bluuebunny/crossref_metadata_2025 huggingface dataset:
Nerve transfers for severe brachial plexus injuries: a review
Authors: Midha Rajiv
Published: January 2008

Nerve transfer procedures are increasingly performed for repair of severe brachial plexus injury (BPI), in which the proximal spinal nerve roots have been avulsed from the spinal cord. The procedure essentially involves the coaption of a proximal foreign nerve to the distal denervated nerve to reinnervate the latter by the donated axons. Cortical plasticity appears to play an important physiological role in the functional recovery of the reinnervated muscles. The author describes the general principles governing the successful use of nerve transfers. One major goal of this literature review is to provide a comprehensive survey on the numerous intra- and extraplexal nerves that have been used in transfer procedures to repair the brachial plexus. Thus, an emphasis on clinical outcomes is provided throughout. The second major goal is to discuss the role of candidate nerves for transfers in the surgical management of the common severe brachial plexus problems encountered clinically. It is hoped that this review will provide the treating surgeon with an updated list, indications, and expected outcomes involving nerve transfer operations for severe BPIs.
Restoration of hand function and so called “breathing arm” after intraspinal repair of C5–T1 brachial plexus avulsion injury
Authors: Carlstedt Thomas , Anand Praveen , Htut Min , Misra Peter , Svensson Mikael
Published: January 2008

This 9-year-old boy sustained a complete right-sided C5–T1 brachial plexus avulsion injury in a motorcycle accident. He underwent surgery 4 weeks after the accident. The motor-related nerve roots in all parts of the avulsed brachial plexus were reconnected to the spinal cord by reimplantation of peripheral nerve grafts. Recovery in the proximal part of the arm started 8 to 10 months later. Motor function was restored throughout the arm and also in the intrinsic muscles of the hand by 2 years postoperatively. The initial severe excruciating pain, typical after nerve root avulsions, disappeared completely with motor recovery. The authors observed good recruitment of regenerated motor units in all parts of the arm, but there were cocontractions. Transcranial magnetic stimulation produced response in all muscles, with prolonged latency and smaller amplitude compared with the intact side. There was inspiration-evoked muscle activity in proximal arm muscles—that is, the so-called “breathing arm” phenomenon. The issues of nerve regeneration after intraspinal reimplantation in a young individual, as well as plasticity and associated pain, are discussed.

To the best of the authors' knowledge, the present case demonstrates, for the first time, that spinal cord surgery can restore hand function after a complete brachial plexus avulsion injury.
Conus medullaris and cauda equina syndrome as a result of traumatic injuries: management principles
Authors: Harrop James S. , Hunt Gabriel E. , Vaccaro Alexander R.
Published: January 2008

Conus medullaris syndrome (CMS) and cauda equina syndrome (CES) are complex neurological disorders that can be manifested through a variety of symptoms. Patients may present with back pain, unilateral or bilateral leg pain, paresthesias and weakness, perineum or saddle anesthesia, and rectal and/or urinary incontinence or dysfunction. Although patients typically present with acute disc herniations, traumatic injuries at the thoracolumbar junction at the terminal portion of the spinal cord and cauda equina are also common. Unfortunately, a precise understanding of the pathophysiology and optimal treatments, including the best timing of surgery, has yet to be elucidated for either traumatic CES or CMS. In this paper the authors review the current literature on traumatic conus medullaris and cauda equina injuries and available treatment options.
Neuroendoscope-assisted evacuation of large intracerebral hematomas: introduction of a new, minimally invasive technique
Authors: Bakshi Ajay , Bakshi Asha , Banerji Ajit Kumar
Published: January 2008

Object

The aim of this study was to describe a new, minimally invasive technique for the endoscopic evacuation of intracerebral hematomas (ICHs) and the clinical and radiological outcomes in patients who underwent the procedure. The authors used a multifunctional three-in-one endoscopic instrument that combines a 0°, 4-mm rigid telescope, an irrigation cannula, and a cautery electrode.

Methods

In 13 patients a small keyhole craniotomy was made through noneloquent cortex to gain access to the hematoma. After opening the dura mater, a small cortical tunnel (~6 mm in diameter) was created using bipolar forceps and suction to enter into the clot. The three-in-one endoscope was then introduced to provide illumination and irrigation inside the cavity. The clot was safely aspirated under endoscopic vision and constant irrigation by performing microsurgical suction with the other hand. Hemostasis could be achieved using electrocautery and Surgicel. This technique eliminates the use of an endoscopic sheath, thus providing more maneuverability to the neurosurgeon. The brilliant illumination provided by the endoscope and the possibility of using electrocautery in the depths of the brain combined with the increased maneuverability make this technique valuable. Near-complete hematoma evacuation was achieved in 11 (85%) of 13 patients. There were four deaths (30%).

Conclusions

Safe and effective evacuation of large ICHs is possible by using the three-in-one endoscopic device. Appropriate indications for surgery in patients with large intracerebral hemorrhage must be developed.
Comparison of pallidal and subthalamic deep brain stimulation for the treatment of levodopa-induced dyskinesias
Authors: Follett Kenneth A.
Published: January 2008

Deep brain stimulation (DBS) can relieve dyskinesias effectively and safely. This modality is applied most commonly in the treatment of dyskinesias associated with levodopa therapy for Parkinson disease. The subthalamic nucleus (STN) and globus pallidus internus (GPi) are the most common surgical targets. Deep brain stimulation of the GP has a direct antidyskinetic effect, whereas relief of dyskinesias by DBS of the STN depends on postoperative reduction of dopaminergic medications. Outcomes are similar for DBS in these two sites despite the different mechanisms by which the stimulation relieves dyskinesias. Deep brain stimulation of the STN has become the surgical treatment of choice in many movement disorders programs but this modality has not been compared with DBS of the GPi in randomized controlled trials, and the superiority of one site over the other remains unproven. In the absence of data demonstrating superiority, selection of the stimulation target should be individualized to meet the needs of each patient. Selection of the target should be based on the patient's most disabling symptoms, response to medications (including side effects), and the goals of therapy, with consideration given to the different antidyskinetic effects of DBS of the STN and GPi.
Intradural ventral and ventrolateral tumors of the spinal cord: surgical treatment and results
Authors: Slin'ko Eugene I. , Al-Qashqish Iyad Ischak
Published: January 2008

Object

To improve results of surgical treatment of ventral and ventrolateral tumors of the spinal cord, the authors analyzed surgical approaches, defined the indications for various approaches, and assessed the clinical results.

Methods

Between 1993 and 2004 the authors treated 360 patients: 43 of them had dorsal, 177 dorsolateral, 33 ventral, and 107 had ventrolateral intradural extramedullary tumors. Among 140 patients with intradural extramedullary ventral and ventrolateral tumors, neuromas were seen in 56 and meningiomas in 84. Of the 140 patients studied, tumors were removed totally in 102 (74%), subtotally in 30 (21%), and partially in eight (5%). After ventrolateral and dorsolateral approaches were introduced in 1996, tumors in ventral or ventrolateral locations have been removed totally or subtotally. In the group of patients with meningiomas, 41 of the lesions were the meningothelial type, 22 were transitional, 12 fibroblastic, four psammomatous, three were angiomatous, one was atypical, and one was malignant. Tumors in the neuroma group were schwannomas in 45 patients and neurofibromas in 11. Postoperatively, recovery was observed in 70 patients (50%), improvement in 53 (38%), no change in 10 (7%), and deterioration in seven (5%). At follow-up evaluation recovery was noted in 76 patients, improvement in 58, no change in four, and in two patients the neurological symptoms were worse than before the operation.

Conclusions

Surgical routes to extramedullary tumors should be chosen based on the location of the tumor, its spread, and the region in which it is localized.
Complete resection of a complex glomus jugulare tumor with extensive venous involvement
Authors: Prabhu Sujit S. , DeMonte Franco
Published: January 2008

The authors describe a case of a complex glomus jugulare tumor with extensive involvement of the venous system. The entire left internal jugular vein up to its innominate insertion was involved with tumor, with proximal extension to the sigmoid sinus, transverse sinus, and the torcular herophili. Gross-total resection of the tumor required a two-stage median sternotomy. This is the first case report of a glomus jugulare tumor in which there was such extensive involvement of the venous system, requiring a multidisciplinary team approach for complete resection.
The microsurgical anatomy of the glossopharyngeal nerve with respect to the jugular foramen lesions
Authors: Özveren Mehmet Faik , Türe Uđur
Published: January 2008

Removal of lesions involving the jugular foramen region requires detailed knowledge of the anatomy and anatomical landmarks of the related area, especially the lower cranial nerves. The glossopharyngeal nerve courses along the uppermost part of the jugular foramen and is well hidden in the deep layers of the neck, making this nerve is the most difficult one to identify during surgery. It may be involved in various pathological entities along its course. The glossopharyngeal nerve can also be compromised iatrogenically during the surgical treatment of such lesions. The authors define landmarks that can help identify this nerve during surgery and discuss the types of lesions that may involve each portion of the glossopharyngeal nerve.
The future of spinal arthroplasty: a biomaterial perspective
Authors: Oskouian Rod J. , Whitehill Richard , Samii Amir , Shaffrey Mark E. , Johnson J. Patrick , Shaffrey Christopher I.
Published: January 2008

Both total hip and knee arthroplasty have demonstrated outstanding clinical results. The functional spinal unit composed of the intervertebral disc and facet joints is at least as complex. The intricacies of the coupled motions of the functional spinal unit have made development of an artificial disc a challenge. There have been several failed attempts to create a disc replacement that recapitulates normal motion while providing significant longevity and a low incidence of complications.

Better understanding of the biomechanics of the intervertebral disc complex and improvements in implant material have made successful intervertebral disc replacement a likely reality, now that several artificial discs have completed Food and Drug Administration clinical trials. In this manuscript the authors detail the biomaterials used in disc arthroplasty and discuss joint wear and the host response to wear debris.
Prophylaxis for deep venous thrombosis in patients with craniotomies: a review
Authors: Danish Shabbar F. , Burnett Mark G. , Stein Sherman C.
Published: January 2008

Deep venous thrombosis (DVT) remains a source of significant morbidity and mortality in patients who undergo craniotomy procedures. Despite several studies in which the safety and efficacy of various prophylactic strategies were examined, there is still no consensus among clinicians. In this paper the authors review the literature with regard to epidemiological and pathophysiological features, screening methods, and prophylactic measures for DVT.
Intramedullary spinal cord ganglioglioma presenting with abnormal abdominal wall movement
Authors: Aslanabadi Saeid , Azhough Ramin , Motlagh Parviz Samad , Hadidchi Shahram , Tabrizi Ali Dastranj , Zonouzy Keivan Kashy
Published: January 2008

The authors present a case of intramedullary ganglioglioma in a 6-year-old girl. Since the age of 4 months the patient had experienced a spontaneous wavy undulating movement of her anterior abdominal wall resembling a severe peristalsis. The movement was continuous even during sleep, and this symptom was named “belly dance.” Magnetic resonance images revealed an intramedullary tumor with ill-defined borders, and the lesion was partially resected. The patient made a good recovery, although 4 years postsurgery her scoliosis had progressed.
Current treatment options for unruptured intracranial aneurysms
Authors: Chen Peng Roc , Frerichs Kai , Spetzler Robert
Published: January 2008

A patient with an unruptured intracranial aneurysm has three options: surgical clip placement, endovascular coil occlusion, and observation. The decision making about management of these lesions should be based on the risk of aneurysm rupture and the risks associated with surgical or endovascular intervention. For patients who require interventions, factors such as aneurysm recurrence rate, its location, surgical or endovascular accessibility, the patient's general medical condition, and the individual's treatment preference should be taken into account to determine the choice of therapies. Currently, a team approach by neurosurgeons and endovascular interventionists is recommended to evaluate each patient and to tailor the best treatment plan.
Spinal subdural empyema after a dural tear
Authors: Wu Adam S. , Griebel Robert W. , Meguro Kotoo , Fourney Daryl R.
Published: January 2008

Spinal subdural empyema is an exceptionally rare and serious condition. Immediate surgery with complete exposure and drainage of the abscess is generally recommended. The authors present a patient in whom a Staphylococcus aureus septicemia related to nosocomial pneumonia developed after a thoracic laminectomy. The surgery was further complicated by an unintended durotomy (dural tear). Ten days postoperatively, the patient experienced back pain and lower-extremity symptoms caused by a subdural empyema. Cultures from the wound also grew S. aureus. This represents the first case of spinal subdural empyema in which the spread of infection into the subdural space is believed to have been facilitated by a dural tear. The patient had a favorable outcome despite an initial delay in surgical intervention because of a pulmonary embolus.
Instrumentation in patients with spinal infection
Authors: Lee Max C. , Wang Michael Y. , Fessler Richard G. , Liauw Jason , Kim Daniel H.
Published: January 2008

Object

Placement of instrumentation in the setting of a spinal infection has always been controversial. Although the use of allograft and autograft bone has been accepted as safe, demonstrations of the effectiveness of titanium have been speculative, based on several retrospective reviews. The authors' goal in this study was to demonstrate the effectiveness of instrumentation in the setting of a spinal infection by retrospectively reviewing their cases over the last 4 years and searching the literature regarding instrumentation in patients with pyogenic spinal infections.

Methods

The authors conducted a retrospective review of their cumulative data on spinal infections. Diagnosis was based on subjective and objective clinical findings, along with radiographic and laboratory evaluation of infection and mechanical stability. Patients with medically managed disease and those who did not receive instrumentation were eliminated from this review.

Of 105 patients with spinal infections who were admitted to the neurosurgical service between January 2000 and June 2004, 30 underwent surgical debridement necessitating spinal instrumentation. There were 17 women and 13 men in this group ranging from 28 to 86 years of age. Follow-up duration ranged from 3 to 54 months. There was one death, which occurred 3 months postsurgery. In three patients a deep wound infection developed, necessitating intervention, and two patients experienced a graft expulsion. Twenty-nine patients went on to demonstrate adequate fusion based on follow-up neuroimaging studies.

Conclusions

The goal of neurosurgical intervention in the setting of spinal infection is to obtain an organism culture and the debridement of infection while maintaining neurological and mechanical stability. The authors demonstrate the effectiveness of radical debridement of infected bone and placement of instrumentation in patients with spinal infections.
Update on current registries and trials of carotid artery angioplasty and stent placement
Authors: Das Sunit , Bendok Bernard R. , Getch Christopher C. , Awad Issam A. , Batjer H. Hunt
Published: January 2008

Stroke remains the leading cause of disability in adults and the third leading cause of death in the US. Carotid artery (CA) occlusive disease is the primary pathophysiological source of 10 to 20% of all strokes. Carotid endarterectomy (CEA) has been shown to reduce the risk of stroke in patients with both symptomatic and asymptomatic extracranial CA stenosis. Carotid artery angioplasty and stent placement has recently emerged as an alternative to CEA for primary and secondary prevention of stroke related to CA stenosis. With the advent of the embolic protection device, the safety of CA angioplasty and stent placement has approached, if not surpassed, that of CEA. In particular, the former has come to be considered as a first-line therapy in the management of CA stenotic disease in individuals at high risk for complications related to surgical intervention. Preliminary data from multiple registries have demonstrated that CA angioplasty and stent placement is an effective means of treating CA stenosis. The results of the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy trial have demonstrated that this modality has a significant role in the management of CA disease in symptomatic and asymptomatic patients with risk factors for high rates of surgery-related morbidity or mortality. With the completion of the Carotid Revascularization Endarterectomy versus Stent Trial, the role of CA angioplasty and stent placement in the prevention of stroke in all individuals with significant CA stenosis should be better demarcated. This treatment modality promises to assume a central role in stroke prophylaxis in patients with CA disease who are at high risk for complications related to surgery.
The natural history of intracranial carotid artery atherosclerosis
Authors: Komotar Ricardo J. , Mocco J , Wilson David A. , Connolly E. Sander , Lavine Sean D. , Meyers Philip M.
Published: January 2008

Intracranial atherosclerosis is the cause of a significant number of strokes. Despite maximal medical therapy, this disease continues to carry a poor prognosis. The authors reviewed studies in which the outcomes after conservative management in patients with intracranial carotid artery atherosclerosis were reported. Analysis of the literature demonstrates that maximal medical therapy frequently fails with this disease, leaving patients at high risk for cerebral infarction and death. A better understanding of the pathophysiological aspects and natural history of this condition may serve to guide clinical decision making and the choice of therapeutic options in this patient population.
Carotid artery angioplasty and stent placement for recurrent stenosis
Authors: Koebbe Christopher J. , Liebman Kenneth , Veznedaroglu Erol , Rosenwasser Robert
Published: January 2008

Object

The use of endovascular management for recurrent carotid artery (CA) stenosis is rapidly expanding due to the increased surgical risk associated with repeated carotid endarterectomy (CEA). Carotid artery angioplasty and stent placement for recurrent CA stenosis offers a less invasive strategy with fewer procedural complications and may provide a more durable treatment. The authors report on their experience with this procedure in the management of recurrent CA stenosis.

Methods

A retrospective review was performed to evaluate clinical and ultrasound imaging outcomes after CA angioplasty and stent placement. Twenty-three vessels in 22 patients with severe recurrent stenosis (> 80%) post-CEA were treated with balloon angioplasty and stent placement without distal protection. There were no perioperative neurological or cardiac complications in this series. Over a mean follow-up period of 36 months, one patient (5%) suffered recurrent stenosis requiring retreatment with angioplasty alone.

Conclusions

The use of CA angioplasty and stent placement provides a safe and effective treatment for recurrent CA stenosis. The use of drug-eluting and/or bioactive stents in the future will likely further improve the efficacy of this procedure for recurrent CA stenosis.
Treatment of wide-necked cerebral aneurysms with the Neuroform2 Treo stent
Authors: Sani Sepehr , Jobe Kirk W. , Lopes Demetrius K.
Published: January 2008

Object

Until recently, wide-necked aneurysms were not considered amenable to treatment with coil embolization. The recent introduction of intracranial stents has provided a method of preventing coil migration out of wide-necked aneurysms. The Neuroform2 Treo is a modification of the Neuroform stent; the new version has a higher metal/artery ratio. The authors' initial experience with the use of this stent in combination with coil embolization to treat wide-necked intracranial aneurysms is reported and technical considerations are discussed.

Methods

The authors' first 10 consecutive patients with wide-necked intracranial aneurysms were included in this study. Inclusion criteria restricted the group to adult patients with wide-necked intracranial aneurysms (ruptured and unruptured lesions). A wide neck was defined as a dome/neck ratio of less than 2 or a neck that was 4 mm or wider as measured on angiograms. Immediate postprocedure angiography studies were performed to determine successful coil occlusion of the aneurysm as well as patency of the parent vessel. Six-month follow-up angiograms were obtained in all patients.

Ten aneurysms with poor dome/neck ratios (< 2) were studied in 10 patients. In all cases the stent was delivered to the aneurysm site and positioned without difficulty. No branch artery compromise was observed. A technical difficulty occurred in one case, with prolapse of a coil into the parent vessel, which was successfully corrected with no adverse clinical effects. There were no clinical or neurological complications associated with endovascular treatment of aneurysms in this series. One patient required further coil embolization because of findings on the 6-month follow-up cerebral angiogram.

Conclusions

The Neuroform2 Treo navigates similarly to the Neuroform2, with the advantage of increased aneurysm neck coverage. This feature may lower the retreatment rates for wide-necked cerebral aneurysms.
Determination of filling volumes in HydroCoil-treated aneurysms by using three-dimensional computerized tomography angiography
Authors: Deshaies Eric M. , Bagla Sandeep , Agner Celso , Boulos Alan S.
Published: January 2008

Object

Coil embolization of aneurysms has been shown to be as safe and effective as surgical clip ligation, but has a higher recurrence rate. Advances in coil technology aim to reduce aneurysm recurrence by coating the devices with biological substances. An example of this is MicroVention's HydroCoil, which is a platinum coil coated with hydro-gel that improves filling volumes by swelling when it contacts blood. The goal of this study was to determine whether this new coil type significantly reduced or prevented recurrences of aneurysms.

Methods

The authors used three-dimensional computerized tomography angiography to determine aneurysm volumes accurately in 12 patients prior to coil embolization. The percentage filling volume was subsequently calculated for each aneurysm after treatment with HydroCoils and the immediate and 6-month follow-up angiographically confirmed occlusions were evaluated. The data demonstrated that both anterior and posterior intracranial aneurysms with diameters of 3 to 25 mm and volumes of 0.03 to 4.8 ml had filling volumes of 0.02 to 1.36 ml, resulting in filling volumes from 23% in a giant ophthalmic artery aneurysm to 80% in a small anterior communicating artery aneurysm. All of the aneurysms except for the giant one demonstrated stable occlusion on angiographic studies obtained at the 6-month follow-up review.

Conclusions

HydroCoil embolization of intracranial aneurysms is safe and effective for small, large, and very large aneurysms. The percentage filling volume is greater than that reported for bare platinum coils in every case except the giant aneurysm. Nevertheless, angiographically confirmed occlusion is not directly related to percentage filling volume, but rather to the ability to occlude the aneurysm neck.
History of acoustic neurinoma surgery
Authors: Machinis Theofilos G. , Fountas Kostas N. , Dimopoulos Vassilios , Robinson Joe Sam
Published: January 2008

The purpose of this article is to provide insight into the development of surgery for acoustic neurinomas throughout the years. The significant contribution of surgical authorities such as Cushing, Dandy, and House are discussed. The advances in surgical techniques from the very first operations for acoustic tumors at the end of the 19th century until today are described, with special emphasis on the technological and diagnostic milestones that preceded each step of this development.
Lucien J. Rubinstein: enduring contributions to neuro-oncology
Authors: Mut Melike , Lopes M. Beatriz S. , Shaffrey Mark
Published: January 2008

Dr. Lucien Rubinstein is best remembered for his significant contributions to the field of neuropathology, particularly in the classification of nervous system tumors. His accomplishments in basic neuro-oncology and in the formulation of diagnostic principles reflected a unique talent for synthesizing fundamental clinicopathological concepts based on skillful diagnostic investigation and a thorough understanding of neurobiology. Dr. Rubinstein was the leader in the establishment of cell cultures from central nervous system (CNS) tumors. He meticulously analyzed both light and electron microscopic features of CNS tumors, recorded his findings, and patiently drew sketches to be shared generously with his colleagues and students. As a pioneer in neuropathology, in his work Dr. Rubinstein set the foundation for many enduring concepts in neurosurgery, neuro-oncology, neurology, and basic tumor biology.
CyberKnife radiosurgery for idiopathic trigeminal neuralgia
Authors: Lim Michael , Villavicencio Alan T. , Burneikiene Sigita , Chang Steven D. , Romanelli Pantaleo , McNeely Lee , McIntyre Melinda , Thramann Jeffrey J. , Adler John R.
Published: January 2008

Object

Gamma knife surgery is an accepted treatment option for trigeminal neuralgia (TN). The safety and efficacy of CyberKnife radiosurgery as a treatment option for TN, however, has not been established.

Methods

Forty-one patients were treated between May 2002 and September 2004 for idiopathic TN at Stanford University and the Rocky Mountain CyberKnife Center. Patients with atypical pain, multiple sclerosis, or previous radiosurgical treatment or a follow-up duration of less than 6 months were excluded. Patients were evaluated for the level of pain control, response rate, time to pain relief, occurrence of hypesthesia, and time to pain recurrence with respect to the length of the nerve treated and the maximum and the minimum dose to the nerve margin.

Thirty-eight patients (92.7%) experienced initial pain relief at a median of 7 days after treatment (range < 24 hours–4 months). Pain control was ranked as excellent in 36 patients (87.8%), moderate in two (4.9%), and three (7.3%) reported no change. Six (15.8%) of the 38 patients with initial relief experienced a recurrence of pain at a median of 6 months (range 2–8 months). Long-term response after a mean follow-up time of 11 months was found in 32 (78%) of 41. Twenty-one patients (51.2%) experienced numbness after treatment.

Conclusions

CyberKnife radiosurgery for TN has high rates of initial pain control and short latency to pain relief compared with those reported for other radiosurgery systems. The doses used for treatment were safe and effective. Higher prescribed doses were not associated with improvement in pain relief or recurrence rate. The hypesthesia rate was related to the length of the trigeminal nerve treated.
Trigeminal neuralgia: definition and classification
Authors: Eller Jorge L. , Raslan Ahmed M. , Burchiel Kim J.
Published: January 2008

Based on specific, objective, and reproducible criteria, a classification scheme for trigeminal neuralgia (TN) and related facial pain syndromes is proposed. Such a classification scheme is based on information provided in the patient's history and incorporates seven diagnostic criteria, as follows. 1) and 2) Trigeminal neuralgia Types 1 and 2 (TN1 and TN2) refer to idiopathic, spontaneous facial pain that is either predominantly episodic (as in TN1) or constant (as in TN2) in nature. 3) Trigeminal neuropathic pain results from unintentional injury to the trigeminal nerve from trauma or surgery. 4) Trigeminal deafferentation pain results from intentional injury to the nerve by peripheral nerve ablation, gangliolysis, or rhizotomy in an attempt to treat either TN or other related facial pain. 5) Symptomatic TN results from multiple sclerosis. 6) Postherpetic TN follows a cutaneous herpes zoster outbreak in the trigeminal distribution. 7) The category of atypical facial pain is reserved for facial pain secondary to a somatoform pain disorder and requires psychological testing for diagnostic confirmation. The purpose of a classification scheme like this is to advocate a more rigorous, standardized natural history and outcome studies for TN and related facial pain syndromes.
Technique of microvascular decompression
Authors: Jannetta Peter J. , Mclaughlin Mark R. , Casey Kenneth F.
Published: January 2008

Vascular compression of the trigeminal nerve in the cerebellopontine angle is now generally accepted as the primary source or “trigger” causing trigeminal neuralgia. A clear clinicopathological association exists in the neurovascular relationship. In general, pain in the third division of the trigeminal nerve is caused by rostral compression, pain in the second division is caused by medial or more distant compression, and pain in the first division is caused by caudal compression.

This discussion of the surgical technique includes details on patient position, placement of the incision and craniectomy, microsurgical exposure of the supralateral cerebellopontine angle, visualization of the trigeminal nerve and vascular pathological features, microvascular decompression, and wound closure. Nuances of the technique are best learned in the company of a surgeon who has a longer experience with this procedure.
Assessment of pain control, quality of life, and predictors of success after gamma knife surgery for the treatment of trigeminal neuralgia
Authors: Jawahar Ajay , Wadhwa Rishi , Berk Caglar , Caldito Gloria , Delaune Allyson , Ampil Federico , Willis Brian , Smith Donald , Nanda Anil
Published: January 2008

Object

There are various surgical treatment alternatives for trigeminal neuralgia (TN), but there is no single scale that can be used uniformly to assess and compare one type of intervention with the others. In this study the objectives were to determine factors associated with pain control, pain-free survival, residual pain, and recurrence after gamma knife surgery (GKS) treatment for TN, and to correlate the patients' self-reported quality of life (QOL) and satisfaction with the aforementioned factors.

Methods

Between the years 2000 and 2004, the authors treated 81 patients with medically refractory TN by using GKS. Fifty-two patients responded to a questionnaire regarding pain control, activities of daily living, QOL, and patient satisfaction.

The median follow-up duration was 16.5 months. Twenty-two patients (42.3%) had complete pain relief, 14 (26.9%) had partial but satisfactory pain relief, and in 16 patients (30.8%) the treatment failed. Seven patients (13.5%) reported a recurrence during the follow-up period, and 25 (48.1%) reported a significant (> 50%) decrease in their pain within the 1st month posttreatment. The mean decrease in the total dose of pain medication was 75%. Patients' self-reported QOL scores improved 90% and the overall patient satisfaction score was 80%.

Conclusions

The authors found that GKS is a minimally invasive and effective procedure that yields a favorable outcome for patients with recurrent or refractory TN. It may also be offered as a first-line surgical modality for any patients with TN who are unsuited or unwilling to undergo microvascular decompression.
Surgical anatomy of supratentorial midline lesions
Authors: Yaşargil M. Gazi , Türe Uğur , Yaşargil ¸ Dianne C. H.
Published: January 2008

Object

In this paper the authors correlate the surgical aspects of deep median and paramedian supratentorial lesions with the connective fiber systems of the white matter of the brain.

Methods

The cerebral hemispheres of 10 cadaveric brains were dissected in a mediolateral direction by using the fiber dissection technique, corresponding to the surgical approach.

Conclusions

This study illuminates the delicacy of the intertwined and stratified fiber laminae of the white matter, and establishes that these structures can be preserved at surgical exploration in patients.
The anterior sylvian point and the suprasylvian operculum
Authors: Ribas Guilherme Carvalhal , Ribas Eduardo Carvalhal , Rodrigues Consuelo Junqueira
Published: January 2008

Object

The sylvian fissure or lateral sulcus is the most identifiable feature of the superolateral brain surface and constitutes the main microneurosurgical corridor, given the high frequency of approachable intracranial lesions through this route. The anterior sylvian point (ASyP) divides this fissure in its main anterior and posterior rami and was evaluated in this study for its morphology, exact location, and sulcal and neural relationships to assess its suitability as an initial, visually identifiable landmark for further neuroimaging and intraoperative estimation of its adjoining suprasylvian structures.

Methods

This study is based on 32 formalin-fixed cerebral hemispheres. The brains were removed from the skulls of 16 cadavers after the introduction of plastic catheters through properly positioned burr holes; the number of specimens for some of the analyzed data differed because of incorrect positioning of catheters or damage to the studied structures caused by the initial steps of the study.

The ASyP had a cisternal aspect in 94% of the specimens and was always located inferior to the triangular part of the inferior frontal gyrus, 2.3 ± 0.5 cm in front of the inferior rolandic point. The ASyP was located underneath the 1.5-cm-diameter cranial area of the anterior aspect of the squamous suture. Its adjoining structures that compose the suprasylvian operculum have constant basic morphological configurations.

Conclusions

The ASyP underlies the anterior aspect of squamous suture just behind the pterion, can be easily recognized, and constitutes a reliable initial sulcal landmark for further estimation of the suprasylvian sulcal and gyral structures. The suprasylvian operculum can be understood as a series of convolutions roughly arranged as a V-shaped convolution, with its vertex constituted by the ASyP, followed by three U-shaped convolutions and one C-shaped convolution.
An anteromedial approach to the temporal horn to avoid injury to the optic radiation fibers and uncinate fasciculus: anatomical and technical note
Authors: Coppens Jeroen R. , Mahaney Kelly B. , Abdulrauf Saleem I.
Published: January 2008

Object

The aim of this study was to define an anteromedial approach to the temporal horn via a transsylvian approach to avoid injury to the optic radiation fibers as well as the uncinate fasciculus. This route was compared with standard surgical approaches to the temporal horn, and their relationship to the optic radiation and uncinate fasciculus was reviewed.

Methods

Three cadaveric brain specimens were prepared with freezing and thawing cycles according to the Klingler technique. Dissection was performed in a lateral-to-medial fashion with the help of wooden spatulas. Photographs were taken through the operating microscope at every level of the dissection. The dissection was continued until the optic radiation was encountered. Particular attention was paid to the relationship of the uncinate fasciculus with the optic radiation. An anteromedial transsylvian approach was defined to enter the temporal horn without injuring the optic radiation or the uncinate fasciculus.

Conclusions

A transsylvian anteromedial approach through the pyriform cortex at the level of the anterior and superior surface of the uncus enables a safe entry into the temporal horn without injury to the optic radiation fibers or the main part of the uncinate fasciculus.
Surgical outcomes and seizure control rates after resection of dysembryoplastic neuroepithelial tumors
Authors: Sandberg David I. , Ragheb John , Dunoyer Catalina , Bhatia Sanjiv , Olavarria Greg , Morrison Glenn
Published: January 2008

Object

In this study the authors review the outcomes in pediatric patients who presented with seizures and underwent resection of dysembryoplastic neuroepithelial tumors (DNETs). The authors focus on the diagnostic evaluation and surgical techniques that facilitate gross–total tumor resection and subsequent freedom from seizures.

Methods

Eighteen patients between the ages of 1 month and 13 years who presented with seizures underwent resection of DNETs between January 1992 and December 2004. Preoperative evaluation included magnetic resonance (MR) imaging and interictal scalp electroencephalography (EEG) in all patients, functional MR imaging in eight patients, video monitoring with ictal scalp EEG in 12 patients, interictal single-photon emission computerized tomography (SPECT) scanning in one patient, and ictal SPECT scanning in two patients. Thirteen patients underwent one-stage procedures, whereas five underwent two-stage procedures (implantation of monitoring electrodes followed by tumor resection), either for functional language mapping (three patients) or due to inconclusive preoperative data (two patients). Intraoperative electrocorticography (ECoG) was performed in 17 patients and led to resection of the cerebral cortex beyond the tumor margins in 10 of them. According to operative reports, gross–total tumor resections were achieved in all patients, but one child had minimal residual tumor on postoperative MR images that has remained stable. The only surgical complication was a transient third cranial nerve palsy. Over a median follow-up duration of 1.6 years, all patients are seizure free and without radiographically detected tumor recurrence.

Conclusions

Dysembryoplastic neuroepithelial tumors are a highly treatable cause of epilepsy in children. Excellent rates of complete tumor resection and seizure control with minimal morbidity can be attained using intraoperative ECoG and two-stage surgical procedures when appropriate.
Pilomyxoid astrocytoma: diagnosis, prognosis, and management
Authors: Komotar Ricardo J. , Mocco J , Jones Jess E. , Zacharia Brad E. , Tihan Tarik , Feldstein Neil A. , Anderson Richard C. E.
Published: January 2008

Pilomyxoid astrocytoma (PMA) is a recently defined pediatric brain tumor; PMAs were previously classified within the pilocytic astrocytoma (PA) category. Nevertheless, PMA has different histological features and has been shown to behave more aggressively than PA. These findings indicate that PMA may be a unique entity that is distinct from PA, or it may be an unusual variant. To increase awareness of PMA within the neurosurgical community, the authors review the diagnostic criteria, prognostic implications, and current management of this recently described pediatric low-grade astrocytoma.
Expanded endonasal approach: the rostrocaudal axis. Part II. Posterior clinoids to the foramen magnum
Authors: Kassam Amin , Snyderman Carl H. , Mintz Arlan , Gardner Paul , Carrau Ricardo L.
Published: January 2008

Object

Transsphenoidal approaches have been used for a century for the resection of pituitary and other sellar tumors. Recently, however, the standard endonasal approach has been expanded to provide access to other parasellar lesions. With the addition of the endoscope, this expansion has significant potential for the resection of skull base lesions.

Methods

The anatomical landmarks and surgical techniques used in expanded (extended) endoscopic approaches to the clivus and cervicomedullary junction are reviewed and presented, accompanied by case illustrations of each segment (or module) of approach.

The caudal portion of the midline anterior skull base and the cervicomedullary junction is divided into modules of approach: the middle third of the clivus, its lower third, and the cervicomedullary junction. Case illustrations of successful resections of lesions via each module of the approach are presented and discussed.

Conclusions

Endoscopic expanded endonasal approaches to caudally located midline anterior skull base and cervicomedullary lesions are feasible and hold great potential for decreased morbidity. The effectiveness and appropriate use of these techniques must be evaluated by close examination of outcomes as case series expand.
Postoperative cauda equina syndrome in patients undergoing single-level lumbar microdiscectomy
Authors: Dimopoulos Vassilios , Fountas Kostas N. , Machinis Theofilos G. , Feltes Carlos , Chung Induk , Johnston Kim , Robinson Joe Sam , Grigorian Arthur
Published: January 2008

Cauda equina syndrome is a well-documented complication of uneventful lumbar microdiscectomy. In the vast majority of cases, no radiological explanation can be obtained. In this paper, the authors report two cases of postoperative cauda equina syndrome in patients undergoing single-level de novo lumbar microdiscectomy in which intraoperative electrophysiological monitoring was used. In both patients, the amplitudes of cortical and subcortical intraoperative somatosensory evoked potentials (SSEPs) abruptly decreased during discectomy and foraminotomy. In the first patient, a slow, partial improvement of SSEPs was observed before the end of the operation, whereas no improvement was observed in the second patient. In the first case, clinical findings consistent with cauda equina syndrome were seen immediately postoperatively, whereas in the second one the symptoms developed within 1.5 hours after the procedure. Postoperative magnetic resonance images obtained in both patients, and a lumbar myelogram obtained in the second one revealed no signs of conus medullaris or nerve root compression. Both patients showed marked improvement after an intense course of rehabilitation. The authors' findings support the proposition that intraoperative SSEP monitoring may be useful in predicting the development of cauda equina syndrome in patients undergoing lumbar microdiscectomy. Nevertheless, further prospective clinical studies are necessary for validation of these findings.
Transcavernous approach to diseases of the anterior upper third of the posterior fossa
Authors: Krisht Ali F.
Published: January 2008

Object

The region in the upper anterior third of the posterior fossa is a surgically hidden, narrow corridor between the petroclival surface anteriorly and the surface of the brainstem posteriorly. Although several approaches have been described to help surgeons reach this region, few of them enable practitioners to reach the different corners of the area and provide as wide a view as the one achieved using the transcavernous route.

Methods

A transcavernous approach was used in 91 cases (50 complex upper basilar artery [BA] aneurysms, 30 upper petroclival junction meningiomas, five trigeminal nerve schwannomas, three upper clival chordomas, and three anterior pontine lesions) involving the anterior upper third of the posterior fossa. The approach uses the pretemporal route with exposure of the lateral wall of the cavernous sinus. It entails removal of the anterior clinoid process. The posterior clinoid process is also removed when necessary. The approach leads to the upper basilar region. It is widened inferiorly to expose the anterior aspect by removal of the posterior clinoid process and the petroclival osseous and dural elements. Its lateral extension exposes the region of the Meckel cave and it can be widened by removal of the petrous apex.

Seventy patients experienced new transient mild cranial neuropathies, 67 of whom recovered fully. Surgically related ischemic morbidities occurred in three patients with BA aneurysms (one small medial thalamic infarct, ataxia due to superior cerebellar artery ischemia, and distal middle cerebral artery embolus in a patient with atrial fibrillation in whom anticoagulation therapy was stopped). All the neuropathies in patients with BA aneurysms were oculomotor and recovery was the rule in all of them. Three new permanent cranial neuropathies occurred in the patients with meningiomas. In seven patients with preoperative neuropathy, two had partial improvement. Five patients with atypical meningiomas were treated with postoperative radiation therapy. Progression occurred later in four patients who were treated with gamma knife surgery. There were no surgery-related deaths. More than 1 year of follow-up data were available in 85 patients, and 94% of those patients were in an active and functional state (Glasgow Outcome Scale scores of 4 and 5).

Conclusions

The safety achieved with the transcavernous route allows surgeons to achieve wide exposures to lesions involving the anterior upper third of the posterior fossa. It is an approach that should be mastered by every neurosurgeon dealing with cranial lesions.
Technical strategies to approach aneurysms of the vertebral and posterior inferior cerebellar arteries
Authors: Krayenbühl Niklaus , Guerrero Carlos A. , Krisht Ali F.
Published: January 2008

Object

Aneurysms of the vertebral artery (VA) and proximal posterior inferior cerebellar artery (PICA) are rare and challenging lesions, as they are located in front of the brainstem and surrounded by the lower cranial nerves. Many different approaches have been described for their treatment, and have yielded different results. With the use of different examples of lesions, the authors describe their surgical strategy in the management of VA and PICA aneurysms.

Methods

The far-lateral approach was used, and the potential of its different extensions according to the specific anatomical location and configuration of different types of aneurysms is emphasized.

Conclusions

With the present knowledge of the microsurgical anatomy in the region of the foramen magnum, the far-lateral approach can be tailored to the specific anatomical and morphological configuration of an aneurysm in this region with good surgical results.