photon emission
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2022 ◽  
Vol 11 ◽  
Franco Picciotto ◽  
Adriana Lesca ◽  
Luca Mastorino ◽  
Elena Califaretti ◽  
Luca Conti ◽  

Primary umbilical melanoma is rare tumor, representing about 5% of all umbilical malignancies.The lymphatic drainage from the tumor is challenging and can be to inguinal, axillary and retroperitoneal nodes. Dynamic and static lymphoscintigraphy with single-photon emission tomography/computed tomography (SPECT/CT) and sentinel lymph node biopsy (SLNB) is a widely validated technique in patients with clinically localized melanoma to search for and quantify nodal spread of cutaneous melanoma. Moreover, it offers the surgeon the preoperative information about the number and location of the sentinel lymph nodes (SLNs), which makes SLNB easier and quicker. This is the first report of an ulcerated thick melanoma of the umbilicus metastasizing only to an external iliac lymph-node without involvement of superficial inguinal SLNs. The preoperative high-resolution ultrasound (HR-US) examination of the regional lymph node field had been normal. This case-report shows how addition of SPECT/CT to planar imaging in a patient with clinically localized umbilical melanoma can help avoid incomplete SLNB when a deep SLN is not removed. A literature review of umbilical melanoma is also provided.

2022 ◽  
Vol 3 (3) ◽  

BACKGROUND Transient neurological deficits (TNDs) develop after cerebral revascularization in patients with moyamoya disease (MMD). The authors report a rare pediatric MMD case with extensive decreased cerebral blood flow (CBF) and prolonged TNDs after combined revascularization. OBSERVATIONS A 9-year-old boy presented with transient left upper limb weakness, and MMD was diagnosed. A right-sided combined surgery was performed. Two years after the surgery, frequent but transient facial (right-sided) and upper limb weakness appeared. The left internal carotid artery terminal stenosis had progressed. Therefore, a left combined revascularization was performed. The patient’s motor aphasia and right upper limb weakness persisted for approximately 10 days after surgery. Magnetic resonance angiography showed that the direct bypass was patent, but extensive decreases in left CBF were observed using single photon emission tomography. With adequate fluid therapy and blood pressure control, the neurological symptoms eventually disappeared, and CBF improved. LESSONS The environment of cerebral hemodynamics is heterogeneous after cerebral revascularization for MMD, and the exact mechanism of CBF decreases was not identified. TNDs are significantly associated with the onset of stroke during the early postoperative period. Therefore, appropriate treatment is desired after determining complex cerebral hemodynamics using CBF studies.

2022 ◽  
Vol 15 (1) ◽  
pp. 96
Elisabeth Plhak ◽  
Edith Gößnitzer ◽  
Reingard M. Aigner ◽  
Herbert Kvaternik

Dopaminergic transporter (DAT) imaging with single photon emission computed tomography (SPECT) is used to diagnose Parkinson’s disease and to differentiate it from other neurodegenerative disorders without presynaptic dopaminergic dysfunction. The radioiodinated tropane alkaloids [123I]FP-CIT and [123I]β-CIT enable the evaluation of the integrity of DATs. Commonly, the labeling of these compounds is performed by electrophilic substitution of the alkylstannylated precursors with radioactive iodine and following purification by HPLC or solid phase extraction (SPE). This work presents the first radioiodination of β-CIT and FP-CIT with no carrier added [131I]NaI on a Scintomics GRP synthesis module. Free iodine-131 and impurities were removed by SPE over a C-18 Sep-Pak cartridge. We achieved a radiochemical yield of >75% and a radiochemical purity of >98% with both compounds. Our development of an automated synthesis on a commercially available synthesizer ensures robust and efficient labeling of [131I]FP-CIT and [131I]β-CIT starting with low concentrated radioiodine.

2022 ◽  
Vol 8 ◽  
Xiaoyu Huang ◽  
Lingjuan Xu ◽  
Wei Wang ◽  
Weikun Hu ◽  
Xinyu Li ◽  

ObjectiveTo evaluate the correlations between Single-Photon Emission Computed Tomography (SPECT) parameters of salivary glands and dry eye parameters in patients with Sjögren's syndrome (SS).MethodsA total of 28 patients with SS participated in this prospective study. Dry eye assessments include tear film break-up time (TBUT), corneal fluorescein staining scoring (CFS), Schirmer's I test (SIT) examination and SPECT of salivary gland. The following quantitative parameters were derived from SPECT imaging for salivary glands: Uptake index (UI), the time needed to achieve the minimum counts after Vit C stimulation (Ts), and excretion fraction (EF). The relation between the aforementioned parameters and TBUT, CFS and SIT were analyzed with SPSS 22.0 software.ResultsAll the 28 eyes of the 28 subjects were examined. The mean SIT was 6.04 ± 4.64 mm/5 min (0–18 mm/5 min); the mean CFS was 3.07 ± 2.65 (0–10) and the mean BUT was 2.11 ± 1.97 s (0–9 s). The mean EF value was 0.52 ± 0.12 (0.26–0.75) in parotid glands and 0.45 ± 0.10 (0.30–0.67) in submandibular glands, respectively. The mean UI value was 9.33 ± 1.68 (6.03–13.20) in parotid glands and 9.92 ± 1.48 (7.08–12.60) in submandibular glands, respectively. The mean Ts (min) was 5.32 ± 3.01 (2.00–12.00) in parotid glands and 11.09 ± 7.40 (2.00- 29.00 min) in submandibular glands, respectively. It was found that EF positively correlates with SIT in patients with SS (r = 0.499 and 0.426 in parotid glands and submandibular glands, with P < 0.05), while no significant correlation was found between the UI, Ts and CFS, TBUT (P > 0.05).ConclusionsThe EF was positively correlated with SIT in patients with SS, it could reflex the dysfunction of salivary glands in SS patients. So, EF may be a valuable parameter for the diagnosis of SS patients with lacrimal gland secretion dysfunction.

2022 ◽  
Vol 12 ◽  
Steven R. D. Best ◽  
Natalie Haustrup ◽  
Dan G. Pavel

The difficulties of evaluating patients with complex neuropsychiatric conditions and prescribing appropriate treatments are well known. Imaging complements clinical assessments and allows a clinician to narrow the differential diagnosis by facilitating accurate and efficient evaluation. This is particularly relevant to neuropsychiatric conditions that are often diagnosed using a trial-and error process of exclusion. Single Photon Emission Computed Tomography (SPECT) is a functional brain imaging procedure that allows practitioners to measure the functional changes of gray matter structures based on regional cerebral blood flow (rCBF). The accurate diagnosis and treatment selection in psychiatry is challenging due to complex cases and frequent comorbidities. However, such complex neuropsychiatric conditions are increasingly benefitting from new treatment approaches, in addition to established medications. Among these are combination transcranial magnetic stimulation with ketamine infusions (CTK), hyperbaric oxygen therapy (HBOT) and perispinal administration of etanercept (PSE). This article provides readers with six case study examples that demonstrate how brain SPECT imaging can be used, both as a diagnostic tool, and as a potential biomarker for monitoring and evaluating novel treatments for patients with complex neuropsychiatric conditions. Six patients were assessed in our clinic and baseline brain SPECT imagesTourettes and a long history of alcohol were visually compared with SPECT images collected after periods of treatment with CTK or HBOT followed by PSE. This retrospective review demonstrates the clinical utility of these novel treatments and describes how SPECT imaging can complement standard diagnostic assessments. A novel display technique for SPECT images is described and we argue that SPECT imaging can be used for monitoring biomarker for clinical change.

2022 ◽  
Matej Kurtulik ◽  
Michal Shimanovich ◽  
Rafi Weill ◽  
Assaf Manor ◽  
Michael Shustov ◽  

Abstract Planck’s law of thermal radiation depends on the temperature, \(T\), and the emissivity, \(\epsilon\), which is the coupling of heat to radiation depending on both phonon-electron nonradiative-interactions and electron-photon radiative-interactions. In contrast, absorptivity, \(\alpha\), only depends on the electron-photon radiative-interactions. At thermodynamic equilibrium, nonradiative-interactions are balanced, resulting in Kirchhoff’s law of thermal radiation, \(\epsilon =\alpha\). For non-equilibrium, Quantum efficiency (QE) describes the statistics of photon emission, which like emissivity depends on both radiative and nonradiative interactions. Past generalized Planck’s equation extends Kirchhoff’s law out of equilibrium by scaling the emissivity with the pump-dependent chemical-potential \(\mu\), obscuring the relations between the body properties. Here we theoretically and experimentally demonstrate a prime equation relating these properties in the form of \(\epsilon =\alpha \left(1-QE\right)\). At equilibrium, these relations are reduced to Kirchhoff’s law. Our work lays out the evolution of non-thermal emission with temperature, which is critical for the development of lighting and energy devices.

2022 ◽  
Vol 2022 ◽  
pp. 1-6
Chang-Youn Moon ◽  
Kee-Suk Hong ◽  
Yong-Sung Kim

We investigate defect properties in hexagonal boron nitride (hBN) which is attracting much attention as a single photon emitter. Using first-principles calculations, we find that nitrogen-vacancy defect V N has a lower energy structure in C 1 h symmetry in 1− charge state than the previously known D 3 h symmetry structure. Noting that carbon has one more valence electron than boron species, our finding naturally points to the correspondence between V N and V N C B defects with one charge state difference between them, which is indeed confirmed by the similarity of atomic symmetries, density of states, and excitation energies. Since V N C B is considered as a promising candidate for the source of single photon emission, our study suggests V N as another important candidate worth attention, with its simpler form without the incorporation of foreign elements into the host material.

2022 ◽  
Vol 12 (1) ◽  
Chae Hong Lim ◽  
Hyun-Sook Kim ◽  
Kyung-Ann Lee ◽  
JongSun Kim ◽  
Soo Bin Park

AbstractWe investigated the diagnostic value of the maximum standardized uptake value (SUV) at hand and wrist joints for differentiating rheumatic diseases via bone single-photon emission computed tomography (SPECT)/computed tomography (CT). A total of 84 patients manifesting hand and wrist pain (58 women; age, 49.8 ± 15.4 years) were finally diagnosed with rheumatoid arthritis (RA, n = 42), osteoarthritis (OA, n = 16), fibromyalgia (FM, n = 2), and other rheumatic diseases (n = 24). The SUV of each patient was measured in 32 joints including the distal interphalangeal (DIP), proximal interphalangeal (PIP), metacarpophalangeal (MCP), and wrist joints bilaterally. Differences in pain and SUVs between specific rheumatic diseases were assessed using the chi-squared test or one-way analysis of variance. Using the highest SUV (hSUV) in each patient, the diagnostic performance in differentiating specific diseases was evaluated by receiver operating characteristic (ROC) curve analysis. Pain symptoms were present in 886 (33.0%) sites in a total of 2688 joints. In four joint groups (DIP, PIP, MCP, and wrist), the SUVs of joints with pain were significantly higher than those of pain-free joints (all P < 0.001). Active joint sites with higher SUVs than the median value of each joint group were the most common in RA (55.1%). RA showed the greatest hSUV in the PIP (3.0 ± 2.4), MCP (3.5 ± 3.4), and wrist (3.3 ± 1.9) joint groups. FM was characterized by the lowest hSUV of all joint groups. In ROC curve analysis, the cumulative hSUV of the PIP, MCP, and wrist joint groups showed good performance for evaluating RA (area under the curve (AUC), 0.668; P = 0.005). The summation of the hSUVs at all joint groups had an excellent predictive performance for FM (AUC, 0.878; P < 0.001). Consequently, the arthritic activity of the hand and wrist joints based on SUV differed according to specific rheumatic diseases. Quantitative SPECT/CT may provide objective information related to arthritic activity for differentiating specific rheumatic diseases.

Diagnostics ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 145
Sergey Gavrilov ◽  
Anatoly Karalkin ◽  
Nadezhda Mishakina ◽  
Oksana Efremova ◽  
Anastasia Grishenkova

The causes of chronic pelvic pain (CPP) in patients with pelvic venous disorder (PeVD) are not completely understood. Various authors consider dilation of pelvic veins (PeVs) and pelvic venous reflux (PVR) as the main mechanisms underlying symptomatic forms of PeVD. The aim of this study was to assess relationships of pelvic vein dilation and PVR with clinical manifestations of PeVD. This non-randomized comparative cohort study included 80 female patients with PeVD who were allocated into two groups with symptomatic (n = 42) and asymptomatic (n = 38) forms of the disease. All patients underwent duplex scanning and single-photon emission computed tomography (SPECT) of PeVs with in vivo labeled red blood cells (RBCs). The PeV diameters, the presence, duration and pattern of PVR in the pelvic veins, as well as the coefficient of pelvic venous congestion (CPVC) were assessed. Two groups did not differ significantly in pelvic vein diameters (gonadal veins (GVs): 7.7 ± 1.3 vs. 8.5 ± 0.5 mm; parametrial veins (PVs): 9.8 ± 0.9 vs. 9.5 ± 0.9 mm; and uterine veins (UVs): 5.6 ± 0.2 vs. 5.5 ± 0.6 mm). Despite this, CPVC was significantly higher in symptomatic versus asymptomatic patients (1.9 ± 0.4 vs. 0.7 ± 0.2, respectively; p = 0.008). Symptomatic patients had type II or III PVR, while asymptomatic patients had type I PVR. The reflux duration was found to be significantly greater in symptomatic versus asymptomatic patients (median and interquartile range: 4.0 [3.0; 5.0] vs. 1.0 [0; 2.0] s for GVs, p = 0.008; 4.0 [3.0; 5.0] vs. 1.1 [1.0; 2.0] s for PVs, p = 0.007; and 2.0 [2.0; 3.0] vs. 1.0 [1.0; 2.0] s for UVs, p = 0.04). Linear correlation analysis revealed a strong positive relationship (Pearson’s r = 0.78; p = 0.007) of CPP with the PVR duration but not with vein diameter. The grade of PeV dilation may not be a determining factor in CPP development in patients with PeVD. The presence and duration of reflux in the pelvic veins were found to be predictors of the development of symptomatic PeVD.

2022 ◽  
Vol 12 (1) ◽  
Michał Gawełczyk

AbstractWe calculate the spectrum of excited exciton states in application-relevant self-assembled pyramidal quantum dots grown in InAs/InP and InAs/AlGaInAs material systems. These types of dots have been recently shown to combine the emission in the third optical fiber window with low surface density and a reasonable level of in-plane symmetry of emitters, which predestines them for studies on single- and entangled-photon emission and for corresponding applications. The spectrum of optically active excited states is crucial for successful resonant and quasi-resonant excitation of emitters, allowing for conservation of angular momentum and addressing individual selected quantum states. Here, we show that in both types of studied dots, due to their specific morphology of truncated pyramid, the density of excited-state ladder, especially the s–p shell splitting may follow an unconventional dependence on emission energy, opposite to the one typically met in regular quantum dots. We obtain this result via modeling based on available morphological data and calculation within the multi-band $${{\varvec{k}} {\cdot } {\varvec{p}}}$$ k · p envelope-function theory combined with the configuration-interaction method used to calculate exciton states. Then, we explain this observation in purely geometric terms, as a result of an increasing effective quantum confinement width in a pyramid that is progressively cut from the top. Additionally, we show that the inverted trend is also manifested in the amount of electron-hole correlation in the exciton ground state, which also shows an anomalous dependence on emission energy and quantum dot volume.

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