SPECT Findings Research Articles

Parathyroid adenoma : radiologic features and correlation study with 99mTc-sestamibi spect findings

Parathyroid adenoma : radiologic features and correlation study with ^99mTc-sestamibi spect findings

Prognostic value of pulmonary diffusing capacity for carbon monoxide and ventilation-perfusion SPECT findings in pulmonary arterial hypertension.

Reduced pulmonary diffusing capacity for carbon monoxide (DLCO) can be observed in pulmonary arterial hypertension (PAH) and associates with increased mortality. However, the prognostic value of DLCO when corrected for haemoglobin (DLCOc), an independent modifier of DLCO, remains understudied. Additionally, the prognostic role of ventilation (V)-perfusion (Q) emission computed tomography (V/Q SPECT) findings in patients with PAH, which may concurrently be performed to rule out chronic thromboembolic pulmonary hypertension, is uncertain. A retrospective cohort study was conducted on 152 patients with PAH referred to a tertiary hospital for evaluation from January 2011 to January 2020. Lung function tests, clinical data and V/Q SPECT were ascertained. Cox regression analysis was performed to evaluate the association between DLCOc, DLCO and V/Q SPECT defects at referral with all-cause mortality. In equally adjusted Cox regression analysis, each percentage increase in DLCOc % predicted (%pred) (hazard ratio (HR) 0.97; 95% CI: 0.94-0.99) and DLCO%pred (HR 0.97; 95% CI: 0.94-0.99) was similarly associated with all-cause mortality. There was no detectable difference in area under the curve for prediction of all-cause mortality by DLCOc%pred and DLCO%pred (C-index 0.71 and 0.72, respectively, P=0.85 for difference). None of the defects noted on V/Q SPECT were significantly associated with mortality, but mismatched defects were associated with lower values of DLCOc%pred and DLCO%pred. DLCOc%pred and DLCO%pred perform equally as prognostic markers in PAH, supporting the use of either metric when available for prognostic stratification.

Characteristics of cerebrospinal fluid biomarkers/imaging findings in ptaients with amyloid PET‐negative dementia

AbstractBackgroundIn daily clinical practice, we often encounter cases with atypical clinical symptoms and imaging findings, even amoung those diagnosed with Alzheimer’s disease.MethodForty‐nine cases of undiagnosed patients with atypical clinical symptoms or imaging findings underwent both amyloid PET and cerebrospinal fluid(CSF) examinations.They were divided into amyloid‐positive group(n = 25) and amyloid‐negative group(n = 24).The cerebrospinal fluid findings,neuropsychological examination findings,MRI findings,and SPECT findings were compared between the two groups.ResultCSF findings showed significant differences in amyloid‐β42,amyloid‐β42/40, and P‐tau between the two groups.There was no significant difference in MRI findings.SPECT findings showed a significant difference in decreased blood flow in the right parietal lobe and bilateral precuneus.ConclusionIn dementia patients with atypical clinical symptoms and imaging findings, CSF findings and decreased blood flow in the right parietal lobe and bilateral precuneus are suggested to be useful indicators to distinguish whether amyloid is involved in the back ground pathology.

The Role of Myocardial Perfusion Imaging in the Prediction of Major Adverse Cardiovascular Events at 1 Year Follow-Up: A Single Center's Experience.

Myocardial perfusion imaging via single-photon emission computed tomography (SPECT MPI) is a well-established method of diagnosing coronary artery disease (CAD). The purpose of this study was to assess the role of SPECT MPI in predicting major cardiovascular events. The study population was composed of 614 consecutive patients (mean age: 67 years, 55% male) referred for SPECT MPI due to symptoms of stable CAD. The SPECT MPI was performed using a single-day protocol. We conducted a follow-up on all patients at 12 months via a telephone interview. The majority of our patients (78%) presented findings suggestive of reversible ischemia, fixed defects or both. Extensive perfusion defects were found in 18% of the population, while LV dilation was found in 7%. During the 12-month follow-up, 16 deaths, 8 non-fatal MIs and 20 non-fatal strokes were recorded. There was no significant association of SPECT findings with the combined endpoint of all-cause death, non-fatal MI and non-fatal stroke. The presence of extensive perfusion defects was an independent predictor of mortality at 12 months (HR: 2.90, 95% CI: 1.05, 8.06, p = 0.041). In a high-risk patient population with suspected stable CAD, only large reversible perfusion defects in SPECT MPI were independently associated with mortality at 1 year. Further trials are needed to validate our findings and refine the role of SPECT MPI findings in the diagnosis and prognosis of cardiovascular patients.

Baseline and Longitudinal Ioflupane SPECT Findings in DLB and MCI‐LB

AbstractBackgroundReduced striatal uptake on ioflupane SPECT is considered an indicative biomarker for Dementia with Lewy Bodies (DLB), and has been proposed as an indicative biomarker for Mild Cognitive Impairment with Lewy Bodies (MCI‐LB). Little data exists on the profile of uptake on key striatal regions of interest (ROIs) in DLB or MCI‐LB.MethodParticipants with DLB or MCI‐LB at baseline based on the presence of ≥2 core clinical DLB features, and ≥2 ioflupane SPECT scans performed approximately annually, were identified from the Mayo ADRC database. Minimum brain laterality z‐score values for the putamen (whole, anterior and posterior), caudate and striatum were determined using DaTQUANT 2 software. Baseline clinical and scan data was used for all analyses, and the annualized minimum putamen z‐change was determined on serial scans. The scan was considered abnormal if the minimum putamen z‐score was <‐0.98 based on clinicopathologic data.Result27 participants were included (21 DLB and 6 MCI‐LB, 96% male). Compared to MCI‐LB, DLB had a lower mean MoCA score and a trend toward a higher UPDRS score compared to MCI‐LB; there were no statistically significant differences in age, sex, onset age or duration of cognitive decline, or presence of other core DLB features. The majority (89%) had an abnormal scan at baseline. All ROI z‐scores showed the expected general trend of DLB<MCI‐LB, and the annualized z‐change was more negative in DLB, but none of the findings reached statistical significance.ConclusionThese findings suggest in MCI‐LB and DLB that 1) an abnormal ioflupane SPECT scan is frequently present at diagnosis, 2) z‐scores become more negative over time, and 3) the annualized z‐change is similar. Similar findings in larger cohorts would support the use of ioflupane SPECT as a biomarker in both MCI‐LB and DLB clinical trials.

SPECT findings on neuropsychiatric symptoms caused by nitrous oxide abuse.

The aim of the study was to investigate the clinical, neuropsychological, and regional cerebral blood flow (rCBF) perfusion changes in patients with neuropsychiatric symptoms caused by nitrous oxide (N2O) abuse. A total of 16 patients with neuropsychiatric symptoms caused by nitrous oxide abuse were recruited for this study. The study was carried out in the withdrawal phase of N2O abuse. A 925-1110 MBq 99mTc-ECD was administered intravenously. SPECT/CT images were collected with a low-energy and high-resolution collimator. The region uptake statistics of different brain regions of interest between patients with N2O abuse and normal people of the databases for younger subjects from the Scenium DB Comparison software were calculated automatically. The clinical manifestations of the 16 patients with neuropsychiatric symptoms were mood lability, anxiety, hallucination, delusion, agitation, confusion, and other psychiatric symptoms. In addition, 15 of the patients also complained of memory decline; 14 patients manifested numbness or paresthesia; 14 patients developed limb weakness, and their motor impairments were more severe in the lower limbs than in the upper limbs; and eight patients had urinary and defecation disturbances. In the neuropsychological examination, the BPRS score was 54.69 ± 11.48, the HAMD score was 30.00 ± 11.06, the HAMA score was 18.06 ± 5.77, the MMSE score was 28.06 ± 2.29, and the MoCA score was 25.06 ± 3.40. SPECT showed hypoperfusion in the frontal and temporal lobes, which is consistent with the clinical findings. This was the first study to demonstrate the obvious effect of N2O abuse on CBF in patients with neuropsychiatric symptoms. CBF perfusion imaging is helpful to detect the changes in the local brain functional activity in patients with N2O abuse.

Correction to: Unexpected (123I)FP-CIT SPECT findings: SWIDD, SWEDD and all DAT

Correction to: Unexpected (123I)FP-CIT SPECT findings: SWIDD, SWEDD and all DAT

247 Single-Photon Emission Computed Tomography (SPECT) In Predicting Localisation of Parathyroid Adenomas: A Closed-Loop Prospective Study

Abstract Aim to measure the sensitivity of SPECT in localising parathyroid adenomas particularly whilst attempting minimally invasive parathyroidectomy. Method 2-cycles prospective study correlating SPECT and operative findings was conducted. All patients underwent ultrasound and SPECT, those with concordant findings on both modalities underwent minimally invasive parathyroidectomy, whilst patients with discordant findings on both modalities had central neck exploration. Following operative findings, recommendations of changing the SPECT reporting method such as surgically relevant structures adjacent to the lesion, such as the thyroid, were implemented. Following which, a second prospective study assessed the outcome of change. Results In the first cycle, 20 patients underwent partial parathyroidectomy, either by open (n = 13), or minimally invasive (n = 7) approach. SPECT sensitivity was 85% (n = 17) in identifying the adenoma. Out of all histologically confirmed adenomas, SPECT identified all adenomas (n = 17) on the correct side and 41% (n = 7) on the correct level (superior vs. inferior parathyroid). In the second cycle following recommendation, 14 patients had surgery, 9 as minimally invasive and 5 as open approach. SPECT sensitivity was 79% (n = 11) for adenoma identification. Of all confirmed adenomas, SPECT identifying adenomas at the correct side increased to 91% (n = 10) and correct level to 91% (n = 10). Conclusions SPECT alone is not yet regarded as gold standard in parathyroid adenoma localisation. The study has demonstrated that feedback to the radiologist of the operative findings may enhance its usefulness, particularly in attempting to proceed with a minimally invasive parathyroidectomy.

Unexpected (123I)FP-CIT SPECT findings: SWIDD, SWEDD and all DAT.

Although the diagnosis of Parkinson's disease (PD) is essentially clinical, the implementation of imaging techniques can improve diagnostic accuracy. While some techniques (e.g. magnetic resonance imaging-MRI, computerized tomography-CT) are used to exclude secondary syndromes, presynaptic dopaminergic imaging including imaging of dopamine transporter (DAT)-can help the Neurologist in the differential diagnosis between neurodegenerative parkinsonian syndromes and parkinsonism without dopamine deficiency. DAT imaging can be useful in cases in which the clinical picture is not univocal, as in case of overlapping clinical features in patients with early disease, atypical syndromes or unsatisfying response to therapy. Currently, (123I)FP-CIT ([123I]N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane) (trade name DaTSCAN) is the only agent approved by international regulatory agencies for this purpose. With the increasing use of this technique, some unexpected findings have been reported, including patients clinically diagnosed with PD with a normal SPECT scan [e.g. Scans Without Evidence of Dopaminergic Deficit (SWEDD)]; PD patients with a greater dopaminergic deficit in the striatum ipsilateral to the clinicallymore affected side [e.g. Scans With Ipsilateral Dopaminergic Deficit (SWIDD)]; as well as some artifacts. Moreover, the neurologist must remember that structural lesions and administration of some drugs might alter the result of DAT imaging. Unexpected findings, artifacts, and misinterpretation of imaging findings can lead to an erroneous diagnosis and inappropriate therapy, neglect of other medical conditions that might explain the clinical picture, and undermine the selection phase in clinical trials. The aim of the present review is to bring clarity on these controversial (and sometimes erroneous) results, in order to informof these possibilities the clinicians requesting a DaTSCAN in clinical practice.

18F-Fluorocholine PET/CT Is More Sensitive Than 11C-Methionine PET/CT for the Localization of Hyperfunctioning Parathyroid Tissue in Primary Hyperparathyroidism.

Preoperative molecular imaging is paramount to direct surgery in primary hyperparathyroidism (pHPT). We investigated the diagnostic performance of 18F-fluorocholine (18F-FCH) PET/CT compared with 11C-methionine (11C-MET) PET/CT for localization of hyperfunctioning parathyroid tissue in patients with pHPT and negative or inconclusive 99mTc-sestaMIBI (99mTc-MIBI) SPECT findings. Methods: Fifty-eight patients with biochemical evidence of pHPT and negative or inconclusive 99mTc-MIBI SPECT findings were referred for presurgical detection and localization of hyperfunctioning parathyroid tissue by 11C-MET and 18F-FCH PET/CT. The PET/CT results were classified into 3 categories (positive, inconclusive, or negative) based on the nodular aspect of tracer uptake and the visualization of corresponding nodules on CT. The PET/CT results were correlated with the surgical and histopathologic findings, which were used as the gold standard. Results: Fifty-three patients were included for analysis. 18F-FCH PET/CT was positive in 39 patients (74%), inconclusive in 5 (9%), and negative in 9 (17%), compared with 25 (47%), 12 (23%), and 16 (30%), respectively, for 11C-MET PET/CT. 18F-FCH localized 11 additional foci (6 positive and 5 inconclusive), compared with 11C-MET. Twenty-six patients (sex ratio, 10/16 M/F) underwent surgery, with resection of 31 lesions (22 adenomas, 6 hyperplastic glands, and 3 carcinomas) and 1 normal gland. At follow-up, 21 patients (81%) were considered cured after surgery, whereas 3 patients (12%) had persistence of hypercalcemia. With inconclusive cases being considered negative, 18F-FCH PET/CT correctly localized 26 lesions in 24 of 26 patients (92%), compared with 16 lesions in 15 of 26 patients (58%) localized by 11C-MET PET/CT. Per-patient-based sensitivity and positive predictive value were 96% and 96%, respectively, for 18F-FCH and 60% and 94%, respectively, for 11C-MET (P < 0.0001). Per-lesion-based sensitivity and positive predictive value were 84% and 90%, respectively, for 18F-FCH and 52% and 94%, respectively, for 11C-MET (P < 0.0001). Conclusion: In the presence of biochemical evidence of pHPT with negative or inconclusive 99mTc-MIBI SPECT findings, 18F-FCH PET/CT performs better than 11C-MET PET/CT for the detection of pathologic parathyroid tissue, allowing localization of parathyroid adenoma or hyperplasia in 96% of patients.

Transthyretin cardiac amyloidosis scintigraphy, experience in a reference cardiology center

Funding AcknowledgementsType of funding sources: Public hospital(s). Main funding source(s): Instituto Nacional de Cardiologia Ignacio ChavezIntroductionTransthyretin cardiac amyloidosis (ATTR-CA) is a progressive disease that significantly reduces patients" quality of life and survival.1 In our country there are no statistics of this disease, only isolated cases. The ability to diagnose it has dramatically improved since the 2019 Multisociety Consensus for Multimodality Imaging.2,3 The study aimed to know patients" demographic and imaging characteristics in suspected ATTR-CA and the prevalence of positive cases in a reference Cardiology Center using 99mTc-pyrophosphate scintigraphy (99mTc-PYP).MethodsProspective, observational study approved by Institutional committees. We studied with 99mTc-PYP patients from November 2019 to December 2020 sent to the Nuclear Cardiology Department with clinical suspicion of ATTR-CA and negative light chain quantification. We included parameters as red flags, ECHO suggestive findings (septal thickness >12 mm, diastolic dysfunction), and MRI suggestive findings. ATTR-CA was diagnosed by clinical suspicious, positive scintigraphy, and negative serum studies. 99mTc-PYP were acquired according to current recommendations. Frequency distribution of categorical variables were reported as frequencies and percentages; continuous variables are presented in mean. Mann-Whitney U tests were conducted for continuous variables, while Fisher"s exact test was performed for categorical variables.ResultsDue to the Covid-19 pandemic, our Cardiology Hospital reconverted to covid attention; we studied a reduced number, and they were mainly inpatients: total 35 (28-inpatients, 7-outpatients). 21 (60%) were male, 14 (40%) were female, average age was 56.5 yo. 31%-heart failure diagnosis, 6%-history of carpal tunnel syndrome and 3%-spinal stenosis. ECHO: 26% had suggestive imaging, 43% with diastolic dysfunction, and 37% had a septal thickness >12mm. MRI: 42.9% had suggestive CA findings. No significant differences were found in the characteristics of suspicion between positive and negative patients. Regarding of the 35 patients scintigraphy, 7 (20%) were positives, establishing ATTR-CA diagnosis, 28 (80%) were negatives. The positivity probability was significant by H/Cl ratio, Perugini score, and SPECT findings (p 0.001). Until this protocol started and we share it among hospital physicians, we had never been asked to acquired this type of scintigraphy. Our study shows that if we purposely search for the disease, it can be found. The sample is small due to the limitations we had in the face of the pandemic; however, the study findings are significant for ATTR-CA diagnosis. It is striking that the ECHO and MRI suggestive findings were not statistically significant for the diagnosis. ConclusionsWe present the initial experience of the first study of cardiac amyloidosis in our country, to show the disease"s presence and that the diagnosis can be made effectively, quickly, economically, and non-invasively by nuclear medicine scintigraphy. Figure. 99mTc-PYP scan positive to ATTR-CA Figure. Patients characteristics

Feasibility of dual-phase 99mTc-MDP SPECT/CT imaging in rheumatoid arthritis evaluation.

To prospectively demonstrate the feasibility of performing dual-phase SPECT/CT for the assessment of the small joints of the hands of rheumatoid arthritis (RA) patients, and to evaluate the reliability of the quantitative and qualitative measures derived from the resulting images. A SPECT/CT imaging protocol was developed in this pilot study to scan both hands simultaneously in participants with RA, in two phases of 99mTc-MDP radiotracer uptake, namely the soft-tissue blood pool phase (within 15 minutes after radiotracer injection) and osseous phase (after 3 hours). Joints were evaluated qualitatively (normal vs. abnormal uptake) and quantitatively [by measuring a newly developed metric, maximum corrected count ratio (MCCR)]. Qualitative and quantitative evaluations were repeated to assess reliability. Four participants completed seven studies (all four were imaged at baseline, and three of them at follow-up after 1-month of arthritis therapy). A total of 280 joints (20 per hand) were evaluated. The MCCR from soft-tissue phase scans was significantly higher for clinically abnormal joints compared to clinically normal ones; P<0.001, however the MCCR from the osseous phase scans were not different between the two joint groups. Intraclass Correlation Coefficient (ICC) for MCCR was excellent [0.9789, 95% confidence interval (CI): 0.9734-0.9833]. Intra-observer agreement for qualitative SPECT findings was substantial for both the soft-tissue phase (kappa =0.78, 95% CI: 0.72-0.83) and osseous-phase (kappa =0.70, 95% CI: 0.64-0.76) scans. Extracting reliable quantitative and qualitative measures from dual-phase 99mTc-MDP SPECT/CT hand scans is feasible in RA patients. SPECT/CT may provide a unique means for assessing both synovitis and osseous involvement in RA joints using the same radiotracer injection.

Prognostic value of phase analysis on gated single photon emission computed tomography in patients with cardiac sarcoidosis

BackgroundWe aimed to determine the correlation between phase analysis, reflecting the heterogeneity of perfusion defects, and the dyssynchrony of the left ventricle wall motion, and adverse cardiac events in cardiac sarcoidosis (CS) patients. MethodsFifty-seven consecutive patients with diagnosed CS (64 [IQR 55–71] years old, 14 males), who underwent 18F-FDG PET/CT and ECG-gated SPECT, were studied. FDG PET was analysed to measure cardiac metabolic volume (CMV), and total lesion glycolysis (TLG). The SPECT findings, such as LVEF, Summed Rest Score (SRS), bandwidth (BW) were evaluated. ResultsThe median of BW was 56° (IQR 40–95). BW showed a strong inverse correlation with LVEF (r = − 0.60, P < 0.0001), and positive correlation with SRS (r = 0.82, P < 0.0001). However, there were no significant correlations between BW and CMV or TLG. The Kaplan–Meier curves revealed a significantly higher rate of MACE in the high BW group (BW > 56°) than the low BW group (BW ≤ 56°) (15.1%/years vs. 4.4%/years, P = 0.025). In multivariable analysis, BW was a significant independent predictor of MACE (P = 0.015). ConclusionPhase analysis on gated SPECT was a significant and independent predictor of MACE in patients with CS.

Clinical impact of 11C-Pittsburgh compound-B positron emission tomography in addition to magnetic resonance imaging and single-photon emission computed tomography on diagnosis of mild cognitive impairment to Alzheimer's disease.

This study aimed to evaluated the clinical impact of adding [11C] Pittsburgh compound-B (11C-PiB) PET for clinical diagnosis of mild cognitive impairment (MCI) to Alzheimer's disease (AD) dementia.Twenty six (mean age 78.5 ± 5.18 years, 21 females) AD (n = 7), amnestic MCI (n = 12), non-amnestic MCI (n = 3), vascular dementia, progressive supranuclear palsy (PSP) with frontotemporal dementia (FTD), FTD (n = 1 each), and normal (n = 1) patients underwent 11C-PiB-PET, MRI, and SPECT scanning. 11C-PiB-PET was compared with MRI and SPECT for clinical impact.11C-PiB-PET showed positivity in 6, 9, and 0 of the AD, amnestic MCI, and non-amnestic MCI patients, respectively, and 0 of those with another disease. Parahippocampal atrophy at VSASD was observed in 5 AD patients, 6 amnestic and PiB-positive MCI patients, 1 amnestic and PiB-negative MCI patient, and 1 vascular dementia patient. Parietal lobe hypoperfusion in SPECT findings was observed in 6, 4, and 2 of those, respectively, as well as 1 each of non-amnestic MCI, vascular dementia, and normal cases. Sensitivity/specificity/accuracy for selecting PiB-positive patients among the 15 MCI patients for 11C-PiB-PET were 100% (9/9)/100% (6/6)/100% (15/15), for VSRAD were 66.7% (6/9)/83.3% (5/6)/73.3% (11/15), and for SPECT were 44.4% (4/9)/50.0% (3/6)/46.7% (7/15), while those were 88.9% (8/9)/33.3% (2/6)/66.7% (10/15)/for combined VSRAD and SPECT. 11C-PiB-PET accuracy was significantly higher than that of SPECT.11PiB-PET alone may be useful for selecting patients who will progress from MCI to AD in the future, although follow-up study is necessary to clarify the outcome of MCI patients.

Technetium pyrophosphate nuclear scintigraphy for cardiac amyloidosis: Imaging at 1 vs 3 hours and planar vs SPECT/CT

BackgroundMulti-societal consensus recommendations endorse both planar and single photon emission tomographic (SPECT) image acquisitions for the evaluation of cardiac amyloidosis. However, the correlation between planar and SPECT findings and the optimal timing of image acquisitions remain uncertain. MethodsThis is an analysis of 109 consecutive patients who underwent technetium pyrophosphate nuclear scintigraphy for the evaluation of cardiac amyloidosis. Patients were imaged at 1 and 3 hours after radiotracer injection using both planar and SPECT/CT, and the correlations between imaging protocols were compared. ResultsIn the overall cohort (median age 77 years, 75% male), 33 patients had radiotracer localized to the myocardium on SPECT/CT images. There was strong correlation between 1- and 3-hour planar heart-to-contralateral lung ratios (mean difference 0.07, r = 0.94). However, there was discordance between planar image interpretation (based upon semiquantitative score and H/CL ratio) and myocardial localization of radiotracer on SPECT/CT in 17 patients (16%). The pattern of SPECT/CT uptake was identical at 1 and 3 hours in all cases (32 diffuse, 1 focal). ConclusionThese data support the recommendation that SPECT/CT should be obtained in addition to planar images when performing nuclear scintigraphy for the detection of cardiac amyloidosis. A 1-hour planar and SPECT/CT protocol appears optimal.

Ioflupane 123I (DAT scan) SPECT identifies dopamine receptor dysfunction early in the disease course in progressive apraxia of speech

To describe 123I-FP-CIT (DAT scan) SPECT findings in progressive apraxia of speech (PAOS) patients and to compare those findings with progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). PAOS is a neurodegenerative syndrome in which patients present with apraxia of speech, a motor speech disorder affecting programming and planning of speech. Patients with PAOS predictably develop Parkinsonism. DAT scan is a neuroimaging tool that assesses the integrity of presynaptic dopamine transporters in striatum and is usually abnormal in PSP and CBS. As part of an NIH-funded grant, we performed a DAT scan on 17 PAOS patients early in the disease course. DaTQUANT software was used to quantify uptake in the left and right caudate and anterior/posterior putamen, with striatum to background ratios (SBRs). The PAOS cohort was compared to 15 PSP and 8 CBS patients. Five PAOS patients (29%) showed abnormalities in at least one striatal region on DAT scan. When the five PAOS patients with abnormal DAT were compared to the PSP and CBS patients, the only difference observed was lower uptake in the posterior putamen in PSP (p = 0.03). There were no differences is putamen/caudate ratio or in symmetry of uptake, across all groups. There was also no difference in MDS-UPDRS-III scores between PAOS patients with and without abnormal DAT scans (p = 0.56). Abnormal DAT scan is observed early in the disease course in approximately 30% of PAOS patients, with striatal abnormalities similar to those in PSP and CBS.

Assessment of Sensitivity, Specificity, and Accuracy of Nuclear Medicines, CT Scan, and Ultrasound in Diagnosing Thyroid Disorders.

The study aims to investigate the specificity, sensitivity, and accuracy of nuclear medicine, CT scan, and ultrasonography to diagnose the disorders related to the thyroid gland. The study is based on the retrospective approach of recruiting 52 patients suffering from thyroid disorders. The demographic details of each patient have been recorded. Moreover, the results of previously conducted nuclear medicine scan, CT scan, and ultrasound have also been assessed. The findings of all the tests have been compared to evaluate and compare their sensitivity, specificity, and accuracy. A total of 52 patients were recruited for the study among which 41 were female and 11 were males. The findings of SPECT and MRI were compared, which revealed that MRI possessed 38.8% sensitivity and 22.22% specificity. As compared to the findings of CT scan, increased specificity (71.42%) and sensitivity (70.96%) have been identified in MRI. There is an increase in the sensitivity and specificity of MRI outcomes as compared to the nuclear medicine and CT scan.

Spect findings in Parkinson’s disease – 2nd report: Relevance to hallucinations induced by antiparkinsonian drugs

Spect findings in Parkinson’s disease – 2nd report: Relevance to hallucinations induced by antiparkinsonian drugs

ANALYSIS OF IOFLUPANE-SPECT FINDINGS USING DATQUANT IN PATIENTS WITH IDIOPATHIC REM SLEEP BEHAVIOR DISORDER

Reduced striatonigral uptake on ioflupane SPECT reflects dopamine deficiency, and this finding can be seen in patients with Lewy body disease (LBD) pathology. The patients with idiopathic REM sleep behavior disorder (iRBD) tend to have underlying LBD pathology, and a high percentage ultimately develop clinically-diagnosed dementia with Lewy bodies (DLB) or Parkinson's disease. We analyze ioflupane SPECT findings in patients with iRBD compared to Alzheimer's disease dementia (ADem; uptake tends to be normal) and DLB (uptake tends to be abnormal, using z-scores from DaTQUANT software (GE Healthcare). The mean DaTQUANT z-scores of the caudate and putamen for iRBD, ADem and DLB who had undergone ioflupane SPECT at the Mayo Alzheimer's Disease Research Center were analyzed and compared. Data on 22 iRBD patients (mean age 62.8 ± 7.6 years, 14 male) were analyzed and compared to 16 ADem and 40 DLB patients. The mean z-scores for each group of interest was iRBD - putamen: −0.19 ± 1.35 and caudate −0.09 ± 1.39; ADem - putamen: 0.47 ± 1.80 and caudate 0.89 ± 2.02, DLB - putamen: −1.99 ± 1.28 and caudate −2.40 ± 1.41. iRBD had z-scores which did not differ from ADem (putamen P=0.21, caudate p=0.08), but which were higher than DLB scores (putamen P<0.001, caudate P<0.001). Two (9%) iRBD patients had at least one z-score value <−1.5, compared to 1 (6%) for ADem (this patient had mixed LBD and Alzheimer's disease pathology) and 32 (80%) for DLB. The striatonigral uptake using DaTQUANT quantitation is reduced in a minority of iRBD patients. Analyses using longitudinal ioflupane SPECT and associated quantitation may provide insights on those iRBD patients who are evolving to DLB or Parkinson's disease. Supported by NIH grants (P50 AG016574, U01 AG006786, R01 AG015866, U01 NS100620), grant from GE Healthcare, Mayo Clinic Dorothy and Harry T. Mangurian Jr. Lewy Body Dementia Program, Deal Family Foundation and the Little Family Foundation.

Diastolic left ventricular functional indices: Comparison between gated myocardial perfusion SPECT and echocardiography

Introduction: Many patients have only diastolic dysfunction without any abnormality in systolic function. We compared cardiac diastolic parameters obtained by gated myocardial perfusion SPECT (Gated SPECT) with those evaluated by echocardiography. Methods: Forty-nine patients (aged 37-85 years, 19 males and 30 women) underwent Gated SPECT and echocardiography. Gated SPECT images were obtained with 16 frame/cardiac cycles. We derived the following diastolic indices: peak filling rate (PFR), time to PFR (TTPFR), mean filling rate in the first 1/3 of the diastole (MFR/3) and second filling rate (PFR2) due to left atrial contraction. In echocardiography we obtained the indices of ventricular filling: E wave, A wave, the E/A ratio, and the E wave deceleration time (DT) were considered. The LV isovolumic relaxation time (IVRT) was also determined. Results: There was no significant correlation between echocardiographic findings and diastolic gated SPECT findings. Using Post-Hoc One-way analysis significant difference was seen only in MFR/3 between diastolic dysfunction groups (P value=0.02). There was no significant difference in other diastolic gated SPECT variables in these groups. Conclusion: Diastolic parameters obtained from 16-frame/cardiac cycle gated SPECT didn’t correlate with echocardiographic indices.