Magnetic resonance imaging of the brain in Williams-Beuren syndrome.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
M Heller
Publications and source records attributed to M Heller.
[MR angiography of pelvic arteries].
During the last years, magnetic resonance angiography (MRA) has become a widely used modality for intracerebral and carotid artery imaging. Due to technical limitations, the clinical impact of MRA in the iliofemoral arteries has been rather poor. New developments in MRA like ECG-triggered sequences and the occurrence of contrast-enhanced MRA has overcome most of these limitations. Therefore, a major advance in clinical use of these diagnostic tools can be predicted. This paper discussed the advantages of ECG-gated 2D-Phase contrast, ECG-gated 2D-Time-of-Flight and contrast enhanced FLASH 3D angiography sequences from a clinical point of view. 2D-PC-MRA is a robust technique, which provides an overview of the iliofemoral artery system in less than 5 minutes. Limitations are the true 2D impression of the sequence and the partial venous overlay. 2D-TOF-MRA on the other hand is time consuming, however it enables 3D reconstruction and effective venous suppression can be applied. Contrast enhanced MRA as the third sequence discussed provides high resolution images in less than 30 sec. However contrast bolus timing might be a problem. In conclusion the authors suggest a combination of 2D-PC-MRA and additional 2D-TOF sequences at questionable vascular areas as the modality of choice, due to the fact, that MRA of the iliofemoral arteries ist mostly only one step of a complete lower limb examination. Contrast MRA might become the method of choice in the future however problems with multiple contrast injections and upper limits of contrast dose have to be solved.
Adult↗
Quiz case of the month. Boerhaave's syndrome.
Explore the source record for details and available documents.
Adult↗
MRI of the nasal cavity, the paranasal sinuses and orbits in Wegener's granulomatosis.
The purpose of this study was to evaluate diagnostic MRI criteria in Wegener's granulomatosis of the nasal cavity, the paranasal sinuses and orbits. Between March 1991 and January 1996, 62 patients with biopsy-proven Wegener's granulomatosis were studied with T1- and T2-weighted spin-echo (SE) sequences. In 32 patients coronal postcontrast T1-weighted images were obtained. Mucosal thickening of the nasal cavity and paranasal sinuses was demonstrated as high-intensity lesions on T2-weighted SE sequences in 57 patients (92%). Of this group, inflammatory granulomatous tissue was found on biopsy in 30 patients (48%) in the nasal cavity and in 4 patients (6%) in the paranasal sinuses. In 23 patients (37%) biopsy revealed unspecific inflammatory changes without evidence of granulomatous tissue. In 14 patients (23%) granulomas were depicted as low-signal intensity lesions on T1- and T2-weighted SE sequences in the paranasal sinuses and orbits. In 5 patients (8%) osseous destruction was found. After gadolinium injection, 12 of 14 granulomas showed inhomogeneous signal enhancement. In two granulomas no enhancement was found. The MRI technique is helpful in the diagnosis of patients with Wegener's granulomatosis. In the initial inflammatory process of Wegener's granulomatosis, it is not possible to differentiate between mucosal inflammation and granulomatous tissue in MRI. In the later stage of granulomatous transformation, granulomas can be depicted as low-signal-intensity lesions. Therefore, Wegener's granulomatosis should be included in the differential diagnosis of patients with low-signal-intensity lesions on T1- and T2-weighted SE sequences of the nasal cavity, paranasal sinuses and orbits.
Adult↗
Severe hemoptysis requiring lobectomy in an 11-year-old patient with Kartagener's syndrome.
The case of a young girl with severe hemoptysis in a Kartagener's syndrome is described. Because bronchoscopy failed to locate the origin of the bleeding, preoperative angiography was performed. The patient was treated by resection of the middle lobe. The bronchus wall was located as the origin of bleeding.
Angiography, Digital Subtraction↗
Factors affecting success of embryo collection and transfer in a transgenic goat program.
During a goat transgenic program that took place in Israel from July 1995 to February 1996, Saanen (n = 343) and Nubian x Damascus (n = 378) crossbred goats of mixed ages were used as donors (n = 433) and recipients (n = 288). The effects of season, age, number of surgical procedures, previous hormonal treatments and ovulation rate on the number of microinjectable embryos collected were studied. Likewise, the effects of these parameters on the pregnancy rate as well as the number of embryos transplanted, endogenous progesterone concentrations and exogenous progesterone supplementation were studied in recipient does. Following superovulation with ovine follicle stimulating hormone, 85% of the does responded with 13.6 +/- 5.7 (mean +/- S D) ovulations/doe. Age, month and number of previous hormonal treatments significantly affected the ovulation rate. The average recovery rate was 70%, and it was affected only by the ovulation rate. Pronuclei were visualized in about 30% of the flushed embryos (including unfertilized ova), and those were microinjected with human serum albumin gene construct. About 68% of the injected embryos underwent at least one division during an overnight incubation, and those embryos were transferred, giving about 2.0 transferred embryos per ovulated donor. Of the recipients, 86% responded following synchronization with 3.1 +/- 1.6 (mean +/- S D) ovulations per doe. Breed and month had a significant effect on the ovulation rate. Two or three microinjected embryos were transferred to each recipient, resulting in more than a 40% pregnancy rate during September to November. Lower pregnancy rates were obtained before and after that period. By monitoring plasma progesterone concentrations in the recipients it was found that progesterone concentration was correlated with the ovulation rate. However, the pregnancy rate was not affected by progesterone concentration. During January and February, 30 to 50% of the recipients failed to develop functional corpora lutea (CL) following embryo transfer, which explained the lower pregnancy rate in those months. Of the 86 kids born 4 were transgenic.
Journal Article↗
Epidermolysis bullosa acquisita diagnosed by direct immunoelectron microscopy of the conjunctiva.
OBJECTIVE: To describe for the first time the direct immunoelectron microscopic pattern of immune deposits on the conjunctival basement membrane in epidermolysis bullosa acquisita (EBA). DESIGN: Case reports. PARTICIPANTS: Two patients. INTERVENTION: Epidermolysis bullosa acquisita associated with cicatrizing conjunctivitis. MAIN OUTCOME MEASURES: Direct immunofluorescence and direct immunoelectron microscopy without freezing on conjunctival and skin biopsy specimens, indirect immunofluorescence, Western immunoblot analysis. RESULTS: Results of direct immunoelectron microscopic examination of the conjunctiva showed the presence of immune deposits in the anchoring fibril zone, just beneath the lamina densa, in both patients. This finding was the same as the direct immunoelectron microscopic pattern shown in the skin of these patients, which is known to be very specific for EBA. Direct immunofluorescence was positive in the conjunctiva of only one patient. Indirect immunofluorescence and Western immunoblot analysis failed to detect circulating autoantibodies. CONCLUSIONS: Direct immunoelectron microscopy on the conjunctiva is a useful diagnostic tool to differentiate EBA from other related autoimmune mucocutaneous blistering diseases.
Adult↗
Ultrasound for the detection of foreign bodies in human tissue.
STUDY OBJECTIVE: To determine the accuracy of detection of wood and plastic foreign bodies in human tissue by relatively inexperienced clinicians using typical ultrasound equipment. METHODS: Uniform wood and plastic foreign bodies were placed through small punctures into recently amputated human legs. Identical control punctures contained no foreign bodies; the sequence of foreign bodies and controls for the puncture sites was randomized. A second blinded investigator scanned each puncture site with a 7.5-MHz ultrasound probe to determine the presence or absence of foreign material. RESULTS: Eighty punctures were scanned. Ultrasound detected 44 of 53 foreign bodies (83% sensitivity). Wood foreign bodies were detected 25 of 27 times (93%) and plastic foreign bodies 19 of 26 times (73%; P = 13). Overall, there were 11 false-positive readings (59% specificity). CONCLUSION: Ultrasound is imperfect but may be useful in screening for superficial foreign bodies in human tissue. Clinical utility in the ED setting remains to be tested.
Chi-Square Distribution↗
Applications for ultrasonography in the emergency department.
The primary emergency applications of diagnostic ultrasonography are now reasonably well defined. Basic characteristics of the emergency department examination, including its rapid and highly focused nature, determine both the limitations and advantages of this technique. As greater experience and more advanced technologies develop in the emergency department setting, the role of ultrasonography will likely expand into areas that are not generally practiced today. Doppler technology, especially, promises to provide the emergency department physician of the future an even more powerful tool for the rapid diagnosis of a variety of common and critical conditions.
Emergency Service, Hospital↗
[CT of the talus: the importance of 2- and 3-dimensional reconstructions].
PURPOSE: To evaluate the clinical value of sagittal 2D- and 3D-reformations of the talus with and without electronic disarticulation compared to axial slices. MATERIAL AND METHODS: 23 patients with suspected traumatic lesions of the talus underwent 26 diagnostic CT examinations. Axial slices, sagittal reformations, and 3D-reformations without and with electronic disarticulation were performed. The sagittal 2D- and both types of 3D-reformations were compared to the axial slices with regard to their diagnostic information. RESULTS: Axial slices showed involvement of articular facets in 25 cases. Sagittal and 3D-reformations after electronic disarticulation depicted 23 fractures (23/25), 3D-reformations without electronic disarticulation showed none (0/23). Subluxation of the talocalcaneal joint was only visualised on axial slices three times. One complete luxation of this joint was shown on axial slices, sagittal and 3D-reformations without disarticulation. It was not visualised on 3D-reformations after disarticulation. CONCLUSION: The diagnosis must be made based on the axial slices, supported by sagittal reconstructions. 3D-reformations after electronic disarticulation provide a graphic, detailed and readily recognised image of the anatomy of transchondral fractures, and are very helpful in preoperative planning.
Adolescent↗
[3D-CT angiography and duplex sonography compared to arteriography in carotid stenoses].
PURPOSE: To determine the value of 3D-CT angiography, duplex sonography in comparison to selective digital subtraction angiography for evaluation of carotid artery stenoses. METHODS: 30 patients with 51 stenoses of carotid artery underwent 3D-CT angiography, duplex sonography and angiography. Quantification of stenosis was determined according to the NASCET study and categorized into mild (0-29%), moderate (30-69%), severe (70-99%) and occluded (100%). RESULTS: The agreement of 3D-CT angiography with intraarterial digital subtraction angiography (DSA) was 62% (r = 0.89; p < 0.0001) and of duplex sonography with DSA was 77% (r = 0.94; p < 0.0001). Both modalities underestimated one occlusion as stenosed. In the evaluation of moderate and severe stenoses 3D-CT angiography showed an agreement with DSA in 50% (duplex: 88%) and 55% (duplex: 89%) respectively and was inferior to duplex sonography. CONCLUSION: 3D-CT angiography is inferior to duplex sonography in the evaluation of carotid stenosis and not useful as a screening or reference examination.
Aged↗
[Digital chest x-rays with a selenium detector: a prospective comparison with a conventional film-screen combination].
PURPOSE: To compare a new digital chest radiography system that uses amorphous selenium as the x-ray detector, with conventional radiography for the detection of pathological alterations of the chest. MATERIAL AND METHODS: Two observers analysed pairs of posteroanterior and lateral chest radiographs of 95 patients. One pair of radiographs was obtained with the digital selenium chest radiography system, and the other with conventional film-screen technique. 9 criteria were rated using a 4 point scale. Technical parameters were standardised. Radiation dose was measured in both techniques and compared. RESULTS: A total of 855 criteria were rated. 740 findings were diagnosed in accordance on both techniques (740/855 = 87%). 115 criteria (115/855 = 13%) showed deviations. The mean radiation dose for the selenium detector was 0.02 cGy and for the conventional system 0.11 cGy. CONCLUSION: The exposure of radiation is lower using a selenium x-ray detector compared to conventional film-screen technique in chest radiography. The digital selenium system performs well in a clinical setting, providing visualisation of pathological findings as good as a standard screen-film system.
Adult↗
[Magnetic resonance tomography in the diagnosis of mandibular osteomyelitis].
PURPOSE: A prospective study of the value of MRI in the diagnosis of osteomyelitis of the mandible with special reference to the suitability of different MR sequences. MATERIAL AND METHODS: In 13 patients, average age 55 years (12-82), with clinical suspicion of osteomyelitis of the mandible, 18 MRI examinations were carried out (STIR, TSE T2, proton and SE T1 weighted scans with and without contrast, slice thickness 3.5 to 6 mm). Image quality of the sequences was evaluated as well as the suitability of the various sequences for showing the lesion, its location and extent. Activity of the osteomyelitis was judged by the degree of contrast uptake and was correlated with 3-phase bone scintigraphy and with histological findings. RESULTS: In 9 of the 14 cases the findings on MRI and of the scintigraphy agreed with the histology. In two patients the activity of the inflammatory process was exaggerated by the MRI. In another follow-up examination it was slightly underestimated. All lesions were shown to be highly active by the histology were recognized as such by MRI. For the localisation and recognition of the extent of the inflammatory processes STIR sequences and T1 weighted non-enhanced SE sequences proved the most suitable. Contrast medium is essential to evaluate the inflammatory activity. CONCLUSION: MRI is a sensitive diagnostic method; it is as good as 3-phase bone scintigraphy in demonstrating osteomyelitis of the mandible and of its activity but is superior for showing the pathological anatomy.
Adolescent↗
[CT morphology of fractured thoraco-lumbar vertebrae after transpedicular spongiosaplasty and use of internal fixator].
PURPOSE: An analysis of the CT morphology of fractured thoraco-lumbar vertebrae after treatment with internal fixation and transpedicular spongiosaplasty (SP). MATERIAL AND METHOD: 30 patients were examined following trauma and surgery after about 12 and 30 months by means of CT. The following were evaluated: width of the spinal canal; height of the vertebra and intervertebral space; degree of kyphosis; position, size and appearance of the SP and of the vertebral body. RESULTS: The width of the spinal canal was reconstituted in 91%; in 83% the anterior vertebral margin and in 35% the intervertebral space was reduced. A kyphosis of 8.9 degree was found on the followup examination. The SP showed a reduction in size (18/30) or could no longer be defined (6/30). Hypodense areas (28/30) with cavitation (12/30) were found in the vertebral body and the SP could be identified by a sclerotic margin (22/30). CONCLUSION: Treatment by this form of therapy was successful, reaction of the vertebral body against the spongiosaplasty could be identified.
Adolescent↗
[Midterm follow-up after Cragg stent placement in iliac arteries].
PURPOSE: Evaluation of midterm success and patency rates after placement of Cragg stents in iliac arteries. MATERIAL AND METHODS: During a period of 26 months 16 patients, with a total of 19 iliac lesions were treated percutaneously by placement of 20 stents. Indications of stent placement were iliac occlusion in 4 cases and high-grade iliac stenoses in 15 cases. Indication for stent placement in the stenotic lesions were insufficient results following balloon angioplasty in 11 cases and extensive dissection in 4 cases. RESULTS: The ankle-brachial index was improved from 0.53 +/- 0.28 to 0.85 +/- 0.26 immediately after the intervention and was 0.80 +/- 0.15 at 16 months follow-up. Cumulative patency rate was 71% after 12 months. CONCLUSION: The occlusion and restenosis rates are high. Disadvantages of Cragg stents are low flexibility and a large bore introducer system. The radiopacity of the Cragg stent is advantageous for fluoroscopic positioning.
Aged↗
[Comparison of T2-weighted turbo spin-echo and ultrafast HASTE sequence in the diagnosis of cervical myelopathies and spinal stenoses and static and kinematic MRT of the spine].
PURPOSE: The purpose of this study was to compare HASTE-sequence with T2-weighted TSE-sequence in the detection of cervical myelopathy and cervical spinal stenosis in kinematic MRI. METHODS: 24 patients with degenerative disease of the cervical spine were studied. Images were evaluated according to the following criteria: artifacts, delineation of the vertebra, disks and degenerative changes, grade of spinal stenosis (grade 0-3) and evaluation of the cervical spinal cord. RESULTS: Due to image blurring and artifacts, evaluation and delineation of the cervical spine was possible in all cases in the T2-weighted TSE-sequence, but only in 23 of 24 patients using HASTE-sequence. Differentiation between osteophytes and disks was obtained in most cases (23/24) in the T2-weighted TSE-sequence but none in the HASTE-sequence. Cervical myelopathy was observed in 4 patients in T2-weighted TSE images but only in two cases using HASTE-sequence. Compared to T2-weighted TSE-sequence spinal canal stenosis was underestimated using HASTE-sequence. CONCLUSION: T2-TSE-sequence is superior to HASTE-sequence in the delineation of anatomical structures of the cervical spine, the grading of cervical spinal stenosis and the evaluation of cervical myelopathy.
Adult↗
[MR myelography in spinal canal stenosis].
PURPOSE: The purpose of this prospective study was to evaluate the clinical value of 3D-MR-myelography (3D-MRM) in comparison to myelography and intra-operative findings. MATERIAL AND METHODS: 25 patients with suspected lumbar spinal canal stenosis were studied via myelography and 3D-MRM (volume-data set, 3D-FISP sequence, TR 73 ms, TE 21 ms, flip angle 7 degrees, sagittal slices) besides the routinely acquired sagittal and axial T1- and T2-weighted images. Diagnoses were made by two radiologists and one neurosurgeon without knowing the clinical history and symptoms, in two separate sessions. Results were compared to intraoperative findings. RESULTS: 3D-MRM has the same diagnostic sensitivity (25/25 = 100%) as conventional X-ray myelography (25/25 = 100%) compared to intraoperative findings, but is not invasive and shows more diagnostic details than myelography. Especially in cases of high-grade spinal canal stenosis there is often a lack of intrathecal contrast medium distally of the stenosis. CONCLUSION: 3D-MRM is as good as conventional myelography in predicting intraoperative findings in patients with lumbar spinal canal stenosis. This new method is non-invasive and can be performed routinely on an outpatient basis.
Adult↗
MR imaging of the central nervous system in diving-related decompression illness.
PURPOSE: This investigation was conducted to determine whether MR imaging showed cerebral or spinal damage in acute diving-related decompression illness, a term that includes decompression sickness (DCS) and arterial gas embolism (AGE). MATERIAL AND METHODS: A total of 16 divers with dysbaric injuries were examined after the initiation of therapeutic recompression. Their injuries comprised: neurological DCS II n = 8; AGE n = 7; combined cerebral-AGE/spinal-DCS n = 1. T1- and T2-weighted images of the brain were obtained in 2 planes. In addition, the spinal cord was imaged in 7 subjects. The imaging findings were correlated with the neurological symptoms. RESULTS: MR images of the head showed ischemic cerebrovascular lesions in 6/8 patients with AGE but showed focal hyperintensities in only 2/8 divers with DCS. Spinal cord involvement was detected in 1/7 examinations, which was the combined cerebral-AGE/spinal-DCS case. There was agreement between the locations of the documented lesions and the clinical manifestations. CONCLUSION: MR readily detects cerebral damage in AGE but yields low sensitivity in DCS. A negative MR investigation cannot rule out AGE or DCS. However, MR is useful in the examination of patients with decompression illness.
Adult↗