Biomedical subjects

Johannes Kirchner

Publications and source records attributed to Johannes Kirchner.

7 recordsLinked to original sources

PubMed2004

Multislice computed tomography angiography of the abdominal arteries: comparison between computed tomography angiography and digital subtraction angiography findings in 52 cases.

Since the introduction of multislice CT scanners, CT angiography (CTA) has become a powerful tool for imaging the vascular system. We compare conventional angiography to CTA in the diagnosis of morphological changes in the abdominal aorta and its branches. A retrospective analysis of 52 patients who underwent both multislice CT angiography (MSCTA) and digital subtraction angiography before surgical treatment is presented. All CT examinations were performed after administration of 100 mL contrast medium with a collimation of 4 x 1 mm and a pitch of 7. A standardized evaluation of the axial, multiplanar and 3D reconstructions was performed by two experienced radiologists. Stenoses were classified as high-grade and low-grade, and aneurysms, occlusions and arteriosclerosis were evaluated. The CTA findings were compared with conventional angiography. All aneurysms, occlusions, stenoses and calcifications were diagnosed correctly by CTA in axial and multiplanar projections (sensitivity 1.0; specificity 1.0). The degree of stenosis was overestimated in three cases when using axial projections. Three-dimensional volume-rendered CTA showed a sensitivity of 0.91 for aneurysms, 0.82 for stenoses, 0.75 for occlusions and 0.77 for calcifications. The specificity was 1.0 in all cases. Multislice CT angiography seems to be similar to conventional digital subtraction angiography for abdominal vessels if multiplanar projections are used.

Aged↗

PubMed2003

[Mesenteric ossification in CT indicates sclerosing peritonitis in chronic bacterial infection and pancreatitis].

Sclerosing peritonitis already has been described as a serious complication of the continuous ambulatory peritoneal dialysis. But different other affections of the peritoneum such as chronic bacterial peritonitis and pancreatitis may result in sclerosing peritonitis, too. The symptom is characterised by thickened small bowel walls and peritoneal membranes as well as peritoneal calcifications which can be shown in computed tomography. We demonstrate two cases of peritoneal ossifications due to peritonitis and pancreatitis.

Bacterial Infections↗

PubMed2002

CT fluoroscopy-assisted puncture of thoracic and abdominal masses: a randomized trial.

PURPOSE: We investigated the benefit of real-time guidance of interventional punctures by means of computed tomography fluoroscopy (CTF) compared with the conventional sequential acquisition guidance. MATERIAL AND METHODS: In a prospective randomized trial, 75 patients underwent either CTF-guided (group A, n = 50) or sequential CT-guided (group B, n = 25) punctures of thoracic (n = 29) or abdominal (n = 46) masses. CTF was performed on the CT machine (Somatom Plus 4 Power, Siemens Corp., Forchheim, Germany) equipped with the C.A.R.E. Vision application (tube voltage 120 kV, tube current 50 mA, rotational time 0.75 s, slice thickness 10 mm, 8 frames/s). RESULTS: The average procedure time showed a statistically significant difference between the two study groups (group A: 564 s, group B 795 s, P = 0.0032). The mean total mAs was 7089 mAs for the CTF and 4856 mAs for the sequential image-guided intervention, respectively. The sensitivity was 71% specificity 100% positive predictive value 100% and negative predictive value 60% for the CTF-guided puncture, and 68, 100, 100 and 50% for sequential CT, respectively. CONCLUSION: CTF guidance realizes a time-saving but increases the radiation exposure dosage.

Abdominal Neoplasms↗

PubMed2002

3D CT versus axial helical CT versus conventional tomography in the classification of acetabular fractures: a ROC analysis.

AIM: To assess the diagnostic power of three-dimensional computed tomography (3D CT), axial helical computed tomography (CT) and conventional tomography in the classification of acetabular fractures by interdisciplinary review. MATERIALS AND METHODS: Receiver operating characteristics (ROCs) were assessed for two radiologists and two surgeons blinded to the presence of acetabular fractures in an animal model (a total of 62 porcine hips, 40 of them with artificial acetabular fractures). Main target parameter was the diagnostic accuracy in the classification of the artificial fractures following Judet et al. RESULTS: ROC analysis for radiologists showed A(z) values of 0.83 for 3D CT, 0.81 for axial helical CT, and 0.78 for conventional tomography; differences between the three techniques were not significant (P = 0.46-0.73). A(z) values for the surgeons were 0.87 for 3D CT, 0.68 for axial helical CT, and 0.60 for conventional tomography; 3D CT was significantly better than axial helical CT (P = 0.01) and conventional tomography (P = 0.001). The differences between axial helical CT and conventional tomography were not significant (P = 0.37). CONCLUSION: Acetabular fractures are best classified by 3D CT, followed by axial helical CT and conventional tomography when assessed by surgeons. 3D CT did not provide any additional significant benefit in the classification performed by radiologists.

Acetabulum↗

PubMed2002

A rare cause of pulmonary-renal syndrome.

Diseases affecting both the lung and the kidney have grave prognosis and serious diagnostic and therapeutic consequences. Here, 3 cases of pulmonary-renal syndrome caused by antiphospholipid syndrome are reported. The patients presented with dyspnea, renal insufficiency, pulmonary infiltrates on chest X-ray and areas of ground glass attenuation on computed tomography of the lungs. There were no signs of infectious disease, vasculitis or myocardial insufficiency. Clinical findings, antiphospholipid levels and histological findings in transbronchial and/or renal biopsy proved the diagnosis of antiphospholipid syndrome. Antiphospholipid syndrome is a comparatively rare disorder which is relevant in the differential diagnosis of diseases affecting both lung and kidney and requires specific therapeutic measures.

Adult↗

PubMed2002

[Computer tomography findings in lung tuberculosis].

PURPOSE: Tuberculosis remains the most important infectious disease all over the world. We report on the CT findings of lung tuberculosis. MATERIAL AND METHODS: Standardised retrospective analysis of the computed tomographic examinations in a total of 100 patients suffering from cultural or histological proven pulmonary tuberculosis. RESULTS: The most common finding in our study group were micronodules and lobular opacities accompanied by enlarged lymph nodes. Cavitation and alteration of the bronchial system (esp. bronchial wall thickening) were found less common. The so-called tree-in bud-appearance which had been estimated by other authors to be rather characteristic for active pulmonary tuberculosis was seen in only 12/100 examinations. It is often found in cases showing severe bronchogenic spreading of the disease. CONCLUSION: The active pulmonary tuberculosis does not show any pathognomonic sign but the combination of findings as opacities and cavitation and segmental spreaded micronodules make the diagnosis probable. This holds also for the so-called tree-in-bud appearances which may be rather suggestive but is seen only in cases suffering from severe bronchiogenic propagation.

Adult↗

PubMed2001

Cowper's syringocele: diagnosis based on MRI findings.

An 8-year-old boy presenting with intermittent haematuria and dysuria was investigated with voiding cystourethrography (VCUG), urethroscopy and perineal MRI. VCUG and urethroscopy did not provide a definitive diagnosis, while MRI clearly demonstrated a homogeneous, oval cystic lesion extending from the bulbourethral glands and slightly impressing the bulbous urethra. The patient was found to have an imperforate Cowper's syringocele. Treatment consisted of marsupialisation and the patient became symptom free. To the authors' knowledge, this is the first description of the MRI characteristics of an imperforate Cowper's syringocele in a paediatric patient.

Bulbourethral Glands↗