Biomedical subjects

Edward J Escott

Publications and source records attributed to Edward J Escott.

7 recordsLinked to original sources

PubMed2006

Superior semicircular canal dehiscence: oblique reformatted CT images for diagnosis.

PURPOSE: To retrospectively determine, by using thin-section multi-detector row computed tomography (CT), whether additional reformations in the planes of Stenver and Pöschl change the diagnostic interpretation for superior semicircular canal dehiscence (SSCD) when compared with the diagnostic interpretation of standard coronal reformations for SSCD. MATERIALS AND METHODS: Institutional review board approval was obtained, patient anonymity was maintained, and the study was HIPAA compliant. Twenty-seven patients (17 men, 10 women; average age, 45 years; range, 19-72 years) suspected of having SSCD who underwent temporal bone multi-detector row CT were retrospectively identified from electronic medical records. An additional 27 control subjects (nine men, 18 women; average age, 50 years; range, 18-87 years), who underwent temporal bone multi-detector row CT for other reasons, were retrospectively selected from the same period. Two neuroradiologists with certificates of added qualification, one with 5 years and one with 9 years of experience interpreting temporal bone CT images, independently reviewed the 108 temporal bones twice. One review was restricted to transverse images and coronal reformations. The other review used transverse images, coronal reformations, and oblique reformations in the planes of Stenver and Pöschl. The observers were blinded to clinical history, and the two reviews took place 3 months apart to avoid recall bias. The primary outcome measure was the intraobserver discordance rate between the two reviews. kappa Statistics were used to evaluate both intraobserver and interobserver variability. RESULTS: Observer 1 diagnosed SSCD in 25 of 108 (23%) temporal bones and had no discordances between the two reviews. Observer 2 diagnosed SSCD in 21 of 108 (19%) temporal bones and had one intraobserver discordance. After a post hoc consensus review of this one discordance, the radiologic diagnosis remained equivocal. The discordance involved the right temporal bone of a patient suspected of having SSCD in the left temporal bone, so no clinical follow-up was available. CONCLUSION: Coronal reformations from multi-detector row CT of the temporal bone are sufficient for the evaluation of SSCD. Additional reformations in the planes of Stenver and Pöschl do not change the radiologic diagnosis and may be reserved for equivocal or confusing cases.

Adolescent↗

PubMed2006

Normal CT appearance of the distal thoracic duct.

OBJECTIVE: The aims of this study were to determine how often the distal thoracic duct can be identified on neck CT and to characterize the CT appearance of the duct. MATERIALS AND METHODS: In a review of electronic medical records from January 2001 to January 2003 we identified the cases of 500 patients who had undergone CT of the neck. Because they had confounding factors such as cancer or cervical lymphadenopathy, 199 of these patients were excluded, leaving 301 patients in the study: 131 (44%) male patients and 170 (56%) female patients. The age range was 11-92 years (average age, 46 years). Two head and neck radiologists used strict diagnostic criteria and consensus to identify the distal thoracic duct on both sides of the neck. One half of the images selected at random were flipped left to right. The purpose of randomization was to avoid interpretation bias, because the thoracic duct is known to typically course within the left side of the neck. The configuration of the distal duct was tabulated, and effects of age and sex were statistically evaluated. RESULTS: The left side of the neck was unevaluable in 26 (9%) of 301 patients because of streak artifact. In the other 275 patients, the distal thoracic duct was identified in the left side of the necks of 150 (55%) of the patients. Eleven of these patients (4%) also had a visible duct in the right side of the neck, but a right-sided duct was never identified without a left-sided counterpart. The distal thoracic duct had a tubular configuration in 70 (43%), a flared configuration in 72 (45%), and a long segmental fusiform dilation in 19 (12%) of 161 patients. Patient sex had no significant effect on the appearance of the distal thoracic duct. Older patient age had a slight positive effect on the size of the duct. CONCLUSION: Familiarity with the normal CT appearance of the distal thoracic duct can be helpful in differentiating a normal duct from pathologic lesions of the lower neck, such as lymphadenopathy.

Adolescent↗

PubMed2004

Naturally acquired West Nile virus encephalomyelitis in transplant recipients: clinical, laboratory, diagnostic, and neuropathological features.

BACKGROUND: In the 2003 West Nile virus (WNV) epidemic, Colorado reported more WNV cases than any other state, including an unprecedented number in organ transplant recipients. METHODS: Physicians caring for transplant recipients hospitalized with naturally acquired WNV encephalitis provided data to characterize the clinical symptoms, results of diagnostic studies, and outcomes. RESULTS: Eleven transplant recipients were identified (4 kidney, 2 stem cell, 2 liver, 1 lung, and 2 kidney/pancreas). Seven were directly admitted to 1 of the 2 hospitals in the study, and 4 were referred to 1 of these centers from regional hospitals. All but 1 patient had a prodrome typical of WNV encephalitis in nonimmunosuppressed patients. Ten patients developed meningoencephalitis, which in 3 cases was associated with acute flaccid paralysis. One patient developed acute flaccid paralysis without encephalitis. Six patients had significant movement disorders including tremor, myoclonus, or parkinsonism. All patients had cerebrospinal fluid pleocytosis and WNV-specific IgM in the cerebrospinal fluid and/or serum. Cerebrospinal fluid cytologic studies (n = 5) showed atypical lymphocytes, some resembling plasma cells; however, flow cytometry (n = 3) showed that cells were almost exclusively of T-cell (not B-cell or plasma cell) lineage. Magnetic resonance images of the brain were abnormal in 7 of 8 tested patients, and electroencephalograms were abnormal in 7 of 7, with 2 showing periodic lateralized epileptiform discharges. Nine of 11 patients survived infection, but 3 had significant residual deficits. One patient died 17 days after admission, and autopsy findings revealed severe panencephalitic changes with multifocal areas of necrosis in the cerebral deep gray nuclei, brainstem, and spinal cord as well as diffuse macrophage influx in the periventricular white matter. A second patient died of complications of WNV encephalitis 6 months after hospital admission. CONCLUSIONS: Naturally acquired WNV encephalitis in transplant recipients shows diagnostic, clinical, and laboratory features similar to those reported in nonimmunocompromised individuals, but neuroimaging, electroencephalography, and autopsy results verify that these patients develop neurological damage at the severe end of the spectrum.

Adult↗

PubMed2004

Proximal nerve root spinal hemangioblastomas: presentation of three cases, MR appearance, and literature review.

BACKGROUND: Hemangioblastomas (HBLs) are relatively uncommon tumors of uncertain histogenesis usually located in the cerebellum or spinal cord. Much less frequently they are identified in extramedullary locations including the filum terminale, proximal nerve roots, or even distal nerves of the peripheral nervous system (PNS). PNS cases not only present diagnostic challenges but also raise interesting questions regarding the common cell of origin for these CNS and PNS neoplasms. Few studies have detailed the neuroimaging characteristics of the rare extramedullary variants. METHODS: Neuroimaging and intraoperative findings of three recent cases of proximal nerve root HBLs are described. The English language literature on extramedullary HBLs is reviewed and discussed, particularly in regards to magnetic resonance (MR) findings and association with von Hippel-Lindau Syndrome (VHL). RESULTS: All 3 of our cases had prominent vessels present within the subarachnoid space on MR scans and all lesions enhanced. All were of intermediate or mildly decreased signal intensity on the T1-weighted images before contrast and were either iso- or hyperintense to spinal cord on the T2-weighted images. Two had probable cystic areas on MR, and all had cystic areas on histologic evaluation. CONCLUSION: These neuroimaging characteristics can serve to distinguish HBLs from the more common benign nerve sheath tumors with which they are most frequently confused. Less than half of all extramedullary HBLs are diagnosed in patients with known VHL. It is important to consider HBLs in the differential diagnosis, as they are vascular and have the propensity for causing significant blood loss at surgery.

Aged↗

PubMedDate not supplied

Free DICOM image viewing and processing software for your desktop computer: what's available and what it can do for you.

Whether or not a radiology department is "filmless," there is often a need to store images digitally for teaching or presentation purposes. Most computed tomographic and magnetic resonance images are in the Digital Imaging and Communications in Medicine (DICOM) 3 format, which has many advantages; however, these files can be very large and rapidly consume storage space. Converting DICOM files to smaller file formats such as the Joint Photographic Experts Group (JPEG) format can save space and allow insertion of images into presentations created with software such as Microsoft PowerPoint. Some picture archiving and communication systems can convert images from DICOM to other formats; however, many free options are also available. The World Wide Web was searched for free DICOM image viewing or processing software, and programs that were thought to be user-friendly and compatible with the Microsoft Windows operating systems were evaluated. There are many free programs that enable manipulation and processing of DICOM images on a desktop computer, allowing the user to easily window images and convert them to a smaller and more usable format, such as JPEG.

Humans↗

PubMedDate not supplied

Informatics in radiology (infoRAD): free DICOM image viewing and processing software for the Macintosh computer: what's available and what it can do for you.

It is often necessary for radiologists to use digital images in presentations and conferences. Most imaging modalities produce images in the Digital Imaging and Communications in Medicine (DICOM) format. The image files tend to be large and thus cannot be directly imported into most presentation software, such as Microsoft PowerPoint; the large files also consume storage space. There are many free programs that allow viewing and processing of these files on a personal computer, including conversion to more common file formats such as the Joint Photographic Experts Group (JPEG) format. Free DICOM image viewing and processing software for computers running on the Microsoft Windows operating system has already been evaluated. However, many people use the Macintosh (Apple Computer) platform, and a number of programs are available for these users. The World Wide Web was searched for free DICOM image viewing or processing software that was designed for the Macintosh platform or is written in Java and is therefore platform independent. The features of these programs and their usability were evaluated. There are many free programs for the Macintosh platform that enable viewing and processing of DICOM images.

Microcomputers↗

PubMedDate not supplied

It's not a cervical lymph node, it's a vein: CT and MR imaging findings in the veins of the head and neck.

The anatomy and imaging appearances of the veins of the head and neck can vary considerably, and normal veins may mimic disease processes at computed tomography (CT) and magnetic resonance (MR) imaging. On unenhanced CT scans, aberrant veins may be difficult to differentiate from lymph nodes or other pathologic conditions. Even at contrast material-enhanced CT, differences in venous enhancement or the mixing of opacified with nonopacified blood can lead to confusion, particularly if the vein is focally dilated. Similarly, the size and signal intensity of head and neck veins may vary at MR imaging due to slow or turbulent flow or variable enhancement, resulting in misdiagnosis. A thorough understanding of the normal venous anatomy and common variants is necessary to properly differentiate an unopacified or focally dilated vein from lymphadenopathy or some other disease entity and can help the radiologist avoid the erroneous interpretation of findings.

Diagnosis, Differential↗