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J Gaa

Publications and source records attributed to J Gaa.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Standardized sonographic examination of the hip joint].

AIM: We demonstrate a technique for examining the hip joint sonographically in a standardised way using sectional planes corresponding to the guidelines provided by the work group "Sonography of the Musculo-Skeletal System" of the German Society of Ultrasound (DEGUM). MRT-scans were used as a comparative standard. METHOD: The ultrasound examination was performed in the following standardised way: a transversal and longitudinal scan were done in the ventral region and additionally a longitudinal scan in the lateral region. In cases without pathological findings two standardised planes should be documented. In the case of pathological findings the picture should be documented in two standardised planes and compared to the corresponding contralateral site. An ultrasound examination standardised in this way facilitates a precise assessment of the ventral joint capsule, the bone structures, the ventral and lateral aspects of the glenoid cavity and the peri-articular soft tissue structures of the hip joint. RESULTS: An examination technique is presented which offers additional pictorial information, saves costs and is not harmful to the patient. CONCLUSION: The ultrasound examination of the hip joint can supply additional information about diseases and traumatic changes in this region. In paediatric hip disorders such as transient synovitis, septic arthritis, juvenile arthritis, Leg-Calvé-Perthes disease and slipped femoral epiphysis, the ultrasound examination can provide important additional information for the initial differential diagnosis and during follow-up.

Germany↗
PubMed2000

Evaluation of breath-hold contrast-enhanced 3D magnetic resonance angiography technique for imaging visceral abdominal arteries and veins.

RATIONALE AND OBJECTIVES: To evaluate the diagnostic value of breath-hold contrast-enhanced 3D magnetic resonance angiography (MRA) for assessment of the visceral abdominal arteries and veins in patients with suspected abdominal neoplasms. METHODS: Twenty-one patients underwent MR imaging on a 1.5 T unit using a body phased-array coil. MRA was performed with a 3D-FLASH sequence (TR 3.8 ms, TE 1.3 ms, flip angle 25 degrees, acquisition time 20 seconds), 8 to 12 seconds after an intravenous bolus injection of Gd-DTPA. The acquisition delay between the arterial and the portal venous phase was 12 seconds. The image quality and the degree of vascular involvement were evaluated using coronal source images and maximum intensity projection reconstructions. Diagnosis was confirmed by surgery/histology. RESULTS: Image quality was optimal in more than 85% of the patients (19/21 arterial phase and 17/21 portal venous phase). MRA correctly predicted vascular status in 20 of 21 patients (95%), with complete concordance between MRA results and surgical findings. In one patient with chronic pancreatitis, MRA demonstrated a false-positive finding that could not be confirmed surgically. CONCLUSIONS. Breath-hold contrast-enhanced 3D-MRA is a valuable technique for assessing visceral abdominal arteries and veins.

Abdomen↗
PubMed2000

Tracking down duodenopancreatic malignancy.

BACKGROUND: Malignant tumours of the duodenum are rare and often difficult to diagnose. Due to the small clinical experience with duodenal malignancies their prognosis is unknown and resection is the treatment of choice. CASE REPORT: Adding to a small series of incidental tumours, we report the case of a 65-year-old patient with primary extranodal (MALT-) lymphoma of the duodenum infiltrating the pancreatic head. The patient was admitted because of anaemia and epigastric discomfort with a history of Helicobacter-pylori associated gastric ulceration. Physical examination and bloodchemical values were otherwise normal. Endoscopy revealed duodenal ulceration but the biopsies taken from the ulceration did not give any evidence of malignancy or residual Helicobacter pylori infection. But MRT showed a circular intramural tumour of the duodenum. On laparotomy a large duodenal tumour adherent to the pancreatic head was found and a Whipple procedure was performed. CONCLUSION: Apart from describing the case of a rare lymphoproliferative disorder of the duodenum, this report illustrates the diagnostic difficulties with uncommon neoplasm's of the duodenopancreatic region and the value of MRT prior to resection of a duodenopancreatic mass.

Aged↗
PubMed2000

Pancreas picture of the month. Pancreatic manifestation of cystic fibrosis.

The Magnetic Resonance Cholangio Pancreatography (MRCP) provides within a few seconds complete information on cystic degeneration of the pancreas in patients with cystic fibrosis. The authors present a case report of cystic fibrosis with a pathognomonic magnetic resonance cholangio pancreaticography image of the pancreas.

Adolescent↗
PubMed1999

[Echo-planar diffusion-weighted MRI in the diagnosis of acute ischemic stroke: characterisation of tissue abnormalities and limitations in the interpretation of imaging findings].

INTRODUCTION: An accurate diagnosis is frequently difficult in early stroke. Diffusion-weighted (DW) magnetic resonance imaging (MRI) allows visualization of ischemic parenchyma and quantitative assessment of tissue changes before unequivocal abnormalities appear on T(2)-weighted MRI. METHODS: We analyzed 105 MRI examinations of patients with acute stroke (<24 h) with regard to patterns of abnormalities in T(2)-weighted and DW MRI. Furthermore we assessed the influence of artifacts related to DW echo-planar single-shot MRI on image interpretation. RESULTS: Depending on the time of patient assessment there were three partly overlapping T(2)/DW patterns: (1) in the very early phase (</=1.5 h after symptom onset) there was no T(2) abnormality and no definite abnormality of diffusion; (2) no T(2) abnormality and restricted diffusion (1.5-4 h); (3) T(2) hyperintensity and restricted diffusion (>/=3 h). Typical artifacts (susceptibility distortions, N/2 artifact, chemical shift artifact and eddy currents artifact) had to be considered when interpreting images. CONCLUSIONS: Provided typical artifacts are taken into consideration, echo-planar DW MRI allows a more precise diagnostic assessment in acute stroke.

Acute Disease↗
PubMed1999

Aortocaval fistula complicating abdominal aortic aneurysm: diagnosis with gadolinium-enhanced three-dimensional MR angiography.

With approximately 150 reported cases, fistulas between the abdominal aorta and inferior vena cava are rare. Preoperative clinical diagnosis of aortocaval fistula is difficult because the classical triad of abdominal pain, pulsatile abdominal mass, and abdominal machinery-like bruit may be absent in up to 50 % of patients. We report a case of aortocaval fistula complicating abdominal aortic aneurysm which was diagnosed preoperatively using breath-hold gadolinium-enhanced three-dimensional MR angiography.

Aorta, Abdominal↗
PubMed1999

MR imaging of pulmonary parenchyma with a half-Fourier single-shot turbo spin-echo (HASTE) sequence.

OBJECTIVE: To evaluate the utility of a half-Fourier single-shot turbo spin-echo sequence (HASTE) at depicting lung parenchyma and lung pathology. METHODS AND PATIENTS: A HASTE sequence was applied to five normal volunteers and 20 patients with various pulmonary disorders to depict the lung parenchyma. Images were acquired with ECG-triggering and breath-holding. In three volunteers, signal intensity measurements from lung parenchyma were performed using four sequences: (a) HASTE; (b) conventional spin echo; (c) fast spin echo; and (d) gradient echo. T2 maps were produced using the HASTE acquisition. RESULTS: Minimal respiratory or cardiac motion artifacts were observed. The signal-to-noise ratios from lung parenchyma were 27.8 +/- 5.4, 22.0 +/- 3.0, 15.3 +/- 0.9, and 6.0 +/- 1.9 for HASTE, spin-echo, fast spin-echo, and gradient echo sequences, respectively. The scan time for HASTE was 302 ms for each slice. The T2 values in the right lung and the left lung were 61.2 +/- 4.1 and 79.1 +/- 8.9 ms in systole and 92.6 +/- 5.8 and 97.5 +/- 12.2 ms in diastole, respectively (P < 0.05 diastole versus systole). The HASTE sequence demonstrated clearly various pulmonary disorders, including lung cancer, hilar lymphadenopathy, metastatic pulmonary nodules as small as 3 mm, pulmonary hemorrhage, pulmonary edema and bronchial wall thickening in bronchiectasis. CONCLUSION: Our preliminary results indicate that the HASTE sequence provides a practical means for breath-hold MR imaging of lung parenchyma.

Adult↗
PubMed1999

[Comparison of conventional and high resolution 2D RARE MRCP in diagnosis of pancreaticobiliary diseases].

PURPOSE: Evaluation of high-resolution 2D-RARE MRCP in the diagnosis of pancreaticobiliary diseases. MATERIALS AND METHODS: 23 patients with various pancreaticobiliary diseases were evaluated using conventional and high-resolution 2D-RARE sequences. RESULTS: High-resolution RARE MRCP allowed for improved delineation of biliary and pancreatic ducts at the expense of reduced signal-to-noise ratio. Pathological findings were significantly (p < 0.001) better demonstrated with high resolution RARE MRCP (score 1.65 +/- 0.54) as compared to the conventional RARE sequence (score 2.58 +/- 0.62). CONCLUSIONS: High-resolution 2D-RARE-MRCP improves the delineation of biliary and pancreatic ducts. This sequence should replace the conventional 2D-RARE sequence.

Adult↗
PubMed1999

[The value of magnetic resonance tomography (MRT), magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of pancreatic tumors].

PURPOSE: To prospectively evaluate the role of MRI including MR cholangiopancreatography (MRCP) compared to endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis of pancreatic cancer. MATERIAL AND METHODS: ERCP and MRI including MRCP were performed in 52 patients with suspected pancreatic cancer. MRCP was obtained using a single-shot RARE technique. The results of axial images and MRCP were compared to concurrently performed ERCP examinations. The standards of reference were the surgical and pathological findings, respectively. Image quality of MRCP was assessed using a three-step-score (1 = good, 2 = fair, 3 = nondiagnostic). RESULTS: In 88% of the cases the MRCP was of good quality. Only in 4% was MRCP non-diagnostic. The combination of MRI and MRCP showed an overall accuracy of 88%, whereas the overall accuracies of MRCP alone and ERCP were 80%, and 85%, respectively. The positive predictive values of MRI/MRCP, MRCP alone, and ERCP were 91%, 85%, and 88%, respectively. CONCLUSION: For the detection of pancreatic cancer MRI including MRCP is comparable to ERCP and can be regarded as the method of choice in patients with suspected pancreatic cancer. ERCP is the procedure of choice in patients with contraindications to MRI and in patients in whom additional therapeutic procedures are performed.

Adenocarcinoma↗
PubMed1999

[Combined use of MRI and MR cholangiopancreatography and contrast enhanced dual phase 3-D MR angiography in diagnosis of pancreatic tumors: initial clinical results].

PURPOSE: To evaluate the accuracy of a non-invasive "all-in-one" staging MR method in patients with pancreatic tumors. MATERIAL AND METHODS: 46 patients were prospectively evaluated by a combined MR imaging protocol including breath-hold T1- and T2-weighted pulse sequence, MRCP using a breath-hold 2D-RARE sequence, and breath-hold gadolinium-enhanced dual-phase 3D-MR angiography. RESULTS: All pancreatic tumors were detected by the combination of cross-sectional imaging and MRCP. In spite of the use of MRCP, definitive differentiation between pancreatic carcinoma and chronic pancreatitis was not possible in 3 (6.5%) out of 46 cases. High quality 3D-MR angiograms were obtained in 43 (93.5%) cases. In 6 (13%) patients 3D-MRA showed an aberrant right hepatic artery. The overall accuracy of MRI in assessing extrapancreatic tumor spread, lymph node metastases, liver metastases, and vascular involvement was 95.7%, 80.4%, 93.5%, and 89.1%, respectively. CONCLUSION: Due to its high accuracy, the "all-in-one" MR protocol may become the most important modality after clinical examination and ultrasound in the diagnostic work-up for most patients with suspicion of pancreatic tumors.

Arteries↗
PubMed1999

MR imaging of pancreatic lesions. Comparison of manganese-DPDP and gadolinium chelate.

RATIONALE AND OBJECTIVES: To compare manganese-DPDP-enhanced and gadolinium-DTPA-enhanced MR imaging in patients suspected of having pancreatic cancer. METHODS: Fifteen patients who underwent MR imaging for suspected pancreatic cancer and received gadolinium-DTPA took part in a clinical phase III trial in which the efficacy of manganese-DPDP for detection of pancreatic cancer was evaluated. T1-weighted gradient-echo (GRE) images with and without fat suppression were used. Signal-to-noise ratio and contrast-to-noise ratio were calculated before and after the administration of each contrast agent. Image quality was assessed using a four-step score; delineation of the normal pancreas was assessed by two readers in consensus. RESULTS: In terms of pancreatic signal-to-noise ratio, only gadolinium-DTPA-enhanced fat-suppressed and non-fat-suppressed GRE imaging showed a significant (P < 0.001) increase (72% and 61%, respectively). In the patients with a focal pancreatic lesion (n = 14), a significant increase in contrast-to-noise ratio was found only in manganese-DPDP-enhanced GRE imaging without (106%) and with (82%) fat saturation. Qualitative image analysis demonstrated a significant improvement of manganese-DPDP-enhanced fat-suppressed MR images in delineating the pancreatic parenchyma (P < 0.01) as well as pancreatic tumors (P < 0.01). CONCLUSIONS: T1-weighted manganese-DPDP-enhanced GRE imaging with fat saturation should be regarded as the most suitable combination for detecting a pancreatic lesion.

Adult↗
PubMed1999

Breath-hold MR cholangiopancreatography with three-dimensional, segmented, echo-planar imaging and volume rendering.

End-expiration, 21-second breath-hold, three-dimensional magnetic resonance (MR) cholangiopancreatography (MRCP) was developed with segmented echo-planar imaging. In 15 healthy subjects and 14 randomly selected patients undergoing liver studies, three-dimensional MRCP images were obtained and volume rendered. In 15 (100%) healthy subjects and 13 (93%) patients, clear depiction of biliary, hepatic, and pancreatic ducts (with lumen diameter of at least 2 mm) was possible with good signal-to-noise ratio.

Adult↗
PubMed1999

Lack of evidence of acute ischemic tissue change in transient global amnesia on single-shot echo-planar diffusion-weighted MRI.

BACKGROUND AND PURPOSE: There is uncertainty concerning the etiology of transient global amnesia (TGA). Previous CT and MRI studies have indicated that permanent structural abnormality is rare in TGA. Diffusion-weighted (DW) MRI is very sensitive to early ischemic parenchymal changes and has recently demonstrated embolic infarction in the posterior cerebral artery territory in 2 TGA patients. We report the findings of DW MRI in 8 patients in acute stages of TGA. METHODS: Conventional and echo-planar DW MRI was performed in 2 patients in the active phase and 6 patients in the recovery phase (1 to 8 hours after cessation of anterograde memory dysfunction) of spontaneously occurring TGA. RESULTS: None of the patients showed signs of hyperintensity on DW images or hypointensity on quantitative apparent diffusion coefficient (ADC) maps to suggest regional decreases of water mobility or acute T2 changes on transverse or coronal slices. CONCLUSIONS: We were unable to detect ADC or acute T2 changes with echo-planar DW MRI in patients with TGA, which suggests that mechanisms other than ischemic infarction may cause TGA. We did not identify spreading depression-associated changes of the ADC. Further refinement of MRI sequences may be necessary to detect subtle or transient signal change in brain parenchyma.

Aged↗
PubMed1999

[Lymph node imaging with ultra-rapid 3D MR angiography].

PURPOSE: A report on observations of lymph node images obtained by gadolinium-enhanced 3D MR angiography (MRA). METHODS: Ultrarapid MRA (TR, TE, FA-5 or 6.4 ms, 1.9 or 2.8 ms, 30-40 degrees) with 0.2 mmol/kg BW Gd-DTPA and 20 ml physiological saline. Start after completion of injection. Single series of the pelvis-thigh as well as head-neck regions by use of a phased array coil with a 1.5 T Magnetom Vision or a 1.0 T Magnetom Harmony (Siemens, Erlangen). We report on lymph node imaging in 4 patients, 2 of whom exhibited benign changes and 2 further metastases. In 1 patient with extensive lymph node metastases of a malignant melanoma, color-Doppler sonography as color-flow angiography (CFA) was used as a comparative method. RESULTS: Lymph node imaging by contrast medium-enhanced ultrarapid 3D MRA apparently resulted from their vessels. Thus, arterially-supplied metastases and inflammatory enlarged lymph nodes were well visualized while those with a.v. shunts or poor vascular supply in tumor necroses were poorly imaged. CONCLUSIONS: Further investigations are required with regard to the visualization of lymph nodes in other parts of the body as well as a possible differentiation between benign and malignant lesions.

Adult↗
PubMed1998

Non-invasive imaging of abdominal vascular pathologies.

With the advent of ultrasound (US), Doppler and color-flow Doppler imaging, computed tomography (CT), and magnetic resonance angiography (MRA) the ability for non-invasive studies of the abdominal vasculature has been enhanced considerably. In this paper an overview on various abdominal vascular pathologies is presented. Because of the dramatic improvements in image quality, special emphasis is given on the potential role of breathhold contrast-enhanced three-dimensional (3D) MRA which appears to be a versatile non-invasive alternative to conventional angiography.

Abdomen↗
PubMed1998

[First clinical results of ultrafast, contrast-enhanced 2-phase 3D-angiography of the abdomen].

PURPOSE: To assess the utility of breath-hold abdominal ultrafast three-dimensional (3D) gadolinium-enhanced dual-phase magnetic resonance angiography (MRA). MATERIAL AND METHODS: 125 patients with various abdominal pathologies were imaged using a breath-hold ultrafast gadolinium-enhanced dual-phase 3D-MRA technique. RESULTS: 119 (95%) of 125 MRA's were of good or excellent quality. The sensitivity in the detection of renal artery stenoses as well as stenoses of the celiac trunk and the superior mesenteric artery was 100%. Accessory renal arteries (n = 9) and replaced hepatic arteries (n = 4) were reliably detected by MRA. In 24 (71%) of 34 cases MR-angiographic delineation of the spleno-portal system and hepatic veins was superior compared to conventional angiography. CONCLUSION: Breath-hold gadolinium-enhanced dual-phase 3D-MRA has the potential to replace conventional angiography in the abdomen.

Abdomen↗