2,007 research outputs found
Cranial Nerve I
This unit presents the basic protocol for imaging cranial nerve I. The olfactory bulbs and tracts mediate the sense of smell from the nasal cavity to the brain. Unfortunately they are located in a precarious position for MR imaging, above the airâfilled nasal cavity and ethmoid sinuses at a boneâairâsoft tissue interface. This creates problems with susceptibility artifact. This issue, plus the very small size of the structures to be studied and the superimposed eye motion artifact makes imaging of the olfactory system a technical challenge.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145299/1/cpmia0701.pd
Cranial Nerves III to VI
Cranial nerves III, IV, V, and VI are small structures that travel in a reproducible manner from the midbrain and pons to the cavernous sinus and then to the orbit. While there are branches that course through other foramina of the skull, the emphasis in MRI is to evaluate the brainstem, the cavernous sinus, and the pericavernous regions for pathology. This unit present a basic protocol for imaging cranial nerves III to VI. Because the nerves run from a posterior to an anterior position, coronal scanning is ideal for visualizing the nerves in crossâsection. Thin sections and contrast enhancement are required to best visualize the diseases that affect these nerves. An alternate protocol is also discussed for the case when demyelinating etiologies for the cranial nerve deficits are considered.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145278/1/cpmia0702.pd
A CPH-Like Picture in Two Patients with an Orbitocavernous Sinus Syndrome
Two patients with retroorbital pain syndromes with or without paresis of cranial nerves developed weeks after ipsilateral headache resembling chronic paroxysmal hemicrania (CPH) but without autonomic features. These findings might support the hypothesis that CPH may be caused by a pathological process in the region of the cavernous sinus, as has been proposed for the Tolosa-Hunt syndrome (THS)
A prospective randomized trial of fk506 versus cyclosporine after human pulmonary transplantation
We have conducted a unique prospective randomized study to compare the effect of PK506 and cyclosporine (CsA) as the principal immunosuppressive agents after pulmonary transplantation. Between October 1991 and March 1993, 74 lung transplants (35 single lung transplants [SLT], 39 bilateral lung transplant [BLT]) were performed on 74 recipients who were randomly assigned to receive either FK or CsA. Thirty-eight recipients (19 SLT, 19 BLT) received FK and 36 recipients (16 SLT, 20 BLT) received CsA. Recipients receiving FK or CsA were similar in age, gender, preoperative New York Heart Association functional class, and underlying disease. Acute rejection (ACR) was assessed by clinical, radiographic, and histologic criteria. ACR was treated with methylprednisolone, 1 g i.v./day, for three days or rabbit antithymocyte globulin if steroid-resistant.During the first 30 days after transplant, one patient in the FK group died of cerebral edema, while two recipients treated with CsA died of bacterial pneumonia (1) and cardiac arrest (1) (P=NS). Although one-year survival was similar between the groups, the number of recipients free from ACR in the FK group was significantly higher as compared with the CsA group (P<0.05). Bacterial and viral pneumonias were the major causes of late graft failure in both groups. The mean number of episodes of ACR/ 100 patient days was significantly fewer in the FK group (1.2) as compared with the CsA group (2.0) (P<0.05). While only one recipient (1/36=3%) in the group treated with CsA remained free from ACR within 120 days of transplantation, 13% (5/38) of the group treated with FK remained free from ACR during this interval (P<0.05). The prevalence of bacterial infection in the CsA group was 1.5 episodes/100 patient days and 0.6 episodes/100 patient days in the FK group. The prevalence of cytomegaloviral and fungal infection was similar in both groups.Although the presence of bacterial, fungal, and viral infections was similar in the two groups, ACR occurred less frequently in the FK-treated group as compared with the CsA-treated group in the early postoperative period (<90 days). Early graft survival at 30 days was similar in the two groups, but intermediate graft survival at 6 months was better in the FK group as compared with the CsA group. © 1994 by Williams and Wilkins
Radiologic-pathologic autopsy correlation of an internal watershed infarct, a case report
Internal watershed infarcts (IWIs) occur at the junction of the deep and superficial perforating arterial branches of the cerebrum. Despite documentation in the radiology literature, IWIs are rarely encountered at the time of autopsy. Here, we report the case of a 59-year-old incarcerated male who was brought to the emergency department after being found unresponsive on the floor of his jail cell. Initial examination and imaging demonstrated right-sided hemiplegia, aphasia, right facial droop, and severe stenosis of the left middle cerebral artery, respectively. Repeat imaging 4 days after admission and 26 days before death demonstrated advanced stenosis of the intracranial, communicating segment of the right internal carotid artery, a large acute infarct in the right posterior cerebral artery territory, and bilateral deep white matter ischemic changes with a right-sided ârosary-likeâ pattern of injury that is typical of IWIs. Postmortem gross examination showed that the right deep white matter lesion had progressed to a confluent, âcigar-shapedâ subacute IWI involving the right corona radiata. This is the first well-documented case of an IWI with radiologic imaging and photographic gross pathology correlation. This case uniquely highlights a rarely encountered lesion at the time of autopsy and provides an excellent visual representation of internal watershed neuroanatomy
Attitudes about Medical Malpractice: An American Society of Neuroradiology Survey
ABSTRACT SUMMARY: The concern over medicolegal liability is pervasive among physicians. We sought, through an email survey to the members of the ASNR, to assess the experience with and attitudes about the medicolegal environment among neuroradiologists. Of 4357 physicians surveyed, 904 answered at least 1 of the questions in the survey; 449 of 904 (49.7%) had been sued: 180 (44.9%) had been sued once, 114 (28.4%) twice, 60 (15.0%) 3 times, and 47 (11.7%) more than 3 times. The payouts for suits were most commonly in the 150,000 range, except for interventional neuroradiologists, in whom the most common value was 1,200,000. Only 9 of 481 (1.9%) of suits returned a plaintiff verdict. Despite reported outcomes that favored physicians with respect to cases being dropped (270/481 Ï 56.1%), settled without a payment (11/481 Ï 2.3%), or a defense verdict (46/481 Ï 9.6), most respondents (81.1%, 647/798) believed that the medicolegal system was weighted toward plaintiffs. More than half of the neuroradiologists (55.2%, 435/787) reported being mildly to moderately concerned, and 19.1% (150/787) were very or extremely concerned about being sued. ABBREVIATIONS: ASN
Fluorescence Bronchoscopic Surveillance in Patients With a History of Non-Small Cell Lung Cancer
Background Second lung primaries occur at a rate of 2% per patient per year after curative resection for non-small cell lung carcinoma (NSCLC). The aim of this study was to
evaluate the role of fluorescence bronchoscopy using the XillixÂź LIFE-Lung Fluorescent
Endoscopy SystemTM (LIFE-Lung system) in the surveillance of patients for second
NSCLC primaries after resection or curative photodynamic therapy (PDT)
MULTILEVEL FUNCTIONAL PRINCIPAL COMPONENT ANALYSIS FOR HIGH-DIMENSIONAL DATA
We propose fast and scalable statistical methods for the analysis of hundreds or thousands of high dimensional vectors observed at multiple visits. The proposed inferential methods avoid the difficult task of loading the entire data set at once in the computer memory and use sequential access to data. This allows deployment of our methodology on low-resource computers where computations can be done in minutes on extremely large data sets. Our methods are motivated by and applied to a study where hundreds of subjects were scanned using Magnetic Resonance Imaging (MRI) at two visits roughly five years apart. The original data possesses over ten billion easurements. The approach can be applied to any type of study where data can be unfolded into a long vector including densely bserved functions and images
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