associated with DO. The seven nonsegmental cases of OPLL (two continuous and five mixed-type OPLL) were accompanied by one case of isolated, three of double-layer, and three of en bloc DO. There was no significant difference between segmental and nonsegmental OPLL and type of DO, or between type of OPLL associated with DO and type of DO (Fisher exact test). Relationship Between Neuroimaging Modalities and Ability to Identify OPLL and DO As shown in Table 1 , lateral plain radiography, thinslice sagittal polytomography, axial and sagittal reformation on CT scanning
Junichi Mizuno, Hiroshi Nakagawa, Naoki Matsuo, and Joonsuk Song
Sandra L. Poliachik, Andrew V. Poliakov, Laura A. Jansen, Sharon S. McDaniel, Carter D. Wray, John Kuratani, Russell P. Saneto, Jeffrey G. Ojemann, and Edward J. Novotny Jr
Imaging-guided surgery (IGS) systems are widely used in neurosurgical practice. During epilepsy surgery, the authors routinely use IGS landmarks to localize intracranial electrodes and/or specific brain regions. The authors have developed a technique to coregister these landmarks with pre- and postoperative scans and the Montreal Neurological Institute (MNI) standard space brain MRI to allow 1) localization and identification of tissue anatomy; and 2) identification of Brodmann areas (BAs) of the tissue resected during epilepsy surgery. Tracking tissue in this fashion allows for better correlation of patient outcome to clinical factors, functional neuroimaging findings, and pathological characteristics and molecular studies of resected tissue.
Tissue samples were collected in 21 patients. Coordinates from intraoperative tissue localization were downloaded from the IGS system and transformed into patient space, as defined by preoperative high-resolution T1-weighted MRI volume. Tissue landmarks in patient space were then transformed into MNI standard space for identification of the BAs of the tissue samples.
Anatomical locations of resected tissue were identified from the intraoperative resection landmarks. The BAs were identified for 17 of the 21 patients. The remaining patients had abnormal brain anatomy that could not be meaningfully coregistered with the MNI standard brain without causing extensive distortion.
This coregistration and landmark tracking technique allows localization of tissue that is resected from patients with epilepsy and identification of the BAs for each resected region. The ability to perform tissue localization allows investigators to relate preoperative, intraoperative, and postoperative functional and anatomical brain imaging to better understand patient outcomes, improve patient safety, and aid in research.
Susanna Bacigaluppi, Amir R. Dehdashti, Ronit Agid, Timo Krings, Michael Tymianski, and David J. Mikulis
The aim of this review was to evaluate the imaging tools used in diagnosis and perioperative assessment of moyamoya disease, with particular attention to the last decade.
Yukinari Kakizawa, Kazuhiro Hongo, Hisayoshi Takasawa, Yosuke Miyairi, Atsushi Sato, Yuichiro Tanaka, and Shigeaki Kobayashi
carefully to avoid injury to the strained oculomotor nerve. Results The real 3D CISS imaging method proved useful in 23 patients with aneurysms, hemifacial spasm, or small CPA tumors. In seven CPA tumors larger than 3 cm in diameter, the method failed to depict nerves and arteries well. When images were made in only one direction, especially in the axial view for CPA tumors, artifacts were introduced, which necessitated examination from an additional direction. Discussion In recent years, there has been a rapid development of diagnostic neuroimaging
Masahiko Tosaka, Masaru Tamura, Noboru Oriuchi, Mieko Horikoshi, Takashi Joshita, Kenichi Sugawara, Satoshi Kobayashi, Hideaki Kohga, Takatomo Yoshida, and Tomio Sasaki
radioisotope has not been described previously. Using the HMB-45 and S-100 protein antibodies, CSF immunocytochemical analysis is important for the diagnosis of leptomeningeal melanoma because of the simplicity, high specificity, and sensitivity of this test. Magnetic resonance imaging with gadolinium is indispensable to detect leptomeningeal enhancement accurately and to identify leptomeningeal melanoma, and 99m Tc-MIBI SPECT scanning is an additional and supplemental neuroimaging modality used to detect this disease. References 1. Aichner F
Ashish Goyal, Anil K. Singh, Daljit Singh, Vikas Gupta, Medha Tatke, Sanjiv Sinha, and Sushil Kumar
✓ The authors present an unusual case of intramedullary arachnoid cyst diagnosed in a patient after the lesion was resected. A wide decompressive surgery was performed and the lesion removed. Histopathological findings were consistent with the diagnosis of arachnoid cyst. Postoperatively the patient exhibited marked improvement in neurological status. To the best of the authors' knowledge, there is no case report of intramedullary arachnoid cyst reported in the literature. With the advent of newer neuroimaging modalities such as magnetic resonance imaging the number of cases of intramedullary arachnoid cysts encountered in the future may increase.
Vincent C. Traynelis
Symptomatic degenerative spinal disease is a serious medical condition that affects many individuals. Modern neuroimaging modalities, the development of new medications, and advances in operative and nonoperative treatments have all contributed to improved outcomes. Unfortunately, there remain a significant number of patients in whom primary therapy either fails or new or recurrent symptoms develop over time. The last decade has witnessed the invention of devices designed to reconstruct the spinal motion segment. These devices can be divided into those that primarily function to replace a nucleus pulposus and those that completely replace the disc complex. In this article the author reviews the background leading to the development of the current group of disc replacements. The design and preliminary clinical results obtained using major lumbar and cervical devices are also reviewed.
Case report and review of the literature
Kostas N. Fountas, Eftychia Z. Kapsalaki, and Joe Sam Robinson
✓ Pediatric spinal epidural hematoma is a very rare clinicopathological entity. In the vast majority of cases, spinal epidural hematomas have a nonspecific clinical presentation; this, along with their rapid progression, makes their early diagnosis and prompt surgical evacuation critical. Magnetic resonance imaging is the neuroimaging modality of choice, whereas hemilaminectomy or laminectomy is the indicated surgical intervention. The outcome is good when hematoma evacuation is performed before the onset of complete sensorimotor paralysis.
In this communication, the authors describe a 12-year-old girl with a traumatic acute cervical epidural hematoma. This lesion was successfully evacuated through a hemilaminectomy, and the patient had an excellent outcome. The pertinent literature is reviewed in terms of the incidence, origin, management, and prognosis of this rare and potentially disastrous clinical entity.
Nader Pouratian, Andrew F. Cannestra, Neil A. Martin, and Arthur W. Toga
Optical imaging of intrinsic signals (OIS) is a well-established neuroimaging modality by which functional cortical activity is mapped by detecting activity-related changes in cortical light reflectance. Light reflectance changes are detected by a charged-coupled device camera that captures images of the exposed cortex both at rest and during activity. Although to date OIS has only been used for research purposes, intraoperative OIS (iOIS) holds promise as a clinical mapping tool. In general, iOIS demonstrates good spatial correlation with electrocortical stimulation mapping (ECSM) and other electrophysiological modalities. Additionally, iOIS offers high spatial resolution (in microns), does not make contact with the surface of the brain, and introduces no potentially harmful compounds. Moreover, mapping is relatively rapid.
The authors review the potential contribution of iOIS to the intraoperative environment. Specifically, they review iOIS methodology, discuss signal origin, compare OIS with other functional mapping modalities, and explain its potential benefits and limitations. They propose that iOIS may, in the future, be used in conjunction with ECSM to improve the resolution and accuracy of intraoperative mapping, decrease total time of intraoperative mapping, and possibly improve neurological outcomes. Additional studies will be required to quantify the sensitivity and specificity of optical maps relative to ECSM before it can be implemented clinically.
Yuri P. Zozulya, Eugene I. Slin'ko, and Iyad I. Al-Qashqish
Spinal vascular malformations represent rare and insufficiently studied pathological entities characterized by considerable variation. Insufficient study of this disease is connected with the complexity of its diagnosis, which restricts the development of surgical treatments that are differentiated according to the type of malformation. Great difficulties are caused by the lack of a clear structural–hemodynamic classification of spinal arteriovenous malformations (AVMs). At present the classification created between 1991 and 1998 by the combined efforts of different authors is the most widely used one. According to this classification, four categories are distinguishable: Type I, dural arteriovenous fistulas (AVFs); Type II, intramedullary glomus AVMs; Type III, juvenile or combined AVMs; and Type IV, intradural perimedullary AVFs. Vascular tumors are also classified, as follows: hemangiomas, hemangioblastomas, angiosarcomas, hemangiopericytomas, angiofibromas, angiolipomas, and hemangioendotheliomas, as well as cavernous malformations.
In this study the authors analyze the diagnostic data and results of treatment in 91 patients with AVMs and AVFs who were treated at the Institute of Neurosurgery between 1995 and 2005. The patients' ages ranged from 9 to 83 years; the mean age was 42.9 years. For spinal vascular malformations we devised a classification that took into account the aforementioned features of AVMs: the anatomical characteristics of a malformation and its angiostructural and hemodynamic features. In all patients the neuroimaging modalities used in the investigation of their lesions included magnetic resonance (MR) imaging and selective spinal angiography. Three-dimensional computerized tomography angiography studies were obtained in 14 patients, and MR angiography was used in 17.
For successful surgical treatment of spinal AVMs it is necessary to obtain data about their localization, vascular structure, and hemodynamics that are as complete as possible. This information will promote the use of optimum surgical procedures and the latest methods of microsurgical and endovascular interventions, with treatments differentiated according to the type of malformation. One should try to use the least invasive endovascular approach in these cases,where possible, to occlude the AVM or reduce the intensity of blood flow by means of embolization. To perform an AVM resection or occlusion, one should use a direct approach to the malformation, blocking only the vessels supplying blood to the malformation and preserving the vessels feeding the spinal cord.