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W Rohrschneider

Publications and source records attributed to W Rohrschneider.

At least 19 recordsLinked to original sources
PubMed2004

[Rhabdoid tumors of the kidney in childhood].

PURPOSE: The primary diagnosis of renal masses in children is made by imaging studies. This retrospective analysis describes the imaging features of rhabdoid tumors (RT) with US, CT and MRI, to point out characteristics and to evaluate the possibility of differentiation between RT and Wilms tumor. MATERIALS AND METHODS: We reviewed 10 MRI (6 STIR, 9 T1 w, 8 T2 w, 10 T1 post KM), 15 CT (9 Nativ-CT, 14 KM-CT) and 14 US images of 22 patients (age 2 - 57 months) with histopathologically confirmed RT. The following characteristics were evaluated: subcapsular fluid collection, multiple tumor lobules, presence of calcification, primary tumor size, visibility of tumor margin, tumor necrosis and metastases. RESULTS: The mean total tumor volume was 238 ml. 19 RT were located in the perihilar/medullary region with invasion of the renal hilum, and 5/22 tumors showed multiple tumor lobules. Subcapsular fluid collection was found in 6/22 cases. Calcifications were present in 6/19. Eleven tumors were well defined from the renal parenchyma, 9 poorly defined, 2 could not be assessed. In 19/22 cases tumor necrosis was found. Distant metastases were seen in 8 cases in the lung, in 3 cases in the CNS. Metastases of regional lymph nodes were seen in 9 cases. CONCLUSION: The evaluated characteristics frequently found in RT are not indicative of these tumors. RT cannot clearly be differentiated from Wilms tumor by imaging studies. Because of frequent involvement of the CNS and lung, a MRI of the CNS and CT of the lung is indicated after histopathologic diagnosis of RT is made.

Child, Preschool↗
PubMed2002

German pediatric reference data for quantitative transverse transmission ultrasound of finger phalanges.

Quantitative ultrasound (QUS) of the finger phalanges is a useful tool in the assessment of disease- or age-related deterioration of bone. For studying the impact of juvenile diseases or growth disorders affecting the skeleton, a reference database for QUS parameters is needed. The aim of this study was to establish a calibrated reference database of parameters of transverse ultrasound transmission through juvenile finger phalanges. A total of 1328 children (650 females, 678 males; ages 3-17 years) were measured in Heidelberg and Kiel in order to establish a German reference database. Highly significant gender-specific correlations (p<0.0001) were found between the QUS parameters amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) versus age, body height and body mass index (BMI). For AD-SoS the correlation coefficients were R2 = 0.64 against age in males and R2 = 0.73 in females, R2 = 0.60 against body height in males and R2 = 0.68 in females, and R2 = 0.19 against BMI in males and R2 = 0.23 in females. For BTT the correlation coefficients were R2 = 0.74 against age in males and R2 = 0.79 in females, R2 = 0.75 against body height in males and R2 = 0.77 in females, and R2 = 0.32 against BMI in males and R2 = 0.35 in females. Age and height were the strongest determinants of QUS results. Gender-specific differences were observed in AD-SoS (significant for ages 11-14 years and for 150-170 cm body height) and in BTT (significant for ages 7 and 11-17 years and for 160-170 cm body height). Tables of QUS parameters versus age and height can serve as a basis for the evaluation of the impact of skeletal diseases or growth disorders on phalangeal QUS. Depending on the type of disease or growth disorder, measurement results can be compared with age- or height- specific reference data. In this way a simple and radiation-free assessment of juvenile skeletal disorders using quantitative ultrasound might be possible in the future.

Adolescent↗
PubMed2001

[Acute hematogenous osteomyelitis--exclusion with Turbo-STIR sequence?].

The timely diagnosis and early initiation of antibiotic therapy determine the clinical course of an acute hematogenous osteomyelitis. Consequently, a fast and efficient MRI examination protocol is crucial. We retrospectively evaluated various MR sequences used in the examination of 8 children having osteomyelitis. The examinations were conducted using a 0.5 T MR machine. All patients had a high signal intensity of the lesion in the IR sequence with fat suppression (turbo-STIR). An acute osteomyelitis can be excluded in the absence of signal intensity increase in the turbo-STIR sequence without the necessity of having to perform additional sequences.

Acute Disease↗
PubMed2001

Reduction in voiding cystourethrographies after the introduction of contrast enhanced sonographic reflux diagnosis.

BACKGROUND: Voiding urosonography (VUS) using the intravesical application of an US contrast medium (Levovist) has been shown to have very high sensitivity and specificity in the diagnosis of vesicoureteric reflux (VUR) compared to voiding cystourethrography (VCUG). OBJECTIVE: To determine the extent of reduction of VCUGs after adding VUS to the diagnostic algorithm of VUR. MATERIALS AND METHODS: Over 2 years, 449 children (162 boys, 287 girls) were referred for diagnosis of possible VUR. The selection of a particular reflux examination was based on pre-defined criteria. VUS was performed primarily in girls and follow-up cases. The indications for VCUG were as follows: (a) boys - first examination for VUR, (b) specific request for urethra or bladder imaging, (c) girls - when VUR was diagnosed in the VUS and no VCUG had been done previously, and (d) inadequate VUS. RESULTS: VCUGs were primarily carried out in 141 cases. VUSs were performed in 308 patients. In 69 of these patients a VCUG followed during the same examination session. Thus 239 of 449 patients underwent only VUS, resulting in reduction of the VCUGs by 53 %. CONCLUSIONS: The number of VCUGs was significantly reduced as a result of the implementation of VUS as part of the routine diagnostic imaging modality for VUR. Consequently, the number of children that would have been exposed to ionising radiation was reduced by over half.

Adolescent↗
PubMed2001

Internal jugular venous valves in children: high-resolution US findings.

The aim of this study was to determine in children the prevalence rate and to describe the sonographic morphology of the valves in the internal jugular veins. One hundred twenty children (60 boys and 60 girls; mean age +/- SD 10 +/- 4 years, age range 3-20 years) were recruited for the study. They underwent sonographic examination of both internal jugular veins. The number of valvular cusps, the length of the cusps and exact site of origin were recorded. In 96% of the children a valve was found in one or both internal jugular veins. Within this group a valve was detected unilaterally in 26% and bilaterally in 74% of the cases. Ultrasound morphological and morphometric analysis was carried out in a total of 239 internal jugular veins; 200 (84%) veins were found to have valves. The origin of the cusps was located at a mean distance of 9 mm (0-26 mm) proximal to the confluence of the subclavian and internal jugular veins into the brachiocephalic vein. A valve in the distal part of the internal jugular vein is a very common finding with characteristic features on US.

Adolescent↗
PubMed2001

Contrast-enhanced harmonic imaging for the diagnosis of vesicoureteral reflux in pediatric patients.

OBJECTIVE: Harmonic imaging using phase or pulse inversion technology is a new sonographic diagnostic modality that has the potential to produce images of a higher quality than can be obtained with the conventional method. The aim of this study was to compare both types of harmonic modalities--tissue and contrast harmonic imaging--with the fundamental imaging mode in contrast-enhanced B-mode sonographic diagnosis of vesicoureteral reflux. SUBJECTS AND METHODS: Fifty-four children presenting for diagnostic examination of vesicoureteral reflux underwent standard sonography of the urinary tract in the fundamental mode, followed by intravesical administration of a galactose-based contrast medium containing microbubbles. The contrast-enhanced sonography was conducted by scanning the bladder and each kidney in transverse and longitudinal planes, from ventral and dorsal views, consecutively in B-mode using fundamental, contrast harmonic, and tissue harmonic imaging modalities. Soft-touch buttons on the console screen were used to alternate between the three imaging options, so that switching from one modality to the other could be done almost instantaneously. For comparison, in each patient, we selected one set of contrast-enhanced images of the bladder and two sets, one ventral and one dorsal, of the kidney. In a series, the images were compared and ranked from 1 to 3, with 1 being the best, with regard to sonomorphology (demarcation of the retrovesical space and renal pelvis as the potential sites to look for vesicoureteral reflux) and reflux detection and conspicuity, if present. RESULTS: In all, 248 sets of images were available for comparison. The delineation of both the retrovesical space and the renal pelvis was found to be best with tissue harmonic imaging in 84% and 96% of the image sets, respectively (p < 0.01). Forty-one sets of images were compared from 27 kidney-ureter image units of 22 children (41%) with reflux. The refluxing microbubbles were much more conspicuous in the harmonic imaging mode (tissue harmonic, 100%; contrast harmonic, 93%) than in the fundamental mode (p < 0.01). In eight kidney-ureter units, the reflux was detected only by using the harmonic imaging modalities. CONCLUSION: Visualization of the urinary tract and detection of ultrasound contrast media is significantly improved by the use of the harmonic imaging modalities. When both fundamental and harmonic imaging options are available, we recommend harmonic imaging for contrast-enhanced sonographic diagnosis of vesicoureteral reflux.

Adolescent↗
PubMed2000

A case of Perlman syndrome: fetal gigantism, renal dysplasia, and severe neurological deficits.

We report on a neonate presenting with polyhydramnios; macrosomia; macrocephaly; visceromegaly including bilateral nephromegaly, hepatomegaly, cardiomegaly; thymus hyperplasia; cryptorchidism; generalized muscle hypotonia; and a distinctive facial appearance. The clinical course was marked by severe neurodevelopmental deficits combined with progressive respiratory decompensation leading to death at the age 6 months. Magnetic resonance imaging (MRI) disclosed a generalized cerebral atrophy with a marked deficit of the white matter. Renal ultrasound and MRI showed markedly enlarged kidneys with multiple small cystic lesions, a pattern indistinguishable from polycystic kidney disease. The postmortem kidney biopsy revealed dysplastic changes, microcysts, and a focal nephrogenic rest, characteristic features of the Perlman syndrome. In children with fetal gigantism, renal abnormalities, and neurological deficits, Perlman syndrome should be considered and may be confirmed by kidney biopsy.

Abnormalities, Multiple↗
PubMed1999

[Diagnostic imaging of the kidneys and the urinary tract in children].

Imaging flow charts differ in pediatric and general radiology. The reasons are: different illnesses, different consequences arising out of imaging results and different sequence of imaging methods. Ultrasound is always the first imaging method of the urinary tract in infancy and childhood starts with ultrasound with the exception of severe abdominal trauma which is investigated by computer-tomography. The decision "normal or abnormal" is possible using ultrasound in the most pediatric cases. The diagnostic value and significance of ultrasound in infancy and childhood is far better than in general radiology because of the higher resolution of the high-frequency units taken. The result of the ultrasound examination should be the basis for the following imaging procedures. We will describe diagnostic flow charts starting with three important clinical symptoms: Prenatal pathology, urinary tract obstruction and urinary tract infection.

Age Factors↗
PubMed1999

Reflux in young patients: comparison of voiding US of the bladder and retrovesical space with echo enhancement versus voiding cystourethrography for diagnosis.

PURPOSE: To compare the usefulness of voiding US of the bladder and retrovesical space with echo enhancement with that of voiding cystourethrography (VCUG) for diagnosis of vesicoureteral reflux (VUR) and to assess patient tolerance of the echo-enhancing agent. MATERIALS AND METHODS: One hundred eighty-eight patients (aged 5 days to 20 years) referred for investigation of VUR underwent voiding US with echo enhancement, which was followed by VCUG in 110 patients (226 kidney-ureter units). After US of the renal tract, the bladder was filled with normal saline solution. Then SU U 508 A, a galactose-based, microbubble-containing echo-enhancing agent, was administered. Reflux was diagnosed when microbubbles appeared in the ureter or pelvicalyceal system. RESULTS: VUR was detected in 80 of the units with one (n = 18) or both (n = 62) methods. All grades of reflux were identified. In 15 units, reflux diagnosed at voiding US was not observed at VCUG; the reverse was true in three units. In 208 (92%) of the 226 kidney-ureter units, there was concordance between the two methods regarding the diagnosis or exclusion of VUR. The echo-enhancing agent was well tolerated. CONCLUSION: SH U 508 A enhanced voiding US is as good as VCUG in the detection or exclusion of VUR and thus will make it possible to reduce the number of children having to be exposed to ionizing radiation.

Adolescent↗
PubMed1998

[Diagnosis of vesicoureteral reflux with echo-enhanced micturition urosonography].

AIM: To ascertain the diagnostic efficacy of reflux sonography with the application of the echo-enhancing agent Levovist in comparison with X-ray voiding cystourethrography (VCUG). PATIENTS AND METHODS: Echo-enhanced voiding urosonography (VUS) and VCUG were performed successively in one examination session in 114 children referred for the investigation of possible vesicoureteral reflux (VUR). After sonography of the urinary tract the bladder was filled with normal saline and Levovist was administered. Reflux was diagnosed when hyperechogenic, floating microbubbles appeared in the ureters or renal pelvises. RESULTS: A total of 226 kidney-ureter units were available for analysis. Reflux was diagnosed in 80 units. All grades of reflux were represented. In 15 kidney-ureter units VUR was diagnosed with echo-enhanced VUS but was not seen at VCUG. The contrary was true in 3 units. High sensitivity and specificity in comparison to the VCUG could be attributed to the echo-enhanced VUS. The long imaging window attainable with Levovist makes the documentation of convincing images possible, contributing to the high diagnostic efficacy. CONCLUSION: Echo-enhanced VUS is comparable to VCUG in the diagnosis of reflux.

Adolescent↗
PubMed1997

[Invagination].

Intussusception is the most common abdominal emergency in infancy and childhood. Most cases are idiopathic ileocolic intussusceptions; rarely is a lead point present. Abdominal ultrasound is the imaging modality of choice for the demonstration as well as the exclusion of an intussusception. The target (transverse section) and pseudokidney (longitudinal section) signs are pathognomonic sonographic findings. Simultaneous depiction of lead points or lymph nodes or the presence of an entero-enteral intussusception may lead to different appearances. When an intussusception has been diagnosed with ultrasound, further complications such as small bowel obstruction or free intraperitoneal fluid have to be excluded at the same time. In addition, the perfusion of the intussusceptum can be evaluated with color Doppler ultrasound. There is general consensus that the only contraindications for conservative reduction are bowel perforation, peritonitis and hypovolemic shock. The oldest and most widespread method is hydrostatic reduction with barium under fluoroscopic control. Pneumatic reduction under fluoroscopic monitoring has gained more and more acceptance. An alternative technique is sonographically guided hydrostatic reduction with normal saline solution. Both latter methods are reported to have success rates of 80-90% and are clearly superior to the barium technique. In our opinion ultrasound monitoring offers the most precise control of the whole reduction process, with distinct demonstration of the intraluminal structures, especially of the ileocecal valve and of a possible lead point. A complication can be recognized immediately. The primary advantage is the lack of radiation exposure. Therefore, with appropriate equipment and experience this method may be regarded as most promising in the management of intussusception in infancy and childhood.

Abdomen, Acute↗
PubMed1996

[Ultrasound of extracerebral spaces in infants: standardized examination technique].

High resolution ultrasound (5/7.5 MHz, linear array) allows imaging of the extracerebral space in infants. A standardised state-of-the-art imaging technique is described that can be performed during routine cranial sonography. Diagnosing dilated subarachnoid space is possible by comparison to normal values. Pathological findings of the subarachnoid and subdural space can be differentiated. Evaluation of the following conditions is possible: external hydrocephalus, cortical atrophy, pyogenic meningitis, subdural hematoma and hygroma. High resolution ultrasound can add helpful information in situations in which magnetic resonance imaging or computed tomography were previously needed. Since it is a noninvasive method, ultrasound is ideal for follow-up studies and hence the method of choice.

Dilatation, Pathologic↗
PubMed1994

The post-reduction donut sign.

A donut-shaped intestinal structure in the lower right abdomen, observed during abdominal ultrasound investigation following nonoperative intussusception reduction, may create a diagnostic problem concerning differentiation from a residual or recurrent intussusception or underlying small bowel disease. In 30 cases of ileocolic intussusception an abdominal ultrasound examination was performed after reduction, the success of which was proven by radiological and clinical criteria. More than half of the examinations showed an aperistaltic "donut" in the ileocecal region which was similar to the target sign commonly seen in intussusception. Differentiation was possible according to the following two criteria: first, the diameter of the donut was smaller than that of the original target sign seen in these patients. Second, the donut consisted of a broad hypoechoic rim and an echogenic center, whereas the target was normally composed of multiple concentric rings. One third of the patients showed localized thickening of the walls of the distal ileal loops which did not cause diagnostic problems. All of the suspicious intestinal structures disappeared within the first 5 days following reduction. It is our opinion that the post-reduction donut correlates with significant edema of the ileocecal valve and does not represent a mechanical lead point or persisting residual intussusception.

Female↗
PubMed1994

[The initial experiences with a new method for treating invagination: sonography-guided hydrostatic reduction].

During the last four months we have been treating all 15 sonographically diagnosed intussusceptions by a new method; this is based on the introduction of a saline enema under sonographic control. In 13 cases the method was successful according to imaging and clinical criteria. In two patients conservative reduction was impossible: in one patient partial resection of the ileum was necessary and in the other there was a recurrence which was reduced at operation. There were no complications. The advantages of the method are reduced radiation exposure, complete evaluation of the course of the procedure with definite criteria for success, the ability to recognise an ileo-ileal invagination and to determine the head of the intussusceptum. We can see no disadvantages compared with conventional methods. We regard this method as optimal in future for the treatment of infantile intussusceptions.

Child, Preschool↗
PubMed1992

[Ureteropelvic stenosis in infancy. The value of diuresis sonography compared with diuresis excretory urography].

Examinations under conditions of diuresis produced by drugs can be useful to differentiate pyelo-ureteric obstruction from a dilated collecting system with normal flow. 22 infants with 42 kidneys showing moderate dilatation of one of both renal collecting systems were examined by sonography and excretory urography under conditions of diuresis and the results were compared. Depending on the radiological appearances and contrast clearance rates, four diagnostic groups could be identified; these also differed significantly on the sonographic examinations. In general, there was good agreement between the two methods. Carefully performed, diuresis sonography will clearly distinguish between urodynamically significant obstruction from a wide but non-obstructive collecting system. The number of radiographic examinations can therefore be reduced in these patients.

Diagnosis, Differential↗