PubMed Central (PMC3 - NLM DTD)
(2,081,148 recursos)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
Mostrando recursos 281 - 300 de 551
281.
Endovascular Treatment of Transverse-Sigmoid Sinus Dural Arteriovenous Malformations Presenting as Pulsatile Tinnitus - Shownkeen, Harish; Yoo, Kevin; Leonetti, John; Origitano, T.C.
Transverse-sigmoid sinus dural arteriovenous malformations (DAVM) are uncommon vascular lesions for which complete cure may be difficult to obtain. A wide variety of treatments for these lesions include observation, arterial compression, surgical resection, and endovascular embolization. We propose that transverse-sigmoid sinus DAVM can be completely cured by occluding the ipsilateral dural sinus with detachable balloon and Guglielmi detachable coils (GDC) coils before arterial feeder embolization with histoacryl. Three patients who presented with pulsatile tinnitus and normal magnetic resonance imaging (MRI) studies underwent angiography, which demonstrated transverse-sigmoid sinus DAVM. All three patients wer treated with retrograde transvenous sinus embolization with complete...
284.
Comparison of Scientific Calipers and Computer-Enabled CT Review for the Measurement of Skull Base and Craniomaxillofacial Dimensions - Citardi, Martin J.; Herrmann, Brian; Hollenbeak, Chris S.; Stack, Brendan C.; Cooper, Margaret; Bucholz, Richard D.
Traditionally, cadaveric studies and plain-film cephalometrics provided information about craniomaxillofacial proportions and measurements; however, advances in computer technology now permit software-based review of computed tomography (CT)-based models. Distances between standardized anatomic points were measured on five dried human skulls with standard scientific calipers (Geneva Gauge, Albany, NY) and through computer workstation (StealthStation 2.6.4, Medtronic Surgical Navigation Technology, Louisville, CO) review of corresponding CT scans. Differences in measurements between the caliper and CT model were not statistically significant for each parameter. Measurements obtained by computer workstation CT review of the cranial skull base are an accurate representation of actual bony anatomy....
285.
Papillary Tumor of the Temporal Bone - Schick, Bernhard; Kronsbein, Hartmut; Kahle, Gabriele; Prescher, Andreas; Draf, Wolfgang
Papillary tumors of the middle and inner ear have been interpreted histogenetically in many ways. In 1989 Heffner proposed the endolymphatic sac epithelium as a possible origin. These rare tumors are clinically aggressive and can cause extensive temporal bone destruction. Because of this behavior, endolymphatic sac tumors (ELST) were classified as low-grade adenocarcinomas, although metastasis has not yet been documented. Two papillary neoplasms of the temporal bone are presented, which we believe are examples of adenomatous tumors arising from the epithelium of the endolymphatic sac. One was associated with a pituitary adenoma. A third case of a papillary middle ear...
287.
Exposure of the Petrous Segment of the Internal Carotid Artery Through the Extradural Subtemporal Middle Cranial Fossa Approach: A Systematic Anatomical Study - Mortini, Pietro; Mandelli, Carlo; Gerevini, Simonetta; Giovanelli, Massimo
The relationships between the horizontal segment of the internal carotid artery (ICA) and other petrous apex structures was studied in 14 anatomical specimens obtained from routine autopsies and on 10 magnetic resonance images obtained from healthy volunteers. The dissection was performed under an operating microscope using the middle fossa transpetrous approach. A pentagonshaped area of 67.91 mm2 posterior to the trigeminal nerve and bordered by anatomical structures was identified inside the petrous apex. The results suggest a method for exposing the ICA when the artery is not visible after dural elevation.
288.
The Architecture of the Arcuate EminenceA Microanatomical Study and Its Application to the Transpetrosal Approach - Katsuta, Toshiro; Matsushima, Toshio; Fukui, Masashi; Rhoton, Albert L.
This study was performed to determine if the arcuate eminence can be drilled down without opening the semicircular canal to obtain a flatter operative field during an anterior or posterior transpetrosal approach. The depth of the superior semicircular canal from the top of the arcuate eminence was measured in 43 dry temporal bones. We found that the arcuate eminence was situated approximately 20 mm from the petrosigmoid intersection, and the superior semicircular canal was located 2.0 mm deep from the top of the arcuate eminence (range, 0.2 mm to 4.2 mm). The arcuate eminence consists of either (1) the otic...
290.
The Effects of Clonidine Premedication and Scalp Infiltration of Lidocaine on Hemodynamic Responses to Laryngoscopy and Skull Pin Head-Holder Insertion During Skull Base Procedures - Jellish, W. Scott; Theard, M. Angele; Cheng, Mary Ann; Leonetti, John P.; Crowder, C. Michael; Tempelhoff, Rene
This study was designed to determine if oral clonidine or lidocaine, injected into the scalp before head-holder (H-H) insertion, would attenuate the hemodynamic effects associated with intubation and H-H placement. Thirty-four patients undergoing skull base procedures were randomized to four groups. Group 1 received clonidine 5 mcg/kg po before surgery with 10 to 15 ml of 1% lidocaine infiltrated at pin insertion sites; Group 2 received clonidine with saline infiltration; Group 3 received a placebo preoperatively and had lidocaine infiltrated at pin sites; and Group 4 received a placebo with saline infiltrated. All patients had a standard anesthetic titrated to...
291.
A Cranio-Orbital-Zygomatic Approach to Dumbbell-Shaped Trigeminal Neurinomas Using the Petrous Window - Chung, Young Seob; Gwak, Ho-Shin; Jung, Hee-Won; Paek, Sun-Ha; Kim, Dong Gyu; Choi, Kil-Soo
We applied a cranio-orbital-zygomatic approach that extends the temporal craniotomy more posteriorly and minimizes the frontal orbitotomy of an ordinary orbitozygomatic approach in order to provide wide access to the already eroded petrous apices along the long axis of trigeminal neurinomas. We treated seven dumbbell-shaped trigeminal neurinomas between 1991 and 1998 (mean follow-up, 38 months; range, 9 to 109 months). The configuration of the tumor mass was assessed on magnetic resonance imaging by measuring its long diameter in the middle and posterior fossae and the width of petrous erosion. Tumors were then classified into five types based on their distribution...
293.
Posterior Fossa Ependymoma - Grady, M. Sean; Judy, Kevin D.; Bigelow, Douglas C.; Sinson, Grant P.; Rostomily, Robert; Winn, H. Richard
294.
Carotid-Cavernous Fistulas: Pathogenesis and Routes of Approach to Endovascular Treatment - Shownkeen, Harish; Bova, Davide; Origitano, Thomas C.; Petruzzelli, Guy J.; Leonetti, John P.
The etiology, classification, clinical presentation, complications, and intravascular routes to image and treat carotid-cavernous fistulas percutaneously are described. Endoarterial and transvenous approaches (through the jugular, inferior petrosal, or cavernous veins) are discussed in relation to the etiology, size, and characteristics of the fistulas, as well as in relation to the planned therapeutic approach and its possible complications. Possible outcomes, with particular attention to the internal carotid circulation, side effects, and complications also are discussed in relation to etiology and type of fistula. Four exemplary cases are presented.
296.
Fully Endoscopic Vascular Decompression of the Facial Nerve for Hemifacial Spasm - Eby, Joseph B.; Cha, Sung Tae; Shahinian, Hrayr K.
Hemifacial spasm is an uncommon disorder manifesting as a unilateral, involuntary, sporadic contraction of the musculature innervated by the seventh cranial nerve. Although debated, the etiology of hemifacial spasm is generally accepted as compression of the facial nerve by vessels of the posterior circulation. Early surgical techniques were ineffective and fraught with morbidity. Over the past 25 years microvascular decompression surgery has allowed the safe and effective treatment of hemifacial spasm. Recent reports combining microsurgical and endoscopic techniques have documented the advantages of the endoscope in exposing the anatomy of this region. Enhanced visualization allows a less traumatic dissection and...
297.
Staged Resection of Large Hypervascular Vestibular Schwannomas in Young Adults - Abe, Takumi; Izumiyama, Hitoshi; Imaizumi, Youichi; Kobayashi, Shinsuke; Shimazu, Motohiko; Sasaki, Ken; Matsumoto, Kiyoshi; Kushima, Miki
Two young adults underwent resection of large hypervascular vestibular schwannomas (acoustic neuromas) via two-stage surgery. The first patient, a 27-year-old woman with hydrocephalus, had a large hypervascular vestibular tumor in the left cerebellopontine angle (CPA) supplied by the left anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA). The second patient, a 34-year-old woman, had a large AICA-supplied hypervascular vestibular tumor in the left CPA that displaced the brain stem significantly. At the initial stage, only the lateral aspect of the tumor was debulked due to excessive bleeding from the tumor bed. Angiography 1 or 2 months after...
298.
Meningiomas Intrinsic to the Geniculate Ganglion - Falcioni, Maurizio; Piccirillo, Enrico; Taibah, Abdelkader; Sanna, Mario
Geniculate ganglion meningiomas are extremely rare lesionsonly 14 cases have been reported in the literature. Two new cases of these tumors are described. On computed tomography and magnetic resonance imaging, both lesions appeared centered on the area of the geniculate ganglion, extending to the tympanic cleft and eroding the middle cranial fossa floor. The first case was treated through a middle cranial fossa approach. Because the tumor was so large in the second case, a subtotal petrosectomy was used. The authors review the literature to clarify the clinical and radiological characteristics of these tumors and their surgical treatment.
299.
Anteromedial Approach to the Orbit - Deda, Haluk; Ugur, Hasan Çaglar; Yorulmaz, Irfan; Kucuk, Babur
This study evaluated the surgical results of the anteromedial approach for treatment of orbital lesions in 16 patients. Pre- and postoperatively, all patients underwent a complete physical examination focusing on the head and neck area including a thorough ophthalmologic evaluation, computerized tomography, and magnetic resonance imaging. The surgical approach was limited to a medial orbitotomy in five patients; the remaining 11 patients underwent a medial orbitotomy combined with an external sphenoethmoidectomy. The tumor was removed completely without damaging the intraorbital neurovascular structures in all but one patient whose recurrent clival chordoma extended beyond the limits of an extracranial approach. Fibro-osseous...
281.
