bluuebunny/crossref_metadata_2025 huggingface dataset:
Indium-111 diethylene-triamine-pentaacetic acid scintigraphy in the evaluation of function and patency of baclofen intrathecal infusion systems
Authors: Pak Samuel , Jallo George I. , Biser Ann , Ziessman Harvey A.
Published: January 2008

Object

Baclofen pump infusion systems are used for the treatment of patients with severe spasticity. When symptoms do not respond to infusion rate increases, the cause may be pump malfunction or catheter obstruction. The purpose of this investigation was to review the authors' experience with indium-111 diethylene-triamine-pentaacetic acid (In-111 DTPA) scintigraphy for evaluation of baclofen infusion system function and patency and to correlate scintigraphic findings with patient treatment and outcome to determine optimal methodology and diagnostic criteria.

Methods

Ten scintigraphic studies acquired in eight patients (five adults, three adolescents) were retrospectively reviewed. Imaging was routinely performed at 4, 24, 48, and 72 hours after injection of In-111 DTPA into the pump reservoir. The results of the studies were interpreted by two nuclear medicine physicians who had no knowledge of the patients' clinical history or outcome. The scintigraphic findings (for example, radiotracer detected in the basal cisterns, cervical or thoracolumbar regions, infusion catheter, and pump) were recorded and correlated with neuroimaging findings, patient history, treatment, and clinical response to therapy.

Results

In cases in which the basal cistern could be visualized at any time and those in which radiotracer was visualized in the thoracolumbar intrathecal region within 48 hours, the pump systems were functional and symptoms responded to an increase in infusion rate. One patient in whom activity was visualized in the thoracolumbar intrathecal region by 72 hours also experienced clinical improvement with a flow rate increase. Visualization of the pump alone or only the pump and the subcutaneous catheter was consistent with catheter obstruction or pump malfunction.

Conclusion

The use of In-111 DTPA scintigraphy of intrathecal baclofen infusion systems can play an important role in determining the functional status of these systems and guiding subsequent patient care.
The Eastern heart and Galen's ventricle: a historical review of the purpose of the brain
Authors: Baig Mirza N. , Chishty Faheem , Immesoete Phillip , Karas Chris S.
Published: January 2008

✓The seat of consciousness has not always been thought to reside in the brain. Its “source” is as varied as the cultures of those who have sought it. At present, although most may agree that the central nervous system is held to be the root of individualism in much of Western philosophy, this has not always been the case, and this viewpoint is certainly not unanimously accepted across all cultures today.

In this paper the authors undertook a literary review of ancient texts of both Eastern and Western societies as well as modern writings on the organic counterpart to the soul. The authors have studied both ancient Greek and Roman material as well as Islamic and Eastern philosophy.

Several specific aspects of the human body have often been proposed as the seat of consciousness, not only in medical texts, but also within historical documents, poetry, legal proceedings, and religious literature. Among the most prominently proposed have been the heart and breath, favoring a cardiopulmonary seat of individualism. This understanding was by no means stagnant, but evolved over time, as did the role of the brain in the definition of what it means to be human.

Even in the 21st century, no clear consensus exists between or within communities, scientific or otherwise, on the brain's capacity for making us who we are. Perhaps, by its nature, our consciousness—and our awareness of our surroundings and ourselves—is a function of what surrounds us, and must therefore change as the world changes and as we change.
Decision making in head injury management in the Edwin Smith Papyrus
Authors: Sanchez Gonzalo Moreno , Burridge Alwyn Louise
Published: January 2008

✓The Edwin Smith Papyrus (circa 1650–1550 BC) is a didactic trauma treatise of major interest to neurosurgery, as it deals primarily with cranial and spine injuries. Information regarding the patient's condition is conveyed in the papyrus with sufficient clarity to allow a clinical assessment of each injury. The ancient Egyptian physician/teacher lists the key diagnostic elements in each case, and then pronounces his opinion of the treatment potential in one of three verdicts: 1) “a medical condition I can treat;” 2) “a medical condition I can contend with;” or 3) “a medical condition you will not be able to treat.” The structural organization of the text according to regional injuries of increasing severity permits analysis of sequential cases, and makes it possible to determine which clinical features led the ancient Egyptian physician to give the first or second verdict in the less severe injuries, but the third in the worst cases. Interestingly, the ancient physicians were not deterred from contending with injuries in the presence of basilar skull fractures, traumatic meningismus, skull perforation without overt neurological deficit, drowsiness, limited facial fractures, or closed head injuries without depressed fragments. Factors identified as determinant for the third verdict in head injuries are depressed skull fragments, dura laceration with exposed brain, infected cranial wounds/tetanus, major craniofacial fractures, deep skull–penetrating stab wounds, and aphasia. This study describes three case sequences of head injuries.
The management of cranial injuries in antiquity and beyond
Authors: Kshettry Varun R. , Mindea Stefan A. , Batjer H. Hunt
Published: January 2008

✓Cranial injuries were among the earliest neurosurgical problems faced by ancient physicians and surgeons. In this review, the authors trace the development of neurosurgical theory and practice for the treatment of cranial injuries beginning from the earliest ancient evidence available to the collapse of the Greco–Roman civilizations. The earliest neurosurgical procedure was trephination, which modern scientists believe was used to treat skull fractures in some civilizations. The Egyptian papyri of Edwin Smith provide a thorough description of 27 head injuries with astute observations of clinical signs and symptoms, but little information on the treatment of these injuries. Hippocrates offered the first classification of skull fractures and discussion of which types required trephining, in addition to refining this technique. Hippocrates was also the first to understand the basis of increased intracranial pressure. After Hippocrates, the physicians of the Alexandrian school provided further insight into the clinical evaluation of patients with head trauma, including the rudiments of a Glasgow Coma Scale. Finally, Galen of Pergamon, a physician to fallen gladiators, substantially contributed to the understanding of the neuroanatomy and physiology. He also described his own classification system for skull fractures and further refined the surgical technique of trephination. From the study of these important ancient figures, it is clearly evident that the knowledge and experience gained from the management of cranial injuries has laid the foundation not only for how these injuries are managed today, but also for the development of the field of neurosurgery.
Section of the terminal filum for occult tethered cord syndrome: toward a scientific answer
Authors: Steinbok Paul , MacNeily Andrew E.
Published: January 2008

✓The concept of an occult tethered cord syndrome (OTCS), in which a normally located conus is tethered by the terminal filum, is controversial. Children with OTCS typically present with neurogenic urinary incontinence that has been refractory to medical management. Authors of a number of case series have suggested that section of the terminal filum may improve urinary symptoms, but the quality of the evidence supporting this treatment is not good.

The literature related to OTCS is reviewed and the progress toward a randomized controlled trial to assess the value of filum section in OTCS is detailed. A scientific answer to the question of filum section for OTCS awaits the results of an ongoing pilot randomized controlled trial and a more definitive trial to follow.
Pathophysiology of tethered cord syndrome and similar complex disorders
Authors: Yamada Shokei , Won Daniel J. , Pezeshkpour Gholam , Yamada Brian S. , Yamada Shoko M. , Siddiqi Javed , Zouros Alexander , Colohan Austin R. T.
Published: January 2008

✓Tethered cord syndrome (TCS) is a stretch-induced functional disorder of the spinal cord due to the fact that its caudal portion is anchored by an inelastic structure. The functional lesion of TCS is generally situated in the lumbosacral cord, and many authors have shown that the syndrome is reversible via surgery to untether the cord. To clarify the expressions relevant to TCS, such as “cord tethering” and “tethered cord,” the authors have formulated three categories. These categories include cases that show the anatomical appearance of spinal cord stretching. Among them, Category 1 is isolated to represent the “true TCS.”

The authors focus their discussion of the pathophysiology of TCS on Category 1 to explain the impaired oxidative metabolism and electrophysiological derangements within the tethered spinal cord, which is the primary intrinsic cause of the dysfunction. Furthermore, they extend the discussion to the extrinsic (outside the spinal cord) factors and other complex conditions that mimic TCS.
Termination of the normal conus medullaris in children: a whole-spine magnetic resonance imaging study
Authors: Kesler Henry , Dias Mark S. , Kalapos Paul
Published: January 2008

Object

The mean level of the conus medullaris (CM) has been estimated to lie opposite the L1/2 disc space in several previous studies using ultrasound, CT myelography, and magnetic resonance (MR) imaging, but these studies have been limited in examining only the lumbar spine and including patients being evaluated for back pain and sciatica (creating a selection bias). Moreover, significant variability was found in the termination of the CM, with a small subset of subjects having a CM as low as the mid-body of L4. The authors sought to determine the normal level of the CM and its variability.

Methods

Children with brain or spinal cord tumors who underwent whole-spine surveillance MR imaging were identified retrospectively. The level of the CM was identified in each subject by counting down from C1. Vertebral anomalies, such as lumbarized S1, sacralized L5, or fewer rib-bearing segments, and the presence of fatty filum were noted.

Results

Findings regarding the level of termination of the CM were tightly grouped; the average was at the lower third of L1 and the mode of the distribution was at the L1/2 disc space, with very little variation. No CM ended below the mid-body of L2. The level of the CM was not significantly different among individuals with lumbarized or sacralized vertebrae or 11 rib-bearing segments.

Conclusions

The CM terminates most commonly at the L1–2 disc space and in the absence of tethering, the CM virtually never ends below the mid-body of L2. A CM that appears more caudal on neuroimages should be considered tethered.
Pediatric urodynamics: basic concepts for the neurosurgeon
Authors: Kitchens David M. , Anthony Herndon C. D. , Joseph David B.
Published: January 2008

✓ A great deal of information about overall bladder and urethral function can be obtained with the utilization of urodynamics. Urodynamics itself does not constitute a single test but more precisely the acquisition of multiple interconnected data combined to give an overall study of the storage and emptying phases of the bladder, function of the urethra, as well as the activity of the pelvic floor musculature. Urodynamic investigation represents one of the few reliable objective tests available to help guide therapy for the neurosurgeon. The authors review the various urodynamic tests most often utilized by pediatric urologists and discuss interpretation pitfalls with respect to interobserver variability. Technical aspects of the study are described along with normal and abnormal findings.
Posterior transpetrosal approach to aneurysms of the basilar trunk and vertebrobasilar junction
Authors: Seifert Volker , Stolke Dietmar
Published: January 2008

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.
Endoscopic endonasal transsphenoidal surgery: experience with 50 patients
Authors: Jho Hae-Dong , Carrau Ricardo L.
Published: January 2008

An endoscope was used in transsphenoidal surgery and eventually replaced the operating microscope as a tool for visualization. Initially four patients underwent operation via a sublabial transseptal approach using a rigid endoscope in conjunction with an operating microscope. The 48 subsequent operations were performed through a nostril using only rigid endoscopes. Forty-four patients had pituitary adenomas and six had various other lesions. Thirteen patients had microadenomas, 16 had intrasellar macroadenomas, nine had macroadenomas with suprasellar extension, and six had invasive macroadenomas involving the cavernous sinus. Among eight patients with Cushing's disease, seven were cured. Of 17 patients with prolactinomas, 10 were cured clinically and chemically. Among 19 patients with nonsecreting adenomas, 16 underwent total resection and three subtotal resection, with residual tumor in the cavernous sinus. Postoperatively all patients who had undergone endonasal endoscopic surgery had unobstructed nasal airways with minimal discomfort. More than half of the patients required only an overnight hospitalization.
Bromocriptine therapy for prolactin-secreting pituitary adenomas
Authors: Laws Edward R. , Thorner Michael O. , Vance Mary L.
Published: January 2008

An effective systematic approach for the management of prolactin-secreting pituitary adenomas is described. This methodology has stood the test of time and has been modified in accordance with experience. The primary goals are to obtain satisfactory control of the tumor and to avoid undesirable side effects related to dopamine agonist-based therapeutic agents.
Symptoms of pituitary apoplexy rapidly reversed with bromocriptine
Authors: Brisman Michael H. , Katz Gillian , Post Kalmon D.
Published: January 2008

Macroprolactinomas rarely present with apoplexy. The authors describe a patient with a macroprolactinoma who presented with apoplexy and rapid progression of a third nerve palsy. The patient was managed expectantly with bromocriptine therapy, and within 48 hours, the patient's third nerve palsy had completely resolved. The authors suggest that all patients who present with pituitary apoplexy in the presence of a pituitary tumor receive an immediate course of bromocriptine and steroid therapy until the prolactin level can be determined. Emergency surgery is indicated if visual function is abnormal and the tumor is not a prolactinoma.
Salvage chemotherapy for oligodendroglioma
Authors: Peterson Kendra , Paleologos Nina , Forsyth Peter , Macdonald David R. , Cairncross J. Gregory , _ _
Published: January 2008

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; second, the synergistic combination of VP-16 and CDDP may exert substantial antioligodendroglioma activity, and it warrants further evaluation.
The central sulcal vein: a landmark for identification of the central sulcus using functional magnetic resonance imaging
Authors: Yousry Tarek Ahmed , Schmid Urs Dieter , Schmidt Dorothea , Hagen Thomas , Jassoy Andre , Reiser Maximilian Friedrich
Published: January 2008

The authors evaluated the anatomical location of the central sulcus (CS) in 24 cerebral hemispheres (eight in which tumors were located centrally, 16 in controls) using: 1) classic anatomical landmarks seen on magnetic resonance (MR) imaging (24 hemispheres); 2) functional MR imaging (24 hemispheres); and 3) intraoperative electrical stimulation mapping (eight hemispheres). On MR imaging the CS was identified with certainty in 79% of hemispheres (four of eight in patients, 15 of 16 in controls). Functional MR imaging identified a parenchymal “motor hand area” in only 83% (20 of 24 hemispheres; five of eight in patients, 15 of 16 in controls); this area was located in the precentral gyrus in 16 (80%) of 20, additionally in the postcentral gyrus in 10 (50%) of 20, and exclusively in the postcentral gyrus in four (20%) of 20. In contrast, functional MR imaging detected one to three sulcal veins presumably draining blood from the adjacent motor hand area in 100% (24 of 24) of the hemispheres studied, and anatomical MR imaging and intraoperative mapping localized these veins in the CS. It is concluded that sulcal veins lying deep within the CS: 1) drain activated blood from the adjacent pre- or postcentral cortex during performance of a motor hand task; 2) can be identified easily with functional MR imaging; and 3) are an anatomical landmark for noninvasive indentification of the CS, and thus the sensorimotor strip. The detection of these veins provides a more consistent landmark than the detection of parenchymal motor areas by functional MR imaging; this technique may be used when classic anatomical landmarks fail to identify the sensorimotor strip.
Coil placement after clipping: endovascular treatment of incompletely clipped cerebral aneurysms
Authors: Forsting Michael , Albert Friedrich K. , Jansen Olav , von Kummer Rüdiger , Aschoff Alfred , Kunze Stefan , Sartor Klaus
Published: January 2008

In up to 4% of patients whose aneurysms are microsurgically clipped, there is an expected or unexpected aneurysm residuum. The authors describe two patients in whom surgical clipping did not result in complete obliteration of the aneurysm sac and in whom a second operation was not believed to be the solution to the problem. In both patients complete occlusion of the aneurysm residuum was achieved via an endovascular approach. Using the Guglielmi detachable coil system, it was possible to place two platinum coils selectively into the aneurysms. The endovascular approach may be a good treatment option for all patients in whom surgical clipping does not result in complete obliteration of the aneurysm sac and reoperation is contraindicated or unacceptable to the patient.
Progressive loss of glutamic acid decarboxylase, parvalbumin, and calbindin D28K immunoreactive neurons in the cerebral cortex and hippocampus of adult rat with experimental hydrocephalus
Authors: Tashiro Yuzuru , Chakrabortty Shushovan , Drake James M. , Hattori Toshiaki
Published: January 2008

The authors investigated functional neuronal changes in experimental hydrocephalus using immunohistochemical techniques for glutamic acid decarboxylase (GAD) and two neuronal calcium-binding proteins: parvalbumin (PV) and calbindin D28K (CaBP).

Hydrocephalus was induced in 16 adult Wistar rats by intracisternal injection of a kaolin solution, which was confirmed microscopically via atlantooccipital dural puncture. Four control rats received the same volume of sterile saline. Immunohistochemical staining for GAD, PV, and CaBP and Nissl staining were performed at 1, 2, 3, and 4 weeks after the injection. Hydrocephalus occurred in 90% of kaolin-injected animals with various degrees of ventricular dilation. In the cerebral cortex, GAD-, PV-, and CaBP-immunoreactive (IR) interneurons initially lost their stained processes together with a concomitant loss of homogeneous neuropil staining, followed by the reduction of their total number. With progressive ventricular dilation, GAD- and PV-IR axon terminals on the cortical pyramidal cells disappeared, whereas the number of CaBP-IR pyramidal cells decreased, and ultimately in the most severe cases of hydrocephalus, GAD, PV, and CaBP immunoreactivity was almost entirely diminished. In the hippocampus, GAD-, PV-, and CaBP-IR interneurons demonstrated a reduction of their processes and terminals surrounding the pyramidal cells, with secondary reduction of CaBP-IR pyramidal and granular cells. On the other hand, Nissl staining revealed almost no morphological changes induced by ischemia or neuronal degeneration even in the most severe cases of hydrocephalus.

Hydrocephalus results in the progressive functional impairment of GAD-, PV-, and CaBP-IR neuronal systems in the cerebral cortex and hippocampus, often before there is evidence of morphological injury. The initial injury of cortical and hippocampal interneurons suggests that the functional deafferentation from intrinsic projection fibers may be the initial neuronal event in hydrocephalic brain injury. Although the mechanism of this impairment is still speculative, these findings emphasize the importance of investigating the neuronal pathophysiology in hydrocephalus.
Functional localization of sensorimotor cortex by somatosensory evoked potentials produced by femoral nerve stimulation
Authors: Suzuki Akifumi , Yoshioka Kimio , Nishimura Hiromi , Yasui Nobuyuki
Published: January 2008

Cortical somatosensory evoked potentials (SSEPs) can be used to localize the central sulcus during a craniotomy. In particular, contralateral median nerve stimulation producing SSEPs can disclose the location of the central sulcus around the sensorimotor hand representation area. However, the median nerve cannot be stimulated in patients who undergo craniotomy at locations other than the hand representation area. The present study attempts to localize the central sulcus in the lateral surface of the brain near the interhemispheric fissure by stimulating the contralateral femoral nerve to produce SSEPs. Somatosensory evoked potentials were recorded between the superior lip of the interhemispheric fissure and 1.5 to 2 cm laterally in the cortex. Only seven of the 12 patients studied showed a phase reversal of the initial component across the central sulcus. The polarity was negative in the postcentral gyrus and positive in the precentral gyrus. The other five patients did not show a phase reversal of the initial component across the central sulcus. The amplitude was highest in the postcentral gyrus and the polarity was positive. Based on these results, the authors hypothesize that stimulating the contralateral femoral nerve to produce SSEPs and then analyzing the distribution of the SSEPs may provide a method for functional localization of the sensorimotor cortex around the interhemispheric fissure during craniotomy.
Subtemporal transparahippocampal amygdalohippocampectomy for surgical treatment of mesial temporal lobe epilepsy
Authors: Park T. S. , Bourgeois Blaise F. D. , Silbergeld Daniel L. , Dodson W. Edwin
Published: January 2008

Amygdalohippocampectomy (AH) is an accepted surgical option for treatment of medically refractory mesial temporal lobe epilepsy. Operative approaches to the amygdala and hippocampus that previously have been reported include: the sylvian fissure, the superior temporal sulcus, the middle temporal gyrus, and the fusiform gyrus. Regardless of the approach, AH permits not only extirpation of an epileptogenic focus in the amygdala and anterior hippocampus, but interruption of pathways of seizure spread via the entorhinal cortex and the parahippocampal gyrus. The authors report a modification of a surgical technique for AH via the parahippocampal gyrus, in which excision is limited to the anterior hippocampus, amygdala and parahippocampal gyrus while preserving the fusiform gyrus and the rest of the temporal lobe. Because transparahippocampal AH avoids injury to the fusiform gyrus and the lateral temporal lobe, it can be performed without intracarotid sodium amobarbital testing of language dominance and language mapping. Thus the operation would be particularly suitable for pediatric patients in whom intraoperative language mapping before resection is difficult.
Mechanisms of edema formation after intracerebral hemorrhage: effects of thrombin on cerebral blood flow, blood-brain barrier permeability, and cell survival in a rat model
Authors: Lee Kevin R. , Kawai Nobuyuki , Kim Seoung , Sagher Oren , Hoff Julian T.
Published: January 2008

Recently, the authors showed that thrombin contributes to the formation of brain edema following intracerebral hemorrhage. The current study examines whether the action of thrombin is due to an effect on cerebral blood flow (CBF), vasoreactivity, blood-brain barrier (BBB) function, or cell viability. In vivo solutions of thrombin were infused stereotactically into the right basal ganglia of rats. The animals were sacrificed 24 hours later; CBF and BBB permeability were measured. The actions of thrombin on vasoreactivity were examined in vitro by superfusing thrombin on cortical brain slices while monitoring microvessel diameter with videomicroscopy. In separate experiments C6 glioma cells were exposed to various concentrations of thrombin and lactate dehydrogenase release, a marker of cell death, was measured. The results indicate that thrombin induces BBB disruption as well as death of parenchymal cells, whereas CBF and vasoreactivity are not altered. The authors conclude that cell toxicity and BBB disruption by thrombin are triggering mechanisms for the edema formation that follows intracerebral hemorrhage.
Modified open-door cervical expansive laminoplasty for spondylotic myelopathy: operative technique, outcome, and predictors for gait improvement
Authors: Lee Thomas T. , Manzano Glen R. , Green Barth A.
Published: January 2008

Twenty-five patients underwent an expansive cervical laminoplasty for nontraumatic cervical spondylosis with myelopathy during the period from June 1990 to November 1994, and all had a minimum of 18 months of follow-up review. The open-door laminoplasty procedure presently reported consisted of the same approach evaluated by Hirabayashi in 1977, except that the authors of this report used three rib allografts to anchor the “open door,” rather than spinous process sutures or autologous bone grafts. Posterior foraminotomies and decompression were performed in patients with clinical radiculopathy and radiographic evidence of foraminal stenosis.

Preoperatively, gait disturbance was present in all patients. All 25 patients (100%) had long-tract signs on presentation. Nondermatomal upper-extremity symptoms (numbness, tingling, weakness, and pain) were quite common in this group of patients. Bowel, bladder, and/or sexual dysfunction was found in 13 (52%) of 25 patients. Preoperative radiographic studies showed a mean midline anteroposterior diameter spinal canal/vertebral body (SC/VB) ratio of 0.623 and a mean compression ratio (sagittal/lateral diameter ratio X 100%) of 37%.

This procedure was quite successful in relieving preoperative symptoms and few complications occurred. Gait disturbance was improved in 21 (84%) of 25 patients and hand numbness and tingling were improved in 13 (87%) of 15 patients. Bowel or bladder function improved in 10 (77%) of 13 patients. Radiculopathy, when present, was alleviated in all four patients after the decompressive procedure. The postoperative SC/VB ratio, as measured by plain lateral radiographs and/or computerized tomography scans, was improved to 0.871, a 38% improvement. In a comparison with the preoperative SC/VB ratio using the two-tailed t-test, alpha was less than 0.001. The compression ratio improved to 63% postoperatively, which yielded an alpha less than 0.005 according to the two-tailed t-test. Only one postoperative complication, an anterior scalene syndrome, was encountered.

Various predictors of surgical outcome based on gait improvement were evaluated. Age greater than 60 years at the time of presentation, duration of symptoms more than 18 months prior to surgery, preoperative bowel or bladder dysfunction, and lower-extremity dysfunction were found to be associated with poorer surgical outcome. Even when these conditions were present, gait improvement was noted in at least 70% of the patients.
Epilepsy surgery in children and adolescents
Authors: Laws Edward R. , Bertram Edward H.
Published: January 2008

There has been a considerable increase in interest in the surgical management of intractable epilepsy in children. Better methods of diagnosis and improved knowledge of natural history and results of surgery have been major factors in this phenomenon. The results of surgery in 76 patients who were 19 years of age or younger are reported. Success rates, defined as no postoperative seizures with loss of consciousness (Engel Grades I and II) were 78% in 52 patients treated by temporal lobectomy, 75% in eight patients who had extratemporal resections, 80% in 10 children treated by hemispherectomy, and 33% in three patients treated by corpus callosotomy.
Cerebral blood flow and temporal lobe epileptogenicity
Authors: Weinand Martin E. , Carter L. Philip , El-Saadany Waleed F. , Sioutos Panayiotis J. , Labiner David M. , Oommen Kalarickal J.
Published: January 2008

Long-term surface cerebral blood flow (CBF) monitoring was performed to test the hypothesis that temporal lobe epileptogenicity is a function of epileptic cortical perfusion. Forty-three bitemporal 2-hour periictal CBF studies were performed in 13 patients. Homotopic regions of temporal cortex maintained interictal epileptic cortical hypoperfusion and nonepileptic normal cortical CBF. At 10 minutes preictus, a statistically significant, sustained increase in CBF was detected on the epileptic temporal lobe. Two minutes preictus, there was approximation of CBF in the epileptic and nonepileptic temporal lobes. Thereafter, electrocorticographic (ECoG) and clinical seizure onset occurred. The linear relationship between CBF in the two hemispheres (epileptic and nonepileptic) was the inverse of normal (y = -0.347x + 62.767, r = 0.470, df = 95, p < 0.05). The data indicated a direct linear correlation between epileptic cortical CBF and seizure interval (frequency-1), a clinical measure of epileptogenicity (r = 0.610, df = 49, p < 0.05). Epileptogenicity was also found to be a logarithmic function of the difference between nonepileptic and epileptic cortical perfusion (r = 0.564, df = 58, t = 5.20, p < 0.05). The results showed that progressive hypoperfusion of the epileptic focus correlated with a decreased seizure interval (increased epileptogenicity). Increased perfusion of the epileptic focus correlated with an increased seizure interval (decreased epileptogenicity). The fact that CBF alterations precede ECoG seizure activity suggests that vasomotor changes may produce electrical and clinical seizure onset.
Transsulcal approach to mesiotemporal lesions
Authors: Germano Isabelle M.
Published: January 2008

Surgical resection of mesiotemporal lesions, particularly those in the dominant hemisphere, is often challenging. Standard approaches require excessive brain retraction, removal of normal cortex, or manipulation of the middle cerebral artery branches. This report describes a transsulcal temporal approach to mesiotemporal lesions and its application in three patients. Gross-total resection of the lesion was accomplished in all cases. An anatomical cadaveric study was also performed to delineate the microsurgical anatomy of this approach. Precise knowledge of temporal intraventricular landmarks allows navigation to the lesion without the need for a navigational system. This approach is helpful for neurologically intact patients with mesiotemporal lesions.
The suboccipital cavernous sinus
Authors: Arnautovic Kenan I. , Al-Mefty Ossama , Pait T. Glenn , Krisht Ali F. , Husain Muhammad M.
Published: January 2008

The authors studied the microsurgical anatomy of the suboccipital region, concentrating on the third segment (V3) of the vertebral artery (VA), which extends from the transverse foramen of the axis to the dural penetration of the VA, paying particular attention to its loops, branches, supporting fibrous rings, adjacent nerves, and surrounding venous structures.

Ten cadaver heads (20 sides) were fixed in formalin, their blood vessels were perfused with colored silicone rubber, and they were dissected under magnification. The authors subdivided the V3 into two parts, the horizontal (V3h) and the vertical (V3v), and studied the anatomical structures topographically, from the superficial to the deep tissues. In two additional specimens, serial histological sections were acquired through the V3 and its encircling elements to elucidate their cross-sectional anatomy. Measurements of surgically and clinically important features were obtained with the aid of an operating microscope.

This study reveals an astonishing anatomical resemblance between the suboccipital complex and the cavernous sinus, as follows: venous cushioning; anatomical properties of the V3 and those of the petrous-cavernous internal carotid artery (ICA), namely their loops, branches, supporting fibrous rings, and periarterial autonomic neural plexus; adjacent nerves; and skull base locations. Likewise, a review of the literature showed a related embryological development and functional and pathological features, as well as similar transitional patterns in the arterial walls of the V3 and the petrous-cavernous ICA. Hence, due to its similarity to the cavernous sinus, this suboccipital complex is here named the "suboccipital cavernous sinus." Its role in physiological and pathological conditions as they pertain to various clinical and surgical implications is also discussed.
Cervical spondylotic myelopathy: surgical decision making
Authors: Naderi Sait , Benzel Edward C. , Baldwin Nevan G.
Published: January 2008

Cervical spondylotic myelopathy can produce a variety of clinical signs and symptoms secondary to neural compromise and biomechanical involvement of the spine. The surgical treatment of cervical spondylotic myelopathy remains a controversial issue after many years of study, evolution, and refinement. Several ventral, dorsal, or combined approaches have been defined. The complications associated with ventral approaches and the concerns about kyphosis following dorsal approaches led to the development of a variety of laminoplasty procedures. This paper reviews the biomechanical basis of cervical spondylotic myelopathy and its effect on choosing the appropriate surgical approach.
Decompression via microsurgical anterior foraminotomy for cervical spondylotic myelopathy
Authors: Jho Hae-Dong
Published: January 2008

Over the past few years, a microsurgical anterior foraminotomy technique has been developed by the author and used to achieve spinal cord decompression for the treatment of cervical spondylotic myelopathy. A 5 X 8-mm unilateral anterior foraminotomy is accomplished by resecting the uncovertebral joint via an anterior approach. Through the foraminotomy hole, the posterior osteophytes at the spinal cord canal are removed diagonally up to the beginning of the contralateral nerve root. To treat multilevel disease, a tunnel is made among the foraminotomy holes. This technique accomplishes widening of the spinal cord canal in the transverse and longitudinal axes by direct resection of the compressive lesions through the holes of unilateral anterior foraminotomies; however, it does not require bone fusion or postoperative immobilization. Postoperatively patients remain in the hospital overnight, and do not need to wear cervical braces. This new surgical technique has shown excellent clinical outcomes with fast recovery and adequate anatomical decompression in patients with cervical spondylotic myelopathy. The surgical technique is reported and illustrated by two of the author's cases.
Cervical spondylotic myelopathy treated with corpectomy: technique and results in 44 patients
Authors: Naderi Sait , Alberstone Cary D. , Rupp Frederick W. , Benzel Edward C. , Baldwin Nevan G.
Published: January 2008

Forty-four patients with cervical spondylotic myelopathy who underwent a ventral surgical approach were evaluated with respect to the results of surgery. The neurological status of the patients was categorized according to the modified Japanese Orthopedic Association scale (0-18). Three patients had a functional score of 8, one patient 9, five patients 10, five patients 11, seven patients 12, seven patients 13, seven patients 14, and nine patients had a functional score of 15, preoperatively. Twenty-three patients underwent a one-level corpectomy, 15 patients a two-level corpectomy, and six patients underwent a three-level corpectomy. Forty-one (93.1%) of the 44 patients underwent ventral cervical plate fixation. Complications among the 44 patients included graft-and instrumentation-related complications in seven cases, iliac crest donor-site infection in three cases, and respiratory complications in three cases. The follow-up periods ranged between 7 and 60 months (mean 42.3 months). Overall, the fusion rate was 97.72%. Three patients showed no functional change (6.8%), two patients were worse (4.5%), and 39 patients (88.6%) showed functional improvement in their score between +1 and +6 points (mean 2.16 points). There was no statistically significant difference in the functional improvement score in patients younger or older than 60 years old. The mean improvement in the functional score was found to be +2.857 ± 1.352, +2.400 ± 1.454, and +0.5000 ± 1.871 following one-level corpectomy, two-level, and three-level corpectomies, respectively. There were statistically significant differences in the neurological improvement observed between patients with one-level corpectomy and three-level corpectomy (p < 0.01), as well as between those with two-level and three-level corpectomy (p < 0.05). There was no statistically significant difference in the neurological outcome between patients with one-level and two-level corpectomy (p > 0.05). The results of this study demonstrate a high rate of solid bone fusion and a high rate of functional (neurological) improvement. Five patients underwent reoperation, predominantly for instrumentation failure. The use of instrumentation dictates careful consideration of the risk/benefit ratio associated with its use in each case.
Vascular mechanisms in the pathophysiology of human spinal cord injury
Authors: Tator Charles H. , Koyanagi Izumi
Published: January 2008

Vascular injury plays an important role in the primary and secondary injury mechanisms that cause damage to the acutely traumatized spinal cord. To understand the pathophysiology of human spinal cord injury, the authors investigated the vascular system in three uninjured human spinal cords using silicone rubber microangiography and analyzed the histological findings related to vascular injury in nine acutely traumatized human spinal cords obtained at autopsy. The interval from spinal cord injury to death ranged from 20 minutes to 9 months. The microangiograms of the uninjured human cervical cords demonstrated new information about the sulcal arterial system and the pial arteries. The centrifugal sulcal arterial system was found to supply all of the anterior gray matter, the anterior half of the posterior gray matter, approximately the inner half of the anterior and lateral white columns, and the anterior half of the posterior white columns. Traumatized spinal cord specimens in the acute stage (3-5 days postinjury) showed severe hemorrhages predominantly in the gray matter, but also in the white matter. The white matter surrounding the hemorrhagic gray matter showed a variety of lesions, including decreased staining, disrupted myelin, and axonal and periaxonal swelling. The white matter lesions extended far from the injury site, especially in the posterior columns. There was no evidence of complete occlusion of any of the larger arteries, including the anterior and posterior spinal arteries and the sulcal arteries. However, occluded intramedullary veins were identified in the degenerated posterior white columns. In the chronic stage (3-9 months postinjury), the injured segments showed major tissue loss with large cavitations, whereas both rostral and caudal remote sites showed well-demarcated necrotic areas indicative of infarction mainly in the posterior white columns. Obstruction of small intramedullary arteries and veins by the initial mechanical stress or secondary injury mechanisms most likely produced these extensive white matter lesions. Our studies implicate damage to the anterior sulcal arteries in causing the hemorrhagic necrosis and subsequent central myelomalacia at the injury site in acute spinal cord injury in humans.
Spinal cord stimulation with percutaneous and plate electrodes: side effects and quantitative comparisons
Authors: North Richard B. , Lanning Amy , Hessels Ryan , Cutchis Protagoras N.
Published: January 2008

Spinal cord stimulation is limited by the uncomfortable side effects experienced by the patient as the amplitude of stimulation is increased. These side effects include local segmental paresthesias or motor responses, which are objectively demonstrable as frequency-following muscle contractions, attributable to dorsal root stimulation. The authors present evidence for another mechanism of stimulation-evoked discomfort, namely recruitment of small fibers in ligamentum flavum, which occurs when electrodes are inserted percutaneously and their contacts are exposed circumferentially; this does not occur with plate electrodes with insulated dorsal surfaces.

In a consecutive series of 79 patients with postsurgical lumbar pain syndromes, percutaneous four-contact electrodes were tested at levels from T-8 through T-12. At one or more levels, 46% of patients described paravertebral, nonradiating discomfort, unaccompanied by frequency-following muscle contractions. This was observed most commonly at the T-8 and T-9 levels. The effect was ameliorated in some cases by using multiple cathodes in parallel, which reduced the current density at individual contacts.

In 10 of these patients, this side effect interfered with an otherwise successful trial to such a degree that an insulated plate electrode was selected for permanent implantation at the same level as the percutaneous electrode. This eliminated the uncomfortable side effect completely in all patients. Intraoperative testing with the insulated plate electrode inverted (that is, contacts dorsal) reproduced the side effect in the majority of patients, indicating that structures dorsal to the electrode, such as fibers in ligamentum flavum, mediate the effect. Postoperative testing by computerized techniques demonstrated improved coverage of pain by stimulation paresthesias, with lower stimulation power requirements, using the insulated plate electrode.

This technical limitation of percutaneous spinal cord stimulation electrodes, which may confound treatment if unrecognized, has been found to have a straightforward solution which indicates the underlying mechanism.
Computerized tomography-guided percutaneous bilateral selective cordotomy
Authors: Kanpolat Yücel , Savas Ali , Çaglar Sükrü , Temiz Cüneyt , Akyar Serdar
Published: January 2008

Percutaneous bilateral cordotomy performed using conventional techniques may cause the patient to develop sleep-induced apnea due to bilateral destruction of the ventrolateral reticulospinal tract. Computerized tomography (CT)-guided percutaneous cordotomy using a newly designed needle electrode system has the advantages of safe, selective, and controlled lesioning under direct visualization in the lateral spinothalamic tract. Given its low complication rate, bilateral selective cordotomy performed with CT guidance using this new needle electrode system may prove to be the treatment of choice for cancer patients with bilateral pain of the lower trunk and extremities.

The present series included five cancer patients suffering from intractable pain bilaterally in the lower trunk and extremities. All were treated with CT-guided bilateral selective cordotomy: the results demonstrate that this technique may be used effectively and safely.