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J Laubenberger

Publications and source records attributed to J Laubenberger.

At least 55 records · Page 3Linked to original sources
PubMed1997

Multiple giant fibroadenomas: clinical presentation and radiologic findings.

We describe the case of a 25-year-old Caucasian woman suffering from unilateral enlargement of the breast. Morphologic evaluation of various imaging modalities including mammography, ultrasound, and magnetic resonance imaging suggested a benign tumor embedded in stromal tissue. The time course of the Gd-DTPA uptake in dynamic magnetic resonance imaging, however, was also compatible with a malignant lesion. Postoperative pathological examination revealed multiple giant fibroadenomas, a rare disease, usually encountered in black female adolescents. Radiologic presentation, differential diagnosis, and morphologic findings are discussed, and a review of the literature is contained herein.

Adult↗
PubMed1997

Comparative diagnostic accuracy of magnetic resonance imaging and immunoscintigraphy for detection of bone marrow involvement in patients with malignant lymphoma.

PURPOSE: To compare the diagnostic accuracy of magnetic resonance imaging (MRI) and immunoscintigraphy (IS) for detection of bone marrow infiltration in malignant lymphoma. PATIENTS AND METHODS: In 32 patients with Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL), MRI of the axial skeleton and whole-body IS using technetium-99m (99mTc)-labeled monoclonal antibodies were reviewed and compared with iliac crest biopsies. Criterion for marrow infiltration was a positive biopsy or concordant positive results of MRI and IS. RESULTS: In 16 patients (50%), MRI, IS, and iliac crest biopsies were negative for marrow infiltration. Iliac crest biopsy showed infiltration in only four patients (13%). Infiltration was missed in two of 32 patients with IS and in one patient with MRI. In one additional patient, MRI was false-positive because of pelvic hematopoietic hyperplasia. A subset of nine patients (28%) with negative biopsies had bone marrow involvement according to MRI and IS with identical location and pattern of infiltration. In eight of these nine patients, diagnostic imaging indicated marrow involvement only in noncrest marrow. Subsequent biopsy confirmed infiltration in five patients. The clinical course suggested true-positive imaging results in the remaining four patients. Two patients (6%) remained equivocal. Overall concordance of MRI and IS for marrow infiltration was 88% (28 of 32 patients). CONCLUSION: Diagnostic imaging is essential for optimal staging in malignant lymphoma, as blind biopsies appear to have low sensitivity for bone marrow infiltration because of frequent involvement in noncrest marrow. both imaging modalities show a high rate of detection of bone marrow infiltration.

Adolescent↗
PubMed1997

Measurement of femoral antetorsion and tibial torsion by magnetic resonance imaging.

Several methods for measuring femoral and tibial torsion by CT have been described since 1980. Alternative methods of measurement to CT are needed to avoid irradiating young patients facing derotation osteotomy. In this study, MRI was used to quantify femoral and tibial torsion in normal adult volunteers, firstly with transverse sections analogous to those of CT in order to establish reference values; and secondly, with sections along the axis of the neck of femur to assess the influence of the orientation of the slices on the measured values. The images were acquired using fast T1 weighted gradient echo sequences in 0.2 and 1 T magnets. Average femoral antetorsion (CT-analogous method) was 10.4 degrees (average side difference = 4.6 degrees); average tibial torsion was 41.7 degrees (average side difference = 6.1 degrees). A steeply inclined slice along the axis of the femoral neck gave a mean measurement of the angle of antetorsion that was significantly higher than the mean obtained from either slightly inclined or transverse sections (16.7 degrees vs 12.1 degrees and 11.2 degrees, respectively, p < 0.001). In conclusion, MRI provides an alternative to CT in the measurement of femoral and tibial torsion. MRI enables one to orientate the slice along the axis of the femoral neck, thus obtaining a single cross-section of the entire neck. However, the normal range of measurements will vary according to the plane of image.

Adult↗
PubMed1996

Central pontine myelinolysis: clinical presentation and radiologic findings.

Central pontine myelinolysis (CPM) is a neurologic disorder once thought to be uniformly fatal. With the introduction of CT and MRI there was an increasing number of reports on nonfatal cases of CPM. Nearly all reports on nonfatal cases describe severe clinical syndromes with tetraparesis, bulbar palsy, and coma. We reviewed nine patients with CPM and compared the size of the pontine lesion on MRI and CT with the severity of clinical presentation. Clinical presentation of CPM was highly variable: The symptoms ranged from severe neurologic disorders to mild neurologic disturbances only. Two of nine patients died from CPM. The size of the pontine lesion did not correlate with the severity of the neurologic illness or the final outcome. Mild forms of CPM might be difficult to diagnose clinically. This applies even more for patients with underlying diseases such as Wernicke's encephalopathy, which in itself might cause a clinical picture similar to that of CPM. Central Pontine Myelinolysis is a major differential diagnosis in acute neurologic deterioration indicating pontine damage. Magnetic resonance imaging is the decisive diagnostic tool for CPM.

Adult↗
PubMed1996

[Morphology of the carpal tunnel. Movement studies in patients with constriction symptoms and healthy probands using MR tomography].

The morphological correlation of the phenomenon of increased pressure in the carpal tunnel during wrist flexion and extension--as has been proved though measurements using wick-catheters--was studied in healthy subjects (n = 15) and symptomatic patients with carpal tunnel syndrome (n = 15). Our own measurements using magnetic resonance imaging (MRI) showed that there is a significant reproducible decrease in carpal tunnel diameter when the wrist is held in position of either flexion or extension. During flexion the diameter is decreased at the pisiformes and hamate level as well as it is lowered during extension at the pisiformes level. This might explain the rise in carpal tunnel pressure and thus the consecutive negative influence on the median nerve. Proximal swelling, distal flattening and increased signal intensity of the median nerve as well as the palmar bulging of the flexor retinaculum at the level of the hook of the hamate and at the level of the pisiformes were significantly higher in patients with carpal tunnel syndrome than in normal volunteers (from p < 0.05 to p < 0.001). In post-operative follow-up examinations of 13 patients with no clinic symptoms the distal flattening of the median nerve normalized in 94% within 3 months. The increased signal of the median nerve on T2-weighted images decreased postoperatively in 2/3 of the patients, whereas the motor latency of the median nerve recovered only in 39% of our patients who had 100% partial or complete clinical benefit. These findings imply that postoperative imaging may be helpful for evaluating the success or failure of surgical treatment.

Adult↗
PubMed1996

[Ultrasound and mammography follow-up of findings after breast saving operation and adjuvant irradiation].

AIM: The aim of our controlled retrospective study was to assess the diagnostic value of sonography for detection and characterisation of changes compared to mammography and palpation. METHOD: In 80 patients sonographic and clinical follow-up examinations were performed every 3 to 6 months, mammography examinations were performed every 6 to 12 months during the first 2 years after breast-preserving therapy (BPT) and irradiation. Extension, echogenicity, and configuration of lesions in sonography, and semiquantitiative description of diffuse or circumscribed changes in mammography were the basis of comparative follow-up observation. RESULTS: Postoperative seromas and haematomas, initially presenting echo-free or as hypoechoic lesions, showed an increase in echogenicity within 18 months after irradiation. Fat necrosis occurred in 9.5% of patients, lymph cysts developed in 4%, granuloma in 3%, recurrence of neoplasma in 1.6%. The diffuse loss of transparency in mammography that was associated with radiation therapy, showed a peak 6-12 months after irradiation. CONCLUSION: Sonography and sonographic guided puncture are mandatory tools to characterise circumscribed unclear lesions after breast-conserving therapy and irradiation in specialised centers. We recommend a 6-month interval for combined sonography, palpation, and mammography within the first 2 years after BPT and irradiation, because shorter control intervals did not result in relevant diagnostic advantages.

Adult↗
PubMed1996

[Computerized tomography findings score in the differentiation of adrenal tumors in patients with extra-adrenal malignomas].

PURPOSE: In a retrospective study the diagnostic accuracy of computed tomography for the differentiation of benign from malignant adrenal masses in patients with extra-adrenal malignancies was evaluated. For this differentiation a new score system was tested. PATIENTS AND METHODS: Size, density, structure, and borders of adrenal masses in 60 patients with extra-adrenal tumours were analysed and scored. The single criteria and the total score values were correlated with the final diagnosis achieved either by histology or by follow-up CT examinations. RESULTS: Score values above 4 indicated always metastases and score values below 2 were benign lesions. An overlap occurred at score values between 2 and 3 resulting in an overall accuracy of 83.3%. CONCLUSION: Single CT criteria are not reliable enough to differentiate benign from malignant adrenal lesions: better results are achieved by using our scoring system.

Adenoma↗
PubMed1996

HIV-related metabolic abnormalities in the brain: depiction with proton MR spectroscopy with short echo times.

PURPOSE: To analyze brain metabolite changes in human immunodeficiency virus (HIV)-positive neurologically asymptomatic patients and patients with acquired immunodeficiency syndrome (AIDS) dementia complex (ADC). MATERIALS AND METHODS: Twelve ADC patients, 11 HIV-positive asymptomatic patients, and 10 healthy control subjects underwent magnetic resonance (MR) imaging and proton MR spectroscopy with short echo times. Changes in N-acetyl aspartate (NAA), choline (Cho), myoinositol (MI), and creatine (Cr) were presented as ratios with Cr as the reference. RESULTS: Statistically significant (P < .05) differences were noted. In ADC patients, all with MR findings of brain atrophy and diffuse white matter disease, NA/Cr decreased (white matter, -31.8%; gray matter, -22.3%), MI/Cr increased (white matter, +42.5%; gray matter, +51.8%), and Cho/Cr increased (white matter, +20.6%; gray matter, +51.7%) compared with healthy control subjects. In HIV-positive asymptomatic patients, NA/Cr decreased slightly (white matter, -6.9%; gray matter, -5.1%), MI/Cr increased slightly (white matter, +13.7%; gray matter, +10.7%), and Cho/Cr did not change. CONCLUSION: ADC has a uniform pathologic metabolic pattern that affects NAA, MI, and Cho. Proton MR spectroscopy with short echo times helps detect early abnormalities in clinically asymptomatic patients.

AIDS Dementia Complex↗
PubMed1996

Magnetic resonance imaging (MRI) for detection of active sacroiliitis--a prospective study comparing conventional radiography, scintigraphy, and contrast enhanced MRI.

OBJECTIVE: Sacroiliitis is often difficult to diagnose in the absence of radiographic alterations. For the diagnosis of active sacroiliitis, plain radiography, scintigraphy, and contrast enhanced magnetic resonance imaging (MRI) were evaluated in a prospective study. METHODS: In 44 consecutive patients with complete clinical and laboratory evaluation, plain radiographs, quantitative sacroiliac (SI) scintigraphy, and MRI were performed to evaluate the contribution of these imaging techniques to the diagnosis of active sacroiliitis. Scintiscanning and MRI were done in 20 control subjects to define the normal range of imaging findings. We determined the sensitivity and specificity for each imaging method using a reference standard based on clinical symptoms of inflammatory low back pain with or without laboratory signs, and on clinical and radiographic followup during 1.5-2.5 years to confirm diagnosis. RESULTS: MRI was most sensitive (95%) and superior to quantitative SI scintigraphy (48%) or conventional radiography (19%) for the detection and confirmation of active sacroiliitis. For the assessment of inflammatory signs, MRI had higher specificity (100%) than scintigraphy (97%) or plain radiography (47%). At repeat MRI after 2-30 months, there was persistent pathologic signal intensity in the subchondral bone area despite clinically successful antiinflammatory drug therapy. CONCLUSION: For the assessment of active changes in the synovial portion and the subchondral bone marrow, contrast enhanced MRI is superior to quantitative SI scintigraphy or conventional radiography. MRI picks up an additional 75% of early cases not diagnosed by plain radiography. Scintigraphy is only of limited value. Persistent pathologic signal intensity in the subchondral bone marrow seems to be closely associated with previous inflammatory episodes, thus limiting specificity of MRI for active sacroiliitis. Based on our findings we suggest an algorithm for the evaluation of patients with suspected active sacroiliitis.

Adolescent↗
PubMed1995

Breath-hold projection magnetic resonance-cholangio-pancreaticography (MRCP): a new method for the examination of the bile and pancreatic ducts.

Breath-hold MR cholangio-pancreaticography using the RARE method was evaluated as a noninvasive alternative to direct cholangio-pancreaticography in 30 healthy volunteers and in 30 patients with various diseases of the respective duct systems. In contrast to 3D MR cholangiography, RARE MRCP generates projection images requiring a 4-s acquisition time and no postprocessing. Diagnostic information gained from the cholangio-pancreaticograms was fully equivalent to that of conventional x-ray imaging by invasive procedures. Additional information was gained whenever endoscopic access was impossible and/or cystic malformations were present.

Adult↗
PubMed1995

Haemangiomatosis in children: value of MRI during therapy.

MRI findings of 18 examinations of six children with haemangiomatosis and one with extended arteriovenous malformation are reported. Structures involved were the liver, liver and lung, periorbital area and the thigh. Response to interferon therapy, in particular, was assessed. With MRI the disease can be characterized and the extent of the lesions and size of the haemangiomas measured. Coronal views provide excellent demonstration of the involved structures in liver and lung haemangiomatosis. Two children showed response to interferon therapy with a reduction in lesion size and subsequently in number. Signal intensity decreased slightly on T2-weighted images. During treatment, however, no definitive fibrotic zones were seen. Following complete regression, signal intensity of the liver parenchyma was homogeneous in both weightings, that is, no fibrotic areas were visible 18 months after the beginning of treatment. Two children showed no response and one child died from congestive cardiac failure. The periorbital haemangioma was reduced in size and the lesion in the thigh might be classified as an arteriovenous malformation. In children MRI can replace CT as it is a reliable imaging modality for diagnosing haemangiomatosis and monitoring therapy.

Child↗
PubMed1995

Preoperative CT and MR imaging of inferior vena cava leiomyosarcoma.

We investigated the radiological findings of five patients with primary leiomyosarcoma of the inferior vena cava (IVC) comparing cavography, computed tomography (CT), and magnetic resonance imaging (MRI). The radiographic presentation ranged from an intraluminal lesion with obstruction of the IVC to a tumor mass extending from the media musculature into the surrounding perivascular tissue with only slight protrusion into the lumen. The lesions were associated with late or few symptoms. Pathognomonic radiological findings could not be established. In cases with an extraluminal growth a lobulated, well-defined, encapsulated tumor with an inhomogeneous contrast uptake is characteristic in CT studies. Additional information was provided by MRI. Leiomyosarcomas with extraluminal involvement showed homogeneous intermediate signal intensity (SI) on T1-, and mixed intermediate/high SI on T2-weighted images. In cases with predominantly intraluminal growth, both CT and MRI demonstrated the IVC to be dilatated and allowed to differentiate between tumor extent and obliterating thrombosis. Modern imaging modalities allow an early and accurate pre-operative diagnosis resulting in a higher rate of surgical resection and improvement of survival.

Adult↗
PubMed1995

Value of RARE-MRI sequences in the diagnosis of lymphangiomatosis in children.

Three patients suffering from extensive cavernous lymphangiomatosis are presented here. They were examined by MRI using RARE-MR hydrography (rapid acquisition with relaxation enhancement) as well as conventional spin-echo sequences. RARE sequences, which depict each fluid-filled lymphatic space, can be used for screening. RARE-sequences help to shorten investigation time, particularly in cases involving the skeleton. The imaging strategy can be changed according to the results of this sequence. It may be performed prior to spin-echo sequences and facilitates follow-up investigations. RARE sequences distinguish between lymphangiomatosis and hemangiomatosis, or a combination of the two.

Adult↗
PubMed1995

[NMR tomographic measurement of femoral ante-torsion and tibial torsion].

PURPOSE: A new MRI method for the measurement of femoral torsion and tibial torsion is presented. METHODS: Axial images were generated using a standard gradient echo sequence (FLASH 2D). Otherwise measurement of femoral and tibial torsion was performed according to an established CT method. RESULTS: The torsion angles measured using MRI were in accordance with the angles measured using the CT method. The MRI method was not more time-consuming than the CT method. CONCLUSION: In respect of radiation exposure, MRI determination of femoral and tibial torsion should be considered particularly in children and patients who have to undergo repeated torsion measurements.

Adolescent↗
PubMed1994

Proton magnetic resonance spectroscopy studies on human brain myo-inositol in hypo-osmolarity and hepatic encephalopathy.

BACKGROUND/AIMS: Recent in vivo studies using proton magnetic resonance (1H-MR) spectroscopy showed low levels of myo-inositol in the brain in hepatic encephalopathy; the pathogenetic relevance of this observation is unclear. METHODS: Myo-inositol and glutamine levels in the brain were studied in vivo by 1H-MR spectroscopy in patients with hypo-osmolarity and hepatic encephalopathy. RESULTS: A patient with severe plasma hypo-osmolarity (222 mOsm/L) had almost undetectable signals for myo-inositol and glutamine/glutamate in the brain. Both signals reappeared after normalization of plasma osmolarity, suggesting that both myo-inositol and glutamine were released as organic osmolytes from the brain. A decreased cerebral myo-inositol signal is also found in low-grade hepatic encephalopathy but is accompanied by an increased glutamine signal. Cirrhotics without hepatic encephalopathy have near-normal inositol signals, and patients with acquired immunodeficiency syndrome encephalopathy have increased inositol signals. CONCLUSIONS: The 1H-MR spectroscopic myo-inositol signal in the human brain predominantly reflects an osmosensitive inositol pool. It is hypothesized that its depletion in latent hepatic encephalopathy points to a disturbance of cell volume homeostasis in the brain as an early pathogenetic event. This may partly be caused by a hyperammonemia-induced glutamine accumulation in the brain.

Acquired Immunodeficiency Syndrome↗