Myocardial blood flow quantification with SPECT.

INTRODUCTION: The addition of absolute myocardial blood flow (MBF) data improves the diagnostic and prognostic accuracy of relative perfusion imaging with nuclear medicine. Cardiac-specific gamma cameras allow measurement of MBF with SPECT. METHODS: This paper reviews the evidence supporting the use of SPECT to measure myocardial blood flow (MBF). Studies have evaluated SPECT MBF in large animal models and compared it in humans with invasive angiographic measurements and against the clinical standard of PET MBF. The repeatability of SPECT MBF has been determined in both single-site and multi-center trials. RESULTS: SPECT MBF has excellent correlation with microspheres in an animal model, with the number of stenoses and fractional flow reserve, and with PET-derived MBF. The inter-user coefficient of variability is ∼20% while the COV of test-retest MBF is ∼30%. SPECT MBF improves the sensitivity and specificity of the detection of multi-vessel disease over relative perfusion imaging and provides incremental value in predicting adverse cardiac events. CONCLUSION: SPECT MBF is a promising technique for providing clinically valuable information in the assessment of coronary artery disease.

Comparison of Lidocaine and Mepivacaine for Variation in Regional Tissue Oxygenation in Stellate Ganglion Block: A Randomized, Double-Blind, Crossover Trial.

Introduction This prospective, randomized, double-blind, crossover trial aimed to investigate the effect of different types of local anesthetics on regional tissue blood oxygenation on the stellate ganglion block (SGB). Methods Twenty eligible patients were recruited for this study; 16 of whom were allocated to the study protocol. Participants were randomized into one of the two crossover sequences: 1% lidocaine hydrochloride or 1% mepivacaine hydrochloride, and received SGBs with 6 mL of any one of the local anesthetics, followed by a washout period of more than 24 hours, and then received SGBs by substituting the two local anesthetics. The tissue oxygenation index (TOI) in the skin near the mental foramen on the blocked side was recorded using near-infrared spectroscopy at 15 minutes after the local anesthetic injection. Results One participant did not complete the study. As such, variation in regional tissue oxygenation was compared between the 15 participants. There was no difference in the increase in regional tissue blood flow or tissue oxygenation after SGB between the patients who were given lidocaine and the ones who were given mepivacaine; however, the kinetics of the increase in regional tissue oxygenation were significantly faster with mepivacaine than with lidocaine. Conclusions Different types of local anesthetics do not affect the intensity of the increase in regional tissue oxygenation after SGB, but they do affect the kinetics of the increase. These differences in local anesthetics may affect how patients feel after receiving SGB, the duration of SGB effects, and the frequency of adverse events associated with SGB.

Multicenter Evaluation of the Feasibility of Clinical Implementation of SPECT Myocardial Blood Flow Measurement: Intersite Variability and Imaging Time.

BACKGROUND: Single-center studies have shown that single photon emission computed tomography myocardial blood flow (MBF) measurement is accurate compared with MBF measured with microspheres in a porcine model, positron emission tomography, and angiography. Clinical implementation requires consistency across multiple sites. The study goal is to determine the intersite processing repeatability of single photon emission computed tomography MBF and the additional camera time required. METHODS: Five sites (Canada, Italy, Japan, Germany, and Singapore) each acquired 25 to 35 MBF studies at rest and with pharmacological stress using technetium-99m-tetrofosmin on a pinhole-collimated cadmium-zinc-telluride-based cardiac single photon emission computed tomography camera with standardized list-mode imaging and processing protocols. Patients had intermediate to high pretest probability of coronary artery disease. MBF was measured locally and at a core laboratory using commercially available software. The time a room was occupied for an MBF study was compared with that for a standard rest/stress myocardial perfusion study. RESULTS: With motion correction, the overall correlation in MBF between core laboratory and local site was 0.93 (range, 0.87-0.97) at rest, 0.90 (range, 0.84-0.96) at stress, and 0.84 (range, 0.70-0.92) for myocardial flow reserve. The local-to-core difference in global MBF (bias-MBF) was 5.4% (-3.8% to 14.8%; median [interquartile range]) at rest and 5.4% (-6.2% to 19.4%) at stress. Between the 5 sites, bias-MBF ranged from -1.6% to 11.0% at rest and from -1.9% to 16.3% at stress; the interquartile range in bias-MBF was between 9.3% (4.8%-14.0%) and 22.3% (-10.3% to 12.0%) at rest and between 17.0% (-11.3% to 5.6%) and 33.3% (-10.4% to 22.9%) at stress and was not significantly different between most sites. Both bias and interquartile range were like previously reported interobserver variability and less than the SD of the test-retest difference of 30%. The overall difference in myocardial flow reserve was 1.52% (-10.6% to 11.3%). There were no significant differences between with and without motion correction. The average additional acquisition time varied between sites from 44 to 79 minutes. CONCLUSIONS: The average bias-MBF and bias-MFR values were small with standard deviations substantially less than the test-retest variability. This demonstrates that MBF can be measured consistently across multiple sites and further supports that this technique can be reliably implemented. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03427749.

Acute Blood Flow Responses to Varying Blood Flow Restriction Pressures in the Lower Limb.

The purpose of this study was to investigate lower limb blood flow responses under varying blood flow restriction (BFR) pressures based on individualized limb occlusion pressures (LOP) using a commonly used occlusion device. Twenty-nine participants (65.5% female, 23.8 ± 4.7 years) volunteered for this study. An 11.5cm tourniquet was placed around participants' right proximal thigh, followed by an automated LOP measurement (207.1 ± 29.4mmHg). Doppler ultrasound was used to assess posterior tibial artery blood flow at rest, followed by 10% increments of LOP (10-90% LOP) in a randomized order. All data were collected during a single 90-minute laboratory visit. Friedman's and one-way repeated-measures ANOVAs were used to examine potential differences in vessel diameter, volumetric blood flow (VolFlow), and reduction in VolFlow relative to rest (%Rel) between relative pressures. No differences in vessel diameter were observed between rest and all relative pressures (all p < .05). Significant reductions from rest in VolFlow and %Rel were first observed at 50% LOP and 40% LOP, respectively. VolFlow at 80% LOP, a commonly used occlusion pressure in the legs, was not significantly different from 60% (p = .88), 70% (p = .20), or 90% (p = 1.00) LOP. Findings indicate a minimal threshold pressure of 50%LOP may be required to elicit a significant decrease in arterial blood flow at rest when utilizing the 11.5cm Delfi PTSII tourniquet system.

Value of Micro Flow Imaging in the Prediction of Adenomatous Polyps.

OBJECTIVE: The aim of this study was to assess the value of micro flow imaging (MFI) in distinguishing adenomatous polyps from cholesterol polyps. METHODS: A total of 143 patients who underwent cholecystectomy for gallbladder polyps were retrospectively analyzed. B-mode ultrasound (BUS), color Doppler flow imaging (CDFI), MFI and contrast-enhanced ultrasound (CEUS) were performed before cholecystectomy. The weighted kappa consistency test was used to evaluate the agreement of vascular morphology among CDFI, MFI and CEUS. Ultrasound image characteristics, including BUS, CDFI and MFI images, were compared between adenomatous polyps and cholesterol polyps. The independent risk factors for adenomatous polyps were selected. The diagnostic performance of MFI combined with BUS in determining adenomatous polyps was compared with CDFI combined with BUS. RESULTS: Of the 143 patients, 113 cases were cholesterol polyps, and 30 cases were adenomatous polyps. The vascular morphology of gallbladder polyps was more clearly depicted by MFI than CDFI, and it had better agreement with CEUS. Differences in maximum size, height/width ratio, hyperechoic spot and vascular intensity on CDFI and MFI images were significant between adenomatous polyps and cholesterol polyps (p < 0.05). The maximum size, height/width ratio, and vascular intensity on MFI images were independent risk factors for adenomatous polyps. For MFI combined with BUS, sensitivity, specificity and accuracy were 90.00%, 94.69% and 93.70%, respectively. Area under the receiver operating characteristic curve (AUC) of MFI combined with BUS was significantly higher than that of CDFI combined with BUS (AUC = 0.923 vs. 0.784). CONCLUSION: Compared with CDFI combined with BUS, MFI combined with BUS had higher diagnostic performance in determining adenomatous polyps.

An eighth note.

Venous stenosis is the most common cause of arteriovenous fistula (AVF) failure in hemodialysis patients. For patients with AVF stenosis, the pressure over the antecedent part of the AVF stenotic lesion will increase if arterial inflow is sufficient. We report a chronic hemodialysis patient who received an angiographic examination for the juxta-anastomosis stenosis of his AVF. A unique feature of a collateral venous branch antecedent to the stenotic lesion was noted, resembling a musical sign as the "eighth note." After percutaneous transluminal angioplasty, the eighth note attenuated markedly at once. Of note, the eighth note sign is not seen frequently, and thus we postulate that the formation of an eighth note sign on the radiocephalic fistula should fulfill the following requirements, including a sufficient arterial inflow, an adjacent collateral branch close enough to the arteriovenous anastomosis, a severe juxta-anastomotic stenotic lesion, and an intact ulnar venous drainage system.

Reverse blood flow as an option in mandibular reconstruction using a two-segment fibula free flap.

Microsurgical reconstruction is currently considered a method of choice for the repair of soft tissue or bony defects in head and neck surgery. This technical note presents the use of a reverse flow technique in mandibular reconstruction with two segments of fibula free flap in a patient with bilateral pseudoarthrosis. In the standard procedure, both segments of the fibula are supplied by one donor vascular pedicle with normal antegrade blood flow. The approach presented here employs reverse flow in the distal segment of the fibula using a venous graft to create two vascular independent free fibula segments. Reverse flow in mandibular reconstruction represents an alternative option to support the success of microsurgical procedures in indicated cases.

The macular structure and blood flow in familial exudative vitreoretinopathy with inner retinal layer persistence / 中华眼底病杂志

Objective:To compared the changes of macular microvascular architecture in early stage familial exudative vitreoretinopathy (FEVR) patients with inner retinal layer (IRL) persistence and without IRL persistence.Methods:A retrospective clinical study. From 2017 to 2022, 94 patients with stage 1 FEVR with or without IRL residue and 45 age- and sex-matched healthy volunteers with 45 eyes (normal control group) who were confirmed by ophthalmology examination in Hangzhou Hospital of Optometry Affiliated to Wenzhou Medical University and Zhejiang Provincial People's Hospital were included in the study. According to whether there was IRL residue, the patients were divided into IRL group and non-IRL group, with 22 patients (22 eyes) and 72 patients (72 eyes), respectively. Best corrected visual acuity (BCVA) and optical coherence tomography angiography (OCTA) were performed in all eyes. Superficial vessel density (SCP) and deep vessel density (DCP) of whole image, fovea and parafovea, the area and perimeter of fovea avascular area (FAZ), A-circularity index (AI, perimeter/standard circle perimeter with equal area) and vessel density around the 300 μm width of the FAZ (FD), central macular thickness (CMT) on macular 3 mm × 3 mm scan on OCTA were measured.Results:SCP and DCP of whole image ( F=10.774, 4.583) and parafovea ( F=10.433, 3.912), CMT ( F=171.940) in IRL group and non-IRL group on macular 3 mm × 3 mm scan on OCTA were significantly lower than that in normal persons ( P<0.05). There were significant differences among three groups of the area of FAZ ( F=4.315), AI ( F=3.413), FD-300 ( F=13.592) ( P<0.05). BCVA were worst in IRL group ( P<0.05). Conclusions:Blood flow density decreased in macular area of FEVR patients. CMT is significantly thicker than normal population. The FAZ area of the foveal IRL residual eyes is small and irregular, with worse BCVA and lower macular blood density.

Relationship between anaerobic work capacity and critical oxygenation in athletes / Relación entre la capacidad de trabajo anaeróbico y la oxigenación crítica en deportistas / Relação entre capacidade de trabalho anaeróbico e oxigenação crítica em atletas

Objective: Anaerobic work capacity (AWC) is understood as the maximum power that the athlete can withstand over time, conditioned by high intensityeffort and it is important to interpret it for the performance improvement. In addition, the muscle oxygen saturation (SmO2) provides information onmuscle metabolism and hemodynamics. Likewise, critical oxygenation (CO) is the highest metabolic rate that results in a fully oxidative energy supplythat reaches a stable state at the substrate level. The main problem is that SmO2 generally offers a traditional laboratory interpretation withoutapplication in field tests, Therefore, the purpose of this study is to provide the use of CO as an indicator of AWC performance in high intensity exercise. Methods: Twenty-two male rugby players participated. Peak torques during an isokinetic fatigue test and muscle oxygen consumption (mVO2) and SmO2in the vastus lateralis were measured. A correlation and multiple regression analysis were applied to find an explanatory prediction model of the AWC. Results: A greater SmO2 amplitude and CO would mean less anaerobic work (r = -0.58 and r=-0.63) and less force production. In addition, CO along withweight (kg) can explain the AWC by 64% during high intensity exercise. Conclusion: The measurement of critical oxygenation is associated with the AWC, so should be considered a performance factor. These parameters couldbe included in NIRS sensors to evaluate muscle metabolism.(AU)

Objetivo: La capacidad de trabajo anaeróbico (AWC) se entiende como la potencia máxima que el deportista puede soportar a lo largo del tiempo,condicionada por un esfuerzo de alta intensidad y es importante interpretarla para la mejora del rendimiento. Además, la saturación de oxígenomuscular (SmO2) proporciona información sobre el metabolismo muscular y la hemodinámica. Asimismo, la oxigenación crítica (OC) es la tasametabólica más alta que da como resultado un suministro de energía completamente oxidativo que alcanza un estado estable a nivel de sustrato. Elprincipal problema es que SmO2 generalmente ofrece una interpretación de laboratorio tradicional sin aplicación en pruebas de campo, por lo tanto, elpropósito de este estudio es proporcionar el uso de OC como indicador del rendimiento de AWC en ejercicio de alta intensidad. Métodos: Participaron 22 jugadores masculinos de rugby. Se midieron los picos máximos después de una prueba de fatiga isocinética y el consumo deoxígeno muscular (mVO2) y SmO2 en el musculo vasto lateral. Se aplicó un análisis de correlación y regresión múltiple para encontrar un modelo depredicción explicativo del AWC. Resultados: Una mayor amplitud de SmO2 y OC supondría un menor trabajo anaeróbico (r = -0,58 y r=-0,63) y una menor producción de fuerza. Además,el CO junto con el peso (kg) pueden explicar el AWC en un 64 % durante el ejercicio de alta intensidad. Conclusión: La medición de la oxigenación crítica está asociada a la AWC, por lo que debe considerarse un factor de rendimiento. Estos parámetrospodrían incluirse en sensores NIRS para valorar el metabolismo muscular.(AU)

Objetivo: A capacidade anaeróbica de trabalho (AWC) é entendida como a potência máxima que o atleta pode suportar ao longo do tempo, condicionadapor um esforço de alta intensidade, sendo importante interpretá-la para melhorar o desempenho. Além disso, a saturação muscular de oxigênio (SmO2)fornece informações sobre o metabolismo muscular e a hemodinâmica. Da mesma forma, a oxigenação crítica (OC) é a taxa metabólica mais alta queresulta em um suprimento de energia totalmente oxidativo atingindo um estado estável no nível do substrato. O principal problema é que o SmO2geralmente oferece uma interpretação laboratorial tradicional sem aplicação em testes de campo, portanto, o objetivo deste estudo é fornecer o uso doCO como indicador de desempenho de AWC em exercícios de alta intensidade. Métodos:Participaram 22 jogadores de rugby do sexo masculino. Foram medidos os picos máximos após um teste de fadiga isocinética e o consumo deoxigênio muscular (mVO2) e SmO2 no músculo vasto lateral. Uma análise de correlação e regressão múltipla foi aplicada para encontrar um modeloexplicativo de predição do AWC. Resultados: Uma maior amplitude de SmO2 e CO implicaria em menor trabalho anaeróbio (r = -0,58 er = -0,63) e menor produção de força. Além disso, oCO junto com o peso (kg) pode explicar a AWC em 64% durante o exercício de alta intensidade. Conclusão: A medida oxigenação crítica prevê AWC, portanto, deve ser considerada um fator de desempenho. Esses parâmetros podem ser incluídos emsensores NIRS para a medição do metabolismo muscular.(AU)

MRI-based pre- and postprandial flow in the mesenteric vasculature of patients with suspected chronic mesenteric ischemia.

PURPOSE: The physiological increase of mesenteric blood flow after a meal is impaired in patients with occlusive chronic mesenteric ischemia (CMI). This principle could be used to develop a highly desired diagnostic test assessing the sufficiency of the collateral mesenteric circulation. This study assesses the potential to identify CMI patients using two-dimensional time-resolved phase-contrast magnetic resonance imaging (2D PC-MRI) flow measurements. METHOD: This prospective cohort study included patients with suspected CMI, based on: typical history, imaging, and functional testing. Cardiac gated 2D PC-MRI flow measurements (expressed as ml/min/kg) were performed in mesenteric arteries and veins during inspiration and expiration, after six hours of fasting and 20, 30, and 40 min after a meal challenge with a high caloric drink. RESULTS: Flow measurements were obtained in 19 patients: 8 CMI and 11 non-CMI. CMI patients showed a significantly smaller increase in postprandial blood flow in the superior mesenteric artery (SMA) at 30 and 40 min (30 min CMI 1.27(0.12-2.44) vs. non-CMI 7.82(6.28-10.90); 40 min CMI 0.30(-0.26-3.16) vs. non-CMI 7.94(6.32-10.90)) and a lower total arterial flow at 40 min (CMI 3.21(-0.72-5.05) vs. non-CMI 9.31(5.58-13.83)). Repeated flow measurements showed normalization of impaired postprandial venous flow after mesenteric artery stenting in one patient. CONCLUSIONS: The significantly lower increase in postprandial mesenteric blood flow in CMI patients confirms the promise of mesenteric blood flow measurements, before and 30-40 min after a meal, as a future diagnostic test to identify CMI patients among patients with a high clinical suspicion of CMI and mesenteric artery stenosis.

Imaging Regional Lung Structure and Function in Small Animals Using Synchrotron Radiation Phase-Contrast and K-Edge Subtraction Computed Tomography.

Synchrotron radiation offers unique properties of coherence, utilized in phase-contrast imaging, and high flux as well as a wide energy spectrum which allow the selection of very narrow energy bands of radiation, used in K-edge subtraction imaging (KES) imaging. These properties extend X-ray computed tomography (CT) capabilities to quantitatively assess lung morphology, and to map regional lung ventilation, perfusion, inflammation, aerosol particle distribution and biomechanical properties, with microscopic spatial resolution. Four-dimensional imaging, allows the investigation of the dynamics of regional lung functional parameters simultaneously with structural deformation of the lung as a function of time. These techniques have proven to be very useful for revealing the regional differences in both lung structure and function which is crucial for better understanding of disease mechanisms as well as for evaluating treatment in small animal models of lung diseases. Here, synchrotron radiation imaging methods are described and examples of their application to the study of disease mechanisms in preclinical animal models are presented.

Effects of Arterial Carbon Dioxide Tension on Cerebral and Somatic Regional Tissue Oxygenation and Blood Flow in Neonates After the Norwood Procedure With Deep Hypothermic Cardiopulmonary Bypass.

Neonates undergoing the Norwood procedure for hypoplastic left heart syndrome are at higher risk of impaired systemic oxygen delivery with resultant brain, kidney, and intestinal ischemic injury, shock, and death. Complex developmental, anatomic, and treatment-related influences on cerebral and renal-somatic circulations make individualized treatment strategies physiologically attractive. Monitoring cerebral and renal circulations with near infrared spectroscopy can help drive rational therapeutic interventions. The primary aim of this study was to describe the differential effects of carbon dioxide tension on cerebral and renal circulations in neonates after the Norwood procedure. Using a prospectively-maintained database of postoperative physiologic and hemodynamic parameters, we analyzed the relationship between postoperative arterial carbon dioxide tension and tissue oxygen saturation and arteriovenous saturation difference in cerebral and renal regions, applying univariate and multivariate multilevel mixed regression techniques. Results were available from 7,644 h of data in 178 patients. Increases in arterial carbon dioxide tension were associated with increased cerebral and decreased renal oxygen saturation. Differential changes in arteriovenous saturation difference explained these effects. The cerebral circulation showed more carbon dioxide sensitivity in the early postoperative period, while sensitivity in the renal circulation increased over time. Multivariate models supported the univariate findings and defined complex time-dependent interactions presented graphically. The cerebral and renal circulations may compete for blood flow with critical limitations of cardiac output. The cerebral and renal-somatic beds have different circulatory control mechanisms that can be manipulated to change the distribution of cardiac output by altering the arterial carbon dioxide tension. Monitoring cerebral and renal circulations with near infrared spectroscopy can provide rational physiologic targets for individualized treatment.

Characterization of Systemic and Regional Hemodynamics and Vascular Dysfunction in Mice with Fecal Induced Peritonitis.

Sepsis is associated with circulatory dysfunction contributing to disturbed blood flow and organ injury. Decreased organ perfusion in sepsis is attributed, in part, to the loss of vasoregulatory mechanisms. Identifying which vascular beds are most susceptible to dysfunction is important for monitoring the recovery of organ function and guiding interventions. This study aimed to investigate the development of vascular dysfunction as sepsis progressed to septic shock. Anesthetized C57Bl/6 mice were instrumented with a fiberoptic pressure sensor in the carotid artery for blood pressure measurements. In subgroups of mice, regional blood flow measurements were taken by positioning a perivascular flow probe around either the left carotid, left renal, or superior mesenteric arteries. Hemodynamic parameters and their responsiveness to bolus doses of vasoactive drugs were recorded prior to and continuously after injection of fecal slurry (1.3 mg/g body weight) for 4 h. Fecal slurry-induced peritonitis reduced mean arterial pressure (62.7 ± 2.4 mmHg vs. 37.5 ± 3.2 mmHg in vehicle and septic mice, respectively), impaired cardiac function, and eventually reduced organ blood flow (71.9%, 66.8%, and 65.1% in the superior mesenteric, renal, and carotid arteries, respectively). The mesenteric vasculature exhibited dysregulation before the renal and carotid arteries, and this underlying dysfunction preceded the blood pressure decline and impaired organ blood flow.

Clinical and Multi-Mode Imaging Features of Eyes With Peripapillary Hyperreflective Ovoid Mass-Like Structures.

PURPOSE: To observe and analyze the clinical and multi-mode imaging features of eyes with PHOMS, and to introduce two cases of PHOMS which underwent multi-mode imaging. METHODS: Retrospective clinical observational study. A total of 26 patients (37 eyes) with hyperreflective structures surrounded by hyporeflective edges around the optic discs who were examined and diagnosed at Shandong Eye Hospital between January 2019 and June 2021 were included in the study. Among these patients, 12 were male and 14 were female. Fifteen were monocular. The average age was 39 years. All patients underwent the following examinations: Best-corrected visual acuity (BCVA), intraocular pressure examinations, slit-lamp anterior segment examinations, indirect ophthalmoscopy, visual field examinations, fundus color photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA). Some of the patients were examined with fundus fluorescein angiography (FFA). Clinical data and imaging characteristics from the OCT, OCTA, and FFA were analyzed retrospectively. RESULTS: We found the hyperreflective structures surrounded by hyporeflective edges around the optic discs in 37 eyes. EDI-OCT results revealed hyperreflective structures surrounded by hyporeflective edges around the optic discs in all eyes. Typical hyperreflexia lesions occurred around the optic disc, located subretinally and above Bruch's membrane. OCTA revealed that the highly reflective perioptic material also had vascular structures. CONCLUSION: EDI-OCT of PHOMS showed hyperreflective structures surrounded by hyporeflective edges around all of the optic discs. Infra-red photography showed temporal hyperreflexia. These characteristics can be seen in a variety of diseases and may be a relatively common feature revealed by EDI-OCT scanning. These characteristics may also be seen in elderly patients as well as children. PHOMS may be found in optic disc drusen (ODD), tilted disc syndrome (TDS), optic neuritis, ischemic optic neuropathy, and in white dot syndromes. Few patients may be developed into macular neovascularization (MNV). In order to improve the accuracy and robustness of the conclusions and provide better clinical guidance, we need to conduct more comprehensive research in the subsequent clinical work.

Synthesis and formulation of [64Cu]Cu-PTSM for PET perfusion imaging in small animal models.

PURPOSE: The [64Cu]Cu-PTSM radiopharmaceutical, pyruvaldehyde bis(N4-methylthiosemicarbazonato)copper(II), is suitable for use in microPET and autoradiographic imaging to assess regional tissue perfusion in small animal models. We report here an approach to synthesis and formulation of the [64Cu]Cu-PTSM radiopharmaceutical at the high concentrations required for use in imaging with rodent models of human disease. METHODS: The [64Cu]Cu-PTSM radiopharmaceutical was prepared at small volumes by addition of the H2PTSM ligand to acetate-buffered [64Cu]copper chloride, followed by solid phase extraction to isolate and purify the product, which was then recovered and formulated in 2-mL normal saline containing 5% ethanol and 5% propylene glycol. RESULTS: The [64Cu]Cu-PTSM radiopharmaceutical has been produced over the range of 0.41-1.85 GBq (11-50 mCi) [64Cu]Cu-PTSM in the 2.0-mL final product volume. Radiochemical purity of the [64Cu]Cu-PTSM radiopharmaceutical product averaged 99.8 ± 0.4% (n = 64), with the final formulated product produced at an 83 ± 5% radiochemical yield. CONCLUSIONS: The approach to [64Cu]Cu-PTSM synthesis and formulation has proven to be reliable and robust, supporting radiopharmaceutical delivery at the high concentrations required for PET studies in mouse and other rodent models.

Clinical value of high-frequency color Doppler ultrasound in the detection of axillary lymph node metastasis in breast cancer / 中国基层医药

Objective:To analyze the clinical value of high-frequency color Doppler ultrasound in the detection of axillary lymph node metastasis in breast cancer.Methods:The clinical data of 60 patients with breast cancer who received treatment in Hangzhou Hospital, Zhejiang Medical & Health Group between March 2017 and March 2019 were retrospectively analyzed. Based on pathological results, 34 patients with breast cancer who had axillary lymph node metastasis were included in the observation group, and 26 patients without axillary lymph node metastasis were included in the control group. Both groups of patients underwent high-frequency color Doppler ultrasound examination. Ultrasound image characteristics, distribution of blood flow within the lymph nodes, and grading of blood flow signals were compared between the two groups, and ultrasound diagnosis results were analyzed.Results:Detection rate of cortical thickening, detection rate of lymph node long-diameter to lymph node short-diameter ratio > 2, detection rate of blurred lymph node borders, and detection rate of calcified foci within lymph nodes in the observation group were 55.9% (19/34), 58.8% (20/34), 61.8% (21/34), 52.9% (18/34), respectively, which were significantly higher than those in the control group [11.5% (3/26), 26.9% (7/26), 19.2% (5/26), 7.7% (2/26), χ2 = 12.48, 6.06, 10.85, 13.57, all P < 0.05]. The percentage of peripheral type blood flow distribution in the observation group was significantly higher than that in the control group and the percentage of portal type blood flow distribution in the observation group was significantly lower than that in the control group (both P < 0.05). The percentage of grade 2 blood flow signal in the observation group was significantly lower than that in control group, and the percentage of grade 3 blood flow signal in the observation group was significantly higher than that in the control group (both P < 0.05). The sensitivity, specificity, misdiagnosis rate and missed diagnosis rate of ultrasound in the detection of axillary lymph node metastasis in breast cancer were 88.2% (30/34), 73.1% (19/26), 26.9% (7/26), and 11.8% (4/34), respectively. Conclusion:High-frequency color Doppler ultrasonography in the detection of breast cancer axillary lymph node metastasis has ideal accuracy, and its diagnostic results are of high reference value.

Correlations between macular microvascular parameters in patients with type 2 diabetes mellitus and urinary albumin creatinine ratio / 中华眼底病杂志

Objective:To observe and analyze the correlation between macular microvascular parameters and urinary albumin to creatinine ratio (UACR) in patients with type 2 diabetes mellitus (T2DM).Methods:A cross-sectional study. From October 2017 to April 2018, 100 eyes of 100 patients (T2DM) and 27 eyes of 27 healthy controls (the control group) were enrolled in Xuzhou First People’s Hospital. All subjects underwent anterior segment examination via slit-lamp biomicroscopy, dilated fundus examination, 7-field fundus photographs, OCT angiography (OCTA), the fasting glucose test, glycosylated hemoglobin (HbA1c), urinary albumin, urinary creatinine and UACR levels determination. Height and weight measurement were taken for calculating body mass index (BMI). Diabetic retinopathy was ruled out by fundoscopic examinations and 7-field fundus photographs in T2DM patients. According to the UACR, patients in the T2DM group were subdivided into A1 group (UACR< 30 mg/g), A2 group (UACR 30-300 mg/g), and A3 group (UACR>300 mg/g), with 38 cases and 38 eyes respectively , 40 cases with 40 eyes, 22 cases with 22 eyes. A 6 mm×6 mm scanning area centered on the macular fovea were scanned for right eye using a frequency domain OCTA instrument, which were divided into three concentric circles centered on the macular fovea by the software automatically. The foveal zone was defined as a circular area measuring 1 mm in diameter, the parafoveal zone was described as a middle circle area measuring 1-3 mm in diameter, and the perifoveal zone was an outer circle area measuring 3-6 mm in diameter. The vessel density of superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular area (FAZ) and perimeter (PERIM), non-circularity index (AI) were measured. The correlation between the macular vessel density, FAZ and UACR was analyzed by Spearman correlation analysis.Results:A1 group, A2 group, A3 group, and normal control group. The macular area SCP and DCP ( F=13.722, 5.644), foveal area ( F=4.607, 4.719), parafoveal area ( H=23.142, F=2.904), the blood flow density of the area around the fovea ( F=12.292, H=10.946), the difference was statistically significant ( P<0.05); with the increase of UACR, the blood flow density of each area of SCP and DCP showed a downward trend. The results of correlation analysis showed that the blood flow density of the whole SCP, parafoveal area, and surrounding area of T2DM patients was negatively correlated with UACR ( r=-0.376, -0.240, -0.364,-0.347, P<0.05). There were no correlation among fasting plasma glucose, HbAlc and UACR ( r=0.179, 0.085, P>0.05). There were no correlation among blood flow density in BMI, SCP foveal area, DCP and UACR (| r|<0.3, P>0.05). Conclusion:The whole, parafovea and perifovea vessel density values of SCP in T2DM eyes without DR are negatively correlated with UACR.

Macular morphology and vascular parameters changes following micro-invasive vitrectomy in patients with severe non-proliferative diabetic retinopathy / 中华眼底病杂志

Objective:To observe the changes of macular morphology and blood flow after minimally invasive vitrectomy (PPV) in patients with severe non-proliferative diabetic retinopathy (sNPDR).Methods:A prospective clinical study. From January 2020 to April 2021, 17 consecutive sNPDR patients with 17 eyes who were diagnosed and received PPV treatment at the Zhongshan Ophthalmic Center of Sun Yat-sen University were included in the study. There were 12 males with 12 eyes and 5 females with 5 eyes; the average age was 55 years old; the average duration of diabetes was 11 years; the average glycosylated hemoglobin was 7.9%. Before the operation and 1, 3, and 6 months after the operation, all the affected eyes underwent best corrected visual acuity (BCVA), standard 7-field fundus color photography, and optical coherence tomography angiography (OCTA). An OCTA instrument was used to scan the macular area of the affected eye with in the range of 3 mm×3 mm to measure the central subfoveal thickness (CST), the thickness of the ganglion cell complex (GCC) in the macular area, the thickness of the retinal nerve fiber layer (RNFL), and the superficial capillary plexus (SCP) vessel density and perfusion density in the macular area, macular avascular zone (FAZ) area, a-circularity index (AI). Before the operation and 6 months after the operation, the least significant difference test was used for the pairwise comparison.Results:Before the operation, 1, 3, and 6 months after the operation, the FAZ area of the macular area were 0.34±0.14, 0.35±0.10, 0.37±0.10, 0.36±0.13 mm 2, respectively; AI were 0.52±0.13, 0.54±0.11, 0.57±0.10, 0.60±0.11; CST was 282.6±66.7, 290.4±70.9, 287.2±67.5, 273.2± 49.6 μm; GCC thickness were 77.1±15.5, 74.3±13.9, 72.6±16.2, 78.5±18.3 μm; the thickness of RNFL was 97.9±13.8, 101.3±14.6, 97.7±12.0, 96.1±11.4 μm, respectively. The overall blood flow density of SCP in the macula were (16.79±1.43)%, (16.71±1.82)%, (17.30±2.25)%, (17.35±1.22)%; the overall perfusion density were 0.32±0.02, 0.32±0.03, 0.33±0.03, 0.33±0.02, respectively. After the operation, the CST increased first and then decreased; the thickness of RNFL increased 1 month after the operation, and then gradually decreased. Comparison of the parameters before and 6 months after the operation showed that the AI improved, and the difference was statistically significant ( P=0.049); the difference in FAZ area and the thickness of CST, GCC, and RNFL was not statistically significant ( P=0.600, 0.694, 0.802, 0.712); There was no statistically significant difference in the retina SCP blood flow density and perfusion density in the macular area ( P=0.347, 0.361). Conclusion:Compared with before surgery, there is no significant change in macular structure and blood flow density in sNPDR patients within 6 months after minimally invasive PPV.

Multimodal imaging features of tamoxifen retinopathy / 中华眼底病杂志

Objective:To observe the multimodal imaging characteristics of tamoxifen retinopathy.Methods:A retrospective case study. From January 2019 to December 2021, 4 patients (8 eyes) with tamoxifen retinopathy diagnosed in Tangshan Eye Hospital were included in the study. All patients were female, with sick binoculus. The age was 59.5±4.6 years. After breast cancer resection, tamoxifen 20 mg/d was taken orally consecutively, including 1, 1, and 2 cases who took tamoxifen orally for 5, 7, and ≥10 years. All eyes were examined by fundus color photography, optical coherence tomography (OCT), OCT angiography (OCTA), fundus fluorescein angiography (FFA), and fundus autofluorescence (AF). The multi-mode image features of the fundus of the affected eyes were observed.Results:The yellow white dot crystal like material deposition in the macular area was observed in all eyes. In fundus AF examination, macular area showed patchy strong AF. FFA examination showed telangiectasia and fluorescein leakage in macular area at late stage. OCT showed that punctate strong reflexes could be seen between the neuroepithelial layers in the macular region with the formation of a space between the neuroepithelial layers, the interruption of the elliptical zone (EZ), and the formation of a hole in the outer lamella including 4, 5 and 3 eyes; The thickness of ganglion cells in macular region decreased in 7 eyes. OCTA showed that the blood flow density of the superficial retinal capillary plexus around the arch ring was decreased, and the retinal venules were dilated in 2 eyes; Deep capillary plexus (DCP) showed telangiectasia.Conclusion:Deposition of yellowish white dot like crystals can be seen in the macular region of tamoxifen retinopathy; dotted strong reflex between neuroepithelial layers, cavity formation, thinning of ganglion cell layer, EZ middle fissure and outer lamellar fissure; DCP capillaries and venules around the arch were dilated; telangiectasia in macular region; flaky strong AF in macular region.