Nitasha Singh

Royal Sussex County Hospital

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Mark Aplin

Copenhagen University Hospital

Sabina Dizdarevic

Brighton and Sussex Medical School

Maryam Jessop

University Hospitals Sussex NHS Foundation Trust

Patrick Begley

University Hospitals Sussex NHS Foundation Trust

Elena Missir

Brighton and Sussex Medical School

Puja K. Parekh

Weill Cornell Medicine

Helena McMeekin

Hermes Medical Solutions (United Kingdom)

Malgorzata Raczek

Sussex Partnership NHS Foundation Trust

Georgia Keramida

Guy's and St Thomas' NHS Foundation Trust

Sunil Nair

Countess of Chester Hospital

Cooperative Institutions

University Hospitals Sussex NHS Foundation Trust

Royal Sussex County Hospital

Brighton and Sussex Medical School

Genesys (United States)

University College London

King's College London

University of Pennsylvania

Royal Brompton & Harefield NHS Foundation Trust

King's College Hospital

Hammersmith Hospital

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Relationship between regional hepatic glucose metabolism and regional distribution of hepatic fat

Nuclear Medicine Communications (2019)

Alexander Dunford Georgia Keramida Nitasha Singh Mark Aplin A. Michael Peters

Hepatic steatosis is associated with insulin resistance and hyperinsulinaemia. Insulin stimulates hepatic glucokinase, even in insulin resistance, so hepatic glucose uptake is increased in hepatic steatosis. The study hypothesis was that hepatic glucose uptake is also influenced locally by fat, the hepatic distribution of which is heterogeneous.Sixty patients undergoing PET/CT using fluorine-18-fluorodeoxyglucose (F-FDG) had dynamic imaging of the liver for 30 min after injection before undergoing whole-body PET/CT at 60 min after injection. Hepatic F-FDG uptake was measured using Gjedde-Patlak-Rutland graphical analysis. Plot gradient (Ki), which represents hepatic blood clearance of F-FDG to phosphorylation, was normalized to intercept [V(0)], which represents the hepatic F-FDG distribution volume. The 60 min computed tomography (CT) was co-registered on to each of the 30 dynamic PET frames. This failed in 20 patients. A further seven patients with lymphoma and three with hepatic metastases were excluded. Within transaxial sections, the liver was divided into small regions of interest (ROIs) of 5×5 pixels each in sections of 5 mm (range: 118-586 ROIs/liver). CT density and Ki/V(0) were measured in each ROI.Throughout the 25-pixel ROIs in the individual liver, CT density and Ki/V(0) showed a significant negative correlation in 15/30 patients. It was significantly positive in only three (P=0.01). In some patients, parametric imaging showed regional concordance between Ki/V(0) and hepatic fat, identified as reduced CT density.In addition to systemic influences, hepatic glucose uptake is regionally linked to the distribution of hepatic fat. Increased metabolism could be the cause or result of local fat deposition.

Steatosis

Standardized uptake value

10.1097/mnm.0000000000000968

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Association between Body Mass Index (BMI) and [123I]-Ioflupane (DaTSCAN) availabilities in patients with parkinsonism using single-photon computed tomography-computed tomography (SPECT-CT)

Research Square (Research Square) (2023)

Puja K. Parekh Patrick Begley Maryam Jessop Mark Aplin Elena Missir

Abstract Aim [123I]-Ioflupane (DaTSCAN) has a high binding affinity to the dopamine (DA) transporter (DaT) and tenfold less affinity to serotonin (5-HT) transporter (SERT). Both neurotransmitters are considered to contribute to body weight regulation. This study assesses the association between Body Mass Index (BMI) and DaTSCAN availability in brain. Method Scans from 74 consecutive patients who had undergone DaTSCAN single-photon computed tomography-computed tomography (SPECT-CT were used to obtain semi and absolute quantitative data in several volumes of interest (VOIs). Relative semi-quantitative specific binding ratios (SBRs) from Chang attenuated SPECT were obtained from GE DaTQUANT. Absolute normalised concentration (NC) was calculated from attenuation/scatter corrected SPECT-CT images, using an adapted version of the EARL Ltd (European Association of Nuclear Medicine (EANM) Research 4 Life) template. Results SBRs did not correlate with BMI. However, NC values correlated negatively in the entire cohort, with the strongest correlation in the frontal (r= -0.649. p = 0.000), occipital (r= -0.555, p = 0.000) regions and pons (r= -0.555, p = 0.000). In the abnormal (n = 49) and SWEDD group (n = 11), NC of the frontal region was the most correlated with BMI (r= -0.570, p = 0.000; r=-0.813, p = 0.002, respectively). In the borderline group (n = 14), the left posterior putamen displayed the strongest correlation (r=-0.765, p = 0.001). Conclusion Absolute NC values demonstrate a strong inverse correlation with BMI, strongest in the extrastriatal regions. Due to the predominately non-overlapping distribution of DaT and SERT, this study suggests greater involvement of SERT in obesity with possible interplay with DA transmission.

Putamen

Emission computed tomography

10.21203/rs.3.rs-2780817/v1

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Comparison of MPI SPECT/CT scans acquired with LEHR collimator and reduced time IQ•SPECT system

Sara Ferreira Patrick Begley Maryam Jessop A. J. Aldous Nicolas Eftychiou

Poster: EANM 17 / E-TPW63 / Comparison of MPI SPECT/CT scans acquired with LEHR collimator and reduced time IQ•SPECT system by: Ferreira1, S. M. Ferreira1, P. Begley2, M. Jessop2, A. Aldous3, N. Eftychiou2, N. Singh2, S. Dizdarevic2, E. Sousa1; 1Lisbon School of Health Technology, Polytechnic Institute of Lisbon, Lisbon, PORTUGAL, 2Brighton and Sussex University Hospitals, Brighton, UNITED KINGDOM, 3North Cumbria University Hospitals, Cumbria, UNITED KINGDOM

Collimator

Spect imaging

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Early gated SPECT adenosine myocardial perfusion imaging may influence the therapeutic management of patients with coronary artery disease

Nuclear Medicine Communications (2015)

Sabina Dizdarevic Nitasha Singh Sunil Nair Adam de Belder Nicola Ryan

The aim of the study was to investigate whether myocardial perfusion imaging at 15 min after injection (T15) is more accurate in detecting coronary artery disease than that at 45 min (T45).Two-day stress/rest 99mTc-tetrofosmin gated SPECT was performed at T15 and T45 in 50 patients. Coronary angiography was considered when poststress and resting images were discordant. Tracer washout rates were calculated for the myocardium, liver, and subdiaphragmatic region. Perfusion sum difference scores were derived using QPS software.T15 and T45 were discordant in 18/50 (36%) patients. In 16/18 patients (89%) discordant deficits were more apparent at T15. A total of 13/16 patients underwent coronary angiography, of whom 12 had coronary artery disease. Poststress, but not resting, left ventricular ejection fraction was lower at T15 (P=0.02). Sum difference scores were higher at T15 [2.2 (1.9)] than at T45 [1.6 (1.7); P<0.05]. Tracer washout rates from the liver [46 (13.3)%] and subdiaphragmatic region [36 (21.3)%] were significant (P<0.0001), but there was no change in myocardial activity.T15 detected more abnormalities than did T45. The reduction in left ventricular ejection fraction after stress may result from adenosine-induced poststunning at T15. Accordingly, the T15 protocol may be useful in the assessment of hibernating myocardium. Contrasting myocardial and hepatic washout rates may be attributable to differential ABC transporter expression.

Washout

10.1097/mnm.0000000000000258

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Assessment of 2-hour Images for 99m Tc-HYNIC-TOC Studies Using Image Interpretation and Image Analysis

S. Sequeira Tavares Maryam Jessop Deborah Pencharz Eleonora Manca Nitasha Singh

Poster: EANM 19 / TEPS-67 / Assessment of 2-hour Images for 99mTc-HYNIC-TOC Studies Using Image Interpretation and Image Analysis by: C. R. Tavares1, M. Jessop1, D. Pencharz1, E. Manca1, N. Singh1, S. Figueiredo2; 1Royal Sussex County Hospital, Brighton, , 2Lisbon School of Health Technology, Lisbon, PORTUGAL

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Association between body mass index (BMI) and [123I]Ioflupane (DaTSCAN) availabilities in patients with parkinsonism using single-photon emission computed tomography–computed tomography (SPECT-CT)

European Journal of Hybrid Imaging (2023)

Puja K. Parekh Patrick Begley Maryam Jessop Mark Aplin Elena Missir

[123I]Ioflupane (DaTSCAN) has a high binding affinity to the dopamine (DA) transporter (DaT) and tenfold less affinity to serotonin (5-HT) transporter (SERT). Both neurotransmitters are considered to contribute to body weight regulation. This study assesses the association between body mass index (BMI) and DaTSCAN availability in brain.Scans from 74 consecutive patients who had undergone DaTSCAN single-photon emission computed tomography-computed tomography (SPECT-CT) were used to obtain semi- and absolute quantitative data in several volumes of interest (VOIs). Relative semi-quantitative specific binding ratios (SBRs) from Chang attenuated SPECT were obtained from GE DaTQUANT. Absolute normalised concentration (NC) was calculated from attenuation/scatter corrected SPECT-CT images, using an adapted version of the EARL Ltd (European Association of Nuclear Medicine (EANM) Research 4 Life) template. Scans were subdivided into either degenerative parkinsonism (abnormal = 49), borderline (n = 14) or scan without evidence of dopaminergic deficit (SWEDD = 11) using visual assessment and SBR values by two nuclear medicine consultants.SBRs did not correlate with BMI. However, NC values correlated negatively in the entire cohort, with the strongest correlation in the frontal (r = - 0.649. p = 0.000), occipital (r = - 0.555, p = 0.000) regions and pons (r = - 0.555, p = 0.000). In the abnormal (n = 49) and SWEDD group (n = 11), NC of the frontal region was the most correlated with BMI (r = - 0.570, p = 0.000; r = - 0.813, p = 0.002, respectively). In the borderline group (n = 14), the left posterior putamen displayed the strongest correlation (r = - 0.765, p = 0.001).Absolute NC values demonstrate a strong inverse correlation with BMI, strongest in the extrastriatal regions. Due to the predominately non-overlapping distribution of DaT and SERT, this study suggests greater involvement of SERT in obesity with possible interplay with DA transmission.

Emission computed tomography

Putamen

Spect imaging

10.1186/s41824-023-00181-6

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Comparison of Preoperative Imaging Modalities in Primary Hyperparathyroidism

Endocrine Abstracts (2022)

Muhammad Saad Usama Razi Charlie Sayer Nitasha Singh Charles Zammit

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Modalities

10.1530/endoabs.86.p315

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Validation of cell density and viability assays using Cedex automated cell counter

Biologicals (2010)

Li‐Chun Huang Wendy Lin Machiko Yagami Daphne ChingYu Tseng Emily Miyashita‐Lin

Viability assay

Linearity

Accuracy and precision

Cell counting

10.1016/j.biologicals.2010.01.009

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Citations (18)

Can early myocardial perfusion imaging influence therapeutic management

Journal of Nuclear Medicine (2011)

Emel Sarı Nitasha Singh Michael Peters Anil Vara Adam de Belder

1163 Objectives To investigate if gated SPECT myocardial perfusion imaging at 15 minutes is as accurate or more accurate in detecting coronary disease (CAD) than imaging at 45 minutes. Methods 49 patients referred for myocardial perfusion imaging consented to participate in the study. 2-day stress/rest Tc-99m-tetrofosmin gated SPECT was performed at 15 (T15) and 45 (T45) minutes after tracer injection. Images were visually assessed for quality and reported by 3 nuclear medicine physicians unaware of the time-point of image acquisition. Perfusion defects were visually analysed for site, extent and depth. The reporters were then un-blinded and a clinical consensus report issued. If T15 and T45 images were discordant, referring cardiologists were asked to consider angiography. Results Images were interpretable in 94% of T15 and 96% of T45 scans but discordant in 18 patients (37%). Of these 16/18 (89%) showed defects at T15 that were more apparent or not appreciable by visual analysis at T45. 8 patients with discrepant imaging had angiography. Of these 6 had CAD and 2 false positive results: 1 at T15 and the other at T15 and T45. Of the 6 patients with CAD, 1 had a reversible defect that was mild-moderate at T45 and mild at T15. This patient had an occluded small obtuse marginal artery that was managed medically. In the remaining 5 patients, perfusion defects were better visualised at T15 than at T45, with all defects being mild. 3 patients had angiographically mild-moderate disease managed medically but 2 patients required PCI. Conclusions A T15 stress/rest Tc-99m-tetrofosmin protocol gives clinically interpretable images of similar quality to T45. Our findings suggest T15 imaging allows a higher detection rate of small reversible perfusion defects that may be the result of minimal tracer redistribution at 45 minutes. Although these discordant defects were mild, correlation with angiography showed they were not artefactual but instead due to coronary disease, and hence may influence therapeutic management

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Reproducible lymph-to-blood transfer of Tc-99m-nanocolloid in a patient with abnormal lymphatic function

Vascular Medicine (2015)

Georgia Keramida Matthew Lee Mark Aplin Nitasha Singh A. Michael Peters

It is thought that lymphovenous communications may allow lymph to enter blood before the thoracic duct (TD). Whether this occurs physiologically1 or in response to lymphatic dysfunction2,3 is unclear. These images of a 54-year-old man who initially presented with right-sided, painless, intermittent, pitting lower limb swelling support the existence of such communications. He was initially investigated with lymphoscintigraphy. Five years later, the swelling became bilateral and he underwent further lymphoscintigraphy. On both occasions, 20 MBq of Tc-99m-nanocolloid (General Electric, UK) was injected subcutaneously into the first web spaces of both feet, followed by gamma camera imaging immediately after injection (0 min) and at 45 and 150 minutes post injection. He undertook no strenuous exercise before completion of imaging. Anterior projections (Panels B and D) illustrate very heavy hepatic and splenic activity at 150 minutes in the first and second studies. There was no activity in the liver at 0 or 45 minutes in either study (anterior projections; Panels A and C), excluding intravascular

Lymph duct

10.1177/1358863x15582289

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