Anatomy of the mastoid emissary vein and venous system of the posterior neck region: neurosurgical implications.

Objective: The superficial venous system of the posterior neck (suboccipital venous plexus) is a potential source of complications from bleeding and air embolism. Because there is little information available about this in the literature, an anatomic study of the superficial posterior neck venous system and a morphometric analysis of the mastoid emissary vein (MEV) complex were undertaken. Both surgical and endovascular implications were considered.

Surgical treatment of high-risk intracranial dural arteriovenous fistulae: clinical outcomes and avoidance of complications.

Objective: An increasing number of intracranial dural arteriovenous fistulae (DAVFs) are amenable to endovascular treatment. However, a subset of patients with high-risk lesions requires surgical intervention for complete obliteration. We reviewed our experience with the surgical management of high-risk intracranial DAVFs and offer recommendations to minimize complications based on fistula location and type.

Neuroscience of meditation.

Dhyana-Yoga is a Sanskrit word for the ancient discipline of meditation, as a means to Samadhi or enlightenment. Samadhi is a self-absorptive, adaptive state with realization of one's being in harmony with reality. It is unitive, undifferentiated, reality-consciousness, an essential being, which can only be experienced by spontaneous intuition and self-understanding.

Giant, partially thrombosed aneurysm develops after remote angiographically negative subarachnoid hemorrhage: case report.

Objective: This is the first report of the rupture of a giant aneurysm in a patient who sustained a remote angiographically negative subarachnoid hemorrhage (SAH).

Clinical Presentation: A 62-year old woman initially presented with a Fisher Grade III SAH 9 years ago. Her evaluation, which included cerebral angiography, magnetic resonance imaging scans, and magnetic resonance angiography of the head and neck, failed to reveal the cause of the hemorrhage.

Application of a novel headrest system for odontoid screw fixation. Technical note.

The authors describe a unique headholder device adapted to facilitate the placement of anterior odontoid screws. The patient's head is affixed in the headholder equipped with an articulating arm that can be placed in a paramedian fashion. This configuration rigidly fixates the head and provides an unencumbered open-mouth view of the odontoid using radiographic images, thus making screw placement easier.

Synchronous endoscopy and microsurgery: a novel strategy to approach complex ventricular lesions. Report of three cases.

Simultaneous endoscopic and microsurgical (synchronous) approaches represent a new paradigm in the treatment of complex ventricular lesions. This technique is well suited for lesions that involve multiple ventricular or cisternal compartments, have a nonlinear axis, or adhere to critical anatomical or neurovascular structures. Two distinct operative corridors, one endoscopic and the other microsurgical, are used during synchronous approaches to address such lesions, increasing the likelihood of a safe and complete resection.

Bilateral ethmoidal dural arteriovenous fistulae: a previously unreported entity: case report.

Objective And Importance: Ethmoidal dural arteriovenous fistulas (AVFs) are rare intracranial lesions associated with a high risk of intracranial hemorrhage. Reported hemorrhage rates have ranged from 62 to 91%, and an aggressive clinical course is more likely than a benign clinical course. We describe the first case of a patient with bilateral ethmoidal dural AVFs.

An anatomical evaluation of the mini-supraorbital approach and comparison with standard craniotomies.

Objective: To compare anatomically the surgical exposure provided by pterional (PT), orbitozygomatic (OZ), and minisupraorbital (SO) craniotomies.

Methods: Seven sides of six fixed cadaver heads injected with silicone were used. The mini-SO craniotomy followed by the PT and OZ approaches were performed sequentially.

Estimating the parameters of a model for protein-protein interaction graphs.

We find accurate approximations for the expected number of three-cycles and unchorded four-cycles under a stochastic distribution for graphs that has been proposed for modelling yeast two-hybrid protein-protein interaction networks. We show that unchorded four-cycles are characteristic motifs under this model and that the count of unchorded four-cycles in the graph is a reliable statistic on which to base parameter estimation. Finally, we test our model against a range of experimental data, obtain parameter estimates from these data and investigate possible improvements in the model.

Durectomy and reconstruction for the treatment of a recurrent spinal meningioma. Case report.

The management of spinal meningiomas with extensive involvement of the dura mater is controversial. The principal difficulty in performing a resection is the potential for complications associated with this approach. The authors present the case of a pregnant 35-year-old woman in whom bilateral lower-extremity numbness, weakness, gait ataxia, and myelopathy developed.

Endovascular reconstruction with the Neuroform stent as monotherapy for the treatment of uncoilable intradural pseudoaneurysms.

Objective: Intradural pseudoaneurysms have a malignant natural history and can be difficult to treat if parent vessel deconstruction is not feasible. These lesions often involve a long arterial segment and lack a defined saccular component that would safely accommodate the introduction of embolization coils. The current report describes the successful endovascular treatment of these lesions using a strategy of Neuroform stent reconstruction.

Anxiety, panic and adult asthma: a cognitive-behavioral perspective.

A review of previous research suggests increased probability of the prevalence of anxiety disorders, and particularly panic disorder and panic attacks in patients with asthma, as compared to a normal population. Research also indicates significant levels of co-morbidity between asthma and anxiety as measured on dimensional scales of anxiety and panic. Clinical anxiety and panic manifestations affect symptom perception and asthma management through the effects of anxiety symptoms such as hyperventilation, and indirectly through self-management behavior and physician response.

Treatment of recurrent previously coiled anterior circulation aneurysm with minimally invasive keyhole craniotomy: report of two cases.

The use of minimally invasive techniques has not yet been reported for the treatment of recurrent aneurysms after coil embolization. A 47-year-old man with a long history of headaches had an anterior communicating aneurysm that had previously been coil embolized. Three-year follow-up angiography showed a significant recurrence.

Quantification and comparison of telovelar and transvermian approaches to the fourth ventricle.

Objective: To quantify the exposure to the fourth ventricle obtained with the telovelar and transvermian approaches.

Methods: The telovelar, with and without C1 posterior arch removal, and transvermian approaches were performed on six cadaveric heads. The area of surgical exposure was calculated from triangles formed by defined anatomic points.

Surgical management of distal coil migration and arterial perforation after attempted coil embolization of a ruptured ophthalmic artery aneurysm: technical case report.

Objective And Importance: Distal coil migration is a rare but hazardous complication of aneurysm coil embolization. Various microsnare devices have been developed to address this problem. We describe the surgical management of a case in which microsnare retrieval failed.

Retino-hypothalamic-pineal hypothesis in the pathophysiology of primary headaches.

Primary headaches include migraine, tension, cluster headaches, paroxysmal hemicrania and miscellaneous headaches unassociated with structural lesions. A putative role of the retino-hypothalamic-pineal (RHP) axis in the pathophysiology of primary headaches is reviewed in terms of (1) retinal dysfunction, (2) hypothalamic dysfunction and human circadian desynchrony, (3) pineal melatonin dysfunction and (4) rostral limbic dysfunction mediating the human stress response. Unified RHP hypothesis is proposed, suggesting that an acute, periodic or chronic, circadian desynchrony and dysfunction of the whole or part of the RHP axis is implicated in the pathophysiology of primary headaches.

Long-term clinical and angiographic follow-up of unclippable wrapped intracranial aneurysms.

Objective: This is the largest contemporary series examining long-term clinical and angiographic follow-up of unclippable wrapped intracranial aneurysms.

Methods: The presentation, location and shape of aneurysm, wrapping technique, outcome at discharge and last follow-up, and change in aneurysm at last angiographic follow-up were reviewed retrospectively in 74 patients with wrapped or clip-wrapped aneurysms. Patients in whom wrapping was used in conjunction with primary clipping were excluded.

Resolution of hemifacial spasm after surgical obliteration of a tentorial arteriovenous fistula: case report.

Objective And Importance: We describe a patient with a tentorial dural arteriovenous fistula who presented with ipsilateral hemifacial spasm.

Clinical Presentation: A 50-year-old man sought treatment for left facial twitching that worsened over 6 months. Magnetic resonance imaging and catheter angiography demonstrated a left tentorial dural arteriovenous fistula.

Combined skull base approaches to the posterior fossa. Technical note.

Combined approaches to the skull base provide maximal exposure of the complex and eloquent anatomical structures contained within the posterior fossa. Common to these combined exposures are variable degrees of petrous bone removal. Understanding the advantages of each approach is critical when attempting to balance increases in operative exposure against the risk of potential complications.

Antiplatelet therapy in neuroendovascular therapeutics.

Our understanding of the pharmacology of antiplatelet therapy continues to evolve rapidly. Although the existing data are primarily generated in the setting of interventional and preventative cardiology studies, these data may be extrapolated to guide the rational application of these agents in neuroendovascular procedures. Platelet function testing represents an increasingly available and practical method by which to verify the adequacy of therapy and guide clinical decision making.

Monorail snare technique for the recovery of stretched platinum coils: technical case report.

Objective And Importance: Coil stretching represents a potentially hazardous technical complication not infrequently encountered during the embolization of cerebral aneurysms. Often, the stretched coil cannot be advanced into the aneurysm or withdrawn intact. The operator is then forced to attempt to retract the damaged coil, which may result in coil breakage, leaving behind a significant length of potentially thrombogenic stretched coil material within the parent vessel.

Usefulness of the Neuroform stent for the treatment of cerebral aneurysms: results at initial (3-6-mo) follow-up.

Objective: The Neuroform microstent, a flexible, self-expanding, nitinol stent specifically designed for use in the cerebral vasculature, became available in North America for aneurysm treatment in November 2002. The present report details our experience with the Neuroform stent over the past 2 years, with an emphasis on evolving treatment strategies and treatment durability at initial (3-6 mo) follow-up.

Methods: All patients included in this report were registered in a prospectively maintained database.

Biomechanical analysis of a resorbable anterior cervical graft containment plate.

Study Design: A series of in vitro experiments were performed in human cadaveric cervical spines in the normal condition, after discectomy and graft, and instrumented with MacroPore resorbable anterior plates (MacroPore, San Diego, CA). Flexibility, graft containment, and load-to-failure were studied.

Objective: To assess the stability, strength, and resistance to graft extrusion provided by the resorbable plate after discectomy and grafting.

Use of "bonnet" bypass with radial artery interposition graft in a patient with recurrent cranial base carcinoma: technical report of two cases and review of the literature.

Objective And Importance: Two patients with recurrent cranial base carcinomas involving the carotid artery received a "bonnet" bypass using the contralateral superficial temporal artery as the donor vessel because the ipsilateral common and external carotid arteries were unavailable. The radial artery was used as the graft.

Clinical Presentation: A 58-year-old man with ear pain and an enlarging mass involving the left cranial base and neck had undergone a right partial glossectomy and modified neck dissection followed by radiotherapy for squamous cell carcinoma.