Parathyroid scintigraphy protocols in Finland in 2010. Results of the query and current status.

UNLABELLED: The GOAL of this study was to describe current clinical parathyroid scintigraphy (PS) protocols in Finland. METHODS: all departments of nuclear medicine in Finland were contacted, and instructions regarding PS were requested. RESULTS: instructions regarding PS were received from all of the departments that perform PS (n = 19). Seven hundred and sixty-nine PS studies were performed in 2009 (between 7 and 209 per hospital). Three methods of PS were used. The dual-phase method with (99m)Tc-sestamibi is used in seven hospitals, the dual-tracer method with (123)I/(99m)Tc-sestamibi in eleven, and (99m)TcO4/(99m)Tc-sestamibi in one hospital. The activities of 99mTc-sestamibi, 123I and (99m)TcO4 were 150-800 MBq, 10-30 MBq and 50 MBq, respectively. The anterior image with parallel-hole collimators, the anterior image with pinhole collimator, the oblique angles with pinhole collimator, SPECT and hybrid CT with SPECT were acquired in 84%, 26%, 16%, 63%, and 42% of the hospitals, respectively. Because the imaging techniques were combined, one to four acquisitions were performed per patient. Scatter and attenuation correction were used in five protocols. A correction for crosstalk of (123)I and (99m)Tc gamma energies was not used, but the amount of crosstalk was decreased by using narrow or asymmetric energy windows in all dual isotope protocols. CONCLUSION: 19 hospitals used 18 different study protocols. Thus, significant variability exists in the current practice of PS in Finland. The protocols should be tested with known phantoms to determine any differences in sensitivities for detecting small active structures. Further studies with phantoms are needed to determine the optimal imaging techniques. The results of these phantom studies will provide guidelines for proposing national recommendations for PS.

No impairment of peripheral deposition in novel asthmatics treated with an MDI corticosteroid with spacer.

Pulmonary distribution and lung functions were evaluated during a 4-month inhaled corticosteroid treatment period in 10 steroid-naïve novel asthmatics with normal or slightly reduced lung functions. Patients were given a total daily dose of 1000 microg of beclomethasone dipropionate aerosol twice a day via a pressured metered dose inhaler with a large-volume chamber device (Volumatic, GlaxoSmith Kline, U.K.). Gamma lung scintigraphy and lung function tests were performed before and after 2 months and 4 months. Inhaled 99mTc-labelled beclomethasone dipropionate liposomes were used to assess lung deposition patterns during inhaled steroid therapy. Serum eosinophil cationic protein (ECP) concentration was used as a surrogate marker of asthmatic inflammation. Following beclomethasone treatment, all lung functions were enhanced, but only FVC values showed significant improvement. The FEV1/FVC ratio remained slightly reduced in spite of inhaled corticosteroid therapy. However, the association between changes in improved FVC values and reduced ECP levels proved to be statistically significant. In lung scintigraphy, no evidence of changes in pulmonary deposition patterns were seen during the follow-up period. We conclude that inhaled corticosteroid therapy can lead to improvements in lung functions and surrogate markers of airway inflammation in novel asthma without affecting the peripheral deposition pattern of aerosols.

Possibilities of formoterol to enhance the peripheral lung deposition of the inhaled liposome corticosteroids.

The pulmonary distribution and clearance of 99m-Tc-labelled beclomethasone dipropionate (Bec)--dilauroylphosphatidylcholine (DLPC) were compared in nine asthmatic patients on inhaled steroids after a 1-week medical treatment period of long-acting beta2-agonist formoterol. The patients were given formoterol 12 microg (OxisTurbuhaler) twice daily in addition to their own regular inhaled corticosteroid therapy. Gamma lung scintigraphy and lung function tests were performed before and after formoterol treatment. The bronchodilating effect ofthe combined therapy was significant: 1-week usage of inhaled formoterol enhanced peripheral lung deposition of beclomethasone liposome and thus diminished central/peripheral deposition ratio (C/P ratio). All measured lung function values except FEV1/FVC% improved after the medication period, although statistically significant levels were not reached. A systemic positive connection was seen between enhanced lung functions and greater lung deposition measured as AUC(0-24h)/24 Beclomethasone liposome formulation maintained its long-lasting effect in connection with formoterol treatment. At the 4-h measurement, 76% of the liposome-entrapped radioactivity still remained in the lungs before and 75% after the medication period.

Improvement of brain perfusion SPET using iterative reconstruction with scatter and non-uniform attenuation correction.

Filtered back-projection (FBP) is generally used as the reconstruction method for single-photon emission tomography although it produces noisy images with apparent streak artefacts. It is possible to improve the image quality by using an algorithm with iterative correction steps. The iterative reconstruction technique also has an additional benefit in that computation of attenuation correction can be included in the process. A commonly used iterative method, maximum-likelihood expectation maximisation (ML-EM), can be accelerated using ordered subsets (OS-EM). We have applied to the OS-EM algorithm a Bayesian one-step late correction method utilising median root prior (MRP). Methodological comparison was performed by means of measurements obtained with a brain perfusion phantom and using patient data. The aim of this work was to quantitate the accuracy of iterative reconstruction with scatter and non-uniform attenuation corrections and post-filtering in SPET brain perfusion imaging. SPET imaging was performed using a triple-head gamma camera with fan-beam collimators. Transmission and emission scans were acquired simultaneously. The brain phantom used was a high-resolution three-dimensional anthropomorphic JB003 phantom. Patient studies were performed in ten chronic pain syndrome patients. The images were reconstructed using conventional FBP and iterative OS-EM and MRP techniques including scatter and nonuniform attenuation corrections. Iterative reconstructions were individually post-filtered. The quantitative results obtained with the brain perfusion phantom were compared with the known actual contrast ratios. The calculated difference from the true values was largest with the FBP method; iteratively reconstructed images proved closer to the reality. Similar findings were obtained in the patient studies. The plain OS-EM method improved the contrast whereas in the case of the MRP technique the improvement in contrast was not so evident with post-filtering.

Emptying of the jejunal pouch and Roux-en-Y limb after total gastrectomy--a randomised, prospective study.

OBJECTIVE: To investigate the emptying of solids after total gastrectomy with pouch reconstruction. DESIGN: Randomised, prospective study. SETTING: University hospital, Finland. SUBJECTS: 49 patients with gastric carcinoma operated on for cure between 1988 and 1992. INTERVENTIONS: After total gastrectomy 26 patients were randomised to have a pouch reconstruction and 23 a Roux-en-Y reconstruction. 15 months after the operation 24 patients with a pouch (pouch group) and 21 patients with a simple Roux-en-Y reconstruction (Roux-en-Y group) were alive and available to have an emptying test by the solid isotope method. Emptying of the pouch and Roux-en-Y limb was assessed by measuring the activity at 3 hours. MAIN OUTCOME MEASURES: Postoperative symptoms, size of meal, and postoperative nutrition. RESULTS: Emptying was significantly slower after pouch reconstruction than after Roux-en-Y (mean activity at 3 hours 82% and 44%, respectively, p < 0.01). Early satiety occurred in 10 (48%) of the patients after Roux-en-Y reconstruction and 6 (25%) in the pouch group. Dumping was more common in the Roux-en-Y group (n = 12, 57% compared with n = 6, 25%, p = 0.04). 19 (79%) of the patients in the pouch group were able to eat normal sized meals compared with 3 (14%) in the Roux-en-Y group (p < 0.0001). Weight gain and haemoglobin and albumin concentrations were similar in the two groups. CONCLUSION: Jejunal pouch reconstruction after total gastrectomy delays passage of solid food in the upper intestine compared with Roux-en-Y reconstruction. It is associated with better eating capacity and fewer postoperative symptoms.

Pulmonary distribution and clearance of two beclomethasone liposome formulations in healthy volunteers.

The pulmonary distribution and clearance of 99mTc-labelled beclomethasone dipropionate (Bec) dilauroylphosphatidylcholine (DLPC) and dipalmitoylphosphatidylcholine (DPPC) liposomes were compared in 11 healthy volunteers using gamma scintigraphy. As delivered by using the Aerotech jet nebulizer both liposome aerosols had a suitable droplet size (mass median aerodynamic diameter 1.3 microm) allowing deep pulmonary deposition. However, in the total drug output during the inhalation there was a relatively large difference between DLPC and DPPC of 11.4 and 3.1 microg, respectively. In a gamma camera study no significant differences existed in the central/peripheral lung deposition between the DLPC and DPPC formulations. Progressive clearance of both Tc-labelled Bec liposomes was seen: 24 h after inhalation, 79% of the originally deposited radioactivity of DLPC liposomes and 83% of that of DPPC liposomes remained in the lungs. Thus there was slightly slower clearance of inhaled liposomes using DPPC instead of DLPC. We conclude that both liposome formulations are suitable for nebulization, although aerosol clouds were more efficiently made from the DLPC liposome suspension. Our results support the view that liposome encapsulation of a drug can offer sustained release and drug action in the lower airways.

Variables affecting quantitative biliary scintigraphy in asymptomatic cholecystectomized volunteers.

BACKGROUND/AIMS: Quantitative cholescintigraphy has been used to evaluate biliary emptying and, by some, as a screening test for sphincter of Oddi dyskinesia in cholecystectomized patients. Our aim was to identify variables that might effect the interpretation of the scintigraphy in asymptomatic cholecystectomized volunteers. METHODOLOGY: Quantitative cholescintigraphy was performed in 37 volunteer. There were 11 males and 26 females with a median age of 49 years (range: 32-82). The time interval from cholecystectomy ranged from 1 month to 30 years (median: 5 years). Eight subjects had also undergone choledocholithotomy during the cholecystectomy operation. RESULTS: From the time of the injection of the radioisotope to the maximum activity in the liver, the percentage of clearance and the hepatic hilum-duodenal transit time were measured to be 45 and 60 min, respectively. The maximum activity obtained in the liver was 17 +/- 10 min (mean +/- SD), and the percentage of clearance at 45 min was 52 +/- 22% and at 60 min 67 +/- 20%. Hilum-duodenal transit time was 12 +/- 11 min. The gender of the volunteer and previous choledocholithotomy did not correlate with the parameters studied. The age of the volunteer and the follow-up time had a positive correlation to the time of maximum activity and negative correlation to percentage of clearance. The follow-up time also had a positive correlation to hilum-duodenal transit time. In the multivariate analysis, the time interval since cholecystectomy was the only independent variable affecting study parameters. CONCLUSIONS: The length of the time interval since cholecystectomy but not the gender, age, or previous choledocholithotomy should be taken into consideration when the results of quantitative cholescintigraphy are interpreted.

Regional lung deposition and clearance of 99mTc-labeled beclomethasone-DLPC liposomes in mild and severe asthma.

OBJECTIVE: To compare the distribution and clearance of inhaled beclomethasone dipropionate (Bec)-dilauroylphosphatidylcholine (DLPC) liposomes in patients with mild and severe asthma. DESIGN: A 99mTc-labeled Bec-DLPC suspension was delivered via a nebulizer (Aerotech II). Immediately after inhalation, anterior and posterior views of the lungs and an anterior view of the oropharynx were measured by a large field gamma camera with the patient in a supine position. To evaluate the mucociliary clearance of the inhaled liposomes, anterior and posterior lung scans were repeated 1, 2, 4, and 24 h after the aerosol delivery. PATIENTS: Ten patients with mild asthma (FEV1 >80% of the predicted) and 10 patients with severe asthma (FEV1 <60% of the predicted) were included in an open, parallel group study. RESULTS: Clearance is more rapid among patients with severe asthma (p<0.0001). At the 4-h measurement, a mean of 82% (SD, 5.9) of the total pulmonary dose was detected in the lungs of patients with mild asthma while in those with severe asthma the figure was 69% (SD, 10.9). The ratio between central and peripheral deposition was significantly higher for patients with severe asthma than for those having a mild form of the disease; 1.07 (SD, 0.29) and 0.76 (SD, 0.07), respectively (p=0.008). CONCLUSIONS: Inhaled Bec-DLPC liposomes were deposited more centrally in the lower airways of patients with severe asthma than those having a milder form of the disease. The clearance of Bec-DLPC liposomes is strikingly slow in both groups of asthmatic patients. However, due to the more peripheral penetration of inhaled liposomes in patients with mild asthma, the clearance rate in this group was slower than in those with severe asthma.

Effect of fundal mobilisation in Nissen-Rossetti fundoplication on oesophageal transit and dysphagia. A prospective, randomised trial.

OBJECTIVE: To assess the effect on postoperative dysphagia and oesophageal transit of fundal mobilisation during Nissen-Rossetti fundoplication. DESIGN: Prospective, randomised study. SETTING: University Hospital, Finland. SUBJECTS: 20 consecutive patients with confirmed gastro-oesophageal reflux who were referred for antireflux surgery. INTERVENTIONS: Fundoplication with either conventional Nissen-Rossetti procedure or an otherwise identical technique incorporating total fundal mobilisation (n = 10 in each group). MAIN OUTCOME MEASURES: Recurrent or persistent symptoms of dysphagia, and the oesophageal transit time of a liquid bolus labelled with radioactive nuclide. RESULTS: In both groups excellent relief of heartburn and regurgitation was achieved (only 2 patients in each group reported occasional symptoms), one patient had oesophagitis, and the pH returned to the normal range. The incidence of dysphagia was similar in both groups by 6 months postoperatively, but there was significant, though transient, impairment of oesophageal transit after findal mobilisation (p = 0.03). CONCLUSIONS: Fundal mobilisation did not seem to confer any advantage as fas as the incidence of postoperative dysphagia was concerned. On the contrary, it was associated with transient disturbance in the oesophageal transit time of a liquid bolus. Longer follow up is needed to show if this impairment is of any clinical relevance.

QRS score as an indicator of myocardial viability after thrombolytic therapy.

Electrocardiographic estimation of myocardial injury has, in some studies, correlated poorly with the extent of nuclear perfusion defects at rest and with changes in the left ventricular ejection fraction after acute reperfusion therapy. The authors investigated 16 patients with fatty acid scintigraphy and with the Selvester-Wagner QRS score 2 weeks and 3 months after an anterior myocardial infarction. Segmental uptake on tomographic scans was semiquantitatively classified as low, moderate, or normal. The analysis included a total of 707 segments. QRS scores and the number of segments with low fatty acid uptake did not significantly change during the follow-up period, although the number of segments with moderate fatty acid uptake decreased from 15.9 +/- 5.1 to 12.4 +/- 5.7 (P < .05). The QRS score correlated significantly (rho = .56-.64) with low fatty acid uptake, but not with moderate fatty acid uptake. It is concluded that the QRS score is related to the degree of permanent myocardial injury, even after thrombolysis.

Refundoplication for recurrent gastroesophageal reflux.

Reoperation after a failed antireflux procedure is a surgical challenge. Many operative techniques have been proposed, but reports on systematic follow-up with endoscopy and esophageal function tests are few. The purpose of the present study was to evaluate the results of repeated fundoplication in cases of recurrent reflux, including assessment of esophageal function. Of the 18 cases of repeat fundoplication performed for recurrent reflux during 1970-1991 at Tampere University Hospital, 15 were evaluated a median of 18 (range 5-152) months after reoperation. Follow-up studies included endoscopy in all and esophageal function tests (esophageal 24-hour pH recording, manometry, and radionuclide transit) in 14 cases. All the patients had defective fundic wrap before reoperation, whereas at follow-up 12 of the 15 wraps were intact. Reflux symptoms were diminished in all 15. Six patients (40%), however, had objective recurrence of reflux (esophagitis or pathologic pH recording). Three of the recurrences were due to slipped fundic wrap, but the others were probably caused by impaired esophageal function. By repeat fundoplication the wrap could be repaired as reliably as in primary operation. Symptomatic outcome and objective results were reasonable. The results were, however, not as good as after primary operation, which was due to more impaired esophageal motility caused by prolonged reflux or repeated surgery (or both).

Inhaled budesonide fails to inhibit the PAF-induced increase in plasma leukotriene B4 in man.

1. We studied the ability of inhaled budesonide to modulate PAF-induced acute effects in nine healthy nonsmoking volunteers. Responses in inflammatory cells and mediators in peripheral blood as well as in pulmonary function and circulation were monitored. 2. Inhalation of increasing doses of PAF (total cumulative dose of 500 micrograms) caused a rapid and profound decrease in circulating white blood cells, especially in granulocytes (P less than 0.01), which was turned to an increased number of these cells (P less than 0.05, P less than 0.025, respectively) in the blood samples taken 8 min after completion of the PAF challenge. No changes in the circulating platelets or their thromboxane production were found. Plasma concentrations of histamine or methylhistamine remained unchanged during PAF-inhalation, while plasma LTB4 tripled from the baseline level at 10 min (P less than 0.0005) and was returned to the pre-PAF value at 60 min. 3. PAF inhalation induced a bronchial obstruction (P less than 0.025), but no bronchial hyperresponsiveness to methacholine was found in any of our subjects when measured 24 h after the PAF challenge. Furthermore, PAF caused a decrease in systolic blood pressure (P less than 0.05). 4. Budesonide pretreatment of 400 micrograms twice daily during the preceding 5 days had no effect on any PAF-induced events measured in our study. That fact may also contradict the role of bronchial resident or alveolar cells as a source of the PAF-induced LTB4 burst in plasma. 5. We conclude that in healthy volunteers inhaled PAF induces a marked increase in plasma LTB4, which is not inhibited by inhaled budesonide.(ABSTRACT TRUNCATED AT 250 WORDS)

Platelet-activating factor impairs mucociliary transport and increases plasma leukotriene B4 in man.

We assessed the effect of inhaled platelet-activating factor (PAF) on tracheobronchial clearance, pulmonary function and blood pressure in seven healthy volunteers. After inhalation of 500 micrograms of PAF, retention of radioaerosol in ciliated airways measured at 4 h was 80% higher than in the control recording, and the clearance was reduced by 33% (p less than 0.005). Acetylsalicylic acid (ASA) did not abolish the phenomenon. PAF also decreased forced expiratory volume in one second (FEV1) by 16% (p less than 0.01), which was markedly attenuated by acetylsalicylic acid. The decrease in blood pressure after PAF (p less than 0.01) was not influenced by acetylsalicylic acid. Plasma leukotriene B4 (LTB4) was increased at 20 min after PAF inhalation (without and with ASA: mean 240 and 299 pg.ml.1, respectively) as compared to the baseline (144 and 166 pg.ml.1) and the values at 60 min after the challenge (133 and 178 pg.ml.1; p less than 0.05 and p less than 0.01, respectively). Only three out of seven subjects showed a bronchial hyperresponsiveness to methacholine measured 24 h after PAF. The PAF-induced reduction of mucociliary transport seems to be independent of cyclo-oxygenase products of arachidonic acid metabolism. These autacoids are, however, believed to contribute to the acute bronchial obstruction after PAF inhalation. In addition, inhaled PAF causes a transient increase in plasma LTB4.

Duodenogastrocolic reflux after colonic interposition measurement using scintigraphic method.

Enterogastric reflux was studied using the scintigraphic method in 20 patients with colonic interposition for benign esophageal disease. The state of the transplanted colonic mucosa was evaluated by endoscopy. In 16 patients, reflux of the duodenal contents into the stomach could be seen. In eight, reflux of the duodenal contents into the interposed colon could be demonstrated. There were no differences in the occurrence of reflux into the colonic graft between the isoperistaltic and antiperistaltic interpositions. In three patients, signs of colitis on the mucosa on the lower part of the graft were observed by endoscopy. Each of these patients had a reflux of the duodenal contents into the colonic graft. In monitoring the 24 hour pH of these three patients, one patient had marked acid reflux. Alkaline reflux was not observed. It is concluded that enterogastric reflux is frequent in patients with colonic interposition. Its role in the development of lower colonic graft colitis changes is discussed.

Radionuclide transit in patients with colon interposition.

To assess radionuclide transit in interposed segments of the colon, we examined 25 patients with colon interposition for benign esophageal disease. No such assessment has been reported previously. The most common indications for operation were esophageal strictures that developed after lye ingestion and reflux strictures not responding to other treatment. The operations were performed without thoracotomy by blunt esophageal dissection in 80% of the patients. There were 18 antiperistaltic and seven isoperistaltic colon grafts. A large-field gamma camera and computer system were used. Data were collected at time intervals of 0.5 second during the first 30 seconds and at intervals of 30 seconds up to 20 minutes. The 5% and 90% stomach filling times, times to 50% and 25% activity levels, and residual activity levels as a percentage of the maxima were calculated in the upper, middle, and lower thirds of the colon grafts and of the normal esophagus of 10 healthy control subjects. The examinations were performed with the subject in a sitting position. All parameters showed that emptying of the colon graft was markedly slower than that of the normal esophagus. The intra-abdominal third of the graft had a residual activity of 50.5% +/- 15.7% after 20 minutes' observation. No differences between antiperistaltic and isoperistaltic grafts were observed. Reconstruction with proximal cologastric anastomosis and a short intra-abdominal colon graft segments is suggested.