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Akram Shmendi,1 Fraser Pirie,2 Datshana P Naidoo,3 Boikhutso Tlou,4 Wilfred Pilloy,5 Ayesha A Motala2 1Department of Medicine, 2Department of Diabetes and Endocrinology, 3Department of Cardiology, 4Department of Biostatistics, 5Department of Nuclear Medicine, University of KwaZulu-Natal, Durban, South Africa Background: The relationship between myocardial perfusion imaging (MPI) abnormalities, diabetes mellitus, and glucose control in South African populations is unknown. It was hypothesized that in subjects undergoing MPI for suspected coronary artery disease (CAD), those with diabetes would have more extensive perfusion defects and that diabetes control would influence MPI abnormalities. The aim of this study was to examine the relationship between the severity of CAD diagnosed with MPI in subjects with and without diabetes and to determine the relationship between diabetes control and extent of CAD.Methods: This study was a retrospective chart review of 340 subjects in whom MPI scans were performed over a 12-month period.Results: Subjects with diabetes had a higher prevalence of abnormal MPI, with more extensive ischemia, compared with subjects without diabetes (85.6% versus 68%; odds ratio 2.81, P

Meta-iodbenzylguanidine scintigraphy (MIBG scintigraphy) shows reduced uptake in idiopathic Parkinson's disease (IPD), idiopathic REM sleep behavior disorder (IRBD) and Lewy body dementia (LBD), but not in other parkinsonian or dementia syndromes. We retrospectively reevaluated 50 patients. Concordance rate between last clinical diagnosis and scintigraphy diagnosis was only given in two-thirds of the patients. Confounding factors were: decreasing heart/mediastinum ratio (HMR) with progressive age, higher HMR in women and possibly interference with antihypertensive medication. Standardization of the methods and precise clinical guidelines are warranted for better clinical use. [ABSTRACT FROM AUTHOR]

An investigation was performed to establish the usefulness of In-labelled polymer beads mixed into a standard meal as a tracer of gatrointestinal(GI)-motility changes due to the influence of various drugs. The labelled polymer beads were well mixed into the food, which was then fed to healthy beagle dogs undergoing drug therapy. GI motility was monitored using a gamma camera and data processor. The results were compared to those obtained from corresponding placebo studies on the same dogs. A significant acceleration of gastric emptying and colon transit was noted under the influence of a gastric and intestinal prokinetic coded R 51619. No influence on GI motility could, however, be detected after the administration of a calcium-blocking agent to the dogs. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) allows the creation of customized designs for various medical devices, such as implants, casts, and splints. Amongst other AM technologies, fused filament fabrication (FFF) facilitates the production of intricate geometries that are often unattainable through conventional methods like subtractive manufacturing. This study aimed to develop a methodology for substituting a pathological talus bone with a personalized one created using additive manufacturing. The process involved generating a numerical parametric solid model of the specific anatomical region using computed tomography (CT) scans of the corresponding healthy organ from the patient. The healthy talus served as a mirrored template to replace the defective one. Structural simulation of the model through finite element analysis (FEA) helped compare and select different materials to identify the most suitable one for the replacement bone. The implant was then produced using FFF technology. The developed procedure yielded commendable results. The models maintained high geometric accuracy, while significantly reducing the computational time. PEEK emerged as the optimal material for bone replacement among the considered options and several specimens of talus were successfully printed.

Background: Infection remains a major cause of morbidity and mortality, regardless of advances in antimicrobial therapy and improved knowledge of microorganisms. With the major global threat posed by antimicrobial resistance, fast and accurate diagnosis of infections, and the reliable identification of intractable infection, are becoming more crucial for effective treatment and the application of antibiotic stewardship. Molecular imaging with the use of nuclear medicine allows early detection and localisation of infection and inflammatory processes, as well as accurate monitoring of treatment response. There has been a continuous search for more specific radiopharmaceuticals to be utilised for infection imaging. This review summarises the most prominent discoveries in specifically bacterial infection imaging agents over the last five years, since 2019., Main Body: Some promising new radiopharmaceuticals evaluated in patient studies are reported here, including radiolabelled bacterial siderophores like [ 68 Ga]Ga-DFO-B, radiolabelled antimicrobial peptide/peptide fragments like [ 68 Ga]Ga-NOTA-UBI29-41, and agents that target bacterial synthesis pathways (folic acid and peptidoglycan) like [ 11 C]para-aminobenzoic acid and D-methyl-[ 11 C]-methionine, with clinical trials underway for [ 18 F]fluorodeoxy-sorbitol, as well as for 11 C- and 18 F-labelled trimethoprim., Conclusion: It is evident that a great deal of effort has gone into the development of new radiopharmaceuticals for infection imaging over the last few years, with remarkable progress in preclinical investigations. However, translation to clinical trials, and eventually clinical Nuclear Medicine practice, is apparently slow. It is the authors' opinion that a more structured and harmonised preclinical setting and well-designed clinical investigations are the key to reliably evaluate the true potential of the newly proposed infection imaging agents., (© 2024. The Author(s).)

Functional tumor imaging using Fluorodeoxyglucose positron emission tomography (FDG-PET) is a new method in clinical oncology. The 18 FDG, is a glucose analog that accumulates in cells in proportion to the rate of glucose metabolism, and increased carbohydrate metabolism has been recognized as a feature of malignant cells versus normal cells. In addition, it permits the detection of metastases or synchronous tumours not discovered by anatomic imaging. Although detection of the primary site of disease is usually accomplished well with conventional techniques, the performance of FDG-PET may be useful to determine tumours that are not clinically evident. The authors describe a case of early detection of synchronous thyroid carcinoma by FDG-PET in a young patient opereted on for a malignant melanoma on his arm.

Two thyroidal evaluation systems in euthyroid cats (n = 12) were compared. A single, confirmed hyperthyroid cat was included for interest. Firstly, thyroidal uptake of an intravenous bolus of approximately 111 MBq (3 mCi) 99MTcO4 was estimated by using a scintillation camera and calculating the ratio of thyroid to salivary activities at 20 min and 4 h. Thyroid to salivary activity ratios were 1:1 at 20 min and 2:1 at 4 h. Two discrete areas of salivary uptake were identified, namely a parotid/mandibular complex and a more rostral buccal/sublingual complex. These results were compared to radioiodine uptake of an oral dose of approximately 0.925 MBq (25 microCi) 131I using a standard thyroid uptake system, measured at 1, 2, 4, 6, 8, 10, 12, 24 and 48 h after administration. Mean radioiodine thyroidal uptake started at 33% at 1 h, stabilised at 21% between 4 and 24 h, and dropped to 18% at 48 h. There was a significant correlation between the early thyroid:salivary ratio of the parotid/mandibular complex and the radioiodine uptake at 12 h.

Wilson's disease rarely starts after the third decade and may present with misleading psychiatric signs. We observed a 39-year-old white male who developed hysterical behaviour followed by frank delusional psychosis. Secondary neurological symptoms like astasia and dyarthria were misinterpreted as drug-induced. Despite a treatment with D-penicillamine and zinc sulfate there was further deterioration with anarthria and pseudo-compulsive stereotypies. These latter signs cleared after five months, whereas astasia and abasia remained the same and MRI imaging showed further deterioration characterized by marked bilateral putaminal cavitation. SPECT imaging could not predict the clinical evolution. Our case emphasizes that Wilson's disease can have variable initial presentations, and confirms the relationship between pseudo-compulsive stereotypies and bilateral lenticular lesions, as already described in other diseases of the basal ganglia.

Single photon emission computed tomography of the brain can be useful in animal experimentation directed toward cerebral conditions. A well established and understood baboon model, necessarily under anesthesia, could be especially valuable in such investigations. Six normal baboons were studied under various anesthetic agents and their combinations: ketamine, thiopentone, pentobarbitone, and halothane. Cerebral blood flow (CBF) studies were performed with 99mTc-HMPAO. CBF effects from various anesthesia were detected, requiring careful choice of the anesthesia for cerebral investigations.

Human blood platelets labelled with indium-111 oxine have been shown to accumulate on damaged vascular surfaces and abnormal platelet deposition has been demonstrated in the carotid arteries of white stroke patients. Gamma scintigraphy of the carotid and cerebral arteries of 5 black stroke patients and 5 age- and sex-matched controls using 111In-labelled platelets showed no abnormal accumulation indicative of carotid artery disease.

A method has been developed to generate "condensed images" and to produce instantaneously time-activity curves from rectangular regions of interest. It uses readily available tomographic software. Examples of esophageal transit and thyroid perfusion are shown. Further developments are discussed.

In light of the high price of commercially available mercaptoacetyltriglycene (MAG3) it was decided to attempt a local MAG3-formation and to test this against diethylenetriamine pentaacetic acid (DTPA), 123I-Hippuran, and commercial MAG3 for diagnostic radiorenographic capabilities also in conjunction with furosemide and captopril. A baboon model (n = 6) was used, and the parameters evaluated were obtained by the "integral spleen" method of radiorenogram analysis. Although the images and parameters pointed to 123I-Hippuran and commercial MAG3 as the ideal renal scanning agents and to DTPA as the least so, with the local product an acceptable alternative, the differences were not significant enough to warrant either the purchase of the commercial product or the extensive development of the local product. Inexpensive 99mTc-DTPA in conjunction with modern computer techniques will probably supply most of the answers.

Endoscopy is at present the diagnostic technique of choice in the evaluation and detection of upper gastro-intestinal tract ulceration. Because of the physical discomfort suffered by patients during endoscopic examination, the search for better and less invasive methods of examination (especially in the unco-operative and seriously ill patient) continues. According to reports from the Orient, sucralfate (Ulsanic; Continental Ethicals) has prominent ulceravid properties. These properties are being used in conjunction with a tagging agent, in this case technetium-99m, as a diagnostic method for the detection and localization of upper gastro-intestinal ulceration. In this pilot study on 6 patients the positive findings of others regarding the specificity and promise of this method could not be confirmed.

In order to establish the efficacy of labelling a solid meal and a semi-solid meal with either 111In-labelled polymer beads or 99mTc-tin colloid beagle dogs were fed variously labelled meals of different consistencies and then monitored by scintigraphy for gastric motility patterns. The labelling with each tracer was either performed by thoroughly mixing it into the food before cooking, or alternatively by surface labelling after the food had been cooked. For the 99mTc-Sn-colloid tracer no difference was found in the measured gastric emptying times resulting from either pre-cooking labelling or surface labelling of the meals. Cooking the tracer together with the ingredients does however seem to promote a firm entrapment of the 111In-polymer beads into a solid protein, and in this manner the 111In-labelled resin appears to be a reliable solid food tracer. Surface labelling with 111In-polymer beads of a solid meal with a smooth texture fails totally and the tracer empties with the liquid phase.

A 99mTc-DTPA radiorenographic study, supported by excretory urography, blood chemistry and eventually histology was performed on 8 chacma baboons (Papio ursinus) after surgical induction of unilateral renal vein hypertension. Frequent sequential repeat renograms during 6 post-operative months detected fluctuating renal behaviour but did not reveal typical course of the disease. Neither did any one of the radiorenographic parameters (TP, T1/2, FF, relative clearances and perfusion) prove to be more sensitive than the others in detecting abnormalities. Initial microscopic or macroscopic haematuria and proteinuria in general eventually cleared up. Light microscopy demonstrated only mild abnormalities. The effects of venous occlusion of the kidney and the prognosis seemed to be variable as was reflected by radiorenography.

A set of controlled experimental animal procedures involving pharmacological and surgical interventions was carried out to assess the clinical validity of the parameters calculated by the "integral spleen" method of renography analysis. There appeared to be a good correlation between the observed changes of these parameters and current pathophysiological information. In particular, the described method includes an original calculation of the filtration fraction without blood and urine sampling or a second tracer injection. This calculation was experimentally validated here.

In order to assess the usefulness of inferior vena cava flow studies and cholescintigraphy complementary to the routine static liver scintigraphy in the differential diagnosis of hepatocellular carcinoma (HCC), we studied 37 patients with a proven diagnosis of HCC and 11 patients with a liver abcess or cyst. The procedure followed was 1) a 99mTc-colloid flow study of the inferior vena cava (IVC) and iliac veins followed by static liver imaging and 2) cholescintigraphy using a dynamic acquisition mode to determine the perfusion as well as the concentration/excretion of the liver and pathological area. The hepatic perfusion index (HPI) was calculated by the "slope" method of Sarper et al.: Radiology 141:179-184 (1981) and the "area" method of Biersack et al.: Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklear medizin. Erganzungsband 126:47-52 (1977). The results were compared with data previously collected in patients without liver disease (control) and other liver pathologies.

The cardiac status of 102 consecutive black stroke patients entered to the Medunsa Stroke Databank was determined. Cardiological examination, echocardiography and a gated blood pool scan revealed structural and/or functional cardiac abnormalities in 73.6% of patients. Rheumatic heart disease was diagnosed in 15.6%, mitral valve prolapse in 5.8% and mitral annulus calcification in 4.9% of cases. 'Possible' cardiac sources of cerebral embolism were detected in 22.5% and 'definite' sources in 23.5% of patients. Hypertensive heart disease was diagnosed in 35.2% and cardiomyopathy in 13.7% of the study population. Ischaemic heart disease was present in 6.86%. Ultrasonography revealed ventricular bands in 29.4% of patients. The high incidence of structural cardiac abnormalities detected by non-invasive means is in keeping with recent studies in white stroke patients.