Prevalence and significance of extracardiac uptake on pyrophosphate imaging in the SCAN-MP study: the first 379 cases.

INTRODUCTION: Technetium-labeled bone-avid radiotracers can be used to diagnose transthyretin cardiac amyloidosis (ATTR-CA). Extracardiac uptake of technetium pyrophosphate (Tc-99m PYP) in this context has not been extensively explored and its significance is not well characterized. We assessed extracardiac Tc-99m PYP uptake in individuals undergoing nuclear scintigraphy and the extent of clinically actionable findings. METHODS: The Screening for Cardiac Amyloidosis with Nuclear Imaging in Minority Populations (SCAN-MP) study utilizes Tc-99m PYP imaging to identify ATTR-CA in self-identified Black and Caribbean Hispanic participants ≥ 60 years old with heart failure. We characterized the distribution of extracardiac uptake, including stratification of findings by timing of scan (1 hour vs 3 hours after Tc-99m PYP administration) and noted any additional testing in these subjects. RESULTS: Of 379 participants, 195 (51%) were male, 306 (81%) Black race, and 120 (32%) Hispanic ethnicity; mean age was 73 years. Extracardiac Tc-99m PYP uptake was found in 42 subjects (11.1%): 21 with renal uptake only, 14 with bone uptake only, 4 with both renal and bone uptake, 2 with breast uptake, and 1 with thyroid uptake. Extracardiac uptake was more common in subjects with Tc-99m PYP scans at 1 hour (23.8%) than at 3 hours (6.2%). Overall, four individuals (1.1%) had clinically actionable findings. CONCLUSION: Extracardiac Tc-99m PYP uptake manifested in about 1 in 9 SCAN-MP subjects but was clinically actionable in only 1.1% of cases.

Advances in Imaging Techniques to Guide Therapies and Monitor Response to the Treatment of Musculoskeletal Injuries.

Continual advancements in diagnostic imaging have allowed for more accurate and complete diagnoses of injuries in the performance horse. The use of several different imaging tools has further allowed the equine sports medicine clinician to more carefully direct treatment options, monitor response to therapy and guide rehabilitation recommendations. The advancements in diagnostic imaging and novel treatment options have led to the improvement in the overall prognosis of many injuries that affect the horse and their performance. The purpose of this section is to review the advancements made in diagnostic imaging of the horse and to aid the practitioner in the selection of the appropriate modality and how best to use them to guide treatment and monitoring decisions.

Multimodality Imaging in Cardiac Amyloidosis.

PURPOSE OF REVIEW: Cardiac amyloidosis is an increasingly recognized condition with a growing range of targeted therapies, but diagnosis requires a high index of suspicion and multimodality imaging expertise. Early diagnosis remains key to improving quality of life and survival. This article reviews the multimodality imaging approach to the diagnosis, differentiation, and prognosis of cardiac amyloidosis. RECENT FINDINGS: Recent advances in multimodality cardiac imaging have allowed for earlier diagnosis of cardiac amyloidosis resulting in earlier initiation of life-saving therapy in cases of light chain amyloidosis and life-prolonging therapy in transthyretin amyloidosis. With these advances in multimodality imaging, it is important for cardiologists and cardiac imagers to be aware of the subtleties of early disease, the appropriate diagnostic approach as well as understanding the practicalities and pitfalls that are encountered with each modality.

Semi-quantitative methods yield greater inter- and intraobserver agreement than subjective methods for interpreting 99m technetium-hydroxymethylene-diphosphonate uptake in equine thoracic processi spinosi.

Scintigraphy is a standard diagnostic method for evaluating horses with back pain due to suspected thoracic processus spinosus pathology. Lesion detection is based on subjective or semi-quantitative assessments of increased uptake. This retrospective, analytical study is aimed to compare semi-quantitative and subjective methods in the evaluation of scintigraphic images of the processi spinosi in the equine thoracic spine. Scintigraphic images of 20 Warmblood horses, presented for assessment of orthopedic conditions between 2014 and 2016, were included in the study. Randomized, blinded image evaluation was performed by 11 veterinarians using subjective and semi-quantitative methods. Subjective grading was performed for the analysis of red-green-blue and grayscale scintigraphic images, which were presented in full-size or as masked images. For the semi-quantitative assessment, observers placed regions of interest over each processus spinosus. The uptake ratio of each processus spinosus in comparison to a reference region of interest was determined. Subsequently, a modified semi-quantitative calculation was developed whereby only the highest counts-per-pixel for a specified number of pixels was processed. Inter- and intraobserver agreement was calculated using intraclass correlation coefficients. Inter- and intraobserver intraclass correlation coefficients were 41.65% and 71.39%, respectively, for the subjective image assessment. Additionally, a correlation between intraobserver agreement, experience, and grayscale images was identified. The inter- and intraobserver agreement was significantly increased when using semi-quantitative analysis (97.35% and 98.36%, respectively) or the modified semi-quantitative calculation (98.61% and 98.82%, respectively). The proposed modified semi-quantitative technique showed a higher inter- and intraobserver agreement when compared to other methods, which makes it a useful tool for the analysis of scintigraphic images. The association of the findings from this study with clinical and radiological examinations requires further investigation.

Long-term functional renal outcomes after retroperitoneoscopic upper pole heminephrectomy for duplex kidney in children: a multicenter cohort study.

BACKGROUND: Retroperitoneoscopic upper pole heminephrectomy (RUHN) in duplex kidney in children remains a challenging procedure with a need for postoperative functional assessment of the remnant lower pole. We aimed to calculate the incidence of long-term functional renal outcomes in these children and examine the effect of age on those outcomes. METHODS: A multicenter retrospective cohort study of 9 years included all patients undergoing RUHN and evaluated by renal ultrasound (US) and dimercaptosuccinic acid (DMSA) scintigraphy pre and postoperatively. Patients were divided in two age groups of ≤12 and >12 months. Standard follow-up assessed pre-, intra- and postoperative outcomes using clinical review, US and DMSA. RESULTS: Standard RUHN in lateral position was performed in 30 patients. Five cases were excluded (2 lacks of postoperative DMSA, 3 conversions). Indications for RUHN were non-functioning upper moieties (n = 25) caused by ureterocele (n = 11), ectopic distal implantation of the ureter with incontinence (n = 6) or evolving severe ureterohydronephrosis (n = 8). Mean age at surgery was 30 ± 27 months, operation time 116 ± 52 min and hospital stay 2.8 ± 1 days. Long-term follow-up (mean, 7.2 ± 2.7 years) with US and DMSA showed that none of the 25 patients had complete loss of lower pole renal function. Mean lower pole renal function directly related to RUHN was not significantly different after versus before RUHN for the entire cohort (n = 24; 39.7 ± 7.90 % vs. 41.7 ± 6.74 %; p = 0350), for the ≤12-month (n = 6; 39.3 ± 4.18 vs. 41.3 ± 5.47; p = 0.493) and the >12-month groups (n = 18; 39.8 ± 8.90 vs. 41.9 ± 7.25; p = 0.443). Four patients (17 %) had partial loss of function (mean function loss, 9.3 ± 5.85 %; median age, 13 months). The number and type of complications between the two age groups were not statistically different. Overall, 29 % (n = 7/24) of the patients presented with medium-term (17 %) and long-term (17 %) complications directly related to RUHN. CONCLUSIONS: RUHN is a demanding yet efficient technique that is safe for the lower pole at any age. Systematic postoperative DMSA is not mandatory as long as US remains normal.

Splenosis with lower gastrointestinal bleeding mimicking colonical gastrointestinal stromal tumour.

BACKGROUND: Splenosis refers to the heterotopic transplantation of splenic tissue following splenic trauma or splenectomy. Splenosis is typically asymptomatic and is often identified incidentally. CASE PRESENTATION: We report a case of splenosis with colon and stomach invasion presenting as lower gastrointestinal bleeding and mimicking colonic gastrointestinal stromal tumour (GIST). The importance of suspicion for splenosis in patients with a history of splenic injury should be highlighted. Computed tomography (CT)-guided biopsy, nuclear scintigraphy and ferumoxide-enhanced magnetic resonance imaging (MRI) can support an accurate diagnosis. CONCLUSIONS: An accurate diagnosis of splenosis is important to avoid unnecessary operations, especially in patients with previous histories of splenic trauma or splenectomy.

Protean Presentations of Parathyroid Adenoma in Childhood.

Parathyroid adenoma is a rare disease which is known to present with protean manifestations, leading to misdiagnosis in the initial stage of the disease. It is known to pose a diagnostic dilemma to the clinician, in which a high index of suspicion alone often leads to a proper diagnosis and timely management. We encountered two such cases who presented to us with varied presentation, in which nuclear scintigraphy along with intraoperative parathyroid hormone assay played a major role in diagnosis and management.

Diagnostic sensitivity of bone scintigraphy for equine stifle disorders.

Disorders of the stifle are a common cause of lameness in horses yet the accuracy of scintigraphy for diagnosis of stifle conditions is controversial. The aim of retrospective cross-sectional study was to determine the diagnostic sensitivity (Se) of bone scintigraphy in detecting stifle disease and to determine if two orthogonal scintigraphic images improve diagnostic Se. Horses that underwent scintigraphic examination during a two-year period were included. Horses were divided into two groups: group 1 (N = 23) had lameness that was localized to the stifle by intra-articular analgesia and group 2 (N = 182) had lameness that was localized to a different location. Scintigraphic studies (one image or two images) were independently and retrospectively analyzed by two radiologists (R1 and R2). Sensitivity, specificity (Sp) and predictive values (PV), and were calculated for each type of study (one image or two images) and for each radiologist (R1 or R2). The Se to detect stifle disorders varied between radiologists (29.2% and 20.8%). The Sp was 84.5% and 88.3%. When two images were evaluated a decrease in the positive PV for both readers occurred. The Cohen kappa coefficient (κ) between readers was poor when one image (0.084) or two images (0.117) were evaluated. Findings from this study indicated that bone-phase nuclear scintigraphy is reasonably specific but highly insensitive for detecting lameness originating from the stifle in a diverse population of both normal and affected horses. The addition of a caudal scintigraphic image acquisition did not improve diagnostic sensitivity.

ABNORMAL IMAGING FINDINGS OF THE FEMORAL THIRD TROCHANTER IN 20 HORSES.

Injuries involving the femoral third trochanter are an uncommon but important source of equine lameness; however, clinical localization can be challenging. The purpose of this retrospective study was to describe ultrasonographic and scintigraphic findings in a group of horses with presumed third trochanter injury. Medical records of an equine referral hospital were searched from 2004-2014, and 20 horses met the inclusion criteria. Lesions consistent with third trochanter fracture were identified with ultrasound in 14/20 horses. Onset of lameness was acute (11), insidious (2), or unknown (1). All but one horse was lame at presentation, ranging from Grade 2-4/5. Ultrasound was the primary diagnostic modality in 5/14 horses with fragmentation, while scintigraphic findings of intense (3), moderate (5), and mild (1) increased radiopharmaceutical uptake (IRU) prompted ultrasonographic examinations in 9/14 fractured horses. A nondisplaced fracture was suspected in an additional horse with intense IRU and negative ultrasound findings. In the remaining five horses, imaging findings included only mild IRU. Lameness was localized to other regions in these cases. Six of 12 fractured horses with available outcome data were returned to function after a prolonged rehabilitation of 8-18 months. Scintigraphic findings helped to direct focused ultrasound exams in the majority of fracture cases. Horses with evidence of third trochanter fracture had similar clinical characteristics to that reported for pelvic fractures and authors therefore recommend ultrasonographic examination of both regions, especially when scintigraphy is unavailable. Prognosis for return to function in horses of the current study was less favorable than previously reported.

Parathyroid nuclear scan. A focused review on the technical and biological factors affecting its outcome.

OBJECTIVE: Technetium Parathyroid Scintigraphy (TS) is the most popular noninvasive localization procedure in patients with primary hyperparathyroidism (PHPT). Awareness of various factors involved in technetium uptake helps understand the outcome of TS. METHODS: We utilize a case of changing TS scans in a patient to review the literature on the various biological and technical factors involved in technetium uptake by the abnormal parathyroid tissue. A 56 year female was diagnosed with PHPT and osteopenia. An initial scan using (99m)Tc-Tetrofosmin showed no definite areas of abnormal parathyroid tissue. Patient refused surgical exploration, was started on Bisphosponates and subsequently monitored. Five years later she suffered fracture of her right wrist. A repeat TS using (99m)Tc-Sestamibi revealed hypervascular parathyroid lesion in the right lower neck. She underwent successful removal of a right lower parathyroid adenoma. RESULTS: Technical factors like the type of Tc isotope used, imaging techniques and biological factors like biochemical parameters (calcium, vitamin D levels), adenoma size, content of oxyphilic cells, vascularity can affect the outcome of the scan. CONCLUSION: Clinicians should be aware of technical and biological factors that could result in negative scan in parathyroid nuclear scintigraphy.

Epidemiology, diagnosis, and management of cardiac amyloidosis.

Cardiac amyloidosis (CA) is an infiltrative restrictive cardiomyopathy caused by the deposition of amyloid fibrils in the myocardium. It manifests in two primary subtypes: transthyretin cardiac amyloidosis (ATTR) and immunoglobulin light chain cardiac amyloidosis (AL). ATTR is further classified into wild-type and hereditary based on transthyretin gene mutation. Advances in diagnostics and therapeutics have transformed CA from a rare and untreatable condition to a more prevalent and manageable disease. Noninvasive diagnostic tools such as electrocardiography, echocardiography, and cardiac magnetic resonance can raise suspicion for CA; bone scintigraphy can non-invasively confirm ATTR, while AL necessitates histological confirmation. The severity of ATTR and AL can be assessed through serum biomarker-based staging. Treatment approaches differ, ranging from silencing or stabilizing transthyretin and degrading amyloid fibrils in ATTR to employing anti-plasma cell therapies and autologous stem cell transplantation in AL.

The Evaluation of Gastric Emptying Using Nuclear Scintigraphy Compared to Three-Dimensional Multi-detector Computed Tomography (3D-MDCT) Gastric Volumetry in the Assessment of Poor Weight Loss Following Sleeve Gastrectomy.

BACKGROUND: Poor weight loss and weight regain are principal challenges following laparoscopic sleeve gastrectomy (LSG). There is a lack of standardised assessments and diagnostic tests to stratify the status post-LSG and determine whether anatomical or physiological problem exists. We aimed to compare nuclear scintigraphy gastric emptying with CT volumetric analysis of sleeve anatomy and determine the impact of anatomy on physiological function and its correlation with weight loss. MATERIALS AND METHODS: Patients greater than 12 months post-LSG were categorised into optimal weight loss (OWL) (n = 29) and poor weight loss groups (PWL) (n = 50). All patients underwent a protocolised nuclear scintigraphy and three-dimensional multi-detector computed tomography (3D-MDCT) gastric volumetry imaging. RESULTS: Post-operative % total weight loss in OWL was 26.2 ± 10.5% vs. 14.2 ± 10.7% in the PWL group (p value < 0.0001). The PWL group had significantly more delayed gastric emptying half-time than OWL (34.1 ± 18.8 vs. 19.5 ± 4.7, p value < 0.0001). Gastric emptying half-time showed statistically significant correlations with weight loss parameters (BMI; r = 0.215, p value 0.048, %EWL; r = - 0.336, p value 0.002 and %TWL; r = - 0.379, p value < 0.001). The median gastric volume on 3D-MDCT did not differ between the OWL (246 (IQR 50) ml) and PWL group (262 (IQR 129.5) ml), p value 0.515. Nuclear scintigraphy gastric emptying half-time was the most highly discriminant measure. A threshold of 21.2 min distinguished OWL from PWL patients with 86.4% sensitivity and 68.4% specificity. CONCLUSION: Nuclear scintigraphy is a potentially highly accurate tool in the functional assessment of sleeve gastrectomy physiology. It appears to perform better as a diagnostic test than volumetric assessment. Gastric volume did not correlate with weight loss outcomes. We have established diagnostic criteria of greater than 21 min to assess sleeve failure, which is linked to suboptimal weight loss outcomes.

Kinetic Evaluation of the Hypoxia Radiotracers [18F]FMISO and [18F]FAZA in Dogs with Spontaneous Tumors Using Dynamic PET/CT Imaging.

Purpose: We evaluated the kinetics of the hypoxia PET radiotracers, [18F]fluoromisonidazole ([18F]FMISO) and [18F]fluoroazomycin-arabinoside ([18F]FAZA), for tumor hypoxia detection and to assess the correlation of hypoxic kinetic parameters with static imaging measures in canine spontaneous tumors. Methods: Sixteen dogs with spontaneous tumors underwent a 150-min dynamic PET scan using either [18F]FMISO or [18F]FAZA. The maximum tumor-to-muscle ratio (TMRmax) > 1.4 on the last image frame was used as the standard threshold to determine tumor hypoxia. The tumor time-activity curves were analyzed using irreversible and reversible two-tissue compartment models and graphical methods. TMRmax was compared with radiotracer trapping rate (k 3), influx rate (K i), and distribution volume (V T). Results: Tumor hypoxia was detected in 7/8 tumors in the [18F]FMISO group and 4/8 tumors in the [18F]FAZA group. All hypoxic tumors were detected at > 120 min with [18F]FMISO and at > 60 min with [18F]FAZA. [18F]FAZA showed better fit with the reversible model. TMRmax was strongly correlated with the irreversible parameters (k 3 and K i) for [18F]FMISO at > 90 min and with the reversible parameter (V T) for [18F]FAZA at > 120 min. Conclusions: Our results showed that [18F]FAZA provided a promising alternative radiotracer to [18F]FMISO with detecting the presence of tumor hypoxia at an earlier time (60 min), consistent with its favorable faster kinetics. The strong correlation between TMRmax over the 90-150 min and 120-150 min timeframes with [18F]FMISO and [18F]FAZA, respectively, with kinetic parameters associated with tumor hypoxia for each radiotracer, suggests that a static scan measurement (TMRmax) is a good alternative to quantify tumor hypoxia. Supplementary Information: The online version contains supplementary material available at 10.1007/s13139-022-00780-4.

Excimer laser coronary angioplasty versus manual aspiration thrombectomy in patients with ST-segment elevation myocardial infarction: analyzed by nuclear scintigraphy.

Clinical outcomes concerning the efficacy of excimer laser coronary angioplasty (ELCA) in real-world cases of acute myocardial infarction (MI) are limited. We evaluated and compared the impact of ELCA with manual aspiration thrombectomy on myocardial salvage and left ventricular (LV) systolic/diastolic function in patients with ST-segment elevation MI (STEMI) using nuclear scintigraphy.  We enrolled 143 consecutive patients with STEMI treated with ELCA (63 patients) or manual aspiration thrombectomy (80 patients) between September 2016 and December 2020 in a single-center hospital. We evaluated the peak creatine kinase (CK)/ creatine kinase-myocardial band (CK-MB) levels and performed single-photon emission computed tomography (SPECT) analyses with Quantitative Gated SPECT and Quantitative Perfusion SPECT (Auto QUANT 7.2) at 3-10 days using 123I-BMIPP and 3 months following percutaneous coronary intervention using 99mTc-tetrofosmin to evaluate myocardial salvage and LV systolic/diastolic function. No significant difference was observed in the patient and periprocedural characteristics. Peak CK-MB level was significantly different between the groups (ELCA group, 190.0 [70.5-342.0] IU/L vs. aspiration group, 256.5 [157.0-354.8] IU/L, p = 0.047). Although no significant difference was observed in myocardial salvage, significant improvement in the LV ejection fraction (14.1 [6.2-19.8]% vs. 9.5 [3.9-15.3]%, respectively, p = 0.018) and peak emptying rate (-0.54 [-1.02- (-0.27)] mL/s vs. -0.38 [-0.76- (-0.05)] mL/s, respectively, p = 0.017) were detected. ELCA could suppress the myocardial deviation enzymes and potentially improve systolic function compared to manual aspiration thrombectomy in patients with STEMI.

Changes in Oesophageal Transit, Macro-Reflux Events, and Gastric Emptying Correlate with Improvements in Gastro-Intestinal Symptoms and Food Tolerance Early Post Sleeve Gastrectomy.

PURPOSE: There are significant alterations in gastro-intestinal function, food tolerance, and symptoms following sleeve gastrectomy (SG). These substantially change over the first year, but it is unclear what the underlying physiological basis for these changes is. We examined changes in oesophageal transit and gastric emptying and how these correlate with changes in gastro-intestinal symptoms and food tolerance. MATERIAL AND METHODS: Post-SG patients undertook protocolised nuclear scintigraphy imaging along with a clinical questionnaire at 6 weeks, 6 months, and 12 months. RESULTS: Thirteen patients were studied: mean age (44.8 ± 8.5 years), 76.9% females, pre-operative BMI (46.9 ± 6.7 kg/m2). Post-operative %TWL was 11.9 ± 5.1% (6 weeks) and 32.2 ± 10.1% (12 months), p-value < 0.0001. There was a substantial increase of meal within the proximal stomach; 22.3% (IQR 12%) (6 weeks) vs. 34.2% (IQR 19.7%) (12 months), p = 0.038. Hyper-accelerated transit into the small bowel decreased from 6 weeks 49.6% (IQR 10.8%) to 42.7% (IQR 20.5%) 12 months, p = 0.022. Gastric emptying half-time increased from 6 weeks 19 (IQR 8.5) to 12 months 27 (IQR 11.5) min, p = 0.027. The incidence of deglutitive reflux of semi-solids decreased over time; 46.2% (6 weeks) vs. 18.2% (12 months), p-value < 0.0001. Reflux score of 10.6 ± 7.6 at 6 weeks vs. 3.5 ± 4.4 at 12 months, (p = 0.049) and regurgitation score of 9.9 ± 3.3 at 6 weeks vs. 6.5 ± 1.7, p = 0.021 significantly reduced. CONCLUSIONS: These data demonstrate that there is an increase in the capacity of the proximal gastric sleeve to accommodate substrate over the first year. Gastric emptying remains rapid but reduce over time, correlating with improved food tolerance and reduced reflux symptoms. This is likely the physiological basis for the changes in symptoms and food tolerance observed early post-SG.

Echocardiographic and clinical predictors of cardiac amyloidosis: limitations of apical sparing.

AIMS: The accuracy of an apical-sparing strain pattern on transthoracic echocardiography (TTE) for predicting cardiac amyloidosis (CA) has varied in prior studies depending on the underlying cohort. We sought to evaluate the performance of apical sparing and other TTE strain findings to screen for CA in an unselected population and determine the frequency that patients with echocardiographic concern for CA undergo evaluation for amyloidosis in clinical practice. METHODS AND RESULTS: As strain is routinely performed at our institution on all clinical TTEs, we identified all TTEs performed from 2016 through 2019 with reported concern for CA or apical sparing. We determined the performance characteristics for echocardiographic strain findings in discriminating CA including apical sparing, the ejection fraction to global longitudinal strain ratio (EF/GLS), and the septal apical-septal basal ratio (SA/SB); other clinical predictors of confirmed CA; and predictors of patients who underwent complete evaluation for CA. CA was confirmed by endomyocardial biopsy or diagnostic cardiac imaging. A total of 547 TTEs, representing 451 patients, reported concern for CA and had adequate strain for analysis. A total of 111 patients underwent complete evaluation for amyloidosis with 100 patients undergoing complete cardiac evaluation for CA. In those 100 patients, multivariable predictors of confirmed CA were age [odds ratio (OR) 3.37 per 5 years], a visual apical-sparing pattern (OR 10.85), and left ventricular ejection fraction (LVEF)/GLS > 4.1 (OR 35.37). CA was less likely in those with coronary artery disease (OR 0.04), hypertension (OR 0.18), and increased systolic blood pressure (OR 0.60 per 5 mm Hg increase). SA/SB [area under the curve (AUC) 0.72, 95% confidence interval (CI) 0.60-0.84] and LVEF/GLS (AUC 0.72, 95% CI 0.60-0.84) both had improved discrimination for CA compared with the apical-sparing ratio (AUC 0.66, 95% CI 0.54-0.79). Many patients with suggestive TTE findings did not receive an evaluation for amyloidosis. Complete evaluation was more likely with Caucasian race (OR 2.1), increased septal thickness (OR 1.4), increased body mass index (OR 1.2), and if the report specifically stated 'amyloid' (OR 1.9). Evaluations were less likely in patients with comorbidities. While hypertension reduced the likelihood of evaluating for CA, 34% of patients with CA had hypertension (>130/80 mm Hg) at time of diagnosis. CONCLUSIONS: In a broad population of patients undergoing TTE, apical sparing on strain imaging increased the likelihood of CA diagnosis but with modest sensitivity and specificity. GLS/EF ratio may be a more reliable tool to screen for CA. The low rate of complete evaluation in patients with concerning TTE findings indicates a strong need for practice improvement and enhanced disease awareness.

Delayed Gastric Emptying After Sleeve Gastrectomy Is Associated with Poor Weight Loss.

BACKGROUND: Intermediate to long-term weight regain is a major challenge following sleeve gastrectomy (SG). Physiological changes that mediate the extent of weight loss remain unclear. We aimed to determine if there were specific esophago-gastric transit and emptying alterations associated with weight regain. MATERIAL AND METHODS: Participants greater than 12 months post-SG were categorized into optimal (n = 29) and poor weight loss (PWL) (n = 72). All patients underwent a liquid contrast barium swallow demonstrating normal post-surgical anatomy and a protocolized nuclear scintigraphy designed specifically to characterize gastric emptying following SG. RESULTS: The %total weight loss in the optimal group was 26.2 ± 10.5 vs. 14.3 ± 8.8% in the PWL group (p = 0.001). Scintigraphy showed PWL had relatively increased gastric emptying half-time (GE 1/2t) 35 (IQR 23) min vs 19 (IQR 5.5) min (p = 0.001). The multivariate regressions delineated GE 1/2t as the best diagnostic measure for PWL (OR 1.16; CI 1.04-1.29, p-value 0.021). The probability of PWL increased by 16% for every 1-min increase above 21 min of GE 1/2t. A threshold of 21 min was found to have 88% sensitivity and 69% specificity predicting poor weight loss. CONCLUSION: Gastric emptying half-times greater than 21 min appear to reliably correlate with poor weight loss following SG. Additionally, further elevations above 21 min in emptying half-time increase the risk of poor weight loss. We have shown nuclear scintigraphy represents a simple and accurate diagnostic tool in patients who experience poor weight loss after SG, provided substantially altered reporting references in interpreting nuclear scintigraphy are applied.

Effects of parenteral administration of tylosin and ivermectin on abomasal emptying rate in healthy suckling lambs by use of nuclear scintigraphy.

Abomasal hypomotility is one of the important causes of neonatal mortality in small ruminants. Various pharmaceutical agents have been studied to address this problem in large ruminants. The aim of this study was to determine the effect of parenteral administration of tylosin and ivermectin on abomasal emptying rate in neonatal suckling lambs. Abomasal emptying rate was assessed using nuclear scintigraphic method in 10 healthy female Iranian fat tailed Ghezel lambs. Each lamb was tested three times, once as a control (1 ml of saline 0.9%, IM) and twice after the injection of tylosin (17.6 mg/kg, IM) and ivermectin (200 µg/kg, SC) in a crossover study. Based on radiopharmaceutical counts, remnant activity in abomasums at 90 min were 48.3 ± 3.5, 45.6 ± 7.5 and 41.6 ± 2.9% in control, tylosin and ivermectin groups, respectively. Administration of tylosin (p = 0.049) and ivermectin (p = 0.045) to lambs, significantly caused faster abomasal emptying rate compared to control. Evaluating the ROIs revealed that the half emptying time (T1/2) in control, tylosin and ivermectin groups were 67.1 ± 8.6, 62.6 ± 14.2 and 54.3 ± 9.9 min, respectively. These difference between all groups, statistically were significant (p = 0.026). However, the clinical efficacy of abomasal emptying rate facilitating by tylosin or ivermectin administration in lambs remains to be determined.

Expected Values of Esophageal Transit and Gastric Emptying Scintigraphy Post-uncomplicated Sleeve Gastrectomy.

PURPOSE: Sleeve gastrectomy (SG) results in significant anatomical and physiological alterations of the esophagus and stomach, including food tolerance. Currently, there is no consensus on the parameters of abnormal esophageal transit and gastric emptying in this population. We describe standardized esophageal transit and gastric emptying protocols, and define expected values following an uncomplicated SG. MATERIALS AND METHODS: In 43 asymptomatic post-SG patients with optimal weight loss, a standardized liquid and semi-solid (oatmeal) esophageal transit study, plus a 90-min semi-solid gastric emptying study with dynamic 5-s image acquisition to assess gastroesophageal reflux, was performed. Gastric emptying half-time and retention rate was calculated. Esophageal transit and reflux were graded by visual inspection of images. RESULTS: Thirty-one female and 12 male patients participated: mean age 49.0±10.7 years, pre-operative BMI 47.6±7.0 kg/m2, excess weight loss 58.8±26.0% at median follow-up of 7.4 months. The standardized semi-solid meal and liquid preparations were well tolerated. Delays in esophageal transit of liquid and semi-solid boluses were infrequent (7.0% and 16.3% respectively). Deglutitive reflux of both semi-solids and liquids was common (48.8% and 32.6%). The median semi-solid gastric emptying half-time was 21.0 min. A large proportion of substrate transited into the small bowel on initial image acquisition (median 39.1%). Reflux events during gastric emptying were common (median 5.0 events, 12.7% of image acquisition time). CONCLUSIONS: Rapid gastric emptying with asymptomatic deglutitive and post-prandial gastroesophageal reflux events are common following SG. We have defined the expected values of standardized esophageal transit and gastric emptying scintigraphy specifically tailored to SG patients.