Introduction: A dipyridamole induced stress myocardial perfusion scintigraphy with Tc-99m Sestamibi is utilized for diagnosing coronary artery diseases. The use of dipyridamole as form of pharmacologic stressor has expected hemodynamic changes. Objective: The objective of this study was to determine the association of these changes with the scan parameters in patients with suspected coronary artery disease (CAD). Methodology: A total of 101 patients, with suspected CAD, who underwent a dipyridamole-induced stress myocardial perfusion scintigraphy using Tc-99m Sestamibi from January 2019 to March 2020 were included in this study. The patient databases, monitoring sheets, and scan results were reviewed . Results: The blood pressure responses had no significant association with the scan parameters and results. The normal (> 1.2) and abnormal (<1.2) heart rate ratios (HRR), which is the peak HR/baseline HR, likewise had no significant association with the scan results. However, in terms of the median HRR, the higher ratio of 1.29 (normal scan results) against the ratio of 1.25 (abnormal scan results) was determined to be significant (p-value of 0.032). The HRR also had a direct and indirect weak correlation with stress and rest Left Ventricular Ejection Fraction (LVEF) values (p-values of 0.09 and 0.011) and Summed Rest Score (p-value of 0.007), respectively. For the 12-L ECG, only the baseline normal (P-value of 0.018) and infarct findings (p-value of 0.017) were similarly associated with normal and abnormal scan results, respectively. Conclusion For patients with suspected CAD, the higher HRRs and baseline 12-L ECG of normal and infarct findings relates to the expected scan result. For scan parameters, the higher HRRs were also correlated with higher stress and rest LVEF values, and normal SRS, albeit a weak correlation. Notably, the blood pressure and post-infusion 12-L ECG changes had no significant association. In summary, the higher HRRs indicates normal scan results, normal SRS, and better LVEF values which increases the diagnostic confidence in the interpretation and management, especially in some equivocal cases.
Dipyridamole ; Myocardial perfusion scintigraphy

Objective: Phenobarbital is an inductor of microsomal hepatic enzyme and used as choleretic for cholestatic liver disease to enhance bile flow. It is also used as a premedication for hepatobiliary scintigraphy (HIDA) scan to improve diagnostic accuracy for an obstructive liver disease. We reviewed the available literature on the use of Phenobarbital for treatment of cholestasis and its utility as a premedication for HIDA scan. Methods: All published studies before June 30, 2023 that investigated the efficacy, effectiveness or safety of Phenobarbital in cholestatic jaundice and its effect on the accuracy of hepatobiliary scintigraphy in diagnosis of obstructive jaundice were included. Electronic databases were searched including MEDLINE via PubMed, Cochrane Library, medRxIV, BioRxIV, as well as the following registries for ongoing and completed trials: ClinicalTrials.gov (USA); ChiCTR.org. (China); and the WHO International Clinical Trials Registry Platform. We screened abstracts, reviewed full texts, and extracted relevant information on study design, settings, population and outcomes. There was no age and language restriction. Two reviewers independently rated the quality of included studies using: Joanna Briggs Institute critical appraisal tool for case reports, case series, and diagnostic accuracy; Newcastle – Ottawa Quality Assessment Scale for cohort studies, and Cochrane Risk of Bias for Randomized Trials. Risk of bias was appraised and GRADE certainty of evidence was judged. Pooled analysis was done using Stata 14 and reported as sensitivity and specificity. Results: Included were nine reports on Phenobarbital as treatment for cholestasis (one case report, five case series, one cohort and two randomized studies) and seven studies (four diagnostics, two cohorts, one randomized trial) on its use as a premedication for HIDA scan. The quality of case report and case series were considered fair; cohort studies as good; and diagnostic studies were included based on overall assessment. The randomized studies had some or high risk for bias due to concerns in randomization process, measurement of outcome, and risk in the selection of reported results. There were 31 patients (16 adults and 15 children) from case reports and case series. Of the 16 adults, serum total bilirubin concentrations declined from 4 to 70% from baseline in 13 of 15 (87%) patients after Phenobarbital was given at 120 to 250 mg per day from 22 days to f ive months. Eleven of 14 with pruritus at onset also had improvement in intensity of itching. Of the 15 pediatric patients, ten (67%) showed a decrease from 10 to 60% of the baseline total bilirubin but not a normalization with Phenobarbital intake at a dose of 3 to 12 mg/kg/day from one to 21 months. Five of 14 children also had relief of itching after treatment. Phenobarbital compared to Ursodeoxycholic acid had limited efficacy in reducing the bilirubin levels in neonates and young infants with cholestasis. Phenobarbital compared to Ursodeoxycholic acid had limited efficacy in reducing the bilirubin levels in neonates and young infants with cholestasis. Moderate certainty evidence showed that with Phenobarbital pretreatment, the hepatobiliary scan done on patients with neonatal cholestasis had 100% (CI 99.2, 100; I2 = 0.0%) sensitivity and 80.2% (CI 65.4, 92.1; I2 = 76.6%) specificity while no Phenobarbital pretreatment had 100% (94.9, 100; I2 = 0.0%) sensitivity and 89.5% (CI 77.0, 98.1; I2 = 11.4%) specificity. Adverse effects of Phenobarbital were drowsiness, lethargy, poor feeding, and irritability. Conclusion There was limited effectiveness of Phenobarbital in decreasing bilirubin levels in cholestatic liver disease. Moderate certainty evidence demonstrated that premedication with Phenobarbital did not improve the specificity of HIDA scan in the diagnosis of obstructive jaundice of infancy. Neurologic symptoms were observed with Phenobarbital intake.
phenobarbital ; cholestasis ; scintigraphy ; radionuclide imaging ; pruritus

Congenital cystic adenomatoid malformation is a rare bronchopulmonary malformation resulting from an arrest in lung development between 4th and 7th week of fetal life. It typically presents as respiratory distress in the neonatal period and recurrent pulmonary infections in adults; and is sometimes associated with other congenital abnormalities [especially CCAM Type II]. Chest roentgenograms and CT scan are the usual modalities of choice in its initial evaluation and histopathology done post-operatively establishes the diagnosis. Ventilation-Perfusion [VQ] scintigraphy is of paramount importance in the routine assessment of CCAM patients but is often disregarded. This paper presents the incremental value of doing a lung perfusion scintigraphy and aims to emphasize the significance of performing a VQ scan in such cases.
Human ; Female ; Adult ; RADIONUCLIDE IMAGING ; SCINTIGRAPHY ; DIAGNOSTIC IMAGING ; CYSTIC ADENOMATOID MALFORMATION OF LUNG, CONGENITAL ; CONGENITAL CYSTIC ADENOMATOID MALFORMATION OF LUNG ; LUNG DISEASES ; TOMOGRAPHY SCANNERS, X-RAY COMPUTED

Nuclear medicine departments use the camera-based method for determining glomerular filtration rate (GFR) with 99mTc-DPTA. Camera based techniques provide a fast and convenient way of determining GFR with excellent reproducubility however its accuracy remains in question. The accuracy of camera-based renal scintigraphy depends on an attenuation correlation from estimating for renal depth and an attenuation correction from estimating for renal depth and an attenuation coefficient. Algorithms were formulated by Tonnesen, Taylor, and Inoue to calculate the estimated renal depth through multiple stepwise linear regression analysis. The goal of this study was to analyze the accuracy of these algorithms in Filipino patients. Renal depth was determined from CT scans of 41 consecutive patients. We calculated the mean absolute error of the estimated kidney depths and compared them with each other to determine the accuracy of each algorithm. The Tonnesen algorithm had the highest mean absolute error of 1.25 cm plus minus 0.88 cm in the left kidney estimates while the Taylor algorithm had the lowest mean absolute error of 0.81 cm plus minus 0.58 cm in the left kidney estimate and 1.04 cm plus minus 0.82 cm in the right kidney estimate (p-value = 0.01 left kidney estimates and p-value = 0.02 right kidney estimates). The Tonnesen algorithm was the least accurate in predicting kidney depth. There was no significant difference between the Taylor and Inoue algorithms, which were more accurate in predicting kidney depth
Human ; Male ; Female ; KIDNEY ; UROGENITAL SYSTEM ; URINARY TRACT ; GLOMERULAR FILTRATION RATE ; DIAGNOSIS ; DIAGNOSTIC TECHNIQUES AND PROCEDURES ; DIAGNOSTIC TECHNIQUES, UROLOGICAL ; KIDNEY FUNCTION TESTS ; RENAL SCINTIGRAPHY

The study aims to determine the relationship of body mass index (BMI) and related anthropometric measurements on the image quality of Tl-201 and Tc-99m sestamibi myocardial perfusion scans (MPS). A total of 163 scans were analyzed. A blinded experienced physician performed visual analysis on the scans image quality on two different occasions. Quantitative parameter used was the heart-to-lung ratio (HLR). Regression analysis was done to determine the association of HLR with BMI and myocardial tracer uptake, ROC curves were generated to establish BMI and HLR cut-off points. Increasing BMI was associated with visually poorer images in the Tl-201 MPS group (p 0.003) but not for the Tc-99m MPS group (p 0.065). It was also associated with decrease HLR and myocardial tracer upatake for both tracers (p <0.001). ROC curves revealed BMI cut-off points of 28 (Tl-201 p 0.000; Tc99m sestamibi p 0.004) for both procedures; HR cut-off values of 3.0 for Tl-201 )p 0.295) and 2.5 for Tc-99m sestamibi (p 0.875). the image quality of Tl-201 scans begins to deteriorate at a BMI of 28 and HLR of 3.0 with myocardial count density reduction (less than or equal to 6000 counts) translating to visually poorer images. On the other hand , image quality of Tc-99m sestamibi scans also tend to deteriorate similarly at a BMI of 28. However, in contrast to Tl-201, the lower HLR cut-off of 2.5 suggests a relatively higher myocardial count density (greater than or equal to 9000 counts) rendering the image quality to be still satisfactory for subjective assessment.
Human ; Male ; Female ; Middle Aged ; Adult ; Young Adult ; Adolescent ; Child ; MYOCARDIAL PERFUSION IMAGING ; MYOCARDIAL SCINTIGRAPHY ; DIAGNOSIS ; DIAGNOSTIC TECHNIQUES AND PROCEDURES ; DIAGNOSTIC IMAGING ; CARDIAC IMAGING TECHNIQUES ; BODY MASS INDEX