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J-P Schenk

Publications and source records attributed to J-P Schenk.

5 recordsLinked to original sources
PubMed2006

[Testicular torsion: diagnosis, differential diagnosis, and treatment in children].

Acute scrotum represents an emergency situation although testicular torsion is present in less than 20% of the cases. Sonography has meanwhile become the definitive modality for diagnosis. Its increasing use before surgical intervention has led to technical improvements in ultrasound diagnostics and critical assessment of ultrasound criteria to exclude testicular torsion as well as standardization of examination procedures. Central arterial and venous perfusion shown to be bilaterally equal on Doppler sonography is the most important criterion for excluding torsion. This article discusses other criteria such as the "resistance index," comparison of parenchymal structure of both testes, evidence for spermatic cord torsion, or differences between the sides in perfusion of the testicular parenchyma and highlights the difficulties involved in partial and intermittent testicular torsion. Alternative investigative methods and the significance of sonography in the differential diagnosis of other underlying causes are addressed. In summary, the combination of interpreting B-mode imaging, color Doppler, and power Doppler sonography and analyzing Doppler flow curves after clinical examination results in successful and conclusive evaluation of the testes in cases of acute scrotum in boys.

Child↗
PubMed2006

[Reference radiology in nephroblastoma: accuracy and relevance for preoperative chemotherapy].

PURPOSE: A reference radiologic diagnosis was carried out for the purpose of quality control and in order to achieve high diagnostic accuracy in the ongoing trial and study SIOP 2001/GPOH for renal tumors during childhood. The aim of the present study is to evaluate the value of diagnostic imaging and the benefit of reference evaluation at a pediatric radiology center. MATERIALS AND METHODS: In 2004 the imaging studies of 97 patients suspected of having a renal tumor were presented at the beginning of therapy. Diagnostic imaging was compared to the primary imaging results and the histological findings and was analyzed in regard to the therapeutic consequence (primary chemotherapy without prior histology). 77 MRI, 35 CT and 67 ultrasound examinations of 47 girls and 50 boys (mean age 4 years; one day to 15.87 years old) were analyzed. In addition to the histological findings, the reference pathological results were submitted in 86 cases. Results from the primary imaging corresponding to the histology and results from the reference radiology corresponding to the histology were statistically compared in a binomial test. RESULTS: In 76 of the reference-diagnosed Wilms' tumors, 67 were confirmed histologically. In 72 cases preoperative chemotherapy was initiated. In 5 cases neither a Wilms' tumor nor a nephroblastomatosis was found. 16 of 21 cases (76 %) with reference-diagnosed non-Wilms' tumors were selected correctly. The results of the primary imaging corresponded to the histology in 71 cases, and those of the reference radiology in 82 cases. The statistical evaluation showed that the results of the reference radiology were significantly better (p = 0.03971). CONCLUSION: Reference radiological evaluation improved the diagnostic accuracy with therapeutic relevance. The differentiation of different renal tumors is not completely possible using imaging methods. The rate of patients with false preoperative chemotherapy for all renal neoplasms is currently 5.2 % and 1 % for benign renal tumors.

Antineoplastic Agents↗
PubMed2005

[Functional and morphological MR imaging of the upper urinary tract in the pediatric age group].

MR imaging is being increasingly used for the diagnosis of congenital urinary tract obstruction. The following conditions have to be fulfilled to provide an MR urography technique which is useful for the pediatric age group: (1) the combination of morphology and function, (2) a high-resolution morphological image, (3) a morphological image independent of kidney function, (4) reliable determination of split renal function and (5) of urinary excretion. This is best accomplished with a combination of a T1-weighted fast GE sequence post-contrast and a heavily T2-weighted 3D IR-TSE sequence. Selected sequence parameters are important for optimization as well as for a correct functional assessment. Then MR urography is superior to the conventional methods of excretory urography, ultrasound, and scintigraphy in the morphological depiction of the urinary tract even of complex malformations as well as in a detailed functional assessment. In particular, this method is useful in the situation of complicated duplex kidneys, dystopic kidneys, unclear morphology, or discrepant former results and perioperative assessment. The main advantages are avoiding radiation and obtaining a simultaneous functional-morphological diagnosis.

Child↗
PubMed2005

[Childhood kidney tumors -- the relevance of imaging].

Kidney tumors represent 6.2% of malignant tumors in children. History, clinical course and radiological findings are necessary elements in the differential diagnosis of the different renal tumors. In the case of nephroblastoma, chemotherapy is based solely on the radiological diagnosis without prior histology. In therapy-optimizing studies of the Society of Pediatric Oncology and Hematology, preoperative chemotherapy is performed. Therapy monitoring is performed in the course of and after preoperative chemotherapy to verify tumor response. Radiological staging plays a significant role in deciding on further treatment and in operative planning. Three-dimensional visualization of the abdominal situs can assist preoperative planning. In summary, diagnostic imaging in renal tumors in children plays a role in differential diagnosis, staging, monitoring of therapy, and surgical planning.

Abnormalities, Multiple↗