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G Staatz

Publications and source records attributed to G Staatz.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Panorama ultrasonography of the abdominal wall for delineation of the anatomy and diagnosis of pathological findings].

PURPOSE: To assess extended field-of-view sonography for delineation of the anatomic structures of the abdominal wall and for the diagnosis of hernia. MATERIAL AND METHODS: In 34 cases (24 probands, 10 patients with abdominal wall defects) extended field-of-view sonography of the abdominal wall was performed with a 7.5 MHz transducer. Dynamic alignment of real-time images allows for depiction of regions of up to 60 cm in a single extended field-of-view image. A standardized axial image was obtained above and below the arcuate line and at the level of the defect, respectively. All images were evaluated by two blinded readers regarding the visibility of the anatomic structures and the delineation and extent of pathological changes. RESULTS: The abdominal wall was delineated with extended field-of-view sonography in all patients with a good image quality. The linea alba, the rectus muscle and the three lateral abdominal muscles, the rectus sheath, the peritoneum, and the subcutaneous fatty tissue were visible. In the patients with abdominal wall defects, the hernial sac with its contents, the extension of the defect, and the surrounding structures were clearly delineated. CONCLUSION: Extended field-of-view sonography allows for easily surveyed and reproducible documentation of the ultrasound examination of the abdominal wall. It is especially useful for the preoperative planning in patients with abdominal wall defects.

Abdominal Muscles↗
PubMed2001

[Gadolinium-enhanced T(1)-weighted MR urography versus T(2)-weighted (HASTE) MR urography in children].

PURPOSE: To evaluate gadolinium-enhanced T(1)-weighted excretory MR urography (EMRU) versus T(2)-weighted (HASTE) MR urography in children with upper urinary tract abnormalities. PATIENTS AND METHODS: In a prospective study 63 children, aged from 3 weeks to 15 years, underwent MR urography in a 1.5-T scanner. Before and after an intravenous injection of 0.05 mg/kg body weight of furosemide, respiratory-triggered HASTE images were obtained for T(2)-weighted MR urography. EMRU was performed subsequent to i. v. gadolinium injection with respiratory-gated, coronal 3 D-gradient-echo sequences. RESULTS: Compared to T(2)-weighted (HASTE) MR urography, gadolinium-enhanced MR urography revealed a superior diagnostic accuracy in non-dilated collecting systems (horseshoe kidneys, ectopic kidneys, duplex systems, single ectopic ureters, ureteroceles). EMRU and T(2)-weighted (HASTE) MRU turned out to be equivalent in the assessment of obstructed but normal functioning upper urinary tracts (UPJ obstructions, megaureters). Non-functioning dilated collecting systems and multicystic dysplastic kidneys were best visualized with use of T(2)-weighted (HASTE) MR urography. CONCLUSION: Respiratory-gated gadolinium-enhanced T(1)-weighted MRU allows accurate evaluation of most upper urinary tract abnormalities. T(2)-weighted (HASTE) MRU complements GMRU in the evaluation of non-functioning renal units and cystic disease of the kidneys.

Adolescent↗
PubMed2001

[Interstitial T1-weighted MR lymphography with use of the dendritic contrast agent Gadomer-17 in pigs].

PURPOSE: To investigate the enhancement of regional lymph nodes, lymph vessels and the thoracic duct after subcutaneous administration of the dendritic contrast agent Gadomer-17. MATERIALS AND METHODS: Interstitial T(1)-weighted MR lymphography was performed in 15 domestic pigs in a 1.5 T MR scanner using the body coil. The contrast agent was injected subcutaneously at a dose of 2.5, 10 and 20 micromol gadolinium/kg/bw (1.4 - 2.3 ml) in the hind legs of 5 pigs, respectively. T(1)-weighted coronal 3D-gradient-echo images were obtained 1 to 150 minutes and 24 hours after contrast material injection. RESULTS: Inguinal lymph nodes, iliac lymph nodes and lymph vessels showed peak enhancement within 10 minutes after subcutaneous administration of the contrast agent. The enhancement of the lymphatic system decreased slowly until 150 minutes post injection. The time-response study, which was performed for inguinal and iliac lymph nodes, revealed the best lymphographic effect for Gadomer-17 at a dose of 10 micromol gadolinium/kg/bw. At this dose the paraaortic lymph nodes and the thoracic duct were also best visualized. CONCLUSION: Interstitial administration of the evaluated dendritic contrast agent Gadomer-17 is highly efficient for the performance of T(1)-weighted MR lymphography in regional lymph nodes, lymph vessels and the thoracic duct.

Animals↗
PubMed2001

Interstitial T1-weighted MR lymphography: lipophilic perfluorinated gadolinium chelates in pigs.

PURPOSE: To investigate the enhancement of the regional lymph nodes, lymphatic vessels, and thoracic duct after interstitial administration of lymphotropic perfluorinated gadolinium chelates at magnetic resonance (MR) imaging. MATERIALS AND METHODS: Two perfluorinated gadolinium chelates, gadofluoramide and gadofluorine 8, were injected subcutaneously into the hind legs of 10 pigs, respectively. Both contrast media were studied at doses of 10 and 25 micromol per kilogram of body weight. T1-weighted three-dimensional gradient-echo and maximum intensity projection images were obtained at 1.5 T between 1 and 210 minutes and 24 hours after injection. The contrast agents were qualitatively compared regarding enhancement and depiction of the regional lymph nodes, lymphatic vessels, and thoracic duct. RESULTS: The inguinal and iliac lymph nodes and lymphatic vasculature enhanced substantially within 10 minutes after subcutaneous administration of both lymphotropic contrast agents. Gadofluorine 8 showed a lymphographic effect superior to that of gadofluoramide. The paraaortic lymph nodes and thoracic duct were best visualized 10--50 minutes after injection of 25 micromol/kg of gadofluorine 8. Lymphatic system enhancement diminished after 2 hours, and the liver and bowel tract enhanced within 24 hours. CONCLUSION: Interstitial administration of perfluorinated gadolinium chelates offers great potential for T1-weighted MR lymphography with positive enhancement of the lymph nodes and lymphatic vasculature.

Animals↗
PubMed2001

Congenital pseudarthrosis of the tibia in pediatric patients: MR imaging.

OBJECTIVE: The purpose of this study was to describe the characteristics of congenital pseudarthrosis of the tibia on MR images of infants and children and to assess the value of MR imaging in evaluating this disease. CONCLUSION: MR imaging of congenital pseudarthrosis allows assessment of the type and extension of the disease. It is especially recommended for the evaluation of periosteal and soft-tissue changes near the pseudarthrosis.

Child, Preschool↗
PubMed2000

Feasibility and utility of respiratory-gated, gadolinium-enhanced T1-weighted magnetic resonance urography in children.

RATIONALE AND OBJECTIVES: To evaluate the feasibility and utility of respiratory-gated, gadolinium-enhanced T1-weighted magnetic resonance (MR) urography in children. METHODS: In a prospective study, 30 consecutive children, aged 3 weeks to 13.8 years, underwent MR urography. After intravenous injection of low-dose furosemide and gadopentetate dimeglumine, respiratory-gated, coronal, T1-weighted 3D-gradient-echo sequences were obtained at 1.5 T 5 to 30 minutes after contrast administration. Postprocessing of the data was performed using a maximum-intensity projection algorithm. In addition, precontrast half-Fourier rapid acquisition with relaxation enhancement MR urograms were obtained in 29 children. RESULTS: Respiratory-gated, T1-weighted MR urography was successfully performed in all children without the need for sedation. Compared with the final diagnosis, prospective analysis of MR urography images revealed the correct diagnosis in 56 of 58 pelvicaliceal systems (96%). The ureteral morphology was correctly evaluated in 59 of 64 ureters (92%). The method showed limited efficiency for evaluating nonfunctioning renal units. CONCLUSIONS: Respiratory-gated, gadolinium-enhanced T1-weighted MR urography is a feasible and effective diagnostic tool in the assessment of upper urinary tract morphology in children. It is especially useful in depicting nondilated collecting systems and ureters.

Adolescent↗
PubMed1999

[CT-guided percutaneous biopsies for the classification of focal liver lesions: a comparison between 14 G and 18 G puncture biopsy needles].

PURPOSE: Analysis and comparison of CT-guided 14- and 18-gauge cutting needle biopsies to accurately assess focal liver disease. METHODS: The data of 272 CT-guided biopsies in 268 patients were evaluated retrospectively with regard to sensitivity, specificity and complication rate of the chosen needle caliber in differentiating between benign and malignant disease as well as in the ability to determine specific cell types in the various disorders. A 14-gauge (G) needle was used in 101 (37.1%) cases, an 18-g needle biopsy was performed in 171 (62.9%) cases. The Fisher exact test was employed for statistical analysis. RESULTS: Cutting needle biopsy yielded sufficient histologic material in 267 of 272 (98.2%) cases. Correct diagnosis of malignancy was established in 178 of 191 (93.2%) lesions, 73 of 76 (96.1%) disorders were accurately defined as benign, resulting in an overall value of 94.0% (251 of 267). Of these 251 biopsies a definite histological diagnosis could be determined in 90.6% of the cases employing a 14 G needle and in 90.3% using an 18-g needle. The sensitivity, specificity and rate of complications were 94.8%, 92.0%, 3.0% for the 14-g needle and 92.7%, 97.6%, 0.6% for the 18-g needle, respectively. There were no statistically significant differences with regard to the needle size. CONCLUSIONS: CT-guided biopsy of hepatic lesions with the 18-g biopsy needle is of equivalent diagnostic accuracy when compared with the 14-g needle.

Adult↗
PubMed1999

[Virtual endoscopy of the upper urinary tract based on contrast-enhanced MR urography data sets].

PURPOSE: To investigate the feasibility of reconstructing a virtual endoscopy from MR imaging data sets of the upper urinary tract. METHOD: The data obtained from 28 contrast-enhanced MR urographic examinations (5 normal; 23 pathologic) were post-processed to reconstruct a virtual ureterorenoscopy (VURS) using a threshold image segmentation. The visualization of the upper urinary tract was based on the acquisition of T1-weighted 3D gradient-echo sequences after intravenous administration of gadolinium-DTPA and a prior injection of low-dose furosemide. RESULTS: The employed MR urography technique created in all 28 cases a complete and strong contrast enhancement of the urinary tract. These 3D sequence data allowed the reconstruction of a VURS, even when the collecting system was not dilated. The best accuracy was provided by the MR urography sequences with the smallest voxel size. Moreover, the data acquisition based on a breath-hold technique has proved superior to that using a respiratory gating. Inside the renal pelvis, all calices could be assessed by turning the virtual endoscope in the appropriate direction. The visualization of the ureteral orifices in the bladder was also possible. All filling defects that were diagnosed by MR urography could be evaluated from the endoluminal view using the VURS. The exact characterization of the lesions based only on the assessment of the surface structure was difficult. CONCLUSION: A virtual endoscopy of the upper urinary tract can be successfully reconstructed using the data sets of high-resolution 3D MR urography sequences.

Adult↗
PubMed1999

[Panorama ultrasound of the spinal canal with determination of the level of the conus medullaris in newborn infants and infants].

PURPOSE: To evaluate the utility of panoramic ultrasound in visualizing the spinal canal and the conus medullaris level in neonates and young infants. METHOD: 30 children (aged 2 days to 5 months, 2058-6660 g, 41-57 cm) underwent examination of the spinal canal. The children were examined by a single, continuous 9.0 MHz transducer movement from the cervico thoracic spine to the coccyx. A dedicated computer processor produced an extended field of view image in realtime mode. RESULTS: With panoramic ultrasound coverage of the thoracic, lumbar and sacral spinal canal on one extended image was possible. Visualization of the spinal cord, the conus medullaris level, the subarachnoid space, the cauda equina and the tip of the dural sac was easily accomplished in each child. An average of four trials was necessary to obtain an image of sufficient diagnostic quality. The conus level ranged from L1 to L3, the tip of the dural sac was localized at S1 to S3. CONCLUSIONS: Panoramic ultrasound offers nearly complete visualization of the spinal canal in children on one single extended field of view image. The conus medullaris level and the tip of the dural sac can easily be localized.

Cauda Equina↗
PubMed1998

Spondylodiskitic abscesses: CT-guided percutaneous catheter drainage.

PURPOSE: To determine whether computed tomographically (CT) guided percutaneous catheter drainage of spondylodiskitic abscesses is an appropriate and effective alternative to surgery. MATERIALS AND METHODS: CT-guided percutaneous catheter drainage was performed in 21 patients (16 men, five women; age range, 24-81 years) with 33 spondylodiskitic abscesses. Nine intradiskal, 12 paravertebral, and 12 psoas abscesses were drained with 5.6-14.0-F catheters. In 29 cases, the catheter was inserted by using the Seldinger technique in four cases, a trocar technique was used. All patients underwent follow-up CT or magnetic resonance imaging examinations for 6 months. RESULTS: Successful placement of the drainage catheter was achieved in each patient without procedural complications. The duration of drainage was 4-56 days (average duration, 26.8 days). Three of 33 catheters were changed because of insufficient drainage; one of the 33 catheters had to be reinserted because of dislocation. Two patients underwent surgery for stabilization of the spine with the drainage catheter in place. In 16 of the 21 patients, specific organisms were isolated; thus, definitive medical therapy was possible. Complete evacuation of all abscesses was achieved initially, with no evidence of recurrence during the follow-up. CONCLUSION: CT-guided percutaneous catheter drainage is an efficient and safe procedure in the management of spondylodiskitic abscesses.

Abscess↗
PubMed1997

[Osteoporotic stress fractures of the sacrum: MR-tomography findings].

PURPOSE: Evaluation of the morphologic appearance of sacral osteoporotic insufficiency fractures in MRI. PATIENTS AND METHOD: 6 patients (5 female and one male, 54-80 years) with osteoporotic insufficiency fractures of the sacrum were examined with CT and MRI. Plain and contrast-enhanced T1- and T2-weighted spin-echo images were acquired, three patients were studied with T1-weighted gradient-echo-sequences with fat suppression. RESULTS: Fracture-lines and sclerotic areas of the massae laterales were visible in 5 of 6 CT examinations, one patient showed no abnormalities of the sacrum on the initially performed CT scans. All patients had a diffuse bone marrow oedema of the fractured massae laterales with a decreased signal on the T1-weighted spin-echo images and an increased signal on the T1-weighted gradient-echo images with fat suppression and in the T2-weighted SE-sequences. Gadopentate dimeglumine enhanced MRI images showed a remarkable diffuse configurated high signal of the whole sacrum in bilateral fractures (H-pattern). An additional soft tissue mass could be excluded in each case. CONCLUSION: Gadopentate dimeglumine enhanced MRI of sacral insufficiency fractures allows early diagnosis and helps to exclude intraosseous tumour formation.

Aged↗
PubMed1993

[Pneumatosis cystoides intestinii].

Pneumatosis cystoides intestinalis (PCI), a condition involving submucosal or subserosal gas-containing cysts of the wall of the gastrointestinal tract, is a rare entity. It is mostly diagnosed between the third and fifth decades of life without a clear sexual predominance. Different aetiopathogenetic factors are under discussion, the most probable being a bacteriologic cause (Clostridium perfringens) in combination with minimal leaks in the mucosal barrier. There are no pathognomonic symptoms; the clinical picture ranges from incidental findings to haematochezia. Diagnosis is based on plain abdominal film and X-ray following barium enema. Methods of treatment in symptomatic cases are oxygen and antibiotic (metronidazole) therapies and, in severe cases, resection of the diseased part of the intestine.

Colectomy↗
PubMedDate not supplied

MR urography today.

Magnetic resonance (MR) urography is performed by pursuing two different imaging strategies. On the one hand, heavily T2-weighted turbo spin-echo sequences are employed for obtaining unenhanced static-water images of the urinary tract. On the other, the T(1)-weighted MR urographic technique imitates conventional intravenous pyelography and is, therefore, referred to as excretory MR urography. For this reason, a gadolinium contrast agent is injected intravenously and, after its renal excretion, the gadolinium-enhanced urine is imaged with fast T1-weighted gradient-echo sequences. Both MR urographic techniques can be combined for a comprehensive examination of the upper urinary tract. This article reviews the current technical principles, imaging capabilities, and clinical applications of T2- and T1-weighted MR urography in adult and pediatric patients.

Adult↗
PubMedDate not supplied

[Treatment of osteoid osteoma: percutaneous procedure in comparison with open surgery].

AIM: In recent years osteoid osteomas have been treated more frequently by means of percutaneous procedures. Several percutaneous techniques have been established. Our study presents the results which were obtained using a percutaneous drill system. In addition, a comparison between the results of the percutaneous procedure and the open surgical therapy is performed. METHOD: The retrospective study included patients with an osteoid osteoma who underwent percutaneous therapy or open surgery between 1992 and 2000. The following variables were addressed: age, gender, duration of complaints, localisation of the tumour, duration of hospital stay, size of the nidus, histology and recurrences. RESULTS: Of the total of 22 patients with an osteoid osteoma, 10 (45 %) were treated percutaneously and 12 (55 %) surgically. With regard to age, gender, and duration of complaints, the two groups were similar. Six (60 %) of the percutaneously treated patients sustained at least one recurrence. On the other hand, only one patient (8 %) of the surgically treated group experienced a recurrence. CONCLUSIONS: In comparison with recent studies presenting success rates in percutaneous treatment of osteoid osteomas between 77 and 100 percent, our own results are worse. One explanation for the low success rate might be the small drill size used.

Adolescent↗