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"Radionuclide Imaging - statistics "
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Risk Assessment of Posthepatectomy Liver Failure Using Hepatobiliary Scintigraphy and CT Volumetry
by
van Lienden, Krijn P
,
van Gulik, Thomas M
,
Gouma, Dirk J
in
Adult
,
Aged
,
Biliary Tract - diagnostic imaging
2007
A major part of morbidity and mortality after liver resections is caused by inadequate remnant liver function leading to liver failure. It is therefore important to develop accurate diagnostic tools that can predict the risk of liver resection-related morbidity and mortality. In this study, preoperative hepatobiliary scintigraphy of the future remnant liver and CT volumetric measurement of the future remnant liver were performed on patients who were to undergo liver resection. The accuracy of risk assessment for postoperative morbidity, liver failure, and mortality was evaluated.
Forty-six patients who were scheduled for liver resection because of hepatobiliary tumors, including 17 patients with parenchymal disease (37%) and 13 patients with hilar cholangiocarcinoma (28%), were assessed preoperatively. Hepatobiliary scintigraphy was performed by drawing regions of interest around the future remnant to calculate (99m)Tc-mebrofenin uptake in it. CT volumetry was used to measure the volume of the total liver, the tumors, and the future remnant. Receiver-operating-characteristic analysis was performed to assess cutoff values for risk assessment of morbidity, liver failure, and mortality. Furthermore, univariate and multivariate analyses were performed to determine factors related to morbidity and mortality.
Morbidity and mortality rates were 61% and 11%, respectively. Liver failure occurred in 6 patients (13%). Significantly decreased uptake in the future remnant was found in patients in whom liver failure and liver failure-related mortality developed (P=0.003 and 0.02, respectively). The volume of the future remnant was not significantly associated with any of the outcome parameters. In receiver-operating-characteristic analysis, uptake cutoff values for liver failure and liver failure-related mortality were 2.5%/min/body surface area and 2.2%/min/body surface area, respectively. In multivariate analysis, uptake was the only significant factor associated with liver failure.
Preoperative measurement of (99m)Tc-mebrofenin uptake in the future remnant liver on hepatobiliary scintigraphy proved more valuable than measurement of the volume of the future remnant on CT in assessing the risk of liver failure and liver failure-related mortality after partial liver resection.
Journal Article
Exposure to Low-Dose Ionizing Radiation from Medical Imaging Procedures
by
Krumholz, Harlan M
,
Shah, Nilay D
,
Fazel, Reza
in
Adolescent
,
Adult
,
Biological and medical sciences
2009
The use of medical imaging procedures has been increasing, and this study estimated the exposure of U.S. patients to low-dose ionizing radiation from these procedures. The exposure was substantial, largely because of radiation from computed tomography and nuclear imaging. The highest average effective dose was attributable to myocardial perfusion imaging, and most imaging occurred in outpatient settings. These data indicate that the use of imaging can result in high radiation doses.
This study estimated the exposure of U.S. patients to low-dose ionizing radiation from medical imaging procedures. The exposure was substantial, largely because of radiation from computed tomography and nuclear imaging.
Experimental and epidemiologic evidence has linked exposure to low-dose, ionizing radiation with the development of solid cancers and leukemia.
1
As a result, persons at risk for repeated radiation exposure, such as workers in health care and the nuclear industry, are typically monitored and restricted to effective doses of 100 mSv every 5 years (i.e., 20 mSv per year), with a maximum of 50 mSv allowed in any given year.
2
,
3
In contrast, radiation exposure in patients who undergo medical imaging procedures is not typically monitored, and patient data on longitudinal radiation exposure from these procedures are scant, even though in . . .
Journal Article
Pre-operative Localisation of the Parathyroid Glands in Secondary Hyperparathyroidism: A Retrospective Cohort Study
by
Toshihiro Ichimori
,
Yoshihiko Watarai
,
Toshihide Tomosugi
in
692/163/2743/1717
,
692/698/1460/418
,
Adult
2019
Complete parathyroidectomy (PTx) is essential during total PTx for secondary hyperparathyroidism (SHPT) to prevent recurrent and persistent hyperparathyroidism. Pre-operative imaging evaluations, including computed tomography (CT), ultrasonography (US), and Tc-99m sestamibi (MIBI) scans, are commonly performed. Between June 2009 and January 2016, 291 patients underwent PTx for SHPT after pre-operative evaluations involving CT, US, and MIBI scans, and the diagnostic accuracies of these imaging modalities for identifying the parathyroid glands were evaluated in 177 patients whose intact parathyroid hormone (PTH) levels were <9 pg/mL after the initial PTx. Additional PTx procedures were performed on 7 of 114 patients whose intact PTH levels were >9 ng/mL after PTx, and the diagnostic validities of the imaging modalities for the remnant parathyroid glands were evaluated. A combination of CT, US, and MIBI scans achieved the highest diagnostic accuracy (75%) for locating bilateral upper and lower parathyroid glands before initial PTx. The accuracies of CT, US, and MIBI scans with respect to locating remnant parathyroid glands before additional PTx were 100%, 28.6%, and 100%, respectively. A combination of CT, US, and MIBI scans is useful for initial PTx for SHPT, and CT and MIBI scans are useful imaging modalities for additional PTx procedures.
Journal Article
Re-operative parathyroidectomy: How many positive localization studies are required?
by
Ramonell, Kimberly M.
,
Fazendin, Jessica
,
Lindeman, Brenessa
in
Endocrine surgery
,
Endocrine system
,
Female
2021
Re-operative parathyroidectomy in patients with recurrent or persistent hyperparathyroidism can be challenging. We review our experience to determine the optimal number of localization studies prior to re-operation.
From 2001 to 2019, 251 patients underwent re-operative parathyroidectomy. Parathyroidectomies were stratified to 4 groups based upon the number of positive localization studies obtained: A) ZERO, B) 1-positive, C) 2-positive, D) 3-positive.
The overall cure rate was 97%, where 201 single gland resections, 23 two-gland resections, 22 subtotal/total, and 5 forearm autograft resections were performed. Thirty-two patients had no positive studies (A), 172 patients had 1-positive (B), 42 patients had 2-positive (C), and 5 patients had 3-positive studies (D). There was no difference in surgical cure rates between groups (p = 0.71). The majority of patients had one or no positive imaging studies yet almost all still achieved cure.
Successful re-operative parathyroidectomy can be performed with minimal pre-operative scans in certain clinical contexts.
•Optimal number of localization studies needed prior to re-operative parathyroidectomy is unknown in the contemporary era.•Patients with recurrent or persistent hyperparathyroidism had similar outcomes regardless of localization studies.•The majority of patients had one or no positive parathyroid imaging studies yet almost all still achieved cure.•In certain patients, successful re-operative parathyroidectomy can be performed with minimal pre-operative scans.
Journal Article
Gastric Peroral Endoscopic Myotomy (G-POEM) as a Treatment for Refractory Gastroparesis: Long-Term Outcomes
by
Chen, Tianyin
,
Xu, Jiaxin
,
Zhou, Pinghong
in
Botulinum toxin
,
Care and treatment
,
Clinical Study
2018
Background and Aims. Gastric peroral endoscopic myotomy (G-POEM) has been regarded as a novel and minimally invasive therapy for refractory gastroparesis. This study reports the long-term outcomes and possible predictive factors for successful outcomes after G-POEM in an Asian population. Methods. This is a retrospective single-centre study of 16 patients who underwent G-POEM for refractory gastroparesis from August 2016 to October 2017. This study included 11 males and 5 females; in addition, 13 patients had postsurgical gastroparesis, and 3 patients had diabetes. The patients included had severe and refractory gastroparesis, as indicated by a Gastroparesis Cardinal Symptom Index (GCSI) score ≥20, and evidence of a delay on gastric emptying scintigraphy (GES). The primary outcome parameter was an assessment of the long-term clinical efficacy of the procedure. The secondary outcome parameter was the detection of possible predictive factors for success and the determination of cut-off values for such predictors. Results. Technical success was achieved in 100% of the patients, with a mean procedure time of 45.25±12.96 min. The long-term clinical response was assessed in all patients during a median follow-up of 14.5 months. Clinical success was achieved in 13 (81.25%) patients. There was a significant reduction in the GCSI scores and GES values after the procedure compared to the baseline values, with P values of <0.0001 and 0.012, respectively. Univariate regression analysis showed that the GCSI and GES had significant associations with the future clinical outcomes of the patients, but this finding was not confirmed in multivariate analysis. A GCSI cut-off score of ≤30 had a high sensitivity and a negative predictive value (NPV) of 100% for predicting a successful procedure. GES (half emptying time ≤221.6 min and 2-hour retention ≤78.6%) had a high specificity and a positive predictive value (PPV) of 100%. Conclusions. G-POEM is a safe and effective treatment option with a long-term efficacy of 81.6%. GCSI and GES could serve as good predictive measures.
Journal Article
Practice Patterns in Parathyroid Surgery: A Survey of Asia-Pacific Parathyroid Surgeons
by
Chen, Rufi
,
Gorelik, Alexandra
,
Oh, Han Boon
in
Abdominal Surgery
,
Asia, Eastern
,
Asia, Southeastern
2019
Background
Practice variations exist amongst parathyroid surgeons depending on their expertise and resources. Our study aims to elucidate the choice of surgical techniques and adjuncts used in parathyroid surgery by surgeons in the Asia-Pacific region.
Methods
A 25-question online survey was sent to members of five endocrine surgery associations. Questions covered training background, practice environment and preferred techniques in parathyroid surgery. Respondents were divided into three regions: Australia/New Zealand, South/South East Asia and East Asia, and responses were analysed according to region, specialty, case volume and years in practice.
Results
One hundred ninety-six surgeons returned the questionnaire. Most surgeons (98%) routinely perform preoperative imaging, with 75% preferring dual imaging with
99m
Tcsestamibi and ultrasound. Ten per cent of surgeons use parathyroid 4DCT as first-line imaging, more commonly in East Asia (
p
= 0.038). Minimally invasive parathyroidectomy is the favoured technique of choice (97%). Most surgeons reporting robotic or endoscopic approaches are from East Asia. Rapid intraoperative parathyroid hormone is accessible to just under half of the surgeons but less available in Australian/New Zealand (
p
< 0.001). The use of intraoperative neuromonitoring is not commonly used, even less so amongst Asian surgeons (
p
= 0.048) and surgeons with low case load (
p
= 0.013).
Conclusion
Dual localisation techniques are the preferred choice of investigations in preparation for parathyroid surgery, with minimally invasive surgery without neuromonitoring the preferred approach. Use of adjuncts is sporadic and limited to certain centres.
Journal Article
Comparison of the current reasons for undergoing pharmacologic stress during echocardiographic and radionuclide stress testing
2017
Symptom-limited exercise is the preferred method of cardiac stress testing, but pharmacologic testing has been increasing over time. The exact reasons for pharmacologic stress testing have not been rigorously categorized. Thus, we systematically explored the reasons for pharmacologic stress testing in patients referred for cardiac stress imaging.
We studied consecutive patients referred for stress imaging [stress echocardiography or radionuclide myocardial perfusion imaging (MPI)] at Mount Sinai St Luke’s hospital between August 2013 and April 2014. Baseline information was obtained using a standardized questionnaire and a trained physician triaged the patient for symptom-limited exercise stress testing or pharmacologic stress testing.
In total, 551(48%) of our entire stress cohort underwent cardiac imaging following initial exercise testing and 589 (52%) underwent imaging with initial pharmacologic stress testing. Deconditioning and inability to walk (primarily due to musculoskeletal conditions) constituted the top two reasons for performing pharmacologic stress, followed by frailty, left bundle branch block (for MPI), resting wall motion abnormality (for echocardiography), and failed exercise attempts. The reasons for performing pharmacologic stress testing were similar in the MPI and echocardiography patients, despite a much higher level of disease acuity in the MPI group.
We have applied a systematic approach for categorizing the reasons for pharmacologic stress. These reasons are heterogeneous, but similar across MPI and echo stress laboratories.
Journal Article
A National Study of the Use of Asymptomatic Systemic Imaging for Surveillance Following Breast Cancer Treatment (AFT-01)
by
Schumacher, Jessica R
,
Kozower, Benjamin D
,
Chang, George J
in
Bone cancer
,
Bone imaging
,
Breast cancer
2018
BackgroundAlthough not guideline recommended, studies suggest 50% of locoregional breast cancer patients undergo systemic imaging during follow-up, prompting its inclusion as a Choosing Wisely measure of potential overuse. Most studies rely on administrative data that cannot delineate scan intent (prompted by signs/symptoms vs. asymptomatic surveillance). This is a critical gap as intent is the only way to distinguish overuse from appropriate care.ObjectiveOur aim was to assess surveillance systemic imaging post-breast cancer treatment in a national sample accounting for scan intent.MethodsA stage-stratified random sample of 10 women with stage II–III breast cancer in 2006–2007 was selected from each of 1217 Commission on Cancer-accredited facilities, for a total of 10,838 patients. Registrars abstracted scan type (computed tomography [CT], non-breast magnetic resonance imaging, bone scan, positron emission tomography/CT) and intent (cancer-related vs. not, asymptomatic surveillance vs. not) from medical records for 5 years post-diagnosis. Data were merged with each patient’s corresponding National Cancer Database record, containing sociodemographic and tumor/treatment information.ResultsOf 10,838 women, 30% had one or more, and 12% had two or more, systemic surveillance scans during a 4-year follow-up period. Patients were more likely to receive surveillance imaging in the first follow-up year (lower proportions during subsequent years) and if they had estrogen receptor/progesterone receptor-negative tumors.ConclusionsLocoregional breast cancer patients undergo asymptomatic systemic imaging during follow-up despite guidelines recommending against it, but at lower rates than previously reported. Providers appear to use factors that confer increased recurrence risk to tailor decisions about systemic surveillance imaging, perhaps reflecting limitations of data on which current guidelines are based.ClinicalTrials.gov Identifier: NCT02171078.
Journal Article
Accuracy of hepatobiliary scintigraphy for differentiation of neonatal hepatitis from biliary atresia: systematic review and meta-analysis of the literature
by
Kakhki, Vahid Reza Dabbagh
,
Tehranian, Shahrzad
,
Sadeghi, Ramin
in
Biliary Atresia - diagnostic imaging
,
Causality
,
Cholestasis - diagnostic imaging
2013
Hepatobiliary scintigraphy is an important diagnostic modality for work-up of neonatal cholestasis. Therefore, our objective was to evaluate the literature regarding the accuracy of hepatobiliary scintigraphy in differentiating biliary atresia from non-biliary atresia causes of cholestasis (collectively called neonatal hepatitis). Our search included Medline, SCOPUS and Google Scholar. Only studies using Tc-99 m-labeled immunodiacetic acid (IDA) derivatives were included. Overall, 81 studies were included in the meta-analysis. Pooled sensitivity and specificity were 98.7% (range 98.1–99.2%) and 70.4% (range 68.5–72.2%), respectively. Factors that increased specificity included the use of radiotracers with high hepatic extraction, administration of hepatic-inducing drugs (such as phenobarbital), use of a calculated dose/kg and administration of a booster dose in cases of non-excretion of the tracer in the bowel. SPECT imaging and duodenal fluid sampling also had high specificity; however, they need further validation because of the low number of studies. Semiquantitative imaging methods do not seem to have any incremental value. We conclude that hepatobiliary scintigraphy using IDA derivatives can be very useful for diagnostic work-up of neonatal cholestasis. To improve the specificity, several measures can be followed regarding type and dose of the radiotracer and imaging protocols. Non-imaging methods seem to be promising and warrant further validation.
Journal Article
Determinants of left ventricular mechanical dyssynchrony in patients submitted to myocardial perfusion imaging: A cardiac CZT study
by
Marzullo, Paolo
,
Gimelli, Alessia
,
Favilli, Brunella
in
Aged
,
Cadmium
,
cadmium-zinc-telluride
2016
An interaction between coronary anatomy, myocardial perfusion, and left ventricular (LV) functional parameters in the development of mechanical LV dyssynchrony (LVD) has been suggested. This study examined the correlates of LVD in a large sample size of patients with known or suspected coronary artery disease (CAD) using cadmium-zinc-telluride camera.
Six-hundred and fifty-seven consecutive patients who underwent myocardial perfusion imaging (MPI) and coronary angiography were included. Coronary stenosis >70% was considered significant. LV perfusion and functional parameters were computed from MPI images. The presence of significant LVD was evaluated by phase standard deviation and histogram bandwidth.
415/657 (63%) patients had significant CAD. LVD was present in 247 (38%) patients and was associated with the presence of a higher CAD burden (P < .001), more impaired measures of LV perfusion (P < .001), contractile function (P < .001), and larger LV volumes (P < .001). By multivariate analysis, the LV end-systolic volume index (P < .001) and ischemic burden (P < .001) were the strongest predictors of LVD independent of CAD extent and LV systolic dysfunction.
LVD is frequent in patients undergoing MPI for suspected or known CAD. Its presence is independent of CAD burden and LV systolic dysfunction, but is dependent on the presence of myocardial perfusion abnormalities and LV end-systolic volume.
Journal Article