke. It is concluded that endovascular occlusion of the vertebral artery following test occlusion is a safe and effective treatment for proximal aneurysms of the vertebrobasilar circulation.
Acute regional cerebral blood flow changes caused by severe head injuries
Authors: Marion Donald W. , Darby Joseph , Yonas Howard
Published: May 2009

✓ To evaluate the changes in cerebral blood flow (CBF) that occur immediately after head injury and the effects of different posttraumatic lesions on CBF, 61 CBF studies were obtained using the xenon-computerized tomography method in 32 severely head-injured adults (Glasgow Coma Scale score (GCS) ≤ 7). The measurements were made within 7 days after injury, 43% in the first 24 hours. During the 1st day, patients with an initial GCS score of 3 or 4 and no surgical mass had significantly lower flows than did those with a higher GCS score or mass lesions (p < 0.05): in the first 1 to 4 hours, those without surgical mass lesions had a mean CBF of 27 cc/100 gm/min, which rose to 44 cc/100 gm/min by 24 hours. Patients without surgical mass lesions who died tended to have a lower global CBF than did those with better outcomes. Mass lesions were associated with a high global CBF and bihemispheric contusions with the lowest flows. By 24 hours after injury, global blood flow increased in groups that originally had low flows and decreased in those with very high initial flows, such that by 36 to 48 hours, most patients had CBF values between 32 and 55 cc/100 gm/min. Lobar, basal ganglion, and brain-stem blood flow values frequently differed by 25% or more from global averages. Brain-stem CBF varied the most but did not correlate with clinical signs of brain-stem dysfunction. Double studies were performed at two different pCO2 values in 10 patients with various posttraumatic lesions, and the CO2 vasoresponsivity was calculated. Abnormal CO2 vasoresponsivity was found with acute subdural hematomas and defuse cerebral swelling but not with epidural hematomas. In patients without surgical mass lesions, the findings suggest that CBF in the first few hours after injury is often low, followed by a hyperemic phase that peaks at 24 hours. Global CBF values vary widely depending on the type of traumatic brain injury, and brain-stem flow is often not accurately reflected by global CBF values. These findings underscore the need to define regional CBF abnormalities in victims of severe head injury if treatment is intended to prevent regional ischemia.
Spontaneous neuronal hyperactivity in the medial and intralaminar thalamic nuclei of patients with deafferentation pain
Authors: Rinaldi Patricia C. , Young Ronald F. , Albe-Fessard Denise , Chodakiewitz Jacob
Published: May 2009

✓Electrical activity was recorded from single cells in the thalamus of 10 patients with chronic pain associated with deafferentation. Under local anesthesia, these patients underwent either electrode implantation or thalamotomy for treatment of their pain. In eight of the 10 patients, single units were identified as discharging spontaneously in high-frequency, often rhythmic, bursts. The discharges were of two types: short bursts comprised of two to six spikes with a burst frequency of one to four per second; and long trains of 30 to 80 spikes of similar frequency. Reconstruction of electrode trajectories indicated that recordings were made from the region corresponding to the lateral aspect of the mediodorsal thalamic nucleus, the central lateral nucleus, a small part of the central median nucleus, and the parafascicular nucleus. In the eight patients in whom spontaneous neuronal burst activity was exhibited, it was impossible to study activity evoked by natural cutaneous stimulation due to the continuous spontaneous neuronal discharges.

Both animal and human studies have suggested that pain related to deafferentation is accompanied by spontaneous hyperactivity in the dorsal horn of the spinal cord and in the ventral posterior thalamic nuclei. The authors present evidence of spontaneous neuronal hyperactivity in the intralaminar thalamic nuclei of patients with pain related to deafferentation. The findings suggest that spontaneous neuronal discharge in patients with pain related to deafferentation is more widespread in the central nervous system than has been previously appreciated. The results have important implications for the surgical treatment of chronic pain.
Osteopromotion for cranioplasty
Authors: Dahlin Christer , Alberius Per , Linde Anders
Published: May 2009

✓ Various techniques for treatment of large cranial defects have been reported, but the use of alloplastic materials still seems to predominate. The authors have applied and explored a new approach for bone repair which appears promising, even for use in less osteogenic environments such as the adult calvaria. Seventy-two adult Sprague-Dawley rats each received bilateral 8-mm trephine defects in the temporoparietal area; this defect size precludes spontaneous osseous healing during the lifetime of the animal. Five surgical procedures, employing various alternatives of biologically inert expanded polytetrafluoroethylene membrane positioning and intramembranous bone-chip implantation, were performed and compared to control defects. Slight improvement of bone regeneration was demonstrated with subperiosteal ectocranial and endocranial membranes, alone or in combination, and with bone chips alone or in combination with an outer or inner membrane. Virtually complete bone healing was observed in animals receiving both an outer and an inner membrane with interpositioned bone chips. The latter appeared to function primarily as space-holders by keeping the membranes separated throughout the defect. Consequently, this technique seems to significantly promote bone repair by excluding soft-tissue components from the bone-healing site.
Tethered cord syndrome from a choristoma of müllerian origin
Authors: Molleston Michael C. , Roth Kevin A. , Wippold Franz J. , Grubb Robert L.
Published: May 2009

✓ The authors report a case of tethered cord syndrome due to a choristoma of müllerian origin located in the spinal cord at the lumbosacral junction. Two similar cases were found upon review of the literature. The embryology of this lesion is discussed.
Subarachnoid hemorrhage from a dissecting aneurysm of the middle cerebral artery
Authors: Sasaki Osamu , Koike Tetsuo , Tanaka Ryuichi , Ogawa Hiroshi
Published: May 2009

✓ A case of subarachnoid hemorrhage (SAH) from a dissecting aneurysm of the inferior limb of the middle cerebral artery is reported. The patient's clinical status and the initial and follow-up angiographic appearance of the aneurysm are presented. Diagnosis and treatment are briefly discussed. It is suggested that, if angiography demonstrates luminal narrowing or vascular occlusion in a patient with unexplained SAH, a dissecting aneurysm of the carotid system should be considered as a cause of the hemorrhage.
Stereotactic radiosurgery of meningiomas
Authors: Kondziolka Douglas , Lunsford L. Dade , Coffey Robert J. , Flickinger John C.
Published: May 2009

✓ Stereotactic radiosurgery has an expanding role in the management of selected intracranial tumors. In an initial 30-month experience using the 201-source cobalt-60 gamma knife at the University of Pittsburgh, 50 patients with meningiomas were treated. The most frequent site of origin was the skull base. Previously, 36 patients (72%) had undergone at least one craniotomy and four patients (8%) had received fractionated external beam radiation therapy. Stereotactic radiosurgery was the primary treatment modality in 16 patients (32%) with symptomatic tumors demonstrated by neuroimaging. Computer imaging-generated isodose plans (with one to five irradiation isocenters) for single-treatment irradiation gave optimal (≥ 50% isodose line) coverage in 44 patients (88%). The proximity of cranial nerves or vascular, pituitary, and brain-stem structures to the often convoluted tumor mass was crucial to dose selection. Serial imaging studies were evaluated in all 50 patients. Twenty-four patients were examined between 12 and 36 months after treatment; 13 (54%) showed a reduction in tumor volume while nine (38%) showed no change. Of 26 patients evaluated between 6 and 12 months after treatment, four showed a decrease in tumor size while 22 showed no change. Two patients (both with large tumors that received suboptimal irradiation) had delayed tumor growth outside the radiosurgical treatment volume. The actuarial 2-year tumor growth control rate was 96%. Between 3 and 12 months after radiosurgery, three patients developed delayed neurological deficits that gradually improved, compatible with delayed radiation injury. Although extended follow-up monitoring over many years will be necessary to fully evaluate treatment, to date stereotactic radiosurgery has proved to be a relatively safe and effective therapy for selected patients with symptomatic meningiomas, including those who failed surgical resection. Radiosurgery was an effective primary treatment alternative for those patients whose advanced age, medical condition, or high-risk tumor location mitigated against surgical resection.
Language function following anterior temporal lobectomy
Authors: Hermann Bruce P. , Wyler Allen R. , Somes Grant
Published: May 2009

✓ The authors report the results of a prospective investigation that evaluated postoperative changes in language function after dominant (29 cases) or nondominant (35 cases) anterior temporal lobectomy for treatment of complex partial seizures. These patients received conservative resection of lateral temporal cortex but aggressive resection of medial temporal cortex, None of the patients underwent functional mapping of cortical language ability. All patients were assessed with a standardized aphasia battery (Multilingual Aphasia Examination) before and 6 months after surgery. Postoperatively, the dominant anterior temporal lobectomy group did not show any significant losses in language function compared to patients who underwent nondominant anterior temporal lobectomy. In addition, the dominant temporal lobectomy group showed significant postoperative improvement in complex receptive language comprehension compared to the nondominant group. These results suggest that patients with complex partial seizures of medial temporal lobe onset can undergo a conservative resection of lateral temporal cortex without language mapping. Such surgery carries little risk to language function and provides an excellent postoperative surgical outcome.
The standardized assessment of argyrophilic nucleolar organizer regions in meningeal tumors
Authors: Chin Lawrence S. , Hinton David R.
Published: May 2009

✓ Tissue markers of cellular proliferation have been recently utilized as prognostic indicators in tumors of the central nervous system. Nucleolar organizer regions represent transcriptionally active sites of ribosomal deoxyribonucleic acid (DNA) and can be identified by a simple argyrophilic technique. The authors describe a standardized approach to the assessment of these argyrophilic nucleolar organizer regions in meningeal tumors. Twenty-five meningiomas were classified histologically into benign, atypical, or malignant groups. In addition, two hemangiopericytomas and one leptomeningeal melanoma were examined. Appropriate sections were silver stained and argyrophilic nucleolar organizer regions were counted in 200 nuclei. The mean argyrophilic nucleolar organizer region count was statistically different (p < 0.001) between benign tumors (245 ± 156, 1.23/cell), atypical tumors (497 ± 135, 2.49/cell), and malignant tumors (921 ± 59, 4.61/cell). The count for recurrent meningiomas (544 ± 76) was also statistically different (p < 0.02) from non-recurrent tumors (329 ± 183). The standardized assessment of argyrophilic nucleolar organizer regions can be easily performed by any surgical pathology laboratory without specialized equipment and, in meningeal tumors, may be useful as an independent indicator of biological behavior.
Gangliosides: the relevance of current research to neurosurgery
Authors: Rodden Frank A. , Wiegandt Herbert , Bauer Bernard L.
Published: May 2009

✓ Gangliosides are complex glycolipids found on the outer surface of most cell membranes: they are particularly concentrated in tissues of the nervous system. Gangliosides form part of the immunological identity of mammalian cells and are involved in a variety of cell-surface phenomena such as cell-substrate binding and receptor functions. In tumorous tissue, the ganglioside composition is altered, sometimes in direct proportion to the degree of malignancy. The literature on the glycosphingolipid composition and immunology of intracranial tumors is reviewed.

Some gangliosides induce neuritogenesis and exhibit a trophic effect on nerve cells grown in vitro. In vivo, a particular ganglioside, GM1, reduces cerebral edema and accelerates recovery from injury (traumatic and ischemic) to the peripheral and central nervous systems of laboratory animals. Preliminary clinical studies have shown that treatment with gangliosides may have corresponding effects on lesions of the human peripheral nervous system. Gangliosides have not been tested in human subjects with brain injury.
Histological assessment of nerve lesions caused by epineurial electrode application in rat sciatic nerve
Authors: Girsch Werner , Koller Rupert , Gruber Helmut , Holle Jürgen , Liegl Christian , Losert Udo , Mayr Winfried , Thoma Herwig
Published: May 2009

✓ The left sciatic nerve of 36 rats was exposed and four ring-shaped stainless steel wire electrodes were sutured to the epineurium of each nerve in the same manner as performed clinically for “carousel stimulation” in man. The rats were sacrificed 10 days (Group 1), 3 weeks (Group 2), or 3 months (Group 3) after implantation. The electrodes were excised, the nerves were embedded in Epon, and semithin sections were obtained for histological and planimetric assessment of lesions caused by the epineurially sutured electrodes. The right sciatic nerves served as controls. The total area of neural tissue within the perineurium was determined at three levels: at the site of the electrodes, 8 mm proximal, and 8 mm distal. The area of neural tissue damaged by the surgical procedure was expressed as a percentage of the total area. In Group 1, nine of 12 nerves showed lesions ranging from 0.39% to 25.39% of the total area of neural tissue, in Group 2 eight of 11 sciatic nerves showed lesions ranging from 0.24% to 13.03% of the total area, and in Group 3 five of 12 nerves showed lesions ranging from 0.21% to 4.96% of the total area. The pathologically altered areas in Groups 2 and 3 exhibited distinct signs of nerve fiber regeneration. The reasons for the decrease in damage from Group 1 to Group 3 and the clinical implications of the results for long-term electrical stimulation are discussed.
Shunt nephritis
Authors: Rifkinson-Mann Stephanie , Rifkinson Nathan , Leong Terence
Published: May 2009

✓ The incidence of shunt nephritis has decreased over the past several years due to the increased use of ventriculoperitoneal (VP) shunts rather than the ventriculovascular systems for which this complication was originally reported in 1965. Despite this trend, the syndrome has been reported in cases of VP shunting and, for this reason, merit a renewed look. Shunt nephritis is thought to be secondary to immune complex formation and deposition in the kidney in response to Staphylococcus epidermidis. The diagnostic workup and management of this disease is discussed.
Optimal wound closure after tethered cord correction
Authors: Zide Barry M. , Epstein Fred J. , Wisoff Jeffrey
Published: May 2009

✓ A technique of wound closure following tethered cord correction is presented that significantly reduces the incidence of cerebrospinal fluid collections in the subcutaneous space. In over 60 cases, the described method of fascia and skin closure has lessened wound problems to a minimal level. Patient hospitalization time has also been greatly diminished.
Intraoperative protection of cranial nerves and perforating arteries by silicone rubber sheets
Authors: Shibuya Masato , Sugita Kenichiro , Kobayashi Shigeaki
Published: May 2009

✓ The authors describe a technique whereby, during microneurosurgery, vital structures are covered or wrapped with small pieces of silicone rubber sheeting to protect them from intraoperative injury. In this way, perforating arteries located behind a large aneurysm can be covered to avoid their inclusion within the blades of the clip, and the cranial nerves coursing around or through a tumor can be wrapped to protect them from injury by a suction or forceps. By insulating nerves and arteries, this silicone rubber sheet has the added advantage of protecting them from injury due to electrical current of bipolar forceps. The silicone rubber sheet described here is smoother, thinner, and lighter than a cotton pattie.
Postoperative radiotherapy in the management of spinal cord ependymoma
Authors: Whitaker Stephen J. , Bessell Eric M. , Ashley Sue E. , Bloom H. J. G. , Bell B. Anthony , Brada Michael
Published: May 2009

✓ Fifty-eight patients with histologically verified spinal cord ependymomas were treated at the Royal Marsden Hospital and Atkinson Morley's Hospital between 1950 and 1987. The median age in this series was 40 years (range 1 to 79 years) and the male:female ratio was 1.8:1. Ten patients had tumors in the cervical cord and 10 in the thoracic cord; 14 tumors involved the conus medullaris and 24 the cauda equina. Forty ependymomas were grade 1 and 13 were grades II to IV (in five patients there was insufficient material for grading). Eleven patients underwent biopsy only, 33 had partial or subtotal resection, and 14 had complete resection. Forty-three patients received postoperative radiotherapy. The median follow-up period was 70 months (range 3 to 408 months). Cause-specific survival rates were 74% and 68% at 5 and 10 years, respectively. On univariate analysis, age, histological grade, postoperative neurological function, and era of treatment were significant prognostic factors for survival. The histological grade was the only significant independent prognostic factor. The relative risk of death from ependymoma was 9.0 for patients with tumor grades II to IV compared to grade I (p < 0.005, 95% confidence interval 2.7 to 30).

The survival rates of patients following complete excision were significantly better compared to those after incomplete surgery (p < 0.025). The majority of completely resected neoplasms were low-grade cauda equina tumors. Despite incomplete surgery. 5- and 10-year progression-free survival rates following radical radiotherapy were both 59%, and cause-specific survival rates were 69% at 5 years and 62% at 10 years. This suggests that radiotherapy may achieve long-term tumor control in over half of those patients with residual spinal ependymoma.
Intraoperative ultrasonography: an important surgical adjunct for intramedullary tumors
Authors: Epstein Fred J. , Farmer Jean-Pierre , Schneider Steven J.
Published: May 2009

✓ The echographic characteristics of 186 suspected intramedullary spinal cord tumors were reviewed. Ultrasonography was found to be specific in distinguishing the tumor type, the extent of the lesion, and the presence and type of associated cysts. Ultrasonography greatly facilitates the selection of respective sites for the placement of a myelotomy, and for initiation of the resection. Additionally, this indispensable adjunct provides ongoing images that allow the preoperative plan to be precisely followed in a surgical field where anatomical landmarks are limited and the margin for error is minimal.
Altered gastric emptying in the head-injured patient: relationship to feeding intolerance
Authors: Ott Linda , Young Byron , Phillips Reneé , McClain Craig , Adams Linas , Dempsey Robert , Tibbs Phillip , Ryo U. Yun
Published: May 2009

✓ Most patients with moderate to severe head injury initially do not tolerate enteral feedings postinjury. This intolerance is more prolonged than that found in patients suffering other types of trauma. The authors prospectively evaluated 12 patients with moderate to severe head injury (Glasgow Coma Scale score between 4 and 10) throughout their hospitalization for liquid gastric emptying as a possible mechanism for intolerance to enteral feeding. During Week 1, the majority of patients displayed a delay in gastric emptying. Patients also displayed an abnormal biphasic response (gastric emptying faster than normal during the early stage but prolonged later). By Week 2, many patients still had delayed and abnormal biphasic responses to gastric emptying. By Week 3, an improvement was observed with the majority of patients exhibiting rapid gastric emptying, but delays and abnormal biphasic responses were still seen. Patients who initially had rapid or normal gastric emptying tolerated full-strength full-rate feedings significantly earlier compared with those who experienced delayed gastric emptying (8.5 ± 0.5 days vs. 13.7 ± 3.2 days, p < 0.001). All patients tolerated full-strength full-rate feedings by Day 16 postinjury (range 7 to 16 days) except the two patients who displayed delayed gastric emptying for prolonged periods of time (mean 25 days).

This is the first study to longitudinally evaluate gastric emptying following head injury. The authors suggest that patients with moderate to severe head injury often experience alterations in gastric emptying which may affect their ability to tolerate enteral feedings.
Unilateral facetectomy approach for lateral lumbar disc herniation
Authors: Garrido Eddy , Connaughton P. Noel
Published: May 2009

✓ Forty-one patients with herniated lumbar discs in a lateral location underwent unilateral complete facetectomy for removal of their disc herniation. The diagnosis was made by computerized tomography in all patients. The follow-up period varied between 4 and 60 months, with an average of 22.4 months. All patients underwent dynamic lumbar spine x-ray films with flexion and extension exposures at various times during their follow-up period.

The results were excellent in 35 patients, good in three, and poor in three. One patient suffered spinal instability postoperatively and required lumbar fusion because of back pain. Unilateral facetectomy gives an excellent view of the affected nerve root and the herniated disc, and the risk of spinal instability is very low.
Effect of intrathecal fibrinolysis on cerebrospinal fluid absorption after experimental subarachnoid hemorrhage
Authors: Brinker Thomas , Seifert Volker , Stolke Dietmar
Published: May 2009

✓ The effect of intrathecal fibrinolysis on cerebrospinal fluid (CSF) absorption was investigated after experimental subarachnoid hemorrhage (SAH). In 11 cats, SAH was induced by intracisternal application of 1 to 4 ml of fresh autologous blood. Thirty minutes after the experimental SAH, the CSF outflow resistance was found to be elevated from a median of 77 mm Hg/ml/min (range 41.3 to 109 mm Hg/ml/min) to a median of 580 mm Hg/ml/min (range 104 to 7000 mm Hg/ml/min). A logarithmic relationship could be demonstrated between the volume of subarachnoid blood and the elevation of the CSF outflow resistance. The intrathecal application of 2 mg of recombinant tissue plasminogen activator (rt-PA), which is a fibrinolytic substance suitable for lysis of subarachnoid blood clots in man, resulted in an almost total restoration of CSF absorption after experimental SAH. The CSF outflow resistance after SAH was lowered by application of rt-PA from a median of 1028.05 mm Hg/ml/min (range 394 to 7000 mm Hg/ml/min) to 79 mm Hg/ml/min (range 56.7 to 223 mm Hg/ml/min). It is concluded that the impairment of CSF absorption after SAH may play an important role in the pathogenesis of post-hemorrhagic vasospasm.
Long-time survival of a patient with glioblastoma and Turcot's syndrome
Authors: Rutz Hans Peter , de Tribolet Nicolas , Calmes Jean Marie , Chapuis Germain
Published: May 2009

✓ A rare case of Turcot's syndrome is reported in a long-time survivor of glioblastoma multiforme. The patient was treated for his tumor in 1976 with macroscopically complete surgical resection and radiotherapy consisting of 60 Gy to the tumor bed and 40 Gy to the whole brain. Five years later, in 1981, he developed adenocarcinoma of the colon Dukes Stage B which was successfully treated at another hospital by surgery alone. In 1990, he presented with multiple colon polyps and adenocarcinoma Dukes Stage A. For more than 15 years, the patient has been afflicted with cystic and conglobate acne. Possible mechanisms and treatment with 13-cis retinoic acid are discussed.
Lymphocytic adenohypophysitis presenting as infertility
Authors: McCutcheon Ian E. , Oldfield Edward H.
Published: May 2009

✓ The authors report a nulliparous patient presenting with infertility and hyperprolactinemia. She underwent transsphenoidal surgery after radiological investigation disclosed an enlarged pituitary gland which did not respond to bromocriptine therapy. The removed tissue had histological features consistent with adenohypophysitis including a diffuse lymphocytic infiltrate. The lymphocyte subsets present in the infiltrate were characterized by immunohistochemical methods to establish the contribution of different elements of the cellular immune response.

Lymphocytes bearing CD4 antigen (helper-inducer cells) were most prominent and appeared to bear the majority of the interleukin-2 receptor (expressed during lymphocytic activation) present in the pituitary gland. A few B lymphocytes were also observed. The location of the major histocompatibility antigen (classes I and II) and interleukin-2 receptor correlated with the lymphocytes and macrophages rather than with the stromal or parenchymal elements of the pituitary.

Lymphocytic adenohypophysitis is an unusual cause of pituitary enlargement which can mimic a pituitary tumor, and is sometimes associated with hyperprolactinemia. In women of child-bearing age, it almost always occurs during pregnancy or the postpartum stage. The autoimmune disorder reported here has not previously been associated with infertility nor has the lymphocytic infiltrate of the pituitary previously been analyzed in detail by modern immunological methods.
Isoflurane-induced attenuation of motor evoked potentials caused by electrical motor cortex stimulation during surgery
Authors: Calancie Blair , Klose K. John , Baier Sylvia , Green Barth A.
Published: May 2009

✓ Dysfunction of spinal motor conduction during surgical procedures may not be reflected by changes in somatosensory evoked potential waveforms. A method of monitoring that allows direct and continuous assessment of motor function within the central nervous system during surgery would be useful. This paper describes one such method utilizing noninvasive electric cortical stimulation to evoke muscle activity (the motor evoked potential, or MEP) during surgery. The effect of isoflurane (superimposed on a baseline of N2O/narcotic anesthesia) on MEP's in response to cortical stimulation is specifically examined.

Eight patients undergoing elective neurosurgical operations were included in the study. All patients received a background of general anesthesia and partial nondepolarizing neuromuscular blockade. The motor cortex was stimulated electrically via self-adhesive scalp electrodes. Electromyographic responses from multiple muscles were measured with subdermal electroencephalograph-type needle electrodes. Motor responses to stimulation were continually recorded on magnetic tape for off-line analysis. Once closing of the surgical incision was begun, a series of four to five stimuli of constant magnitude were applied to obtain “baseline” MEP responses. Patients were then ventilated with isoflurane for up to 8 minutes, during which time stimuli were continued every 15 to 20 seconds. Comparison was made of MEP responses for trials before, 1 minute after, and 5 minutes after the addition of isoflurane.

All patients demonstrated reproducible motor responses to cortical stimulation during surgery. Addition of isoflurane ((isoflurane)exp, ≤ 0.5%) to pre-existing anesthesia caused marked attenuation of MEP amplitudes in all patients within 5 minutes of its application, without affecting neuromuscular transmission as judged by direct peripheral nerve stimulation. It is concluded that: 1) monitoring motor system integrity and function with electric transcranial cortical stimulation during surgery is feasible when utilizing an N2O/narcotic anesthetic protocol; and 2) the quality of data obtained will likely suffer with the addition of isoflurane.
Developmental anterobasal temporal encephalocele and temporal lobe epilepsy
Authors: Leblanc Richard , Tampieri Donatella , Robitaille Yves , Olivier André , Andermann Frederick , Sherwin Alan
Published: May 2009

✓ The authors describe the association between an anterobasal temporal lobe encephalocele and medically intractable temporal lobe epilepsy in three patients treated successfully by surgery. Two men and one woman, aged 26 to 37 years (mean 31 years), had onset of complex automatism and generalized seizures in their second and fourth decades (mean age 22.7 years). They had been epileptic for 6 to 14 years (mean 8.3 years) before surgery. Preoperative electroencephalograms localized ictal epileptic activity to the left mesial temporal lobe in all cases, and neuropsychological testing revealed dominant temporal lobe dysfunction. Magnetic resonance (MR) imaging demonstrated an anteromedial basal temporal encephalocele extending into the pterygopalatine fossa through a bone defect at the base of the greater sphenoid wing in the region of the foramen rotundum and pterygoid process, a discrete center of embryonal chondrification. At surgery, the encephaloceles were found in front of the uncus, and an area of gliosis extended from the encephalocele to the amygdalohippocampal region. All patients have been seizure-free following anterior temporal resection and amygdalohippocampectomy including the encephalocele. These three cases delineate a condition of disordered embryogenesis wherein a developmental anterobasal temporal encephalocele acts as the substrate for temporal lobe epilepsy. This lesion may be diagnosed preoperatively with MR imaging and should be considered in the differential diagnosis of late-onset temporal lobe epilepsy.
Longitudinal time course of reversible and irreversible components of chronic cerebrovasospasm of the rabbit basilar artery
Authors: Vorkapic Peter , Bevan Rosemary D. , Bevan John A.
Published: May 2009

✓ Multiple injections of autologous blood were made around the basilar artery of rabbits through a silicone catheter placed into the prepontine cistern. The total blood injected was 3 ml/kg in aliquots of 0.5 to 0.8 ml over a 4-hour period. Control angiograms were obtained 7 days before this procedure. Groups of animals were examined by angiography on each of 9 days after the injections of blood. An angiogram was obtained 15 minutes after the first injection of blood, 20 seconds after the intra-arterial injection of a maximum dilating dose of papaverine. All surviving animals showed basilar artery narrowing, which was greatest 24 hours after the hemorrhage, when the vessel diameter was reduced to 54% of the control value. The narrowing then decreased to a reduction of about 30%, which was maintained throughout the rest of the study period. A papaverine-resistant component of narrowing was not seen until the 3rd day. It increased progressively to Day 9 when it represented 63% of the total. This model has a number of features that are reminiscent of human cerebrovasospasm, including the fact that there is an initial phase of narrowing that is completely reversed by an intra-arterially administered vasodilator, and a second phase beginning on Day 3 which exhibits a progressively increasing papaverine-resistant component.
Estramustine binding protein in human brain-tumor tissue
Authors: von Schoultz Eva , Bergenheim Tommy , Grankvist Kjell , Henriksson Roger
Published: May 2009

✓ Estramustine, an estradiol-17β and nornitrogen mustard complex, is used in the treatment of advanced prostatic carcinoma. A specific estramustine binding protein (EMBP) is important for its cytotoxic action, and the presence of EMBP has previously been demonstrated in rat and human prostatic cancer tissue. Significant levels of EMBP were detected by radioimmunoassay in human brain-tumor tissue. The EMBP concentrations (expressed as ng/mg protein) in 16 astrocytomas (mean 2.6 ng/mg, range 0.5 to 6.2 ng/mg) and seven meningiomas (mean 5.1 ng/mg, range 0.3 to 9.3 ng/mg) were significantly higher than that found in four samples of epileptic brain (mean 0.7 ng/mg, range 0.5 to 1 ng/mg) and 18 samples of normal brain (mean 0.5 ng/mg, range 0.2 to 1.0 ng/mg).

The uptake, metabolism, and antiproliferative effects of the prostatic anticancer agent estramustine have been previously demonstrated in cultured glioma cells. The presence of EMBP may suggest a selective binding and effectiveness in human brain-tumor tissue.
Radioimmunoassay of insulin-like growth factors in cyst fluid of central nervous system tumors
Authors: Glick Roberta P. , Unterman Terry G. , Hollis Robert
Published: May 2009

✓ Tumor cells are characterized by abnormalities in growth and metabolism, including the autocrine secretion of certain growth factors. The authors have previously shown the presence of insulin-like growth factor receptors in tumors of the central nervous system (CNS) and in this study examine whether CNS tumors are capable of autocrine secretion of insulin-like growth factors in situ. To investigate the production of insulin-like growth factors I and II by CNS tumors, the authors have developed specific radioimmunoassays for these growth factors. In situ production of insulin-like growth factors was studied by immunoassay of CNS tumor cyst fluid aspirated at the time of surgery from 12 cystic tumors: seven primary brain tumors, four metastatic tumors, and one spinal schwannoma. For immunoassay, cyst fluid was treated overnight with acetic acid, then insulin-like growth factors were separated from binding proteins by a refined solid-phase technique, then dried and reconstituted in immunoassay buffer. Normal human serum and cerebrospinal fluid served as controls. Insulin-like growth factor I was detected in all 12 tumors studied. In contrast, insulin-like growth factor II was detected only in three low-grade astrocytomas, the spinal schwannoma (which had the highest insulin-like growth factor II level of all tumors studied), and three metastatic lung cancers.

These results suggest that CNS tumors may be capable of autocrine production of insulin-like growth factors in situ. Furthermore, there appears to be a difference in the type of insulin-like growth factors produced by different types of CNS tumors. Preferential production of insulin-like growth factors may be an important marker of tumor differentiation and useful as a diagnostic tool.
Nucleolar organizer regions in various human brain tumors
Authors: Shiraishi Tetsuya , Tabuchi Kazuo , Mineta Toshihiro , Momozaki Nobuaki , Takagi Masashi
Published: May 2009

✓ Nucleolar organizer regions (NOR's) are loops of deoxyribonucleic acid (DNA) which transcribe to ribosomal ribonucleic acid (RNA) by RNA polymerase I. They possess vital significance in the ultimate synthesis of cellular proteins. A silver colloid staining technique for demonstration of NOR-associated proteins (Ag-NOR's) was applied to paraffin-embedded sections from 128 varied brain tumors and to chromosomal preparations from cultured brain-tumor cells. There was a statistically significant difference in the mean number of Ag-NOR's per nucleus between low-grade tumors (1.98/nucleus) and high-grade tumors (2.95/nucleus). It is suggested that the mean number of Ag-NOR's may represent the proliferative potential of brain tumors. Furthermore, high-grade tumors usually showed relatively large Ag-NOR's in a scattered distribution. In chromosomal preparations, the cultured cells displayed five to 12 Ag-NOR's on acrocentric chromosomes. Five of eight cell lines examined demonstrated ectopic Ag-NOR's.

This simple staining technique can be easily applied to routinely processed paraffin-embedded sections and will become a useful tool for quick estimation of the proliferative potential of human brain tumors.
Fatal rupture of the intracranial carotid artery during transluminal angioplasty for vasospasm induced by subarachnoid hemorrhage
Authors: Linskey Mark E. , Horton Joseph A. , Rao Gutti R. , Yonas Howard
Published: May 2009

✓ The authors report the clinical course, radiographic findings, and gross and microscopic pathology of a patient with fatal rupture of the supraclinoid segment of the left internal carotid artery during transluminal angioplasty for subarachnoid hemorrhage-induced vasospasm. The rupture most likely resulted from a small portion of aneurysm neck which remained unclipped, thereby leaving an area of structural weakness in the arterial wall at the site of clipping. The area of structural weakness predisposed the artery to rupture upon the addition of transmural pressure induced by balloon inflation during transluminal angioplasty. Caution is advised when performing transluminal angioplasty in the region of aneurysm clipping since the vessel lumen “recreated” during the clipping procedure may contain some residual and structurally incomplete aneurysm neck in the vessel wall.
Anterolateral transthoracic transvertebral resection of an intramedullary spinal arteriovenous malformation
Authors: Williams Fred C. , Zabramski Joseph M. , Spetzler Robert F. , Rekate Harold L.
Published: May 2009

✓ The case is reported of a 16-year-old girl with an anterior thoracic spinal cord arteriovenous malformation (AVM) who presented with subarachnoid hemorrhage and sudden change in lower-extremity strength. Spinal angiography revealed a Type II (glomus) intramedullary AVM at the T7–8 level fed by multiple branches of the anterior spinal artery. The AVM was successfully resected using an anterolateral transthoracic approach. The details of this approach and its use for surgery of anterior thoracic spine lesions are described.
A micromanipulator for precise control of a brain retractor
Authors: Hasegawa Takeshi , Yamano Kiyotoshi , Miyamori Tadao , Hamada Yoshitaka
Published: May 2009

✓ A new microsurgical device for delicate brain retraction is described. The device, a micromanipulator with a holder for a brain spatula fixed at the end of a self-retaining retractor arm, allows smooth, steady, fine displacement of the retractor tip (“minimal sliding retraction”), operated by the surgeon's two fingers. This has proved to be a useful and safe method of retraction for critical brain structures such as blood vessels, cranial nerves and aneurysm domes in deep microsurgical fields.
Transesophageal echocardiography: a simple method for monitoring the patency of ventriculoatrial shunts
Authors: Calliauw Luc , Vandenbogaerde Johan , Kalala Okito , Caemaert Jacques , Martens Frédéric , Vandekerckhove Tom
Published: May 2009

✓ A new method for evaluating the patency of a ventriculoatrial shunt is described, and early experience with it is reported. Transesophageal echocardiography can demonstrate a cerebrospinal fluid leak in the right atrium through the atrial tip of a shunting device. This capability was an incidental discovery, and since then the accuracy of the technique in evaluating the patency of a ventriculoatrial shunt has been prospectively studied in 20 observations of 16 patients. The method proved to be accurate in 90% to 100% of cases. It is concluded that transesophageal echocardiography offers a rapid and accurate assessment of ventriculoatrial shunt function, is well tolerated, and is easy to perform.
Electrothrombosis of saccular aneurysms via endovascular approach
Authors: Guglielmi Guido , Viñuela Fernando , Dion Jacques , Duckwiler Gary
Published: May 2009

✓ Fifteen patients with high-risk intracranial saccular aneurysms were treated using electrolytically detachable coils introduced via an endovascular approach. The patients ranged in age from 21 to 69 years. The most frequent clinical presentation was subarachnoid hemorrhage (eight cases). Considerable thrombosis of the aneurysm (70% to 100%) was achieved in all 15 patients, and preservation of the parent artery was obtained in 14. Although temporary neurological deterioration due to the technique was recorded in one patient, no permanent neurological deficit was observed in this series and there were no deaths. It is believed that this new technology is a viable alternative in the management of patients with high-risk intracranial saccular aneurysms. It may also play an important role in the occlusion of aneurysms in the acute phase of subarachnoid hemorrhage.