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Background: The human reward system has been extensively studied using neuroimaging. This bibliometric analysis aimed to determine the global trend in diffusion magnetic resonance imaging (dMRI) and human reward research in terms of the number of documents, the most active countries and their collaborating countries, the top journals and institutions, the most prominent authors and most cited articles, and research hotspots. Methods: The research datasets were acquired from the Scopus database. The search terms used were 'reward' AND 'human' AND 'diffusion imaging' OR 'diffusion tensor imaging' OR 'diffusion MRI' OR 'diffusion-weighted imaging' OR 'tractography' in the abstract, article title and keywords. A total of 336 publications were analysed using Harzing's Publish or Perish and VOSviewer software. Results: The results revealed an upward trend in the number of publications with the highest number of articles in 2020 and 2022. Most publications were limited to countries, authors, and institutions in the USA, China and Europe. Bracht, Coenen, Wiest, Federspiel and Feng were among the top authors from Switzerland, Germany and the UK. Neuroimage, Neuroimage Clinical, Frontiers in Human Neuroscience, Human Brain Mapping, and the Journal of Neuroscience were the top journals. Among the top articles, six were reviews and four were original articles, while the top keywords in human reward research were 'diffusion MRI', 'adolescence', 'depression' and 'reward-related brain areas'. Conclusion: These findings may serve as researchers' references to find collaborative authors, relevant journals, cooperative countries/institutions, and hot topics related to dMRI and reward research.

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Primary breast tuberculosis is a rare disease under extrapulmonary tuberculosis category. It tends to affect females of reproductive age rather than postmenopausal women or prepubescent girls. This rare form of disease poses a challenge in diagnosing as imaging can mimic the appearance of both benign and malignant breast lesions. We describe a case of primary breast tuberculosis in a young female who presented with a persistent left breast lump. and was diagnosed with chronic left breast abscess. Histopathological examination of the lesion was consistent with granulomatous mastitis, secondary to mycobacterium tuberculosis infection. The patient was treated with a 6-month course of anti-tuberculosis drug with complete resolution of the symptoms and the left breast lesion on serial ultrasound imaging.

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Cerebral small vessel disease (CSVD) is a leading cause of age-related microvascular cognitive decline, resulting in significant morbidity and decreased quality of life. Despite a progress on its key pathophysiological bases and general acceptance of key terms from neuroimaging findings as observed on the magnetic resonance imaging (MRI), key questions on CSVD remain elusive. Enhanced relationships and reliable lesion studies, such as white matter tractography using diffusion-based MRI (dMRI) are necessary in order to improve the assessment of white matter architecture and connectivity in CSVD. Diffusion tensor imaging (DTI) and tractography is an application of dMRI that provides data that can be used to non-invasively appraise the brain white matter connections via fiber tracking and enable visualization of individual patient-specific white matter fiber tracts to reflect the extent of CSVD-associated white matter damage. However, due to a lack of standardization on various sets of software or image pipeline processing utilized in this technique that driven mostly from research setting, interpreting the findings remain contentious, especially to inform an improved diagnosis and/or prognosis of CSVD for routine clinical use. In this minireview, we highlight the advances in DTI pipeline processing and the prospect of this DTI metrics as potential imaging biomarker for CSVD, even for subclinical CSVD in at-risk individuals.

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Light-emitting diodes (LEDs) could be a potential dosimetry candidate because they are radiation hard, spectrally selective, direct band gap, and low-cost devices. Thus, an LED-based detector prototype was designed and characterized for dosimetry. A 20 × 20 cm2array of surface mount device LED chips was sandwiched in photovoltaic mode between two intensifying screens to form a dosimetric system. The system was enclosed in a light-tight air cavity using black vinyl tape. The screens converted diagnostic x-ray beams into fluorescent blue light. LEDs, applied in detector mode, converted the fluorescent light into radiation-induced currents. A digital multimeter converted the analog currents into digital voltage signals. Prototype characterization was executed using (a) IEC 61267's RQR 7 (90 kVp) and RQR 8 (100 kVp) beam qualities, and (b) low (25 mAs) and high (80 mAs) beam quantities. A standard dosimeter probe was simultaneously exposed with the prototype to measure the prototype's absorbed dose. In all exposures, the x-ray beams were perpendicularly incident on both the dosimeter and prototype, at a fixed source to detector distance-60 cm. The LED array prototype's minimum detectable dose was 0.139 mGy, and the maximum dose implemented herein was ∼13 mGy. The prototype was 99.18% and 98.64% linearly sensitive to absorbed dose and tube current-time product (mAs), respectively. The system was ±4.69% energy, ±6.8% dose, and ±7.7% dose rate dependent. Two prototype data sets were 89.93% repeatable. We fabricated an ultrathin (5 mm), lightweight (130 g), and a relatively low-cost LED-based dosimetric prototype. The prototype executed a simple, efficient, and accurate real-time dosimetric mechanism. It could thus be an alternative to the current passive dosimetric systems.

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This study compares the real-time dosimetric performance of a bpw34 photodiode (PD) and cold white light-emitting diodes (LEDs) based on diagnostic X-ray-induced signals. Signals were extracted when both the transducers were under identical exposure settings, including source-to-detector distance (SDD), tube voltage (kVp), and current-time product (mAs). The transducers were in a photovoltaic configuration, and black vinyl tape was applied on transducer active areas as a form of optical shielding. X-ray beam spectra and energies were simulated using Matlab-based Spektr functions. Transducer performance analysis was based on signal linearity to mAs and air kerma, and sensitivity dependence on absorbed dose, energy, and dose rate. Bpw34 PD and cold white LED output signals were 84.8% and 85.5% precise, respectively. PD signals were 94.7% linear to mAs, whereas LED signals were 91.9%. PD and LED signal linearity to dose coefficients were 0.9397 and 0.9128, respectively. Both transducers exhibited similar dose and energy dependence. However, cold white LEDs were 0.73% less dose rate dependent than the bpw34 PD. Cold white LEDs demonstrated potential in detecting diagnostic X-rays because their performance was similar to that of the bpw34 PD. Moreover, the cold white LED array's dosimetric response was independent of the heel effect. Although cold white LED signals were lower than bpw34 PD signals, they were quantifiable and electronically amplifiable.

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Numerous instruments such as ionization chambers, hand-held and pocket dosimeters of various types, film badges, thermoluminescent dosimeters (TLDs) and optically stimulated luminescence dosimeters (OSLDs) are used to measure and monitor radiation in medical applications. Of recent, photonic devices have also been adopted. This article evaluates recent research and advancements in the applications of photonic devices in medical radiation detection primarily focusing on four types; photodiodes - including light-emitting diodes (LEDs), phototransistors-including metal oxide semiconductor field effect transistors (MOSFETs), photovoltaic sensors/solar cells, and charge coupled devices/charge metal oxide semiconductors (CCD/CMOS) cameras. A comprehensive analysis of the operating principles and recent technologies of these devices is performed. Further, critical evaluation and comparison of their benefits and limitations as dosimeters is done based on the available studies. Common factors barring photonic devices from being used as radiation detectors are also discussed; with suggestions on possible solutions to overcome these barriers. Finally, the potentials of these devices and the challenges of realizing their applications as quintessential dosimeters are highlighted for future research and improvements.

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