bluuebunny/crossref_metadata_2025 huggingface dataset:
Computerized tomography angiography of ruptured cerebral aneurysms: factors affecting time to maximum contrast concentration
Authors: Nakajima Yoshikazu , Yoshimine Toshiki , Yoshida Hiroyoshi , Sakashita Keiji , Okamoto Mitsutoyo , Kishikawa Masanobu , Yagi Keiichi , Yokota Junichiro , Hayakawa Toru
Published: June 2009

Object. This study was conducted to assess the diagnostic value of three-dimensional computerized tomography (3-D CT) angiography in demonstrating cerebral aneurysms in 42 consecutive patients presenting with acute subarachnoid hemorrhage (SAH).

Methods. To obtain the volume data for selective visualization of the cerebral arteries without enhancement of the venous system, the time delay was established between the injection of contrast medium and the start of scanning by using two different methods. The circulation time was calculated with Schad's formula in the first 13 cases, but the results were not satisfactory. In the 29 subsequent cases the time delay was established using a single-level dynamic CT prescan. The dynamic prescan demonstrated the statistical differences in peak time with regard to patient age, SAH grade, and the postresuscitation state after cardiopulmonary arrest. The 3-D CT angiograms were generated from the volume data by using a voxel transmission method. Computerized tomography angiography obtained after optimally adjusted time delay demonstrated the contour of the cerebral arteries in 97% of cases, and aneurysms were detected in 93%. Enhancement of the cavernous sinus and major cortical veins was avoided. Even in patients who suffered cardiopulmonary arrest, images of the major arteries were clearly demonstrated after resuscitation.

Conclusions. In an emergency situation, CT angiography with a dynamic prescan may be an alternative to magnetic resonance angiography or digital subtraction angiography in the diagnosis of ruptured aneurysms. This modality would also be useful for the precise assessment of small aneurysms, blebs, and aneurysms adjacent to the cavernous sinus.
Computerized tomography angiography in isolated third nerve palsies
Authors: McFadzean Robert M. , Teasdale Evelyn M.
Published: June 2009

Object. The goal of this study was to assess the value of computerized tomography (CT) angiography as a diagnostic tool in isolated oculomotor nerve palsies.

Methods. One hundred consecutive patients who presented with an isolated third nerve palsy were examined by CT angiography. This procedure was followed by conventional cerebral angiography in most patients in whom a vascular abnormality was noted on the CT angiography. Thus, all patients whose symptoms were caused by a compressive aneurysm were identified. The remaining patients were observed clinically to exclude the possibility that a missed cerebral aneurysm caused the isolated third nerve palsy.

Eighteen patients harbored a cerebral aneurysm responsible for causing the isolated third nerve palsy. Most of the remaining patients experienced some degree of spontaneous recovery. There was no clinical evidence to indicate that a case of compressive cerebral aneurysm causing the isolated third nerve palsy had been missed on CT angiography.

Conclusions. Computerized tomography angiography is a reliable diagnostic tool for use in the assessment of patients with an isolated third nerve palsy; it can identify the minority of patients in whom conventional cerebral angiography may be required.
Intrauterine high-resolution magnetic resonance imaging in fetal hydrocephalus and prenatal estimation of postnatal outcomes with “perspective classification”
Authors: Oi Shizuo , Honda Yumie , Hidaka Mitsuru , Sato Osamu , Matsumoto Satoshi
Published: June 2009

Object.It is possible to diagnose hydrocephalus prenatally based on the morphological appearance of the fetus on neurodiagnostic images; however, the prognosis of this disease shows wide variation. The authors previously proposed a classification system for the prediction of postnatal outcome based on progression of hydrocephalus and affected brain development, known as the “Perspective Classification of Congenital Hydrocephalus (PCCH).” In this study the authors have used their classification system to analyze long-term follow-up results obtained in each clinicoembryological stage of fetal hydrocephalus.

Methods.Sixty-one fetuses with hydrocephalus were examined to predict postnatal outcome by using this newly developed classification. The authors' recently developed method of using heavily T2-weighted imaging with a superconducting magnet clearly delineated the cerebrospinal fluid (CSF) space and the malformed brain and spinal cord. Imaging was achieved in less than 1 second per slice and required no sedation of the fetus. The technique appears to be simple and good at delineating intrauterine anatomy.

Hydrocephalus was diagnosed in two fetuses at PCCH embryological Stage I (8–21 gestational weeks), in 28 fetuses at Stage II (22–31 weeks), and in 31 fetuses at Stage III (32–40 weeks). Among these 61 fetuses, clinicopathological typing showed that 19 had primary hydrocephalus (nine in Stage II and 10 in Stage III), 34 had dysgenetic hydrocephalus (two in Stage I, 16 in Stage II, and 16 in Stage III), and eight had secondary hydrocephalus (three in Stage II and five in Stage III). When the hydrocephalic state developed during PCCH Stage I or II, the prognosis was very poor, and only one of 18 fetuses with dysgenetic hydrocephalus and none of three fetuses with secondary hydrocephalus had an acceptable postnatal outcome. Even within the same category or subtype of fetal hydrocephalus, such as primary hydrocephalus in its simple form, or hydrocephalus with spina bifida aperta (myeloschisis), the postnatal outcomes differed depending on the time of onset of hydrocephalus. When the diagnosis of hydrocephalus was made during PCCH Stage II, the fetuses had a poorer postnatal outcome compared with those at Stage III (p < 0.05).

Conclusions.It is emphasized that postnatal prognosis is not simply a function of the form of the diagnosis but is also dependent on the progression of hydrocephalus and the degree to which that process affects neuronal development. Early decompressive procedures, conventionally performed after but, hopefully, performed before birth, are indicated to obtain the optimal postnatal prognosis of fetuses with hydrocephalus diagnosed at PCCH Stage II.
Increased hematocrit and decreased transfusion requirements in children given erythropoietin before undergoing craniofacial surgery
Authors: Helfaer Mark A. , Carson Benjamin S. , James Carol S. , Gates Judy , Della-Lana David , Kolk Craig Vander
Published: June 2009

Object.This study was undertaken to determine the efficacy of preoperative erythropoietin administration in infants scheduled for craniofacial surgery and, in so doing, to minimize problems associated with blood transfusions.

Methods.Families were offered the option of having their children receive erythropoietin injections before undergoing craniofacial surgery. The children whose families accepted this option received daily iron and 300 U/kg erythropoietin three times per week for 3 weeks preoperatively. Weekly complete blood counts with reticulocyte counts were measured and transfusion requirements were noted. Blood transfusions were administered depending on the clinical condition of the child. A case-matched control population was also evaluated to compare initial hematocrit levels and transfusion requirements. Thirty patients in the erythropoietin treatment group and 30 control patients were evaluated. The dose of erythropoietin administered was shown to increase hematocrit levels from 35.4 ± 0.9% to 43.3 ± 0.9% during the course of therapy. The resulting hematocrit levels in patients treated with erythropoietin at the time of surgery were higher compared with baseline hematocrit levels obtained in control patients at the time of surgery (34.2 ± 0.5%). Transfusion requirements also differed: all control patients received transfusions, whereas 64% (19 of 30) of erythropoietin-treated patients received transfusions.

Conclusions.The authors conclude that treatment with erythropoietin in otherwise healthy young children will increase hematocrit levels and modify transfusion requirements. Erythropoietin therapy for elective surgery in children of this age must be individualized according to the clinical situation, family and physician beliefs, and cost effectiveness, as evaluated at the individual center.
Preservation of ejaculatory function by reconstruction of the canine hypogastric nerve
Authors: Kihara Kazunori , Sato Kenji , Ishizaka Kazuhiro , Oshima Hiroyuki
Published: June 2009

Object. The hypogastric nerve (HGN) plays a crucial role in the primary functions of ejaculation: sperm transport through the vas deferens, secretion of prostatic fluid, and bladder neck closure. This study was undertaken to explore the possibility of restoring HGN function to the seminal tract and preserving its cross-innervation mechanism to the seminal tract after HGN—HGN reattachment.

Methods. Responses of the vas deferens/epididymis, prostate, and bladder neck to electrical stimulation of the lumbar splanchnic nerve (LSN) or the HGN and occurrence of antegrade ejaculation as a result of manual penile stimulation were examined in dogs that had undergone HGN—HGN reattachment. Eighteen months after the procedure had been performed bilaterally, 23 LSNs were electrically stimulated. In 17 LSNs this stimulation elicited elevation of vasal pressure (12 nerves bilaterally); in 18 LNs, bladder neck pressure; and in 15 LSNs, prostate contraction. After retransection of the right HGN in the dogs that had undergone HGN—HGN reattachment, 11 right-sided LSNs were stimulated; in seven LSNs, the stimulation elicited elevation of vasal pressure (five bilaterally), in seven bladder neck pressure, and in six prostate contraction. Twelve left-sided LSNs were stimulated; in seven LSNs, the stimulation elicited elevation of vasal pressure (four bilaterally), in six bladder neck pressure, and in six prostate contracton. Each of the 12 HGN stimulations made proximal to the site that had been sutured in dogs that had HGN-HGN reattachment caused responses of the three organs specified above that were comparable to those in control dogs. Manual penile stimulation elicited antegrade ejaculation in all three dogs examined.

Conclusions. The results of this study show that the function of the HGN in the seminal tract can be preserved after HGN—HGN reattachment and that restoration of its cross-innervation mechanism is possible.
Superimposed holographic image—guided neurosurgery
Authors: Ko Kathryn
Published: June 2009

✓ Computerized tomography scanning—derived narrow band reflection holograms of patients undergoing craniofacial procedures were created to evaluate the applicability of superimposing these three-dimensional images (3-D) on the operative field during neurological surgery. These sterilized radiological holograms were positioned over the surgical site by using bone sutures as registration points between the skull and the 3-D image to serve as a visual template between the patient and surgeon. Surgeries were then performed with the surgeon looking through the radiological hologram at the patient. Holograms were accurate to within 2 mm (plus or minus) of the actual calvarial anatomy. The use of the holographic image as a visual guide during surgery eliminated intraoperative guesswork or free-handed contouring. To the author's knowledge, this is the first report of the superimposed holographic image used in situ during surgery.
Cerebral perfusion pressure in head-injured patients: a noninvasive assessment using transcranial Doppler ultrasonography
Authors: Czosnyka Marek , Matta Basil F. , Smielewski Piotr , Kirkpatrick Peter J. , Pickard John D.
Published: June 2009

Object. The authors studied the reliability of a new method for noninvasive assessment of cerebral perfusion pressure (CPP) in head-injured patients in which mean arterial blood pressure (ABP) and transcranial Doppler middle cerebral artery mean and diastolic flow velocities are measured.

Methods. Cerebral perfusion pressure was estimated (eCPP) over periods of continuous monitoring (20 minutes—2 hours, 421 daily examinations) in 96 head-injured patients (Glasgow Coma Scale score < 13) who were admitted to the intensive care unit. All patients were sedated, paralyzed, and ventilated. The eCPP and the measured CPP (ABP minus intracranial pressure, measured using an intraparenchymal microsensor) were compared.

The correlation between eCPP and measured CPP was r = 0.73; p < 10−6. In 71% of the examinations, the estimation error was less than 10 mm Hg and in 84% of the examinations, the error was less than 15 mm Hg. The method had a high positive predictive power (94%) for detecting low CPP (< 60 mm Hg). The eCPP also accurately reflected changes in measured CPP over time (r > 0.8; p < 0.001) in situations such as plateau and B waves of intracranial pressure, arterial hypotension, and refractory intracranial hypertension. A good correlation was found between the average measured CPP and eCPP when day-by-day variability was assessed in a group of 41 patients (r = 0.71).

Conclusions. Noninvasive estimation of CPP by using transcranial Doppler ultrasonography may be of value in situations in which monitoring relative changes in CPP is required without invasive measurement of intracranial pressure.
Endoscopic treatment of carpal tunnel syndrome: a critical review
Authors: Jimenez David F. , Gibbs Scott R. , Clapper Adam T.
Published: June 2009

Object. The goal of this paper is to present a critical review of the endoscopic procedures currently in use for the treatment of carpal tunnel syndrome. Endoscopic techniques and outcomes are discussed.

Methods. An extensive review of published articles on the subject of endoscopic carpal tunnel release surgery is presented, encompassing six endoscopic techniques used to treat carpal tunnel syndrome. Since the first report in 1987, 7091 patients have undergone 8068 operations. The overall success rate has been 96.52%, with a complication rate of 2.67% and a failure rate of 2.61%. The mean time to return to work in patients not receiving Workers' Compensation was 17.8 days, ranging between 10.8 and 22.3 days. The most common complications were transient paresthesias of the ulnar and median nerves. Other complications included superficial palmar arch injuries, reflex sympathetic dystrophy, flexor tendon lacerations, and incomplete transverse carpal ligament division. In many studies in which open and endoscopic techniques were compared, it was reported that patients in the the latter group experienced significantly less pain and returned to work and activities of daily living earlier.

Conclusions. Success and complication rates of endoscopic carpal tunnel release surgery are similar to those for standard open procedures.
Factors associated with survival in patients with meningioma
Authors: McCarthy Bridget J. , Davis Faith G. , Freels Sally , Surawicz Tanya S. , Damek Denise M. , Grutsch James , Menck Herman R. , Laws Edward R.
Published: June 2009

Object. To explore factors affecting the survival rate in patients with meningiomas, the authors used the National Cancer Data Base (NCDB), which includes tumors from approximately 1000 hospitals participating in the American College of Surgeons tumor registry program.

Methods. Analysis included over 9000 cases diagnosed from 1985 to 1988 and 1990 to 1992. Survival estimates were computed and prognostic factors were identified using a proportional hazards model. The overall 5-year survival rate was 69% and it declined with patient age. This rate was 81% in patients aged 21 to 64 years and 56% for patients 65 years of age or older. When patients were grouped by the histological type of their tumors, those with benign tumors had an overall 5-year survival rate of 70%, whereas the overall 5-year survival rates in patients with atypical and malignant meningiomas were 75% and 55%, respectively. Prognostic factors for benign tumors included age at diagnosis, tumor size, whether treated surgically, hospital type, and radiation therapy; for malignant tumors, the prognostic factors included: age at diagnosis, whether treated surgically, and radiation therapy. These factors were statistically significant. The 5-year rate for recurrence of symptoms (regardless of the method of treatment) was 19.2% for those with benign tumors and 32.4% for those with malignant tumors. In patients whose benign tumor had been completely removed, the 5-year rate of tumor recurrence was 20.5%.

Conclusions. Although not population-based, the NCDB has the potential for providing pertinent information regarding patient characteristics and methods of treatment for benign, as well as malignant, brain tumors.
Does the size of intracranial aneurysms change with intracranial pressure? Observations based on color “power” transcranial Doppler ultrasound
Authors: Wardlaw Joanna M. , Cannon James , Statham Patrick F. X. , Price Rupert
Published: June 2009

Object. The authors sought to determine whether the increased pulsatility of aneurysms, compared with normal intracranial arteries, on color “power” transcranial Doppler (TCD) ultrasound was due to a true change in aneurysm size and whether aneurysm dimensions change with intracranial pressure (ICP).

Methods. The authors studied nine patients who had suffered recent subarachnoid hemorrhages complicated by hydrocephalus requiring intraventricular cerebrospinal fluid drainage, in whom the presence of an aneurysm was confirmed on angiographic examination. Color “power” TCD studies of the intracranial arteries and aneurysm were obtained through the temporal bone window before and after insertion of the ventricular drain and then at different known ICPs.

Of the nine patients studied, four were examined both before and after insertion of a ventricular drain. At high ICPs, aneurysms appeared very “pulsatile” and the maximum cross-sectional area was small, whereas at low ICPs, aneurysms appeared larger and were much less pulsatile. The normal arteries did not change significantly in terms of pulsatility or maximum cross-sectional area at different levels of ICP.

Conclusions. The change in aneurysm size visualized with the aid of color power TCD is likely to be real. Aneurysm dimensions vary with ICP levels; the lesions are larger and less pulsatile at low ICPs and smaller but more pulsatile at high ICPs.
Terson's syndrome in subarachnoid hemorrhage and severe brain injury accompanied by acutely raised intracranial pressure
Authors: Medele Ralph J. , Stummer Walter , Mueller Arthur J. , Steiger Hans-Jakob , Reulen Hans-Jürgen
Published: June 2009

Object. The syndrome of retinal or vitreous hemorrhage in association with subarachnoid hemorrhage (SAH) is known as Terson's syndrome. The authors' purpose was to determine whether intraocular hemorrhage occurs with similar incidence when caused by severe brain injury accompanied by acutely raised intracranial pressure (ICP).

Methods. Prospective ophthalmological examination was performed in 22 consecutive patients with SAH or severe brain injury and elevated ICP. Thirteen patients were admitted for SAH (World Federation of Neurological Surgeons Grades II–IV) and nine for severe brain injury (Glasgow Coma Scale scores 3–10). Monitoring of ICP was performed at the time of admission via a ventricular catheter. Initial ICP exceeded 20 mm Hg in all patients. Indirect ophthalmoscopy without induced mydriasis was performed within the 1st week after the acute event. Retinal or vitreous hemorrhage was seen in six (46%) of 13 patients with SAH and in four (44%) of nine patients with severe brain injury. Ocular bleeding was found bilaterally in three patients with SAH and in one patient with severe brain injury (18%). Six of the 10 patients with Terson's syndrome died as a result of their acute event.

Conclusions. The present results indicate that Terson's syndrome may be related to acute elevation of ICP, independent of its causes, and may occur with similar incidence in patients with severe brain injury and those with SAH. Because recognition and treatment of Terson's syndrome may prevent visual impairment and associated secondary damage to the eye, increased awareness of this entity in all patients with acute raised intracranial hypertension is recommended.
The presence of 4-hydroxynonenal/protein complex as an indicator of oxidative stress after experimental spinal cord contusion in a rat model
Authors: Baldwin Stanley A. , Broderick Richard , Osbourne David , Waeg Georg , Blades Deborah A. , Scheff Stephen W.
Published: June 2009

Object. The authors tested the hypothesis that breach of the blood—spinal cord barrier (BSCB) will produce evidence of oxidative stress and that a similar staining pattern will be seen between 4-hydroxynonenal (HNE)/protein complexes and extravasated immunoglobulin G (IgG).

Methods. Adult female Fischer 344 rats, each weighing 200 to 225 g, were subjected to a spinal cord contusion at T-10 by means of a weight-drop device. Spinal cord tissue was assessed for oxidative stress by localizing extravasated plasma contents with a monoclonal antibody for rat IgG and protein conjugation with HNE, which is an aldehyde byproduct of lipid peroxidation. The animals were killed at 1 and 6 hours, and 1, 2, and 7 days after surgery. Maximum HNE/protein staining was observed at 2 days postinjury, and HNE/protein and IgG manifested similar staining patterns. Analysis revealed a graduated but asymmetrical rostral—caudal response relative to the T-10 injury site. Both HNE/protein complex and IgG staining revealed that the caudal levels T-11 and T-12 stained significantly more intensely than the rostral levels T-9 and T-8, respectively. A higher percentage of neurons positive for HNE/protein immunostaining was observed in spinal cord levels caudal to the injury site compared with equidistant rostral regions. Protein dot-blot assays also revealed a similar asymmetrical rostral—caudal HNE/protein content.

To analyze the timing of the BSCB breach, another group of animals received identical contusions, and horseradish peroxidase (HRP) was injected 10 minutes before or at various times after injury (1, 3, and 6 hours, and 1, 2, and 7 days). Maximum HRP permeability was seen immediately after injury, with a significant decrease occurring by 1 hour and a return to control levels by 2 days posttrauma.

Conclusions. Data from this study indicate possible compromise of neuronal, axonal, glial, and synaptic function after trauma, which may be a factor in motor deficits seen in animals after spinal cord contusion. The colocalization of the IgG stain with the HNE/protein stain is consistent with the hypothesis of a mutual cause—effect relationship between BSCB and oxidative stress in central nervous system trauma.
Spinal epidural cavernous hemangiomas
Authors: Zevgaridis Dimitris , Büttner Andreas , Weis Serge , Hamburger Christoph , Reulen Hans-Jürgen
Published: June 2009

✓ Epidural cavernous hemangiomas are increasingly identified as a cause of acute or chronic progressive spinal cord syndrome and local back pain or radiculopathy. The authors present three cases of spinal epidural cavernous hemangiomas manifesting as spinal cord syndrome, thoracic radiculopathy, and lumbar radiculopathy. Based on the imaging characteristics of these three cases and a review of the literature, the clinical signs and symptoms and their implications, the role of preoperative neuroradiological diagnosis, and the need for complete surgical resection are discussed. Epidural cavernous hemangiomas display consistent magnetic resonance imaging properties: T1-weighted images most commonly show a homogeneous signal intensity similar to those of spinal cord and muscle, and contrast enhancement is homogeneous or slightly heterogeneous. On T2-weighted images the signal of the lesion is consistently high and slightly less intense than that of cerebrospinal fluid. Frequently, the lesion is characterized by its extension through the intervertebral foramen. Awareness of these characteristics facilitates diagnosis and treatment of the lesions. Despite the risk of bleeding, in all three cases complete surgical excision was achieved.
Spinal dural enhancement on magnetic resonance imaging associated with spontaneous intracranial hypotension
Authors: Moayeri N. Nicole , Henson John W. , Schaefer Pamela W. , Zervas Nicholas T.
Published: June 2009

✓ This report offers a description of typical changes seen on gadolinium-enhanced magnetic resonance (MR) imaging of the entire spine that indicate spontaneous intracranial hypotension (SIH). To the authors' knowledge, this is the first report of its kind. They describe three cases of SIH that were accompanied by dural enhancement throughout the neuraxis on imaging, with the evolution of associated subdural and epidural fluid collections in the spine. Recognition of this disorder is important to be able to distinguish it from an infectious or neoplastic process in which surgical intervention might be warranted. Evaluation using gadolinium-enhanced cranial and spinal MR imaging in patients with postural headaches and an 111In-labeled cerebrospinal fluid leak study are discussed. Treatment with an epidural blood patch is shown to be particularly effective, with resolution of the radiological and clinical findings.
Surgical experience with an implanted artificial cervical joint
Authors: Cummins Brian H. , Robertson James T. , Gill Steven S.
Published: June 2009

Object. To assess the effectiveness of Cummins' artificial cervical joint, the authors reviewed the cases of 20 patients in whom the joint had been placed.

Methods. A review of patients' medical records and reexamination of 18 patients were performed. The review of the surgical experience with the implantation of movable stainless-steel joints in 20 patients treated for cervical myelopathy (16 patients), cervical radiculopathy (three patients), and severe pain (one patient) indicated that the procedure is safe and well tolerated and does preserve cervical joint motion in most patients over an extended period of observation. To date, adjacent segmental symptomatic degenerative changes leading to further surgical treatment have been avoided. The joint has been placed in patients with advanced congenital and acquired cervical fusion and has been demonstrated to be stable, mobile, and biomechanically and biochemically compatible; it has shown no subsidence into adjacent bone. Wear debris has not occurred.

Conclusions. The use of stainless steel in the cervical spine appears to be suitable for this joint replacement design.
Long-term evaluation of reconstruction of the sellar floor with a silicone plate in transsphenoidal surgery
Authors: Kabuto Masanori , Kubota Toshihiko , Kobayashi Hidenori , Takeuchi Hiroaki , Nakagawa Takao , Kitai Ryuhei , Kodera Toshiaki , Kawai Hideya , Arishima Hidetaka
Published: June 2009

Object. The authors have used a silicone plate for reconstruction of the sellar floor during rhinoseptoplastic transsphenoidal surgery because it has greater elasticity and is easier to carve than nasal septal cartilage and sphenoid sinus bone. This study was designed to evaluate the usefulness of this technique based on the authors' experience during the past 7.6 years.

Methods. A silicone plate was used to reconstruct the sellar floor in 69 consecutive patients with sellar tumors that included 60 pituitary adenomas and nine Rathke's cleft cysts. The patients ranged in age from 16 to 82 years (mean 52 years). The postoperative position of the silicone plate could be clearly identified on sagittal or coronal magnetic resonance (MR) imaging as a very low intensity plate (void signal). No displacement or migration of the implanted silicone plate was observed on follow-up MR imaging in any patient. Infections of the lesion such as a pituitary abscess were not observed clinically or radiologically in any patient. Of the 16 patients with intraoperative cerebrospinal fluid (CSF) leakage, only one patient who had a ghost sella developed postoperative CSF rhinorrhea. In all seven patients who underwent repeated surgery for residual or recurrent tumor, the silicone plate that had been placed at the initial procedure was covered with a relatively thin fibrous capsule and the plate was well preserved. The silicone plate was easily removed at reoperation and was useful for detection of the sellar floor window made previously.

Conclusions. These results indicate that a silicone plate can be useful for reconstruction of the sellar floor in rhinoseptoplastic transsphenoidal surgery.
Congenital tethered spinal cord syndrome in adults
Authors: Iskandar Bermans J. , Fulmer Benjamin B. , Hadley Mark N. , Oakes W. Jerry
Published: June 2009

Object.The management of tethered spinal cord syndrome with onset of symptomatology occurring in adulthood remains controversial, although the necessity of early surgery in the pediatric tethered cord syndrome population is well established. To ascertain the results of surgery in adult patients with this anomaly, the authors undertook a retrospective review of 34 cases.

Methods.The authors studied the hospital records of 34 consecutive patients who presented in adulthood with tethered cord syndrome and conducted follow-up phone interviews with 28 of them. The population consisted of 12 men and 22 women, ranging in age from 18 to 70 years (mean 34 years). The most common presenting feature was pain, followed by weakness and incontinence. All patients underwent surgery. The most common operative findings were tight filum terminale, split cord malformation, and lipomyelomeningocele, paralleling those observed in pediatric studies.

Long-term surgical results and patient outcome ratings were encouraging. After a mean clinical follow-up period of 4 years, significant improvement occurred in 22 of 27 patients presenting with pain, 13 of 27 patients with motor or sensory dysfunction, and 11 of 18 patients with bowel and bladder disturbance. In addition, telephone interviews were obtained after a period of 8.6 years. Twenty-two (79%) of 28 patients called the operation a long-term success; 21 (75%) of 28 patients believed that they had significant postoperative improvement (and not just stabilization) in pain and/or neurological function. Surgical complications were generally minor.

Nineteen (86%) of 22 employed patients returned to work after surgery. Two (33%) of six patients who were not employed before surgery worked full time postoperatively. Only two of the 28 patients interviewed had received Workers' Compensation benefits; both of these had good outcomes and returned to work.

Conclusions.Tethered spinal cord syndrome in adults is an uncommon entity that can become symptomatic. Although surgery in adults involves greater risk of neurological injury than in children, it is a low-risk procedure with encouraging results. Because neurological deficits are generally irreversible, early surgery is recommended.
Basilar invagination: a study based on 190 surgically treated patients
Authors: Goel Atul , Bhatjiwale Mohinish , Desai Ketan
Published: June 2009

Object. The authors analyzed the cases of 190 patients with basilar invagination that was diagnosed on the basis of criteria laid down in 1939 by Chamberlain to assess the appropriate surgical procedure.

Methods. Depending on the association with Chiari malformation, the anomaly of basilar invagination was classified into two groups. Eighty-eight patients who had basilar invagination but no associated Chiari malformation were assigned to Group I; the remainder of the patients, who had both basilar invagination and Chiari malformation, were assigned to Group II. The principal pathological characteristic was observed to be direct brainstem compression due to odontoid process indentation in Group I and a reduction in posterior cranial fossa volume in Group II.

Conclusions. Despite the anterior concavity of the brainstem in both groups, transoral surgery was the most suitable procedure for those patients in Group I and decompression of the foramen magnum was found to be appropriate for patients in Group II. After surgical decompression, a fixation procedure was found to be necessary in most Group I cases, but only in a small minority of Group II cases.
Mechanical dysfunction of ventriculoperitoneal shunts caused by calcification of the silicone rubber catheter
Authors: Boch Anne-Laure , Hermelin Éric , Sainte-Rose Christian , Sgouros Spiros
Published: June 2009

Object. The authors studied new and calcified shunt catheters to identify the prevalence of failures caused by aging materials in the shunt. Complications associated with these devices have various origins. Among late complications, fracture or migration of the system is related to the subcutaneous adhesion of the distal tubing in a growing child. A review of a cohort of 64 children who underwent shunt placement in 1980 with barium-impregnated distal catheters showed that 10 of these patients underwent reoperation for complications related to aging of the shunt material. This group represents 15% of the whole series and 30% of those children who were followed for more than 3 years. The true impact of aging of materials on shunt function is probably underestimated.

Methods. The authors performed physical, chemical, and mechanical analyses of the retrieved aged catheters and also of new catheters, resulting in the following findings: 1) calcifications were observed only on the external surface of the catheter, predominantly in its subcutaneous segment at the level of the neck and anterior chest wall; 2) calcifications contained particles of free silicon and barium sulfate, signifying fragmentation of the polymer; 3) the microstructure of the silicone polymer was modified: microfractures and alteration of the polymeric network were observed; 4) silanol groups were observed on the external surface of the catheter; and 5) the mechanical properties of the silicone rubber were degraded, and the aged catheters were more brittle than the new ones, with ruptures at elongations and fracture energy much lower than that seen in new catheters.

Furthermore, in vitro testing with a metastable solution of simulated body fluid demonstrated the critical impact of pH variations in liquid media and surface degradation of the catheters on the precipitation of hydroxylapatite crystals.

Conclusions. Although most shunt complications can be addressed by better patient management and surgical technique, late complications appear to be partly related to aging of the material. Distal tubing calcifications have been observed in barium-impregnated catheters. The industry recently responded to these observations by introducing plain silicone-coated shunt tubing; further evaluation will show what improvement can be expected.
Tympanic membrane displacement testing in regular assessment of intracranial pressure in eight children with shunted hydrocephalus
Authors: Samuel Madan , Burge David M. , Marchbanks Robert J.
Published: June 2009

Object. The authors assessed the accuracy and repeatability of the tympanic membrane displacement (TMD) test, an audiometric technique that is used to evaluate changes in intracranial pressure (ICP) in children with shunted hydrocephalus.

Methods. A prospective comparative evaluation of 31 clinical episodes of shunt malfunction was made by using the serial TMD test and direct ICP measurement in eight children with shunted hydrocephalus between January 1995 and February 1996.

The volume displacement of the tympanic membrane (Vm) on stapedial contraction was inward for raised ICP in 11 instances and ranged from −120 to −539 nl (mean −263.5 nl). This was confirmed by direct ICP monitoring, which showed values ranging from 20 to 30 mm Hg (mean 26 mm Hg). The TMD test measurement (Vm) in 18 instances of low ICP ranged from 263 to 717 nl (mean 431.3 nl); this was corroborated by direct ICP measurement, which ranged from 3 to 7 mm Hg (mean 4.2 mm Hg). The normal baseline Vm values obtained when patients were asymptomatic ranged from −98 to 197 nl (mean 110 nl). As a noninvasive diagnostic tool used in predicting changes in ICP, the TMD test had a sensitivity of 83% and specificity of 100%. The positive predictive value of the test was 100% and the negative predictive value was 29%.

Conclusions. The TMD test can be used on a regular basis as a reproducible investigative tool in the assessment of ICP in children with shunted hydrocephalus, thereby reducing the need for invasive ICP monitoring. The equipment necessary to perform this testing is mobile. It will provide a useful serial guide to ICP abnormalities in children with shunted hydrocephalus.
Stereotactic radiosurgery for recurrent surgically treated acromegaly: comparison with fractionated radiotherapy
Authors: Landolt Alex M. , Haller Dieter , Lomax Nicoletta , Scheib Stefan , Schubiger Othmar , Siegfried Jean , Wellis Georgios
Published: June 2009

Object. The authors tested the assumption that gamma knife radiosurgery is more effective than fractionated radiotherapy for the treatment of patients with acromegaly who have undergone unsuccessful resective surgery. Untreated and uncured acromegaly causes illness and death. Acromegalic patients in whom growth hormone and, particularly, insulin-like growth factor I are not normalized must undergo further treatment.

Methods. After unsuccessful operations, 16 patients suffering from recurrent and uncured acromegaly underwent stereotactic radiosurgery (25 Gy to the tumor margin, 50 Gy maximum), the outcome of which was compared with the result obtained in 50 patients who received fractionated radiotherapy (40 Gy). The cumulative distribution functions of the two groups (Kaplan—Meier estimate) differed significantly (p < 0.0001 in the log-rank test of Mantel). The mean time to simultaneous normalization of both parameters was 1.4 years in the group treated with the gamma knife and 7.1 years in the group treated with fractionated radiotherapy.

Conclusions. The authors suggest the use of stereotactic radiosurgery as the preferred treatment for recurrent acromegaly resulting from unsuccessfully resected tumors.
Early metabolic alterations in edematous perihematomal brain regions following experimental intracerebral hemorrhage
Authors: Wagner Kenneth R. , Xi Guohua , Hua Ya , Kleinholz Marla , de Courten-Myers Gabrielle M. , Myers Ronald E.
Published: June 2009

Object.The authors previously demonstrated, in a large-animal intracerebral hemorrhage (ICH) model, that markedly edematous (“translucent”) white matter regions (> 10% increases in water contents) containing high levels of clotderived plasma proteins rapidly develop adjacent to hematomas. The goal of the present study was to determine the concentrations of high-energy phosphate, carbohydrate substrate, and lactate in these and other perihematomal white and gray matter regions during the early hours following experimental ICH.

Methods.The authors infused autologous blood (1.7 ml) into frontal lobe white matter in a physiologically controlled model in pigs (weighing approximately 7 kg each) and froze their brains in situ at 1, 3, 5, or 8 hours postinfusion. Adenosine triphosphate (ATP), phosphocreatine (PCr), glycogen, glucose, lactate, and water contents were then measured in white and gray matter located ipsi- and contralateral to the hematomas, and metabolite concentrations in edematous brain regions were corrected for dilution.

In markedly edematous white matter, glycogen and glucose concentrations increased two- to fivefold compared with control during 8 hours postinfusion. Similarly, PCr levels increased several-fold by 5 hours, whereas, except for a moderate decrease at 1 hour, ATP remained unchanged. Lactate was markedly increased (approximately 20 µmol/g) at all times. In gyral gray matter overlying the hematoma, water contents and glycogen levels were significantly increased at 5 and 8 hours, whereas lactate levels were increased two- to fourfold at all times.

Conclusions.These results, which demonstrate normal to increased high-energy phosphate and carbohydrate substrate concentrations in edematous perihematomal regions during the early hours following ICH, are qualitatively similar to findings in other brain injury models in which a reduction in metabolic rate develops. Because an energy deficit is not present, lactate accumulation in edematous white matter is not caused by stimulated anaerobic glycolysis. Instead, because glutamate concentrations in the blood entering the brain's extracellular space during ICH are several-fold higher than normal levels, the authors speculate, on the basis of work reported by Pellerin and Magistretti, that glutamate uptake by astrocytes leads to enhanced aerobic glycolysis and lactate is generated at a rate that exceeds utilization.
Enhanced endogenous antioxidant activity and inhibition of cerebral vasospasm in rabbits by pretreatment with a nontoxic endotoxin analog, monophosphoryl lipid A
Authors: Toyoda Tomikatsu , Kwan Aij-Lie , Bavbek Murad , Kassell Neal F. , Wanebo John E. , Lee Kevin S.
Published: June 2009

Object.Monophosphoryl lipid A (MPL) and diphosphoryl lipid (DPL) are derivatives of the lipopolysaccharide (endotoxin) ofSalmonella minnesotastrain R595. Monophosphoryl lipid A is relatively nontoxic and can stimulate the natural defense or immune system. Diphosphoryl lipid is relatively toxic; however, at higher concentrations, it can also stimulate an immune response. The purpose of the present study was to determine the effects of these endotoxin analogs on cerebral vasospasm after the onset of subarachnoid hemorrhage (SAH) in rabbits.

Methods.Intrathecal administration of MPL or DPL (5 µg/kg) was performed immediately before and 24 hours after induction of SAH in New Zealand White rabbits. Forty-eight hours after induction of SAH, the animals were killed by perfusion fixation for morphometric analyses of vessels or perfused with saline and assayed for superoxide dismutase (SOD) activity. Additional rabbits were administered MPL or DPL and killed 24 hours later for assessment of SOD activity; no SAH was induced in these animals.

Experimental SAH elicited spasm of the basilar arteries in each group. Vasospasm was markedly attenuated in animals treated with MPL (p < 0.01 compared with vehicle-treated animals), but not in animals treated with DPL. A substantial reduction in SOD activity in the basilar artery accompanied the vasospasm; this loss of activity was significantly blocked by treatment with MPL, but not DPL. In animals that were not subjected to experimental SAH, MPL elicited a significant increase in SOD activity over basal levels, whereas DPL was ineffective.

Conclusions.These data provide evidence of a marked protective effect of the endotoxin analog MPL against vasospasm. Although the mechanism(s) responsible for the protective effect of MPL remains to be verified, an enhancement of basal antioxidant activity and an inhibition of SAH-induced loss of this activity are attractive candidates. An MPL-based therapy could represent a useful addition to current therapies for SAH-induced cerebral injury.
Rerupture of coil-embolized aneurysm during long-term observation
Authors: Manabe Hiroshi , Fujita Seiichiro , Hatayama Toru , Suzuki Shigeharu , Yagihashi Soroku
Published: June 2009

✓ The authors describe the histopathological findings in a case involving rerupture of a recanalized aneurysm of the internal carotid artery 8 months after partial (95%) embolization with interlocking detachable coils. The aneurysm was filled with poorly organized thrombus, and its orifice was devoid of endothelial cells. It appears likely that a long period of observation may be required to confirm the complete thrombotic organization of coil-embolized aneurysms. This indicates that caution is needed because rupture may follow recanalization of the aneurysm.
Benign fibroosseous lesions involving the skull base, paranasal sinuses, and nasal cavity
Authors: Saito Kiyoshi , Fukuta Keizo , Takahashi Masakatsu , Seki Yukio , Yoshida Jun
Published: June 2009

✓ The authors report two patients with benign fibroosseous lesions involving the center of the skull base: a 15-year-old boy with repetitive meningitis and pneumocephalus and a 11-year-old boy with nasal obstruction and headache. The clinical diagnoses were ossifying fibroma and aneurysmal bone cyst, respectively. Lesions in both patients extended to the nasal cavity, the sphenoid and posterior ethmoid sinuses, and the skull base, where the planum sphenoidale, the sella turcica, the upper two-thirds of the clivus, and the medial portion of the middle cranial base were involved. The lesions were totally removed using an anterior craniofacial approach. Characteristics of these lesions and the surgical approach are discussed.
Long-term follow-up review of patients who underwent laminectomy for lumbar stenosis: a prospective study
Authors: Javid Manucher J. , Hadar Eldad J.
Published: June 2009

Object. Decompressive laminectomy for stenosis is the most common operation performed in the lumbar spine in older patients. This prospective study was designed to evaluate long-term results in patients with symptomatic lumbar stenosis.

Methods. Between January 1984 and January 1995, 170 patients underwent surgery for lumbar stenosis (86 patients), lumbar stenosis and herniated disc (61 patients), or lateral recess stenosis (23 patients). The male/female ratio for each group was 43:43, 39:22, and 14:9, respectively. The average age for all groups was 61.4 years. For patients with lumbar stenosis, the success rate was 88.1% at 6 weeks and 86.7% at 6 months. For patients with lumbar stenosis and herniated disc, the success rate was 80% at 6 weeks and 77.6% at 6 months, with no statistically significant difference between the two groups. For patients with lateral recess stenosis, the success rate was 58.7% at 6 weeks and 63.6% at 6 months; however, the sample was not large enough to be statistically significant. One year after surgery a questionnaire was sent to all patients; 163 (95.9%) responded. The success rate in patients with stenosis had declined to 69.6%, which was significant (p = 0.012); the rate for patients with stenosis and herniated disc was 77.2%; and that for lateral recess stenosis was 65.2%. Another follow-up questionnaire was sent to patients 1 to 11 years after surgery (average 5.1 years); 146 patients (85.9%) responded, 10 (5.9%) were deceased, and 14 (8.2%) were lost to follow-up review. At 1 to 11 years the success rate was 70.8% for patients with stenosis, 66.6% for those with stenosis and herniated disc, and 63.6% for those with lateral recess stenosis. Eleven patients who underwent reoperation were included in the group of patients whose surgeries proved unsuccessful, regardless of their ultimate outcome. There was no statistically significant difference in outcome between 1 year and 1 to 11 years with respect to stenosis, stenosis with herniated disc, and lateral recess stenosis.

Conclusions. In conclusion, long-term improvement after laminectomy was maintained in two-thirds of these patients.