Inelastic leg compression is more effective to reduce deep venous refluxes than elastic bandages.

BACKGROUND: Deep venous refluxes play an important triggering role for the development of venous leg ulcers. Compression therapy is able to reduce these refluxes depending on pressure and the kind of material being used. OBJECTIVE: To compare the efficacy of compression bandages of varying pressure and material (elastic, long-stretch versus inelastic, short-stretch bandages, four-layer bandages). METHODS: Venous volume (VV) and venous filling index (VFI) as a quantitative parameter of venous reflux were measured using an airplethysmograph (APG) in a total of 21 patients presenting with venous leg ulcers and deep venous refluxes. Bandage pressure was measured in every experiment. The influence of elastic and inelastic bandages with increasing pressure and the changes in these parameters using different bandages with the same pressure were investigated. RESULTS: The initial median value of VFI without compression was 8.45 ml/sec. VV and VFI were significantly reduced by increasing external pressure, more strongly with inelastic than with elastic material. With a pressure of 25 mmHg inelastic bandages diminished VFI to a median of 3.25 ml/sec while the elastic material did not even approach this value with a pressure of 40 mmHg (4.25 ml/sec). Applying bandages of different material with the same pressure of 30 mmHg, the most intense reduction of VV and VFI was obtained by inelastic and by four-layer bandages. The effect on venous reflux was statistically significantly superior with inelastic compared to elastic material. CONCLUSION: Using the same bandage pressure, inelastic material is more effective at reducing deep venous refluxes than elastic bandages in patients with venous ulcers. Four-layer bandages show similar efficacy to inelastic bandages.

Improved automatic separation of renal parenchyma and pelvis in dynamic renal scintigraphy using fuzzy regions of interest.

The aim of the study was to examine the physiological relevance of factors produced by a modified procedure for factor analysis of dynamic renal studies. Factor analysis has been applied locally to subsets of dynamic renal data which were well defined in both space and time domains. Optimised factor images resulting from different subsets were used as fuzzy regions of interest (ROIs) for the extraction of time-activity curves corresponding to renal parenchyma, renal pelvis, vascular and spatially homogeneous background. The original procedure employed the factor images of renal parenchyma and pelvis resulting from an analysis of the interval between the peaks of parenchymal and pelvic curves. In an attempt to improve the separation of renal parenchyma and pelvis, new fuzzy ROIs were used. They correspond to the factor image of renal uptake obtained from the analysis of the early phase of the study, and to the factor image of the renal pelvis obtained from the outflow phase. The curves generated with the new fuzzy ROIs were compared with those of the original procedure and tested for the presence of known artefacts inconsistent with the expected physiological behaviour. Unlike with the original procedure, no such artefacts were found. The most striking difference was that the pelvic factor curves did not start from zero time of the study but exhibited a physiologically correct initial horizontal zero segment the length of which correlated closely with the minimum parenchymal transit time (r=0.79, n=46, P<0.001). The new method permits easy and reliable application of factor analysis to dynamic renal studies. Problems which remain to be solved are user-independent identification of the optimum factors and suboptimal performance of the method under extreme conditions. Our results provide additional evidence that factor analysis can extract physiologically relevant information quantitatively from dynamic scintigraphic data.

[Incidence of pulmonary embolism in venous thrombosis]. / Die Häufigkeit der Lungenembolie bei venöser Thrombose.

The frequency of pulmonary embolism in patients with deep vein thrombosis can be assessed by pathological-anatomical and by nuclear medical studies. The frequency of deep vein thrombosis in autopsies ranges from 23.7% to 62%, by inclusion of microscopic thrombi the frequency increases to 72%. In most cases the localisation of the venous thrombosis is bilateral. In cases of venous thrombosis the frequency of pulmonary embolism is 52 to 79.4%, if microscopic thrombi are included, the number is 87.8%. 7.8% to 78.9% of all pulmonary emboli are considered as cause of death or severely contributing to death. The fatal embolisms originate preferentially from iliofemoral thrombosis. About 1/10 of all emboli originate from V. cava sup. and the right heart. In a small number of pulmonary emboli the origin could not be detected. The rate of correct intra vitam diagnosis is low, not more than 11 to 25% of all pathological-anatomical proven emboli had a correct diagnosis during life. In fatal pulmonary embolism the correct clinical diagnosis was made in 1/3. In nuclear medicine studies pulmonary embolisms are searched for from the clinical suspicion or the diagnosis of deep vein thrombosis with the perfusion-/ventilation- or inhalation scintigraphy. Patients with deep vein thromboses showed in 38 to 57.9% pulmonary embolism. In 80% of all pulmonary embolism multiple perfusion defects (2 to 9 perfusion defects) were detected, the lesions were evenly distributed in both lungs. The frequency of pulmonary embolism in calf vein thrombosis was 46%, in leg vein thrombosis 67% and reached 77% if the pelvic veins were involved. It is remarkable that the majority of all pulmonary emboli (46.3% to 100%) showed no clinical symptoms. The knowledge about the high frequency of pulmonary embolism in patients with deep vein thrombosis can improve the diagnosis of pulmonary embolism. For the diagnostic process of pulmonary embolism the presence of acute deep vein thrombosis increases the pre-test probability (prevalence of more than 50%). Every positive test for pulmonary embolism will gain a very high post-test probability according to Bayes' theorem.

[Isotope lymphography--possibilities and limits in evaluation of lymph transport]. / Isotopenlymphographie--Möglichkeiten und Grenzen der Beurteilung des Lymphtransportes.

Quantitative isotopic lymphscintigraphy is based on a combination of transmission- and emission scintigraphy correcting the different depths of lymph nodes. This method allows an exact estimation of lymph-transport in legs during standardised stress. The depth-corrected uptake in the lymph nodes expressed in percentage of the injected dose (D%) reflects the lymph-transport. After s.c. injection of 1 mCi of 99 m Tc-microcolloid (Nanocoll) the prefascial lymph-transport and after intramuscular (i.m.) injection the subfascial lymph-transport can be assessed. The stress consists of 15 minutes walking on a horizontal treadmill at a speed of 3.2 km/h. After s.c. injection all types of lymphedema can be diagnosed (average uptake in lymphedema 2.0 +/- 2.5 D%, in normal legs 14.3 +/- 4.2 D%; p < 0.001). The subfascial transport is much lower, only 7.7% of the prefascial transport. In healthy legs the uptake after i.m. injections is 1.1 +/- 0.8 D%, in postthrombotic syndrome the uptake decreases to 0.2 +/- 0.16 D% (p < 0.02). Lymphscintigraphy after i.c. injection of the colloid reveals contradictory results. The uptake is very low only in lymphedema with involvement of the whole leg. In distal and in secondary lymphedema the uptake is near the normal range. The clearance rate of the tracer from the depot is not reliable for diagnosing lymphedema. Information may be gained concerning the following points: quantitative measurement of lymph transport, routine diagnosis of lymphedema, follow-up in lymphedema, assessment of pre- and subfascial lymph-transport in patients with venous diseases, angiodysplasias etc., documentation of therapeutic effects.

[Value of inflammation and bone scintigraphy in differential diagnosis of painful affections of small joints]. / Wertigkeit der Entzündungs- und Knochenszintigraphie in der Differentialdiagnose schmerzhafter Affektionen kleiner Gelenke.

It was the aim of this study to evaluate different markers of inflammation such as 99mTc-labelled human immunoglobulin G and 99mTc-nanocolloid with respect to their ability to detect inflammatory or degenerative affections of small joints of hand and fingers. While conventional bone scanning reveals good agreement with clinical findings it is not well suited for screening of inflammatory processes due to its poor specificity. In small joints conventional three-phase bone scan with information of perfusion, bloodpool and accumulation is not suitable due to the small ROI, low count rate with high statistics. Therefore we used inflammatory markers to overcome this problem. Immunoglobulin G was true positive in case of inflammatory lesions in 69%, and false positive in case of degenerative lesions in 24%, while nanocolloid was true positive in 72% and false positive in 14%, respectively. Significant differences were found between markers of inflammation and the bone scanning agent while both inflammatory markers, immunoglobulin G and nanocolloid demonstrated significant correlation. While bone scanning tracers detect all kinds of joint affections, immunoglobulin G and nanocolloid accumulate preferentially in inflammatory joints and therefore might be useful to differentiate between inflammatory and degenerative lesions.

The incidence of hyperthyroidism in Austria from 1987 to 1995 before and after an increase in salt iodization in 1990.

Between 1963 and 1990, Austria had iodized salt prophylaxis of endemic goitre with 10 mg KI (7.5 mg I) per kg. This was obviously insufficient, as urinary iodine excretion ranged from 42 to 78 microg I per g of creatinine and goitre in adults remained in the endemic range of 15%-30%. Therefore salt iodization was doubled in 1990. The aim of this study was to assess the annual incidence of different types of hyperthyroidism (HT) before and after this increase in salt iodization. The incidence of HT was recorded in 14 nuclear medicine centres from 1987 to 1995. In five additional centres data were available from 1992 onwards. Data prior to 1992 were documented retrospectively, while those after 1992 were recorded prospectively. The 14 centres drew patients from an area with a population of approximately 4.23 million while all 19 institutes were estimated to cover an area with a population of 5.4 million (the total population of Austria is 7.86 million). A total of 414232 persons were examined for the first time in the participating centres. HT and the type of HT were defined by clinical examination, serum TSH, thyroid hormone levels in blood, ultrasonography, scintigraphy and serum autoantibody titres. HT was classified into immunogenic HT (Graves' or Basedow's disease, GD) and HT with intrinsic thyroid autonomy (uni-, multinodular or disseminated Plummers' disease, PD). HT was also divided into overt (o) or subclinical (sc) disease. The following data were calculated: annual incidence per 100000 and the relative risk (RR) for HT with 95% confidence intervals (CI). In addition, linear trends were calculated for each type of HT by means of logistic regressions. In the 19 centres a total of 47834 patients with HT were registered from 1987 to 1995. PD accounted for 75% of all cases of HT and GD for 19%, while other types of HT were present in 6%. From 1987 to 1989 (time period T0), the annual incidence of oPD was 30.5 (95% CI 29.6-31.5) per 100000. The RR compared to the baseline period T0 was highest in 1992 (1.37; 1.3-1.45) and decreased to 1.17 (1.1-1.24) in 1995. The annual incidence of scPD in T0 was 27.4 (26.5-28.3) per 100000. The RR was highest in 1991 (1.64; 1.56-1.73) and was 1.60 (1. 51-1.69) in 1995. In oPD and scPD a higher RR was observed in persons older than 50 years of age, particularly in men. The incidence of oGD in T0 was 10.4 (9.8-10.9) per 100000; the maximum RR increased to 2.19 (2.01-2.38) in 1993 and decreased to 1.95 (1.78-2.13) in 1995. The incidence of scGD was 1.9 (1.6-2.1) in T0. The maximum RR was observed in 1994 (2.47; 2.04-3.0) and it was still 2.26 (1.85-2.77) in 1995. The increased incidence of oGD and scGD was evenly distributed in all ages and both sexes. The time course of different types of HT following the increase in salt iodization could be divided into two phases: an increase in the incidences of HT with peaks after 1-4 years and a subsequent decrease, the only exception being scGD. The effect was more pronounced in GD than in PD. PD showed an age and gender dependency over time, while GD did not.

The effect of mobilisation of patients during treatment of thromboembolic disorders with low-molecular-weight heparin.

OBJECTIVE: To elucidate the risk of pulmonary embolism (PE) in patients with deep vein thrombosis (DVT) who are kept walking with compression bandages. EXPERIMENTAL DESIGN: Perfusion/ventilation scanning of the lungs was performed at admission and after 10 days of treatment. SETTING: General community hospital. PATIENTS: A total of 631 consecutive patients were studied (upper limit of the thrombi: iliofemoral vein, n=212; femoral or popliteal vein, n=302; lower leg, n=117). The patients received different dose regimens of low-molecular-weight heparin (dalteparin) subcutaneously. RESULTS: The study revealed that the prevalence of PE at baseline was between 45.1% and 51% (95% CI 38.2-55.2 and 45.2-56.8% respectively) in patients with proximal DVT, and 31.9% (95% CI 23.6-41.2%) in those with DVT restricted to the lower leg. The majority of these cases of PE were completely asymptomatic. The incidence of a new PE, revealed by a second lung scan on day 10 after admission, was 7.0% (95% CI 3.9-11.4%) in patients with iliofemoral DVT, 5.5% (95% CI 3.2-8.7%) in those with femoropopliteal DVT and 2.7% (95% CI 0.6-7.6%) in those with lower-leg DVT. These incidence rates for new PEs were significantly lower than the rates previously reported (p<0.01). The fatality rate was also lower compared with the literature: one patient suffered a fatal PE (0.2%; 95% CI 0-0.9%), four patients died from malignant tumours, and one from pneumonia. The frequency of malignant tumours was greater in this study than in the literature (23% in patients with iliofemoral DVT, 14% in those with femoropopliteal DVT and 9% in those with DVT of the lower leg). CONCLUSION: Mobile patients with DVT do not need bed-rest. Low-molecular-weight heparin s.c., compression bandages and walking exercises make home-treatment of DVT feasible.

Frequency of pulmonary embolism in patients who have iliofemoral deep vein thrombosis and are treated with once- or twice-daily low-molecular-weight heparin.

PURPOSE: The purpose of this study was to compare the efficacy and safety of treating mobile iliofemoral patients with deep venous thrombosis (DVT) with subcutaneous low-molecular-weight heparin (dalteparin sodium) either 200 IU/kg once-daily (group 1) or 100 IU/kg twice-daily (group 2). METHODS: Consecutive patients with suspected iliofemoral DVT diagnosed by duplex ultrasonography and verified by radionuclide venography were randomized to one of the two low-molecular-weight heparin (LMWH) regimens. Perfusion and when necessary ventilation scans were performed for diagnosis of pulmonary emboli (PE) in all patients immediately after admission and were repeated after approximately 10 days, whereupon oral anticoagulation was started unless contraindicated. Minimal and maximal anti-factor Xa activity was measured after 2 to 3 days of therapy. All patients were kept mobile with compression bandages. The primary end point was reduction in frequency of PE as assessed on the second lung scan. RESULTS: A total of 140 patients with confirmed DVT were randomized, 76 to group 1 and 64 to group 2. The two groups were comparable in their baseline clinical characteristics. In the initial lung scans 36 (47.4%) patients in group 1 and 29 (45.3%) patients in group 2 had objectively verified PE, but only 11 (14.5%) and 8 (12.5%) patients, respectively, had symptoms. After dalteparin treatment PE disappeared in two patients in group 1, but in two other cases new PEs occurred, (NS). In group 2 a resolution of PEs was observed in eight patients, whereas only one new PE could be detected. This change reflects the efficacy of therapy as defined by resolution of existing PEs and by the occurrence of new PEs and is statistically significant according to McNemar's chi-square test with the exact binomial method pair procedure (p < 0.05). Symptomatic PE was reduced from 14.5% to 5.3% in group 1 (96% to CI for the difference, -1.5% to +17.3%) and from 12.5% to 1.6% in group 2 (95% CI for the difference 0.7% to 18%, p < 0.05). There was one single fatal PE, one serious and three minor bleeding episodes in group 1, and one minor bleeding episode in group 2 (95% CI for the difference: -3.6% to +8.1%). CONCLUSIONS: Treatment of ambulant iliofemoral patients with DVT with 100 IU/kg dalteparin twice-daily appears to be moe safe and effective than 200 IU/kg given once-daily. Bed rest is not necessary for treating mobile patients.

[Thallium scintigraphy of the myocardium. Uniform research protocols of the Austrian Society for Nuclear Medicine]. / Die Thalliumszintigraphie des Myokards. Einheitliches Untersuchungsprotokoll der Osterreichischen Gesellschaft für Nuklearmedizin.

A uniform protocol for thallium scintigraphy of the myocardium has been issued in Austria to avoid difficulties in interpreting results and to avoid repeated examinations to save expenses and radiation burden. From the beginning of 1995 this protocol will be used in the Austrian departments of Nuclear Medicine, differences from this protocol have to be mentioned separately. In this protocol the procedure of examination, bicycle and pharmacological stress testing and vasodilatation, acquisition techniques for planar and SPECT imaging, data processing and quality control of devices are defined.

[Involvement of the lymphatic system in post-thrombotic syndrome]. / Die Mitbeteiligung des Lymphsystems beim postthrombotischen Syndrom.

The involvement of the lymphatic drainage in patients with postthrombotic syndrome can be verified by (quantitative) isotopic lymphography (99m Tc labelled microcolloids) and by indirect lymphography (water-soluble contrast medium Iotrolan). Both methods point to an augmented praefascial lymph-transport. In the region of lipodermatosclerotic skin changes dermal backflow can be explained by a local damage of peripheral skin-lymphatics ("localized lymphoedema"). No working lymphatics can be found in the border of ulcers. As could be demonstrated by intramuscular injection of the radioactive tracer subfascial lymphtransport is decreased not only in the postthrombotic stage but already in the acute phase of a deep vein thrombosis. The alterations of the lymph-drainage in a postthrombotic syndrome may have some pathophysiological importance for the development of the tissue changes and may also explain some clinical signs.

Postocclusive reactive hyperemia and postural vasoconstriction in different kinds of leg ulcers--investigations with laser Doppler.

Laser-Doppler fluxmetry was performed in 42 patients with leg ulcers (18 venous, 8 arterial, 12 diabetic-arteriolar and 4 mixed arterio-venous) and in 9 healthy controls. Using a bipolar probe measurement was carried out at the ulcer border and on the dorsum of the foot in the supine and in the sitting position. Reactive hyperemia after three minute arterial occlusion was produced in both body-positions. In every ulcer-group resting and peak fluxes showed a statistically significant increase in the ulcer region as compared to normal skin of the lower leg in the control group, the quotient between peak and resting flux ("reactive hyperemia index" RHI) being significantly lower. The RHI values for four ulcer-patients with a dramatic deterioration worsening eight months later were close to one, while the unchanged and improved cases showed median values above 1,2. Sitting up was followed by a decrease of flux in all ulcer-groups as well as in the control group. On the dorsum of the foot there was an increase of the laser Doppler flux in patients with arterial occlusive disease, i.e. in the group with arterial and mixed ulcers. This study shows that the kind of microcirculatory flow damage is not different in various causes of ulcerations. The reduced reactive hyperemic response compared to the increased resting fluxes (amount of RHI-decrease) might be a useful predictor for healing or non-healing of the ulcer.

[Nuclear medicine studies of tissue concentration and hemodynamic effects of retrograde intravenous pressure infusions]. / Nuklearmedizinische Untersuchungen zur Gewebekonzentration und hämodynamische Effekte von retrograden intravenösen Druckinfusionen.

In 12 patients with trophic foot-lesions (diabetic feet) retrograde intravenous pressure infusions (150 ml) containing radioactive tracers (99m Tc, 99m Tc labelled human serum albumin) were carried out. With the veins emptied time-activity curves over the legs reflect tissue concentrations after release of the occlusion. Tissue-concentration is about 3 times higher than after intraarterial and 7 times higher than after intravenous injection of the same dose. The high count-rates which can be measured in the wound-secretion demonstrate the "rinsing effect" of the injected fluid. Hemodynamic investigations have been performed in a double blind study. 8 patients received buflomedil and 9 got placebo 3 times per week by retrograde intravenous pressure infusions. After 3 weeks there was an increase of the peak-flow on the lower leg (venous occlusion plethysmography), an increase of transcutaneous oxygen pressure and a fall of peak flow-time and of plasma-viscosity, both for buflomedil and for placebo (without statistical significance). Preliminary investigations after an arterial occlusion for 1 hour showed an increase of flow-values measured by venous occlusion plethysmography which reached a maximum after 4 to 5 days.

99mTc-DTPA aerosol for same-day post-perfusion ventilation imaging: results of a multicentre study.

A multicentre study was performed in an attempt to evaluate a submicronic technetium-99m diethylene triamine penta-acetic acid aerosol generated by a newly developed delivery system, the aerosol production equipment (APE nebulizer), for same-day post-perfusion ventilation imaging in patients with clinically suspected pulmonary embolism. Quantitative comparison between the DTPA aerosol and krypton gas demonstrated a close correlation with respect to regional pulmonary distribution of activity and peripheral lung penetration (n = 14, r = 0.94, P < 0.001 and r = 0.75, P < 0.0025, respectively). In 169 consecutive patients, DTPA aerosol images performed immediately following perfusion (inhalation scan I) were compared to those carried out on the next day (inhalation scan II) with respect to image quality and assessment of perfusion-ventilation matches or mismatches. Agreement between inhalation scans I and II with respect to perfusion defects matched or mismatched to ventilation was found in 166/169 (98%) studies. The image quality of inhalation scan I was equal to that of scan II in 72%; inhalation scan I was superior in 11% of cases, while scan II was superior in 17%. This submicronic 99mTc-labelled DTPA aerosol is well suited for fast same-day post-perfusion ventilation imaging in patients with clinical suspicion of pulmonary embolism.

[Diagnosis of lung embolism]. / Zur Problematik der Diagnose der Lungenembolie.

Although lung scanning has been performed for nearly 3 decades, the diagnosis of pulmonary embolism (PE) still remains problematic. Only about 20% of all autopsy proven cases of PE have been diagnosed during life time. Biello, and later authors of the PIOPED study defined 3 probability levels for perfusion/ventilation (inhalation) scan interpretation in comparison with pulmonary angiography: High probability (about 90% PE), indeterminate (27 to 50% PE) and low probability (about 5% PE). If the scan results are in the high and low probability group, the diagnostic procedure can be stopped. However, in the indeterminate group including 36 to 52% of all patients, diagnosis should be confirmed by pulmonary angiography. This diagnostic procedure is not well accepted by clinicians, only 0 to 15% of all patients suspected of PE undergo angiography. The diagnostic problem is more complicated due to the large amount of clinically silent PE (39 to 59% of all PE). The inclusion of the diagnosis of thrombosis ("thromboembolism") into the diagnosis of PE increases the pre-test probability for PE to 55 to 60% (= prevalence of PE in patients with deep vein thrombosis). According to Bayes' theorem, the post test probability then exceeds 95%. Without considering thrombosis, the pre-test probability is very low and therefore the post-test probability of a pathologic scan is markedly lower than 50%.

[Contribution of nuclear medicine to management of pulmonary complications in patients with acquired immune deficiency]. / Beitrag der Nuklearmedizin zum Management pulmonaler Komplikationen bei Patienten mit erworbener Immunschwäche.

Opportunistic lung infections and malignancies are life-threatening complications in HIV-positive patients. In 72 HIV-positive patients the role of different non-invasive tests such as lung function tests, blood gas analysis, 67 gallium scanning and epithelial lung clearance with 99m Tc-DTPA for the management of these patients was prospectively studied. For all non-invasive tests the mean values of patients with pulmonary complications (n = 25) differed significantly from those of asymptomatic HIV-positive patients (n = 47) (p < 0.001). In 10 patients presenting with acute Pneumocystis carinii pneumonia, 99m Tc-DTPA clearance rates and 67 gallium uptake differed significantly before and after therapy (4.80 +/- 1.23%/min vs 2.47 +/- 0.72%/min and 2.15 +/- 0.42 vs 1.39 +/- 0.18, respectively). Follow-up after therapy revealed different time courses of these tests for normalization. A significant inverse correlation was found between DLCO and 99m Tc-DTPA lung clearance (r = -0.90, p < 0.001, n = 35). A diffuse homogeneous 67 gallium uptake is not diagnostic for PCP, the same pattern was found in a patient with lymphoid interstitial pneumonitis and in patients with CMV pneumonitis; these patients also had accelerated epithelial lung clearance rates. 67 gallium (6/6) was superior to 99m Tc-labelled immunoglobulin G (3/6) for detection of PCP. The 3 patients with Kaposi sarcoma of the lung had negative 67 gallium scans, but positive 201 thallium scans and increased 99m Tc-DTPA clearance rates.(ABSTRACT TRUNCATED AT 250 WORDS)

Frequency of pulmonary embolism in ambulant patients with pelvic vein thrombosis: a prospective study.

One hundred thirty-nine consecutive patients (average age 70.1 years) who were able to walk with a swollen leg were seen at the clinic where diagnosis of acute deep vein thrombosis (DVT) extending to the pelvis was confirmed by injecting microspheres labeled with technetium 99m into the dorsal foot vein (radionuclide venography). Thirty-nine (28%) of these patients had malignant disease. Perfusion lung scans performed immediately after radionuclide venography were supplemented by inhalation scans (99mTc-labeled diethylenetriamine pentaacetic acid aerosol) in case of perfusion defects. During scintigraphy patterns highly indicative of pulmonary embolism (PE) were found in 80 patients (58%), but only 11 (7.9%) had minor clinical symptoms. All patients were admitted to the ward, were given standard heparin subcutaneously (35,000 to 40,000 units/24 hr) and firm bandages, and were encouraged to walk. After 11 days pulmonary scintigraphy was repeated and revealed no change in 55 of 59 patients without PE and in 40 of 80 patients with PE. Thirty-three patients (23.7%) showed regression of perfusion defects. New PE developed in 11 patients (7.9%, four without and seven with previous PE). Autopsy revealed that one 80-year-old patient with prostatic carcinoma had died of massive PE. When comparing this frequency of newly developed PE during ambulation with the occurrence of PE after bed rest, according to the literature, it is no more dangerous for a mobile patient with proximal DVT to walk wearing a firm bandage than it is for the patient to be in bed. Therefore we recommend treating mobile patients with DVT by use of anticoagulation and firm compression bandages and without immobilization.

[Recommendations for carrying out nuclear medicine kidney function tests with a gamma camera and computer]. / Empfehlungen zur Durchführung von nuklear-medizinischen Nierenfunktionsuntersuchungen mit Gammakamera und Computer.

Standardization of nuclear medicine renal studies is required in order to permit the comparison of study results of a patient obtained at different laboratories. Furthermore, standardization is a prerequisite for quality control of the analysis part of the procedure. The guidelines presented here are based on a survey carried out amongst nuclear medicine laboratories in Austria and have been edited and harmonized in a workshop organized by the Austrian Nuclear Medicine Society. The guidelines include detailed descriptions of the requirements of instrumentation, of the methods of acquisition, dosage and radiation dose of the commonly used radiopharmaceuticals and all aspects of the analysis of digital renograms. A comprehensive section deals with the determination of renal clearance from the renogram, further sections cover the usage and recommended methods of captopril renography for the diagnosis of unilateral renal artery stenosis and of the frusemide renogram for the diagnosis of nephropathy and uropathy.

Urine excretion of inhaled technetium-99m-DTPA: an alternative method to assess lung epithelial transport.

Technetium-99m DTPA clearance (99mTc-DTPA) clearance measured by a gamma camera or a scintillation probe not only reflects epithelial transport, but is also influenced by an unknown amount of mucociliary clearance depending on particle size and aerosol deposition. This is confirmed by factor analysis of dynamic inhalation studies. Assessment of epithelial absorption by urinary excretion of inhaled 99mTc-DTPA is largely independent of aerosol lung deposition. Twenty-four-hour excretion reflects the amount of aerosol cleared by absorption, while two-hour excretion is a quantitative measure of the aerosol absorption rate from the epithelium into blood. Urinary 99mTc-DTPA excretion of two aerosols with different particle size correlated significantly (p less than 0.001) with analysis of lung clearance curves. A very similar regression in the form of a cumulative exponential function was found with both aerosols. Two-hour urine values of nonsmokers differed significantly from those of smokers or patients with active interstitial or infectious lung disease. This alternative procedure is suited as a bedside test and holds promise for patient monitoring and follow-up.