Biomedical subjects
Publications and source records attributed to P Hübsch.
Pneumonias caused by Candida glabrata are extremely rare and occur almost exclusively in immunocompromised patients. We report an atypical case of Candida glabrata pneumonia in a non-immunocompromised patient and describe the imaging findings on digital radiography and computed tomography.
Case report of a 22-year old patient with most severe idiopathic bronchiolitis obliterans and organising pneumonia. We discuss the diagnostic algorithm and emphasise the role of CT.
To assess the effect of chronically elevated plasma growth hormone (GH) levels on bone metabolism and bone mineral density (BMD), 16 patients (10 females and 6 males) with a mean age of 49.1 +/- 13.2 years (range 33-68) with active acromegaly were studied and compared to a control group of 16 sex- and age-matched subjects. BMD of the lumbar spine and two different sites of the proximal femur were measured by dual-energy x-ray absorptiometry (Norland XR-26). In the acromegalic patients the mean plasma GH concentration was 30.1 +/- 11.1 micrograms/liter, and the mean plasma somatomedin C (SMC) concentration was 6.5 +/- 1.5 U/liter. Mean serum osteocalcin (OC) levels (14.3 +/- 1.1 versus 7.2 +/- 0.4 ng/ml, p < 0.001) as well as the urinary hydroxyproline excretion (OHP; 8.8 +/- 1.4 versus 2.7 +/- 0.3 mg, p < 0.0001) were significantly higher in the acromegalic patients than in the control subjects. In the acromegalic patients BMD was significantly elevated in the two examined regions of the proximal femur, that is, the femoral neck (1.06 +/- 0.05 versus 0.86 +/- 0.03 g/cm2, p < 0.05) and Ward's triangle (0.92 +/- 0.06 versus 0.76 +/- 0.03 g/cm2, p < 0.02), whereas the BMD of the lumbar spine was not significantly different from that of control subjects. Among the patients with acromegaly a significant positive correlation between serum OC concentrations, on the one hand, and urinary OHP excretion (r = 0.7, p < 0.004) as well as BMD in the proximal femur (r = 0.64, p < 0.007), on the other hand, could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)
The so-called ureter jet is a well known phenomenon, which consists of echoes due to turbulent urine flow emanating from the ureteral orifices during forced diuresis. These motion phenomena are also visible in colour Doppler examinations. In analogy to the ureter jet we could demonstrate different colour phenomena in the normal (n = 20) and stenosed (n = 14) male urethra during voiding by using colour coded Doppler sonography. These observations are obviously caused by turbulent urine flow. In an experimental study, this hypothesis could be verified. Because certain intraurethral colour phenomena are related to stenoses of the urethra, and because their intensity depends on the degree of stenosis and on urine flow (in ml/s), it seems to be possible to draw conclusions on the urodynamic consequences of a stenosis in the urethra by means of colour coded Doppler sonography.
In a retrospective study, 198 contrast venographies were evaluated by two blinded observers for quality of opacification of the venous system and quality of documentation. There was good correlation between the two observers in 91% of the cases. They found an adequate contrast quality in 183 cases (92.4%), while in 15 cases (7.6%) incomplete contrast was found in some parts of the calf or pelvic veins. Most venograms (195, or 98.5%) were adequately documented. In conclusion, contrast venography is an excellent method for evaluation of the venous system, if performed adequately. Nevertheless, there is room for improvement of both technique and documentation.
Of all the forms of osteoporosis, the postmenopausal type is the most important in social medicine due to the potentially high fracture risk in aging. The positive effects of physical activity on bone density have been emphasized in several studies. In this study on 31 female volunteers (minimum age 50 years), who had been postmenopausal for at least 2 years, 16 underwent systematic strength building (training group). They were compared with a control group consisting of 15 female volunteers. The parameters of success were physical strength and bone mineral density (BMD) before and after training. BMD was measured by dual-energy X-ray absorptiometry. The subjects in the control group showed significant decrease in bone density after 6 months: between 6.7 and 22.3% of the values measured at the beginning. The loss was more evident in the proximal femur than in the lumbar spine. In contrast, the subjects in the training group only showed a marginal decrease in bone density in the proximal femur: 0.8 to 3.8% of the earlier values. In the lumbar spine there was even a slight increase (+0.3%) in bone density.
Acromegaly is regarded as a cause for secondary osteoporosis, whereas recent papers suggest that growth hormone increases bone mineral density (BMD). In 16 patients with active acromegaly we found an increased BMD compared to normal controls in the lumbar spine and the proximal femur by means of dual energy X-ray absorptiometry. This increase in BMD was statistically significant in the femoral neck and in Ward's triangle (P = 0.05). Moreover, no signs of osteoporosis were found radiologically.
In 30 children with renal allografts the diagnostic validity of pulsed Doppler (PD) versus colour coded Doppler (CD) sonography was assessed prospectively. 46 PD examinations were performed calculating the resistive index (RI) in the segmental arteries in comparison to 46 CD scans, where renal blood flow throughout the grey-scale image was displayed. In addition, point-spectral analysis with calculation of the RI was also performed on the CD scans. The time for examination ranged from five to ten minutes for the PD and from three to five minutes for the CD study. Concordant findings for the PD and CD technique were generally obtained (normal blood flow pattern on PD-excellent visualization of renal blood flow on CD, reduced or reversed diastolic flow on PD-poor visualization of renal blood flow on CD). There was close correlation of the RI values obtained by the PD and CD scans. CD sonography facilitated point-spectral analysis in shortening the time for examination. The ability to visualize focal hemodynamic alterations provided a higher diagnostic accuracy in comparison to PD sonography.
There are several papers suggesting that colour-coded Doppler sonography is a useful diagnostic tool for the differentiation of malignant and benign lesions of the thyroid gland. This hypothesis (hypervascularization of malignant nodules) is reconsidered by preoperative examination of 65 patients by using colour-coded Doppler sonography and scintigraphy. Among these patients 21 carcinomas and 2 malignant lymphomas of the thyroid gland were found histologically. Colour-coded Doppler sonography was true positive in 10 cases, true negative in 28 cases, false positive in 14 cases and false negative in 13 cases. Our conclusion is that colour-coded Doppler sonography cannot be used unconditionally for the detection of carcinoma of the thyroid gland.
By means of colour-coded Doppler sonography we studied retrospectively the incidence of postoperative changes in 54 patients following 58 carotid endarterectomies. The interval between operation and ultrasound varied from one to 41 months. The overall incidence of recurrent carotid disease was 50% with a 31% (18 of 58) of hemodynamically insignificant restenoses, a 13.8% (8 of 58) incidence of haemodynamically significant restenoses, and a 5.2% (3 of 58) of occlusions. The segment that had been endarterectomized showed a bulbous dilatation in 24.1% (14 of 58). In all of these cases extensive flow reversal zones could be demonstrated, the possible importance of which is discussed. Examinations in 9 patients with reimplantation of subclavian artery to the common carotid artery and grafting technique between these arteries and in 11 patients with reimplantation of vertebral artery to the common carotid artery demonstrated one occlusion of the ipsilateral vertebral artery.
The value of colour Doppler sonography in the diagnosis of renal artery stenosis has been studied retrospectively. 17 patients were examined (34 main renal arteries and 7 accessory renal arteries; ages 37 to 84 years; 7 males and 10 females). We studied 1) ability to study the main renal arteries, 2) visibility of accessory renal arteries and 3) the sensitivity and specificity of colour Doppler sonography for the diagnosis of renal artery stenosis. The results were compared with intraarterial angiography. Demonstration of the main renal arteries with colour Doppler sonography was possible in 23 of the 34 vessels. Not a single of the 7 accessory renal arteries was demonstrated by colour Doppler sonography. Of 8 angiographically demonstrated stenoses (more than 50% narrowing) 2 were missed by colour Doppler sonography. One stenosis was correctly diagnosed and 5 were incorrectly evaluated by sonography. 16 out of 18 angiographically normal main renal arteries were correctly evaluated by colour Doppler sonography but 2 showed a false positive finding. This results in a sensitivity of 17% and a specificity of 89% per kidney. Colour Doppler sonography cannot be recommended as a screening method for renal artery stenosis in view of its limited accuracy.
The diagnostic value of pulsed Doppler sonography for the detection of renal artery stenosis was questioned by recent studies. Until now, the diagnostic value of colour-coded Doppler sonography of the renal arteries is not clearly defined in relation to pulsed Doppler. This study deals with specific problems of colour-coded Doppler sonography in the examination of the renal arteries. Because of basic technical principles of colour-coded Doppler sonography a stenosis can be imitated especially at the origin of the right renal artery by using a ventral approach to the vessel. This pseudo-stenosis is due to a change of colour similar to an aliasing-phenomenon in a curved vessel. In order to avoid false positive results, a laterodorsal approach to the vessel should be applied additionally. A spectral waveform should be also registered routinely.
Color-coded Doppler sonography (CCDS) was used for the examination of tumor thrombus (n = 7) and benign thrombosis (n = 6) of the inferior vena cava. Tumor thrombus was due to hepatocellular carcinoma in two cases and to renal cell carcinoma in five cases. Whereas no specific information about the nature of thrombus formation could be gained by gray scale sonography, a typical patchy vascularization pattern was noted within tumor thrombi in six of seven cases using CCDS. This ws due to marked neovascularization within the tumor thrombi, confirmed by histologic examination in all cases. In one patient no vascularization within the tumor thrombus could be observed by CCDS because the thrombus was relatively small. In patients with bland thrombosis, either no vascularization of the thrombus was seen (n = 5) or linear recanalization of the thrombus occurred (n = 1). Therefore, it might be possible to differentiate tumor from nontumor thrombus in the inferior vena cava by using CCDS. Further studies are needed to confirm this preliminary hypothesis.
Measurements of bone mineral density (BMD) of the proximal femur (including femoral neck, Ward's triangle and trochanteric region) were compared with the Singh index grading in 40 normal subjects (20 male, 20 female) and in 116 patients (18 male, 98 female) referred for assessment of possible osteoporosis. Additionally, the BMD and the Singh index of 12 cadaver specimens (6 male, 6 female) of the proximal femur were compared with each other and with the histomorphology of the femoral necks of the specimens. Although there was a good correlation of Singh index with BMD in the group of male patients with suspected osteoporosis and in the series of bone specimens, there was a poor correlation in the group of female patients as well as in the normal controls and in the patient population as a whole. There was also poor correlation of Singh index values with histomorphologic data, whereas the BMD measurements correlated well with the amount of calcified bone found histologically in the femoral necks of the bone specimens. We conclude that the Singh index cannot be used to predict BMD of the proximal femur accurately.
By using colour coded Doppler sonography and duplex Doppler sonography, the presence of AV-shunts could be demonstrated correctly in 15 patients with arteriovenous malformations (angiographic correlation was obtained in 10 cases). The feeding vessels could not be identified exactly in all cases by using duplex Doppler sonography; correct identification of the feeding vessels was possible in only 2 patients by using colour coded Doppler sonography. In one patient, a soft tissue tumour could be diagnosed sonographically (histology: malignant synovialoma). Therefore, colour coded Doppler sonography serves as an important supplement to angiography in the diagnostic evaluation of arteriovenous malformations, but cannot replace it.
Nine patients with a cervical tumour, diagnosed by duplex Doppler sonography were additionally evaluated by colour-coded Doppler sonography (CCDS). The duplex Doppler diagnosis of three internal carotid artery aneurysm was confirmed by CCDS in only one patient. In the remaining two cases CCDS identified a marked coiling of the internal carotid artery. Three low echogenic lesions, interpreted as cervical lymphomas by conventional Doppler sonography were identified as two internal carotid aneurysm with partial thrombosis and a carotid body tumour in the third patient by CCDS. Duplex-Doppler sonography and CCDS agreed in the diagnosis of two AV-malformations and one carotid body tumour. Angiography confirmed the CCDS-diagnosis in 7 patients. In the two patients with coiling of the ICA angiographic evaluation was not performed. Thus, CCDS was superior to duplex Doppler sonography in the evaluation of vascular lesions of the extracranial section of the carotid artery and provided additional diagnostic information.
Common carotid artery occlusion is not necessarily associated with thrombosis of the ipsilateral internal carotid artery. Noninvasive imaging of the carotid bifurcation with colour-coded Doppler sonography demonstrated patency of the external and internal carotid arteries distal to a common carotid occlusion in 4 patients which could be proven surgically. Identification of internal carotid artery patency could be demonstrated by angiography in two of the patients while in the other two cases angiography was inconclusive. Thus, CCDS provided a correct diagnosis of the internal carotid patency in these patients with common carotid occlusion.
In a retrospective study stage grouping as well as histopathological grading (G category) of colorectal carcinomas was compared to radiographic findings at double contrast barium enema. A good correlation of tumour stage according to Dukes and the pT category and histopathological grading could be established to radiographic morphology. Apple core lesions and eccentrically obstructing neoplasms as well as saddle-like tumours exhibited worse staging and grading categories in comparison to polypoid lesions; plaque-like tumours are probably in between. It can therefore be assumed that the radiographic appearance of colorectal carcinomas may be a valuable tool to indicate stage group and G-category and thus offer information about patient prognosis.