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author:("valine, Sven")
1.  Adding attenuation corrected images in myocardial perfusion imaging reduces the need for a rest study 
BMC Medical Imaging  2013;13:14.
The American Society of Nuclear Cardiology and the Society of Nuclear Medicine conclude that incorporation of attenuation corrected (AC) images in myocardial perfusion scintigraphy (MPS) will improve diagnostic accuracy. The aim was to investigate the value of adding AC stress-only images for the decision whether a rest study is necessary or not.
1,261 patients admitted to 99mTc MPS were studied. The stress studies were interpreted by two physicians who judged each study as “no rest study necessary” or “rest study necessary”, by evaluating NC stress-only and NC + AC stress-only images. When there was disagreement between the two physicians, a third physician evaluated the studies. Thus, agreement between 2 out of 3 physicians was evaluated.
The physicians assessed 214 more NC + AC images than NC images as “no rest study necessary” (17% of the study population). The number of no-rest-study-required was significantly higher for NC + AC studies compared to NC studies (859 vs 645 cases (p < 0.0001). In the final report according to clinical routine, ischemia or infarction was reported in 23 patients, assessed as “no rest study necessary” (22 NC + AC cases; 8 NC cases), (no statistically significant difference). In 11 of these, the final report stated “suspected/possible ischemia or infarction in a small area”.
Adding AC stress-only images to NC stress-only images reduce the number of unnecessary rest studies substantially.
PMCID: PMC3618204  PMID: 23547878
Tc99m MPS; Ischemic cardiac disease; Attenuation correction; Stress-only studies
2.  Nuclear medicine technologists are able to accurately determine when a myocardial perfusion rest study is necessary 
In myocardial perfusion scintigraphy (MPS), typically a stress and a rest study is performed. If the stress study is considered normal, there is no need for a subsequent rest study. The aim of the study was to determine whether nuclear medicine technologists are able to assess the necessity of a rest study.
Gated MPS using a 2-day 99mTc protocol for 121 consecutive patients were studied. Visual interpretation by 3 physicians was used as gold standard for determining the need for a rest study based on the stress images. All nuclear medicine technologists performing MPS had to review 82 training cases of stress MPS images with comments regarding the need for rest studies, and thereafter a test consisting of 20 stress MPS images. After passing this test, the nuclear medicine technologists in charge of a stress MPS study assessed whether a rest study was needed or not or if he/she was uncertain and wanted to consult a physician. After that, the physician in charge interpreted the images and decided whether a rest study was required or not.
The nuclear medicine technologists and the physicians in clinical routine agreed in 103 of the 107 cases (96%) for which the technologists felt certain regarding the need for a rest study. In the remaining 14 cases the technologists were uncertain, i.e. wanted to consult a physician. The agreement between the technologists and the physicians in clinical routine was very good, resulting in a kappa value of 0.92. There was no statistically significant difference in the evaluations made by technicians and physicians (P = 0.617).
The nuclear medicine technologists were able to accurately determine whether a rest study was necessary. There was very good agreement between nuclear medicine technologists and physicians in the assessment of the need for a rest study. If the technologists can make this decision, the effectiveness of the nuclear medicine department will improve.
PMCID: PMC3457849  PMID: 22947251
Image interpretation; Radionuclide imaging; Ischemic heart disease; 99Tc MPS
3.  Semi-automatic analysis of standard uptake values in serial PET/CT studies in patients with lung cancer and lymphoma 
BMC Medical Imaging  2012;12:6.
Changes in maximum standardised uptake values (SUVmax) between serial PET/CT studies are used to determine disease progression or regression in oncologic patients. To measure these changes manually can be time consuming in a clinical routine. A semi-automatic method for calculation of SUVmax in serial PET/CT studies was developed and compared to a conventional manual method. The semi-automatic method first aligns the serial PET/CT studies based on the CT images. Thereafter, the reader selects an abnormal lesion in one of the PET studies. After this manual step, the program automatically detects the corresponding lesion in the other PET study, segments the two lesions and calculates the SUVmax in both studies as well as the difference between the SUVmax values. The results of the semi-automatic analysis were compared to that of a manual SUVmax analysis using a Philips PET/CT workstation. Three readers did the SUVmax readings in both methods. Sixteen patients with lung cancer or lymphoma who had undergone two PET/CT studies were included. There were a total of 26 lesions.
Linear regression analysis of changes in SUVmax show that intercepts and slopes are close to the line of identity for all readers (reader 1: intercept = 1.02, R2 = 0.96; reader 2: intercept = 0.97, R2 = 0.98; reader 3: intercept = 0.99, R2 = 0.98). Manual and semi-automatic method agreed in all cases whether SUVmax had increased or decreased between the serial studies. The average time to measure SUVmax changes in two serial PET/CT examinations was four to five times longer for the manual method compared to the semi-automatic method for all readers (reader 1: 53.7 vs. 10.5 s; reader 2: 27.3 vs. 6.9 s; reader 3: 47.5 vs. 9.5 s; p < 0.001 for all).
Good agreement was shown in assessment of SUVmax changes between manual and semi-automatic method. The semi-automatic analysis was four to five times faster to perform than the manual analysis. These findings show the feasibility of using semi-automatic methods for calculation of SUVmax in clinical routine and encourage further development of programs using this type of methods.
PMCID: PMC3350379  PMID: 22471689
Image analysis; Radionuclide imaging; Quantification
4.  Right ventricular metastasis of leiomyosarcoma 
Metastatic presentation of leiomyosarcoma in the heart is very rare. We present transthoracic echocardiography and combined PET/CT images of a case with a large right ventricular metastasis of leiomyosarcoma. The patient was placed on cytostatic drugs for palliative purposes, but passed away one month later because of an untreatable ventricular tackycardia.
PMCID: PMC2685770  PMID: 19416508
5.  Primary lung tumour visualised by transthoracic echocardiography 
We present images of a rare case where a primary lung tumour was visualised by transthoracic echocardiography. The patient was a 78-year-old male where Chest X-ray had revealed a tumour-suspected structure in the left lung. Both transthoracic echocardiography and combined PET/CT images showed a large tumour located close to the heart. Fine-needle biopsy showed non-small cell lung cancer.
PMCID: PMC2614958  PMID: 19087342

Results 1-5 (5)