bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of magnetic resonance neurography in the evaluation of patients with peripheral nerve pathology
Authors: Filler Aaron G. , Kliot Michel , Howe Franklyn A. , Hayes Cecil E. , Saunders Dawn E. , Goodkin Robert , Bell B. Anthony , Winn H. Richard , Griffiths John R. , Tsuruda Jay S.
Published: June 2009

✓ Currently, diagnosis and management of disorders involving nerves are generally undertaken without images of the nerves themselves. The authors evaluated whether direct nerve images obtained using the new technique of magnetic resonance (MR) neurography could be used to make clinically important diagnostic distinctions that cannot be readily accomplished using existing methods.

The authors obtained T2-weighted fast spin—echo fat-suppressed (chemical shift selection or inversion recovery) and T1-weighted images with planes parallel or transverse to the long axis of nerves using standard or phased-array coils in healthy volunteers and referred patients in 242 sessions.

Longitudinal and cross-sectional fascicular images readily distinguished perineural from intraneural masses, thus predicting both resectability and requirement for intraoperative electrophysiological monitoring. Fascicle pattern and longitudinal anatomy firmly identified nerves and thus improved the safety of image-guided procedures. In severe trauma, MR neurography identified nerve discontinuity at the fascicular level preoperatively, thus verifying the need for surgical repair. Direct images readily demonstrated increased diameter in injured nerves and showed the linear extent and time course of image hyperintensity associated with nerve injury. These findings confirm and precisely localize focal nerve compressions, thus avoiding some exploratory surgery and allowing for smaller targeted exposures when surgery is indicated.

Direct nerve imaging can demonstrate nerve continuity, distinguish intraneural from perineural masses, and localize nerve compressions prior to surgical exploration. Magnetic resonance neurography can add clinically useful diagnostic information in many situations in which physical examinations, electrodiagnostic tests, and existing image techniques are inconclusive.
Neural connection between the ventral portion of the lumbar intervertebral disc and the groin skin
Authors: Takahashi Yuzuru , Morinaga Tatsuo , Nakamura Shin-Ichiro , Suseki Kaoru , Takahashi Kazuhisa , Nakajima Yoshio
Published: June 2009

✓ This study was designed to investigate neural mechanisms of referred pain in lumbar intervertebral disc lesions. Patients with a degenerative disc in lower lumbar segments occasionally complain of groin pain, which cannot be explained anatomically as having a radicular origin.

In rats pretreated with intravenous application of Evans blue dye, the dye extravasation appeared in the groin skin after application of capsaicin to the ventral portion of the L5–6 intervertebral disc. This response occurred even in rats with a sectioned L-5 spinal nerve and sympathetic trunks, but did not occur in rats with a sectioned genitofemoral nerve. Capsaicin topically applied to the sciatic nerve did not cause dye extravasation in the hindpaw. Therefore, groin dye extravasation was not due to a direct effect of capsaicin but, rather, presumably was caused by an “antidromic axon reflex” of dichotomizing C fibers or to a segmental sympathetic reflex causing vascular permeability.

The present results indicate that the ventral portion of the lumbar discs is neurally connected to the groin skin via the upper (L-2) lumbar spinal nerves in rats. Groin pain coincident with low-back pain may be explained as referred pain, indicating that a lesion is present in the ventral portion of the lumbar intervertebral disc space.
Thrombin-soaked gelatin sponge and brain edema in rats
Authors: Colon Gary P. , Lee Kevin R. , Keep Richard F. , Chenevert Thomas L. , Betz A. Lorris , Hoff Julian T.
Published: June 2009

✓ Previous work from this laboratory has shown that injection of thrombin into rat basal ganglia causes brain edema. This study investigates the effect on rat brain of thrombin-soaked gelatin sponge (used for intraoperative hemostasis in clinical situations) at a concentration similar to that used in humans. Three models were developed to evaluate this effect. In the first model, a gelatin sponge soaked with vehicle or thrombin (100 U/cm3) was placed on the intact pia of the right frontal lobe in rats without cortical lesions. In the second model, frontal cortex was excised (3 mm3) and the exposed brain was cauterized with electrocoagulation. Gelatin sponge was soaked with vehicle or thrombin (1000, 100, 10, or 1 U/cm3) and placed in the lesion site. In the third model, hirudin, a specific thrombin antagonist, was added to the thrombin-soaked gelatin sponge and placed in a similar cortical lesion to determine if the observed effects were specific to thrombin. The dose-response range for thrombin was determined qualitatively by magnetic resonance (MR) imaging and quantitatively by brain edema formation 24 hours after exposure. We found no edema in the cortically intact rats. The rats given cortical lesions developed significant edema when subjected to 1000, 100, and 10 U/cm3 thrombin as seen on MR imaging and at 100 and 10 U/cm3 thrombin as revealed by wet/dry weight and ion studies of brain tissue. Topical hirudin prevented thrombin-induced edema. It is concluded that thrombin-soaked gelatin sponges cause or enhance significant brain edema in rats at concentrations typically used for human neurosurgery.
Arteriovenous fistula as a complication of C1–2 transarticular screw fixation
Authors: Coric Domagoj , Branch Charles L. , Wilson John A. , Robinson James C.
Published: June 2009

✓ A case is reported of a vertebral artery-to-epidural venous plexus fistula as a complication of posterior atlantoaxial facet screw fixation. The use of transarticular screws to stabilize the C1–2 joint has become an increasingly popular fixation technique, most notably for atlantoaxial instability due to trauma or rheumatoid disease. Despite the fact that this approach is technically challenging, there have been few reports of complications associated with C1–2 transarticular fixation. Although damage to the vertebral artery is a documented hazard of transarticular fixation at this level, a symptomatic arteriovenous fistula resulting from the procedure has not been described previously. The etiology, presentation, and treatment of this unusual complication are discussed.
Spinal extradural meningeal cyst
Authors: Uemura Kazuya , Yoshizawa Takashi , Matsumura Akira , Asakawa Hiroyuki , Nakamagoe Kiyotaka , Nose Tadao
Published: June 2009

✓ The case of a 30-year-old man with a spinal extradural meningeal cyst in the thoracolumbar region is reported. Operative findings revealed a dural defect that allowed communication between the extradural cyst cavity and the subarachnoid space. Application of the Valsalva maneuver made the cerebrospinal fluid flow into the cyst cavity; however, reverse flow did not occur. These findings indicate that a valvelike mechanism developed in the enlarging cyst. Surgical resection of the cyst wall and closure of the dural defect provided a favorable result.
A new instrument for improved accuracy of stereotactic depth electrode placement
Authors: Ashpole Richard D. , Fabinyi Gavin C. A. , Vosmansky Milos
Published: June 2009

✓ A disadvantage of stereotactic placement of flexible depth electrodes is the risk of inaccurate positioning as a result of electrode movement when the introducer is withdrawn. A simple device that virtually eliminates this error is described.
Posterior transpetrosal approach to aneurysms of the basilar trunk and vertebrobasilar junction
Authors: Seifert Volker , Stolke Dietmar
Published: June 2009

✓ Aneurysms of the basilar trunk and vertebrobasilar junction represent an exceptional challenge to the neurosurgeon. Surgical access to these deep and confined lesions is hampered by the direct proximity of highly vulnerable neural structures such as the brainstem and cranial nerves, as well as by the structure of the petrous bone, which blocks direct surgical approach to these aneurysms. A number of surgical tactics consisting of different supra- and infratentorial approaches have been applied over the years to gain access to these treacherous lesions. Only recently have lateral approaches, such as the anterior transpetrosal, the retrolabyrinthine—transsigmoidal, and the combined supra/infratentorial—posterior transpetrosal approaches, directed through parts of the petrous bone, been reported for surgery of basilar trunk and vertebrobasilar junction aneurysms. Because detailed reports of direct operative intervention using the transpetrosal route for these rare and difficult lesions are scarce, the authors present their surgical experiences in nine patients with basilar trunk and vertebrobasilar junction aneurysms, in whom they operated via the supra/infratentorial—posterior transpetrosal approach. In eight patients, including one with a giant partially thrombosed basilar trunk aneurysm, direct clipping of the aneurysm via the transpetrosal route was possible. In one patient with a giant vertebrobasilar junction aneurysm, the completely calcified aneurysm sac was resected after occlusion of the vertebral artery. In total, one patient died and another experienced postoperative accentuation of preexisting cranial nerve deficits. Two patients had transient cerebrospinal fluid leakage, and the postoperative course was uneventful in the remaining seven. Postoperative angiography demonstrated complete aneurysm clipping in eight patients and relief of preoperative brainstem compression in the patient with the giant vertebrobasilar junction aneurysm. It is concluded that the supra/infratentorial—posterior transpetrosal approach allows excellent access to the basilar artery trunk and vertebrobasilar junction and can be considered the approach of choice to selected aneurysms located in this area.
Terson's syndrome in spontaneous subarachnoid hemorrhage: a prospective study in 60 consecutive patients
Authors: Pfausler Bettina , Belcl Regina , Metzler Regina , Mohsenipour Iradj , Schmutzhard Erich
Published: June 2009

✓ Sixty consecutive patients with spontaneous subarachnoid hemorrhage (SAH) were prospectively studied by means of indirect funduscopy to address the question of incidence and prognostic implications of Terson's syndrome (TS) after SAH. Terson's syndrome was diagnosed in 10 (16.7%) of 60 patients and was associated with subarachnoid rebleeding in seven of 10. No correlation was found between anatomical localization of the ruptured aneurysm and TS laterality. Case fatality was nine (90%) of 10 in patients with TS compared to five (10%) of 50 in non-TS patients. It is concluded that TS is not infrequent (16.7%) in spontaneous SAH and has a poor prognosis, often heralding subarachnoid rebleeding.
Superselective intraarterial papaverine administration: effect on regional cerebral blood flow in patients with arteriovenous malformations
Authors: Fogarty-Mack Patricia , Pile-Spellman John , Hacein-Bey Lotfi , Ostapkovich Noeleen , Joshi Shailendra , Vulliemoz Yvonne , Young William L.
Published: June 2009

✓ In this study the authors determined the effect of papaverine on regional cerebral blood flow (rCBF) in the angiographically normal arteriolar beds of patients with arteriovenous malformations (AVMs) who underwent transfemoral superselective angiography.

Middle cerebral artery (MCA) branch vessels were catheterized during 10 procedures performed in nine patients. The mean (± standard deviation) largest AVM diameter was 4.4 ± 1 cm. Regional CBF was measured by recording the washout of a bolus of xenon-133 injected through the microcatheter. In a dose-ranging study, rCBF and MCA pressure in two patients were repeatedly measured after 3-minute infusions of papaverine at 0.07, 0.7, and 7 mg/minute. In a single-dose study, an additional eight patients received only the highest dose of papaverine administered over a 3-minute period. In the dose-ranging study, CBF increased from baseline in a dose-dependent fashion. In the single-dose study, papaverine increased rCBF 103%, from 48 ± 11 to 95 ± 23 ml/100 g/minute at an MCA pressure of 55 ± 23 mm Hg. Increase in rCBF was linearly related (y = 2.2x − 17, r2= 0.84; p = 0.001) to baseline MCA pressure (range 22–84 mm Hg).

Papaverine increases rCBF in a direct proportion to baseline MCA pressure, even at low baseline pressures. Selective infusion of vasodilators should be investigated in acute cerebral hypotension to facilitate either primary or collateral recruitment of CBF by aiding spontaneous autoregulatory vasodilation. In addition, rCBF monitoring may be useful in determining the most effective intraarterial dose of papaverine while minimizing complications due to hyperemia.
Hospital resource utilization in the treatment of cerebral aneurysms
Authors: Yundt Kent D. , Dacey Ralph G. , Diringer Michael N.
Published: June 2009

✓ The authors reviewed clinical and financial data for all patients treated for nontraumatic subarachnoid hemorrhage (SAH) and unruptured cerebral aneurysms at their institution between June 1993 and December 1994. This study sought to identify specific areas of high resource utilization that may be amenable to reduction of expenditures without compromising quality of care. Detailed hospital financial data were correlated with clinical grade and course. Areas of high resource use were identified based on patient charges and category-specific loaded hospital cost. Patients were divided into four groups: Group 1, surgically treated unruptured aneurysms (28 patients); Group 2, acute SAH (42 patients); Group 3, SAH with vasospasm (32 patients); and Group 4, SAH with negative angiogram (10 patients). Total cost per patient (mean ± standard deviation in thousands of U.S. dollars) was highest for Group 3 (38.4 ± 21.3; vs. Group 1, 12.7 ± 8.8; Group 2, 22.6 ± 20.9; and Group 4, 25.0 ± 33.5) and correlated with hospital length of stay, Hunt and Hess grade, and Fisher grade. Areas of highest hospital cost were not always reflected in patient charges. The three areas of highest cost accounted for 48.5% of the total cost and were: 1) intensive care unit (ICU) room (Group 1, 2.5 ± 3.5; Group 2, 7.0 ± 9.2; Group 3, 11.0 ± 7.8; and Group 4, 7.9 ± 14.1); 2) arteriography (Group 1, 1.7 ± 1.2; Group 2, 2.1 ± 1.5; Group 3, 4.1 ± 2.1; and Group 4, 2.2 ± 0.7); and 3) ICU medicosurgical supplies (Group 1, 1.7 ± 0.8; Group 2, 2.0 ± 1.5; Group 3, 3.7 ± 1.7; and Group 4, 2.0 ± 3.0). It is concluded that cost containment strategies should be based on cost rather than charge and novel approaches will be required to reduce the cost of treating patients with SAH. Such approaches might include preventing vasospasm, reducing ICU stay, selective use of arteriography, and reducing the cost of supplies.
Ventriculostomy infections: the effect of monitoring duration and catheter exchange in 584 patients
Authors: Holloway Kathryn L. , Barnes Tom , Choi Sung , Bullock Ross , Marshall Lawrence F. , Eisenberg Howard M. , Jane John A. , Ward John D. , Young Harold F. , Marmarou Anthony
Published: June 2009

✓ The investigators undertook a retrospective analysis of ventriculostomy infections to evaluate their relationship to monitoring duration and prophylactic catheter exchange. In 1984, the results of an epidemiological study of ventriculostomy-related infection were published. One of the conclusions of the paper was that the incidence of ventriculostomy-related infections rose after 5 days of monitoring. This led to the recommendation that catheters be prophylactically changed at 5-day intervals if prolonged monitoring was required. A recent randomized prospective study on central venous catheters showed no reduction in infection with prophylactic catheter exchanges. This has led the authors to reexamine their experience with ventriculostomy infections. Data on 584 severely head injured patients with ventriculostomies were prospectively collected in two data banks, The Traumatic Coma Data Bank and The Medical College of Virginia Neurocore Data Bank. These data were retrospectively analyzed for factors associated with ventriculostomy related infections. It was found that there is a relationship of ventriculitis to monitoring duration but it is not simple or linear. There is a rising risk of infection over the first 10 days, but infection then becomes very unlikely despite a population that continues to be at risk. Patients in whom catheters were replaced prior to 5 days did not have a lower infection rate than those whose catheters were exchanged at more than 5-day intervals. Based on these data, it is recommended that ventriculostomy catheters for intracranial pressure monitoring be removed as quickly as possible, and in circumstances in which prolonged monitoring is required, there appears to be no benefit from catheter exchange.
Experience with use of extended length peritoneal shunt catheters
Authors: Couldwell William T. , Lemay Daniel R. , McComb J. Gordon
Published: June 2009

✓ The placement of a ventriculoperitoneal (VP) shunt is the current treatment of choice for diversion of cerebrospinal fluid associated with hydrocephalus. Although there are a host of reported potential abdominal complications related to the procedure, they are notably uncommon. The authors report their experience with the primary insertion of an extended length open-ended peritoneal tubing (120 cm) undertaken expressly to avoid the need for a lengthening procedure because of growth of the patient. In a review of new insertions of VP shunts using the extended length tubing over a 14-year period at Childrens Hospital of Los Angeles, a total of 998 shunts were placed in 952 patients, with a mean follow-up period of 6.7 years. The patients experienced a total of 52 distal shunt revisions for a variety of malfunction etiologies. In patients ranging in age from premature neonate to 20 years, there was no increase in the distal complication rate, and specifically no complications were experienced that were directly related to the use of the extended length tubing. The authors conclude that the use of an extended length peritoneal shunt catheter is not associated with an increase in complications and eliminates the need to lengthen the peritoneal catheter for growth of the patient.
Indications and results of combined anterior—posterior approaches for spine tumor surgery
Authors: Sundaresan Narayan , Steinberger Alfred A. , Moore Frank , Sachdev Ved Parkash , Krol George , Hough Laura , Kelliher Kevin
Published: June 2009

✓ Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5-year period (1989–1993) at a single institution. Major primary sites of tumor included breast (14 cases), chordoma (14 cases), lung (12 cases), kidney (11 cases), sarcoma (13 cases), plasmacytoma (10 cases), and others (36 cases). Prior to surgery, 55 patients (50%) had received prior treatment. Forty-eight patients (44%) were nonambulatory, and severe paraparesis was present in 20 patients. Fifty-three patients (48%) underwent combined anterior—posterior resection and instrumentation, 33 (30%) underwent anterior resection with instrumentation, 18 (16%) underwent anterior or posterior resection alone, and the remaining six patients (5%) underwent posterior resection and instrumentation. Major indications for anterior—posterior resection included three-column involvement, high-grade instability, involvement of contiguous vertebral bodies, and solitary metastases. Postoperatively, 90 patients improved neurologically. The overall median survival was 16 months, with 46% of patients surviving 2 years. Fifty-three patients (48%) suffered postoperative complications. Despite the high incidence of complications, the majority of patients reported improvement in their quality of life at follow-up review. Our findings suggest that half of all patients with spinal malignancies require combined anterior—posterior surgery for adequate tumor removal and stabilization.
Chronic intrathecal delivery of baclofen by a programmable pump for the treatment of severe spasticity
Authors: Ordia Joe I. , Fischer Edward , Adamski Ellen , Spatz Edward L.
Published: June 2009

✓ The aim of this study was to determine the efficacy, safety, and cost-effectiveness of intrathecal baclofen delivered by a programmable pump for the chronic treatment of severe spasticity. Sixty-six patients with severe spasticity of spinal cord origin that was refractory to oral baclofen or who experienced intolerable side effects with this form of the drug were screened. The first nine participated in a double-blinded, randomized, placebo (normal saline)-controlled trial to determine response to a bolus dose of intrathecal baclofen. Subsequent patients were enrolled in an open-label treatment protocol without a placebo trial. All passed the screening, and the pump was implanted in 59 patients. Spasticity scores and medical costs before and after surgery were analyzed.

In all patients, the mean Ashworth score for rigidity decreased from 4.3 preoperatively to 1.4 (p < 0.0005) with use of intrathecal baclofen. The spasm frequency score decreased from a mean of 3.6 to 0.5 (p < 0.0005). Activities of daily living, sleep, and skin integrity improved, and pain was eradicated in some. Constipation occurred in six patients. A reduction in dosage was necessitated by muscular hypotonia in three ambulatory patients, areflexic bladder and urinary retention in three others, and nausea, dizziness, and drowsiness in one. Catheter-related problems occurred 19 times in 15 patients. One pump was explanted because of infection in the pump pocket, and one was removed after it eroded through the skin. There were no pump failures. The use of intrathecal baclofen resulted in a decrease in the average length of subsequent hospitalizations. It is concluded that intrathecal baclofen delivered by an implanted programmable pump is a safe, effective, and cost-efficient method for treatment of severe intractable spinal spasticity.
Activation of the complement cascade and increase of clusterin in the brain following a cortical contusion in the adult rat
Authors: Bellander Bo-Michael , Holst Hans von , Fredman Pam , Svensson Mikael
Published: June 2009

✓ The aim of the present study was to examine the glial cell response and the possible involvement of the complement cascade following a cerebral cortical contusion. The lesion was produced using a standardized weight-drop technique in adult rats. The blood-brain barrier was damaged, as demonstrated by a decrease of immunoreactivity for a tight junction protein normally expressed by endothelial cells of small vessels in the central nervous system. Increased immunoreactivity for microglial (OX42) and astroglial cells (glial fibrillary acidic protein), as well as macrophages expressing ED1-immunoreactivity (IR) were found in the vicinity of the lesion at all postoperative survival times (2–14 days).

In the present study complement factor C3d- and C9-IR was found around the lesion, indicating that activation of the complement cascade had taken place. Furthermore, immunoreactivity for the putative complement inhibitor clusterin (sulfated glycoprotein-2) was found in some of the injured neurons. The contralateral hemisphere showed no evidence of the reaction found in the ipsilateral hemisphere. The balance between complement activation and complement inhibitors may have an impact on the degenerative components in the brain following traumatic injury and in particular on the events leading to nerve cell death.
Blood-brain barrier breach following cortical contusion in the rat
Authors: Baldwin Stanley A. , Fugaccia Isabella , Brown David R. , Brown Laura V. , Scheff Stephen W.
Published: June 2009

✓ Adult Fisher 344 rats were subjected to a unilateral impact to the dorsal cortex above the hippocampus at 3.5 m/second, resulting in a 2-mm cortical depression. This caused severe cortical damage and neuronal loss in hippocampus subfields CA1, CA3, and hilus. Breakdown of the blood-brain barrier (BBB) was assessed by injecting the protein horseradish peroxidase (HRP) 5 minutes prior to or at various times after injury (5 minutes, 1, 3, 6, and 12 hours, 1, 2, 5, and 10 days). Animals were killed 1 hour after HRP injection and brain sections were reacted with diaminobenzidine to visualize extravascular accumulation of the protein. Maximum staining occurred in animals injected with HRP 5 minutes prior to or 5 minutes after cortical contusion. Staining at these time points was observed in the ipsilateral cortex of the impact area and areas adjacent to it, as well as in the ipsilateral hippocampus. Some modest staining occurred in the dorsal contralateral cortex near the superior sagittal sinus. Cortical HRP staining gradually decreased at increasing time intervals postinjury. By 10 days, no HRP staining was observed in any area of the brain. In the ipsilateral hippocampus, HRP staining was absent by 3 hours postinjury and remained so at the 6- and 12-hour time points. Surprisingly, HRP staining was again observed in the ipsilateral hippocampus 1 and 2 days after cortical contusion, indicating a biphasic opening of the BBB following head trauma and a possible second wave of secondary brain damage days after the contusion injury. These data indicate that regions not initially destroyed by cortical impact, but evidencing BBB breach, may be accessible to neurotrophic factors administered intravenously both immediately and days after brain trauma.
The Q10 ratio for basal cerebral metabolic rate for oxygen in rats
Authors: Klementavicius Richard , Nemoto Edwin M. , Yonas Howard
Published: June 2009

✓ Previously the authors showed that hypothermia exerts a greater effect on the cerebral metabolic rate for oxygen (CMRO2) that is associated with the maintenance of cellular viability, or “basal” CMRO2, than on electroencephalogram (EEG)-associated CMRO2 or “functional” CMRO2. On the basis of their findings, the authors hypothesized that the ratio of CMRO2 over a 10°C temperature range (Q10) for basal CMRO2 was greater than that for functional and total CMRO2. They tested their hypothesis by determining the Q10 for basal CMRO2 from 38°C to 28°C. They measured whole-brain cerebral blood flow (CBF) and CMRO2 in six rats during progressive hypothermia at a brain temperature of 38°C and, after induction of an isoelectric EEG signal (50 µV/cm) with thiopental sodium, they repeated the measurements at 38°C, 34°C, 30°C, and 28°C. In a control group (five rats), six sequential measurements of CBF and CMRO2 were made while the animals were anesthetized by 0.5% isoflurane/70% N2O/30% O2 at a brain temperature of 38°C over a time span equivalent to the hypothermic group, that is, approximately 3 hours. The Q10 for basal CMRO2 calculated over 38°C to 28°C was 5.2 ± 0.92. However, the decrease in basal CMRO2 between 38°C and 28°C was nonlinear on a log plot, revealing a two-component response: a high temperature sensitivity component between 38°C and 30°C with a Q10 of 12.1, and a lower temperature sensitivity component between 30°C and 28°C with a Q10 of 2.8. The combined overall Q10 for basal CMRO2 between 38° and 28°C was 5.2. The energy-requiring processes associated with these high and low temperature sensitivity components of basal CMRO2 have yet to be identified.
Reconstruction of the posterior inferior cerebellar artery in the treatment of giant aneurysms
Authors: Hamada Jun-Ichiro , Nagahiro Shinji , Mimata Chikara , Kaku Takayuki , Ushio Yukitaka
Published: June 2009

✓ Two techniques of revascularizing the posterior inferior cerebellar artery (PICA) during aneurysm surgery are presented. One involves transposition of the PICA to the vertebral artery proximal to the aneurysm using a superior temporal artery (STA) as a graft. This is used in cases in which the PICA has branched off from the wall of the giant vertebral artery aneurysm. The other technique involves end-to-end anastomosis of the PICA after excision of a giant distal PICA aneurysm located at the cranial loop near the roof of the fourth ventricle. The reconstructions of the PICA described here are surgical procedures designed to preserve normal blood flow in the PICA in patients treated for giant aneurysms involving that artery.
Aneurysm formation and rupture at the site of anastomosis following bypass surgery
Authors: Sasaki Tatsuya , Kodama Namio , Itokawa Hiroshi
Published: June 2009

✓ Four years after undergoing a superficial temporal artery—middle cerebral artery bypass procedure, this patient presented with a ruptured aneurysm at the anastomosis site. The ruptured aneurysm caused subarachnoid and intracerebral hemorrhages and was treated by surgically clipping its neck. Characteristics of the aneurysm included: 1) a relatively large size (8 × 6 × 6 mm); 2) a thickened wall; 3) a location apart from the suture line; 4) a projection in a direction consistent with hemodynamic stress; and 5) a time interval from bypass surgery to rupture that lasted 4 years. These features, along with the well-known fact that hemodynamic stress can cause aneurysms, led the authors to believe that this aneurysm was a true one. The authors present a case of this unusual complication following bypass surgery and provide a brief review of the literature.
Idiopathic orbital inflammation with intracranial extension
Authors: De Jesús Orlando , Inserni Jaime A. , Gonzalez Anarda , Colón Lillian E.
Published: June 2009

✓ Idiopathic orbital inflammation or orbital pseudotumor with intracranial extension is a rare condition. It consists of a nonspecific infiltrate of the fatty tissue of the orbit that extends through one or more foramina into the adjacent intracranial tissue. The lesion mimics an infectious or neoplastic lesion. The authors present a case involving the youngest patient yet reported, with the broadest intracranial extension. Only 17 previous cases have been reported. The principal symptoms include decreased visual acuity and proptosis. Extension commonly develops through the superior orbital fissure into the middle cranial fossa and the cavernous sinus. The initial treatment is a regimen of high-dose steroids, with radiotherapy given in unresponsive cases.
Bridged craniotomy for stable fixation of a bone flap
Authors: Ochiai Chikayuki , Okuhata Soshi , Yoshimoto Yuhei , Nagai Masakatsu
Published: June 2009

✓ Postoperative depression of the bone flap is a common and bothersome problem in craniotomies. In this paper, a simple technique to avoid this deformity is described. The key to this technique is to leave uncut a part of each osteotomy approximately 5 mm in width as a “bridge” to the bone flap, which is then subsequently cut with the aid of a chisel. This technique provides stable fixation of the bone flap and satisfactory cosmetic results with little additional operating time.
Treatment of traumatic spondylolisthesis of the axis with nonrigid immobilization: a review of 64 cases
Authors: Coric Domagoj , Wilson John A. , Kelly David L.
Published: June 2009

✓ Current treatment regimens for hangman's fracture, or traumatic spondylolisthesis of the axis, emphasize rigid immobilization using a halo orthosis. A retrospective study was undertaken to assess the safety and efficacy of nonrigid immobilization in the treatment of these fractures.

Records of 64 patients with hangman's fracture treated over a 19-year period (1975–1994) at one institution were reviewed. Thirty-nine of these patients presented with a displacement of C-2 onto C-3 measuring less than 6 mm and no contiguous cervical fractures. All these patients were treated with nonrigid immobilization, consisting primarily of a Philadelphia hard collar worn for 10 to 14 weeks; all showed stable fracture healing on follow-up flexion—extension radiographs. None of the patients experienced neurological sequelae or significant disability at follow-up review.

The results of this series indicate that the majority of patients with hangman's fractures, including all patients with displacement measuring less than 6 mm and no contiguous fractures, may be treated successfully with nonrigid immobilization. This management regimen avoids the increased morbidity and cost associated with rigid immobilization using a halo orthosis.
Impact of urodynamic studies on the surgical management of spinal cord tethering
Authors: Vernet Olivier , Farmer Jean-Pierre , Houle Anne-Marie , Montes José L.
Published: June 2009

✓ To determine the usefulness of urodynamic studies in the management of children with a suspected tethered spinal cord, the authors retrospectively reviewed case records of 25 patients evaluated both pre- and postoperatively using this diagnostic adjunct. All patients were also evaluated with magnetic resonance imaging or computerized tomography myelography. Seven patients who presented initially with orthopedic deformity, skin stigmata, and neurological problems underwent primary cord untethering (Group 1). All seven patients were urologically asymptomatic; all but one had normal findings on urodynamic study. Eighteen patients with prior myelomeningocele closure underwent secondary untethering (Group 2). They presented with urological (11 cases), neurological (three cases), or both urological and neurological (four cases) deterioration. All patients underwent surgery via a microsurgical technique. At a mean follow-up time of 2 years, the only Group 1 patient with preoperative abnormal urodynamic findings normalized following untethering, whereas another asymptomatic patient showed worsened results on his postoperative study. In Group 2, all seven patients with preoperative neurological deterioration improved. Ten of the 15 patients who had isolated or associated preoperative clinical urological deterioration improved or stabilized, whereas five displayed continued deterioration in their bladder function. With respect to urodynamic studies, there was a significant increase in total and pressure-specific bladder capacities following untethering. We conclude that urodynamic studies are useful both diagnostically and in follow-up examinations of patients with tethered cord, that disturbances identified by these studies often precede clinical manifestations of deterioration, and that spinal cord untethering favorably influences the urological status in most patients.
Somatosensory evoked potential monitoring in cervical surgery: identification of pre- and intraoperative risk factors associated with neurological deterioration
Authors: May Daniel M. , Jones Stephen J. , Crockard H. Alan
Published: June 2009

✓ Cortical and subcortical somatosensory evoked potentials (SSEPs) were noninvasively monitored in 191 surgical procedures involving the cervical spine. In nine patients in the poorest neurological condition, SSEPs could not be monitored. Lower limb SSEPs were often too degraded to be useful.

Upper limb responses were reliably recorded in 182 procedures, with a sensitivity of 99% and a specificity of 27% in 10 patients who developed neurological signs postsurgery. The aim of monitoring was to detect changes in spinal cord function at a time when neurological deterioration could be prevented or reversed, and these studies alerted the authors to certain clinical and SSEP risk factors associated with deterioration. Clinical and operative risk factors were: 1) poor preoperative neurological function (one-third of Ranawat Class IIIb patients deteriorated); 2) use of instrumentation (the risk doubled in preoperatively unimpaired patients); 3) upper cervical and clival surgery (the risk tripled); and 4) and multi-segmental surgery (increased risk with each additional level).

There were SSEP changes in 33 patients. Fifty percent of patients with a complete loss had neurological damage, unlike those who had incomplete loss or whose electrical changes had recovered by the end of surgery. In the authors' view these “false positives” may represent real physiological changes, the effects of which might have been minimized by an alteration in the surgeon's response as a result of the warning. Although these initial studies have made this surgical team more alert to potential problems, the role of intraoperative SSEP monitoring is still being debated.
Predictors of outcome in the quadriparetic nonambulatory myelopathic patient with rheumatoid arthritis: a prospective study of 55 surgically treated Ranawat Class IIIb patients
Authors: Casey Adrian T. H. , Crockard H. Alan , Bland J. Martin , Stevens John , Moskovich Ronald , Ransford Andrew
Published: June 2009

✓ The functional results of surgery in patients with myelopathic nonambulatory rheumatoid arthritis (Ranawat Class IIIb) are often disappointing, with high rates of postoperative morbidity and mortality. The authors therefore undertook a detailed investigation of a cohort of 55 Ranawat Class IIIb patients (11 men and 44 women) with a mean age of 64.7 years who were recruited prospectively over a 10-year period (1983–1993), to determine what factors may accurately predict a good surgical outcome. Only 14 patients (25.5%) were judged to have had a favorable outcome as determined by an improvement to Ranawat Class I or II or an improvement of at least 0.5 points in the Stanford Health Assessment Questionnaire disability index. The early postoperative mortality rate was high (12.7%) in this group and almost one-quarter of the patients were dead within 6 months. These poor results mirror those already published in the existing literature.

Univariate analysis revealed that age (p = 0.02), degree of vertical translocation (p = 0.05), and, more importantly, spinal cord area (p = 0.006) were significant predictors of outcome. Multiple logistic regression analysis showed that spinal cord area (p = 0.026) was, in fact, the major determinant of outcome and, indeed, of long-term survival (p = 0.001). The mean spinal cord area of those patients not achieving a good outcome was 44 mm2. The atlantodens interval (ADI) was not shown to be a significant outcome determinant, which may be explained by the correlation between an increasing vertical translocation and a decreasing ADI (r = 0.4, p = 0.01). Furthermore, as the degree of vertical translocation increased, the space available for the cord was observed to decrease (p = 0.003) commensurate with a reduction in spinal cord area (p = 0.02). Together, these findings strongly argue for earlier surgical intervention, before the development of vertical translocation, permanent neurological damage, and spinal cord atrophy can occur.
Meningioma of the pineal region: a surgical series of 10 cases
Authors: Konovalov Alexander Nikolaevich , Spallone Aldo , Pitzkhelauri David Iraklevich
Published: June 2009

✓ Ten cases of meningioma of the pineal region were histologically verified at a single institution during an 8-year period. These represented 0.3% of 3061 intracranial meningiomas, as well as 6.2% of 164 pineal tumors. Patients were predominantly women. Symptoms and signs of increased intracranial pressure were most common, whereas Parinaud's syndrome was observed in only one case. Computerized tomography (CT) was the main diagnostic test used in the present series. It usually revealed a hyperdense mass with high-intensity contrast enhancement and a calcified mass eccentrically located at the periphery, which returned to its central location postsurgically and was likely to represent a calcified pineal gland. Magnetic resonance imaging was performed in the more recent cases and confirmed the suspicion raised by CT of a meningioma with a calcified mass at its periphery. Surgery was performed using an occipital transtentorial microsurgical approach with the patient placed in the semisitting position. Gross-total tumor removal was achieved in all cases, although this required sacrifice of the vein of Galen in six patients. Venous occlusion was performed only after adequate intraoperative verification of functional occlusion and blood flow diversion from the galenic system and had no consequences in any case but one. This latter patient had an infiltrative meningioma that was removed at the expense of intraoperative sacrifice of the two internal cerebral veins, as well as unavoidable trauma to the region of the quadrigeminal plate. All the remaining patients improved postsurgery, and only one had a permanent visual field deficit as a result of the surgical approach. Pineal meningiomas represent a rare subgroup of pineal tumors that can be treated surgically with reasonably good results. Sacrifice of major basal veins may be required to achieve radical tumor removal and can be tolerated by the patient provided that functional occlusion of the galenic system, as indicated by preoperative angiography, is verified during surgery.
Gamma knife radiosurgery in 11 hemangioblastomas
Authors: Niemelä Mika , Lim Young Jin , Söderman Michael , Jääskeläinen Juha , Lindquist Christer
Published: June 2009

✓ One suprasellar, one mesencephalic, and nine cerebellar hemangioblastomas were treated with the gamma knife in 10 patients (median age 48 years) in Stockholm between 1978 and 1993. Four patients had von Hippel—Lindau disease, a dominant inherited trait predisposing to multiple hemangioblastomas. Six hemangioblastomas were treated with radiotherapy at a median margin dose of 25 Gy (20–35 Gy) before 1990 and the next five with a median of 10 Gy (5–19 Gy). Computerized tomography or magnetic resonance images were available for 10 of the 11 hemangioblastomas at a median follow-up time of 26 months (4–68 months) after radiosurgery. The solid part of six hemangioblastomas shrank in a median of 30 months, whereas four hemangioblastomas were unchanged at a median of 14 months. Five hemangioblastomas had an adjoining cyst and three of these cysts had to be evacuated after radiosurgery. One solitary hemangioblastoma later developed a de novo cyst that also needed evacuation. One patient with two cerebellar hemangioblastomas (margin dose 25 Gy each) developed edema at 6 months and required a shunt and prolonged corticosteroid treatment. The combined follow-up data of the 23 hemangioblastomas in 15 patients from previous literature and the present series indicate that, first, a solitary small- or medium-sized hemangioblastoma usually shrinks or stops growing after radiosurgery. The recommended margin dose is 10 to 15 Gy. Second, the adjoining cyst often does not respond to radiosurgery but requires later, sometimes repeated evacuation.
Salvage chemotherapy for oligodendroglioma
Authors: Peterson Kendra , Paleologos Nina , Forsyth Peter , Macdonald David R. , Cairncross J. Gregory , _ _
Published: June 2009

✓ The authors present their experience with salvage chemotherapy for oligodendroglioma, an uncommon brain tumor that responds predictably to PCV (procarbazine, lomustine (CCNU), and vincristine) when given as initial therapy. The authors reviewed the records of patients with oligodendrogliomas who received a second, third, or fourth cytotoxic regimen prescribed to combat tumor recurrence documented by computerized tomography or magnetic resonance imaging following an initial chemotherapy program. Initial regimens were prescribed at various time points: as neoadjuvant therapy prior to radiotherapy, as adjuvant therapy in conjunction with radiotherapy, or at recurrence following radiotherapy. Response criteria were based on measurable changes in tumor size following published guidelines. Twenty-three patients (14 men and nine women) aged 25 to 58 years (median 36 years) received 33 salvage regimens. When non-PCV chemotherapy had been the prior regimen, seven (88%) of eight patients responded to salvage chemotherapy, all seven (100%) responding to PCV. Administration of PCV was effective after regimens of carmustine and CCNU but was ineffective after prior administration of PCV. When PCV had been given any time previously, only four (19%) of 21 patients responded to salvage chemotherapy; however, four (40%) of 10 patients who received etoposide (VP-16)/cisplatin (CDDP) responded. Despite the small number of patients, two noteworthy trends emerge from these data: first, PCV is a highly effective salvage treatment when used at tumor recurrence following non-PCV chemotherapy regimens, and second, the synergistic combination of VP-16 and CDDP may exert substantial antioligodendroglioma activity, and it warrants further evaluation.
Procarbazine, lomustine, and vincristine (PCV) chemotherapy for Grade III and Grade IV oligoastrocytomas
Authors: Kim Lyndon , Hochberg Fred H. , Thornton Allan F. , Harsh Griffith R. , Patel Heena , Finkelstein Dianne , Louis David N.
Published: June 2009

✓ The authors provided procarbazine, lomustine (CCNU), and vincristine (PCV) chemotherapy to 32 patients whose tumors contained varying mixtures of oligodendroglial and astrocytic cells. Twenty-five patients had oligodendroglioma—astrocytoma (oligoastrocytoma) with a histological Grade of III (19 patients) or IV (six patients); seven had anaplastic oligodendroglioma. The PCV therapy was administered every 6 weeks for a total of at least 124 cycles. The median duration of follow-up review from the start of chemotherapy was 19.3 months. Nineteen patients were treated before receiving radiation therapy and 12 after receiving it (one patient received concurrent radiotherapy and chemotherapy). Grade 3 or 4 hematological toxicity was experienced by nine (31%) of 29 patients. Ten patients had delayed treatment due to treatment-related toxicities (34.5%). Ninety-one percent of the 32 patients responded to the therapy. These included 10 patients with a complete response and 19 with a partial response. The median time to progression was 15.4 months for all patients and 23.2 months for those with Grade III tumors. The median time to progression for patients with Grade III oligoastrocytomas was 13.8 months; for those with Grade IV oligoastrocytoma it was 12.4 months and for those with anaplastic oligodendrogliomas it was 63.4 months (p = 0.0348). These patients survived a median of 49.8 months, 16 months, and 76 or more months, respectively, from the start of chemotherapy (p = 0.0154). The PCV therapy provides durable responses in patients with Grade III or IV oligoastrocytomas.
Cholesterol granulomas of the petrous apex: combined neurosurgical and otological management
Authors: Brodkey Jason A. , Robertson Jon H. , Shea John J. , Gardner Gale
Published: June 2009

✓ Cholesterol granulomas of the head are relatively rare. Isolated lesions of the cerebellopontine angle are even more uncommon. In this report, 17 cases of petrous apex cholesterol granulomas are presented and management is discussed.

Symptoms at presentation included dizziness (14 patients), pressure (nine patients), tinnitus (eight patients), hearing loss (eight patients), otalgia (six patients), headache (six patients), nausea (three patients), drainage from ear (two patients), facial pain (two patients), seizure (two patients), lightheadedness (one patient), hemifacial spasm (one patient), and facial numbness (one patient). Six cases were managed without surgery and 11 patients underwent operative procedures. The approaches used included the infralabyrinthine (eight patients), transcanal—infracochlear (two patients), and translabyrinthine (one patient). The mean follow-up period for all cases was 29.5 months. Of those patients managed without surgery, symptoms improved in all except one, whose tinnitus was slightly worse. Of surgically treated patients, symptoms improved or remained the same except in one with worsened dizziness. There were nine patients with hearing present presurgery and seven whose hearing was preserved postsurgery. The authors present a case that was managed at another center where an attempt at surgical resection through a subtemporal middle fossa approach was unsuccessful. This lesion was successfully treated using an infralabyrinthine approach with drainage into the mastoid cavity.

Cholesterol granulomas of the petrous apex can be managed without surgery when symptoms are stable or improve. Otherwise, a transmastoid extradural approach with simple drainage into the mastoid sinus or middle ear produces symptomatic improvement with low morbidity. Resection of petrous apex cholesterol granulomas is not necessary.