New Fully Automated Preparation of High Apparent Molar Activity 68Ga-FAPI-46 on a Trasis AiO Platform.

A large number of applications for fibroblast activation protein inhibitors (FAPI)-based PET agents have been evaluated in conditions ranging from cancer to non-malignant diseases such as myocardial infarction. In particular, 68Ga-FAPI-46 was reported to have a high specificity and affinity for FAP-expressing cells, a fast and high accumulation in tumor lesions/injuries together with a fast body clearance when investigated in vivo. Due to the increasing interest in the use of the agent both preclinically and clinically, we developed an automated synthesis for the production of 68Ga-FAPI-46 on a Trasis AiO platform. The new synthetic procedure, which included the processing of the generator eluate using a strong cation exchange resin and a final purification step through an HLB followed by a QMA cartridge, yielded 68Ga-FAPI-46 with high radiochemical purity (>98%) and apparent molar activity (271.1 ± 105.6 MBq/nmol). Additionally, the in vitro and in vivo properties of the product were assessed on glioblastoma cells and mouse model. Although developed for the preparation of 68Ga-FAPI-46 for preclinical use, our method can be adapted for clinical production as a reliable alternative to the manual (i.e., cold kit) or modular systems preparations already described in the literature.

Does otosclerosis affect the dimensions of the facial canal and cochlear aquaduct?

PURPOSE: Our aim was to evaluate the relationship of the dimensions of the facial canal (FC) and cochlear aqueduct (CA) in otosclerosis (OS) with the type and severity of OS. METHODS: Two radiologists retrospectively evaluated temporal bone high-resolution computed tomography (HRCT) images obtained from 48 healthy individuals and 94 OS patients between January 2015 and July 2020. In the study group, the CA width, funnel base width, and funnel length, in addition to the FC transverse length, were measured in the axial plane. The CA length was measured in the coronal plane on HRCT images. The FC craniocaudal length was measured in the same plane as the fissula ante fenestram (FAF) in coronal reformatted HRCT images. Grading of OS was based on otosclerotic plaque density and new bone formation extending toward the tympanic cavity at the FAF level. RESULTS: In the OS patients, the CA width and FC craniocaudal and FC transverse diameters were significantly decreased on both sides compared to those in the control group (p < 0.001). In fenestral OS, the FC craniocaudal and transverse widths on both sides were statistically significantly lower than the FC widths in the control group (p < 0.0001). A statistically negative correlation was found in the FC craniocaudal (r = - 0.831/- 0.818) and transverse (r = - 0.742/- 0.750) measurements on both sides in accordance with an increase in the otosclerotic plaque density (p < 0.0001). CONCLUSION: The presence of narrowing in the FC and CA adjacent to the FAF supports the role of autoimmunity theory in the etiology of OS.

Evaluation of the chest computed tomography and hemogram data in patients with COVID-19: the importance of thymus

Background/aim: To investigate the relationship between imaging findings and peripheral blood cell counts of COVID-19 patients and the degree of thymus fat involution of these patients. Materials and methods: Computed tomography (CT) images of 87 patients with COVID-19 positive through RT-PCR testing were evaluated retrospectively by two radiologists. Ground glass densities and other signs of viral pneumonia were recorded, lung involvement was scored quantitatively. The patients thymus fat involution was graded on CT. Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratios (PLR), lymphocyte and platelet counts were calculated. Imaging findings and degrees of thymus fat involution were compared with laboratory data. Results: Quantitative scoring of lung involvement was calculated at mean 6.63 ± 4.70 (1­23) for observer 1 and mean 6.55 ± 4.65 (1­23) for observer 2 (K = 0.824­1.000). Statistical significance was determined between the increase in age and the increase in scores of lung findings (p = 0.003). Lymphocyte count (p = 0.0001) and PLR (p = 0.001) were significantly lower in patients with severe CT involvement. A statistically significantcorrelation was found between increased thymus fat component and presence of COVID-19 lung involvement in CT (r = 0.461). Conclusion: The severity of imaging findings for COVID-19 patients significantly correlates with the degree of fat involution in patients' thymus tissue.

Emissary veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa emissary veins: MR study.

PURPOSE: The aim of this study was to find the prevalence of emissary veins and to compare the visibility of these emissary veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). MATERIALS AND METHODS: All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa emissary veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the emissary veins was compared with the dural venous sinus anatomic variations. p < 0.05 was considered statistically significant. An inter-observer reliability analysis was performed. RESULTS: The prevalence of emissary veins in MRI was found in the right mastoid emissary vein (MEV) 82.7% and left MEV 81.4%. Occipital emissary vein (OEV) was present in 63 patients (28.6%) for the first radiologist (R1), and it was present in 61 patients (27.7%) for the second radiologist (R2) (K = 0.978). A statistically significant correlation was detected between the diameter of the left MEV and gender (p < 0.05) for both radiologists. There was a statistically significant difference between the left MEV and OEV and transverse sinus anatomic variations. CONCLUSION: MR imaging is a noninvasive and irradiating imaging method for detecting posterior fossa major emissary veins, and we recommend using MR imaging for preoperative evaluation of posterior fossa major emissary veins and related dural venous sinuses.

Pancreatic injury due to blunt trauma on CT: does retropancreatic fat tissue reduce the severity of pancreatic injury?

BACKGROUND: Pancreatic injuries from blunt abdominal trauma have a high mortality rate, often accompanied by injuries to adjacent organs. This study aims to investigate the relationship between the size of retropancreatic adipose tissue and the severity of pancreatic and adjacent organ injuries in patients with pancreatic trauma. METHODS: We retrospectively screened computed tomography (CT) images of 34 patients (25 males, nine females, aged 13-69 years) and 34 controls (28 males, six females, aged 15-66 years) who suffered blunt abdominal trauma. The area of adipose tissue located posterior to the pancreatic body was measured in the axial plane for all subjects. The severity of pancreatic injury was assessed in terms of the injury site, the retropancreatic adipose tissue area, and the degree of other organ injuries. RESULTS: Pancreatic injuries were located in the head for 16 patients (23.5%), in the body for four patients (5.9%), and in the tail for 14 patients (20.6%). The retropancreatic fat area was found to be significantly smaller in patients with pancreatic trauma compared to controls (p<0.0001). Furthermore, the ratio of the retropancreatic fat area to the vertebral corpus area differed significantly between patients with and without pancreatic injuries (p=0.014). CONCLUSION: Retropancreatic adipose tissue protects the pancreatic body from the impacts of blunt abdominal trauma. An increased amount of retropancreatic adipose tissue is associated with a reduced rate of pancreatic injury.

Intracranial injection of natural killer cells engineered with a HER2-targeted chimeric antigen receptor in patients with recurrent glioblastoma.

BACKGROUND: Glioblastoma (GB) is incurable at present without established treatment options for recurrent disease. In this phase I first-in-human clinical trial we investigated safety and feasibility of adoptive transfer of clonal chimeric antigen receptor (CAR)-NK cells (NK-92/5.28.z) targeting HER2, which is expressed at elevated levels by a subset of glioblastomas. METHODS: Nine patients with recurrent HER2-positive GB were treated with single doses of 1 × 107, 3 × 107, or 1 × 108 irradiated CAR-NK cells injected into the margins of the surgical cavity during relapse surgery. Imaging at baseline and follow-up, peripheral blood lymphocyte phenotyping and analyses of the immune architecture by multiplex immunohistochemistry and spatial digital profiling were performed. RESULTS: There were no dose-limiting toxicities, and none of the patients developed a cytokine release syndrome or immune effector cell-associated neurotoxicity syndrome. Five patients showed stable disease after relapse surgery and CAR-NK injection that lasted 7 to 37 weeks. Four patients had progressive disease. Pseudoprogression was found at injection sites in 2 patients, suggestive of a treatment-induced immune response. For all patients, median progression-free survival was 7 weeks, and median overall survival was 31 weeks. Furthermore, the level of CD8+ T-cell infiltration in recurrent tumor tissue prior to CAR-NK cell injection positively correlated with time to progression. CONCLUSIONS: Intracranial injection of HER2-targeted CAR-NK cells is feasible and safe in patients with recurrent GB. 1 × 108 NK-92/5.28.z cells was determined as the maximum feasible dose for a subsequent expansion cohort with repetitive local injections of CAR-NK cells.

Diagnostic Performance of Radiology Residents in Thoracic CT Imaging in Emergency Radiology During The COVID-19 Pandemic.

BACKGROUND: During the COVID-19 pandemic, the workload of all radiologists and radiology residents, as well as other clinical physicians, has increased. INTRODUCTION: This study aims to determine the diagnostic performance of radiology residents, who effectively contribute to the diagnosis of COVID-19. METHODS: The thoracic Computed Tomography (CT) images of 135 patients aged 20-83 diagnosed with COVID-19 were evaluated retrospectively by five radiology residents and a radiologist with 10 years of experience. The diagnostic performance of the radiology residents in evaluating COVID-19 was assessed according to their year of residency and the patients' age and gender. Receiver Operating Characteristic (ROC) curve analysis was performed to determine the sensitivity and specificity of radiology residents. RESULTS: The radiology residents' performance in determining COVID-19 using CT findings was evaluated as follows: sensitivity 97.22%, specificity 88.89%, positive predictive value 90.91%, negative predictive value 96.55%, and accuracy 93.33%. According to the year of residency, the sensitivity and specificity of the radiology residents in determining COVID-19 using CT images were between 92.3% and 100%, and 71.43% and 100%, respectively. CONCLUSION: The high sensitivity and specificity of radiology residents in evaluating thoracic CT images for COVID-19 diagnosis indicate that radiologists are as important as clinical physicians in the diagnosis of COVID-19.

Efficiency of Fat Suppression in T1-Weighted Inner Ear Magnetic Resonance Imaging: Multipoint Dixon Method Versus Hybrid Techniques.

BACKGROUND: Temporal bone is a region where fat suppression is difficult due to the inhomogeneity of various structures with different molecular properties. INTRODUCTION: We aimed to determine the most effective fat suppression sequence in order to increase the visibility of the inner ear region. MATERIALS AND METHODS: The hybrid techniques and T1-Weighted mDIXON images of 40 patients with Magnetic Resonance (MR) imaging of the inner ear were prospectively compared by two experienced radiologists in terms of fat suppression efficacy. In all fat-suppressed sequences, the Signal to Noise Ratio (SNR), the spinal cord signal intensity / mean fat signal intensity ratio and spinal cord signal to noise ratio were calculated. The suppression efficacy of MR techniques for fat areas in the inner ear was visually graded. RESULTS: Qualitative assessment of image quality due to fat suppression in the inner ear was made; the Dixon technique performed significantly better than SPAIR and SPIR techniques (p<0.0001). The mean signal intensity of the inner ear fat and SNR for the Dixon technique were significantly lower than that for SPIR and SPAIR techniques (p<0.0001). Inter-observer agreement regarding the assessment of the inner ear fat, mean signal intensity values and mean SNR values for fat suppression techniques was significant. CONCLUSION: The Dixon technique exhibited higher image quality and fat suppression efficiency than the hybrid techniques in the MR imaging of the inner ear.

Sparsity of dendritic cells and cytotoxic T cells in tumor microenvironment may lead to recurrence in basal cell carcinoma.

BACKGROUND: Antitumor immune response affects tumor growth. The effect of antitumor immune response on recurrence has been poorly studied in basal cell carcinoma (BCC). OBJECTIVES: To investigate the effects of the peritumoral immune infiltrate on BCC recurrence. METHODS: A total of 30 BCC patients without recurrence and 29 BCC patients with recurrence were included in this retrospective study. Non-recurrent tumor samples as well as primary and recurrent tumor samples from the recurrent group were stained immunohistochemically with anti-CD4, CD8, CD25, FOXP3, CD68, CD163, and CD1a antibodies. Immune infiltrates were semiquantitatively evaluated. RESULTS: BCC tumor microenvironment was rich in CD4+ cells. CD163 expression was higher than CD68. In primary tumors of the recurrent group, CD8 expression was significantly lower than CD4 expression. CD1a expression was lower in primary tumors of the recurrent group than in nonrecurrent tumors. CONCLUSIONS: Our results suggest the existence of an immunosuppressive microenvironment in BCC. Lower CD8+ T-cell numbers and sparsity of dendritic cells in primary tumors of recurrent patients suggest further immunosuppression in the tumor microenvironment and an increase in recurrence risk. This is the first study that evaluates and compares tumor immune microenvironments of primary and recurrent BCC lesions with several markers and investigates the role of antitumor immunity on BCC recurrence.

Multiparametric MRI Evaluation of Developmental Venous Anomalies in the Brain: Association with Signal Changes on FLAIR in Patients with Multiple Sclerosis.

BACKGROUND: Developmental venous anomalies (DVAs) can be determined on magnetic resonance imaging (MRI), and they may be associated with multiple sclerosis (MS) lesions. PURPOSE: The objective was to evaluate the MRI findings of DVAs in the brain, to compare the prevalence of them between MS patients and control subjects, and to investigate the correlation of DVA-associated fluid-attenuated inversion recovery (FLAIR) hyperintensities and MRI-derived parameters between MS patients and control subjects having DVA. METHODS: Total 160 patients with a mean age of 45 ± 16 years who underwent multiparametric MRI including susceptibility-weighted imaging (SWI), diffusion-weighted imaging, 3D FLAIR, and contrast-enhanced imaging were included in this retrospective study. First, the presence of DVA was compared between the MS and control groups using the Chi-square test. Then, among the subjects having DVA, age, gender, and MRI-derived parameters such as the signal increase of DVA on FLAIR, location, and drainage of DVA were compared between the MS and control groups using Chi-square test. RESULTS: The presence of DVA did not differ between the MS and control groups (P = 0.828). Signal increase around DVA on FLAIR (P = 0.03) and the age of less than 45 years demonstrated a significant correlation with MS group (P = 0.022). CONCLUSION: In our study, DVAs were effectively detected using SWI and 3D contrast-enhanced T1-weighted imaging on MRI. The signal increase of DVA was better revealed on 3D FLAIR on MRI, and it was the only significant MRI-derived parameter in patients with MS.

Extranodal lymphoma of the head and neck: a pictorial essay.

Primary extranodal lymphoma is defined as a lymphoma at a solitary extranodal site, with or without involvement of the lymph nodes. The clinical and radiological features of extranodal lymphoma have been documented in recent studies. In this pictorial essay, we reviewed imaging findings of extranodal lymphoma in the head and neck region.

Linfoma extranodal primário é definido como um sítio extranodal solitário de linfoma, com ou sem envolvimento dos gânglios linfáticos. As características clínicas e radiológicas do linfoma extranodal foram documentadas em estudos recentes. Neste ensaio revisamos os achados de imagem do linfoma extranodal da região da cabeça e pescoço.

Quantitative Third Harmonic Generation Microscopy for Assessment of Glioma in Human Brain Tissue.

Distinguishing tumors from normal brain cells is important but challenging in glioma surgery due to the lack of clear interfaces between the two. The ability of label-free third harmonic generation (THG) microscopy in combination with automated image analysis to quantitatively detect glioma infiltration in fresh, unprocessed tissue in real time is assessed. The THG images reveal increased cellularity in grades II-IV glioma samples from 23 patients, as confirmed by subsequent hematoxylin and eosin histology. An automated image quantification workflow is presented for quantitative assessment of the imaged cellularity as a reflection of the degree of glioma invasion. The cellularity is validated in three ways: 1) Quantitative comparison of THG imaging with fluorescence microscopy of nucleus-stained samples demonstrates that THG reflects the true tissue cellularity. 2) Thresholding of THG cellularity differentiates normal brain from glioma infiltration, with 96.6% sensitivity and 95.5% specificity, in nearly perfect (93%) agreement with pathologists. 3) In one patient, a good correlation between THG cellularity and preoperative magnetic resonance and positron emission tomography imaging is demonstrated. In conclusion, quantitative real-time THG microscopy accurately assesses glioma infiltration in ex vivo human brain samples, and therefore holds strong potential for improving the accuracy of surgical resection.

Extranodal lymphoma of the head and neck: a pictorial essay / Linfoma extranodal da cabeça e pescoço: ensaio iconográfico

Abstract Primary extranodal lymphoma is defined as a lymphoma at a solitary extranodal site, with or without involvement of the lymph nodes. The clinical and radiological features of extranodal lymphoma have been documented in recent studies. In this pictorial essay, we reviewed imaging findings of extranodal lymphoma in the head and neck region.

Resumo Linfoma extranodal primário é definido como um sítio extranodal solitário de linfoma, com ou sem envolvimento dos gânglios linfáticos. As características clínicas e radiológicas do linfoma extranodal foram documentadas em estudos recentes. Neste ensaio revisamos os achados de imagem do linfoma extranodal da região da cabeça e pescoço.

Renal diffusion-weighted imaging in diabetic nephropathy: correlation with clinical stages of disease.

PURPOSE: We aimed to assess the correlation between renal apparent diffusion coefficient (ADC) values measured by diffusion-weighted imaging (DWI) and the clinical stages of diabetic nephropathy. MATERIALS AND METHODS: DWI (b value, 0 and 600 s/mm2) was performed in 78 patients with clinically confirmed diabetic nephropathy (study group) and 22 volunteers without diabetes mellitus or any renal disease (control group). The mean ADCs were calculated from multiple region-of-interest circles positioned in the renal cortex. Diabetic nephropathy was clinically categorized into five stages based on the values of urinary albumin excretion and glomerular filtration rate (GFR). RESULTS: Mean renal ADC values of patients with stage 3 or 4 disease were significantly lower than those in patients with stage 1 or 2 disease and the control group (P < 0.001). ADC values of patients with stage 5 disease were significantly lower than those in patients with stage 4 (P = 0.003), stage 3 (P = 0.020), stages 2 and 1, and the control group (P < 0.001). Significant correlations were found between mean renal ADC values and clinical stages of diabetic nephropathy (r=-0.751, P < 0.001), between mean renal ADC values and estimated GFR values (r=0.642, P < 0.001), and between mean renal ADC values and urinary albumin excretion (r=-0.419, P < 0.001). CONCLUSION: Renal ADC values show a significant correlation with clinical stages of diabetic nephropathy. As a relatively simple and noninvasive tool without contrast media administration, renal quantitative DWI may potentially play a role in making clinical decisions in the follow-up of diabetic patients.

Surgical termination of pregnancy: evaluation of 14,903 cases.

OBJECTIVE: To evaluate the demographic and clinical characteristics of patients who underwent surgical termination of pregnancy and to assess the efficacy of the termination methods. MATERIALS AND METHODS: This retrospective study was carried out on 14,903 healthy women who had intrauterine pregnancy of