Current Medical Imaging - Volume 18, Issue 4, 2022

Purpose: This review aimed to summarize the available literature on the clinical application of [¹⁸F] FLT PET imaging in primary brain tumours. Methods: A comprehensive search strategy based on Pubmed/Medline, Scopus, Web of Science, Cochrane Library, Google Scholar, and the Embase databases was carried on using the following search string: ('3` Fluorothymidine'/exp OR 'FLT' OR '[81F]-FLT' OR '[¹⁸F] Fluorothymidine') AND ('pet'/exp OR 'pet' OR 'positron emission tomography') AND ('glioma'/exp OR 'glioma' OR 'brain tumour'/exp OR 'brain tumour’). The search was updated till March 2021 and only articles in English and studies investigating the clinical applications of [¹⁸F] FLT PET and PET/CT in primary brain tumours were considered eligible for inclusion. Results: The literature search ultimately yielded 52 studies included in the systematic review, with main results as follows: a) the uptake of [¹⁸F] FLT may guide stereotactic biopsy but does not discriminate between grade II and III glioma. b) [¹⁸F] FLT uptake and texture parameters correlate with overall survival (OS) in newly diagnosed gliomas. c) In patients with recurrent glioma, proliferative volume (PV) and tumour-to-normal brain (T/N) uptake ratio are independent predictors of survival. d) Patients demonstrating response to therapy at [¹⁸F] FLT PET scan show longer OS compared to non-responders. e) [¹⁸F] FLT PET demonstrated good performance in discriminating tumour recurrence from radionecrosis. However, controversial results exist in comparative literature examining the performance of [¹⁸F] FLT vs. other radiotracers in the assessment of recurrence. Conclusion: [¹⁸F] FLT PET imaging has demonstrated potential benefits for grading, diagnostic and prognostic purposes, despite the small sample size studies due to the relatively low availability of the radiotracer.

Objective: The objective of the study was to investigate the consequences of using CArm Cone-Beam computed Tomography (CBCT) on super-selective catheterization of Hepatic Artery (HA) branches during chemoembolization of hepatocellular carcinoma. Methods: Two groups of patients were created according to the dates of their treatment sessions. Group A and Group B included patients who had their treatment sessions in 2004 - 2005 and 2008 - 2010, respectively. The sessions performed in 2006 and 2007 were excluded to allow for the adoption and incorporation of CBCT imaging into clinical practice. All chemoembolized HA branches were categorized according to selection order (0-1, 2, or ≥3). Other procedure variables were documented. Results: A total of 58 and 183 sessions were included in Groups A and B, respectively, for 144 patients. C-arm CBCT was used in 2 (3%) sessions and 142 (78%) sessions in groups A and B, respectively. The average number of vessels treated was significantly higher in group B (1.8) compared to group A (1.3) (P < .0001). A shift to an increased selection order in group B (0-1, 44 [24%]; 2, 85 [46%]; ≥3, 54 [30%]) was more significant (P = .0004) than that in group A (0-1, 32 [55%]; 2, 18 [31%]; ≥3, 8 [14%]). The average duration of the procedure was significantly longer in group B (P = .0002). Conclusion: Using C-arm CBCT during chemoembolization has a positive impact on increasing the number and order of HA selected and chemoembolized. This comes at the expense of an increase in the duration of the procedure.

Background: Computed tomography (CT) evaluation systematics has become necessary to eliminate the difference of opinion among radiologists in evaluating COVID-19 CT findings. Introduction: The objectives of this study were to evaluate the efficiency of CO-RADS scoring system in our patients with COVID-19 as well as to examine its correlation with clinical and laboratory findings. Methods: The CO-RADS category of all patients included in the study was determined by a radiologist who did not know the rtRT-PCR test result of the patients, according to the Covid-19 reporting and data system of Mathias Prokop et al. Results: A total of 1338 patients were included. CT findings were positive in 66.3%, with a mean CO-RADS score of 3,4 ± 1,7. 444 (33.1%) of the patients were in the CO-RADS 1-2, 894 (66.9%) were in the CO-RADS 3-5 group. There were positive correlations between CO-RADS score and age, CMI, hypertension, diabetes mellitus, chronic pulmonary diseases presence of symptoms, symptom duration, presence of cough, shortness of breath, malaise, CRP, and LDH, while CORADS score was negatively correlated with lymphocyte count. The results of the ROC analysis suggested that those with age ≥40 years, symptom duration >2 days, CMI score >1 and/or comorbid conditions were more likely to have a CO-RADS score of 3-5. Conclusion: The CO-RADS classification system is a CT findings assessment system that can be used to diagnose COVID-19 in patients with symptoms of cough, shortness of breath, myalgia and fatigue for more than two days.

Background: Image registration is the process of aligning two or more images in a single coordinate. Nowadays, medical image registration plays a significant role in computer-assisted disease diagnosis, treatment, and surgery. The different modalities available in the medical image make medical image registration an essential step in Computer Assisted Diagnosis (CAD), Computer- Aided Therapy (CAT) and Computer-Assisted Surgery (CAS). Problem Definition: Recently, many learning-based methods were employed for disease detection and classification, but those methods were not suitable for real-time due to delayed response and the need for pre-alignment and labeling. Methods: The proposed research constructed a deep learning model with Rigid transform and B-Spline transform for medical image registration for an automatic brain tumour finding. The proposed research consists of two steps. The first step uses Rigid transformation based Convolutional Neural Network and the second step uses B-Spline transform-based Convolutional Neural Network. The model is trained and tested with 3624 MR (Magnetic Resonance) images to assess the performance. The researchers believe that MR images help in the success of the treatment of patients with brain tumour. Results: The result of the proposed method is compared with the Rigid Convolutional Neural Network (CNN), Rigid CNN + Thin-Plat Spline (TPS), Affine CNN, Voxel morph, ADMIR (Affine and Deformable Medical Image Registration) and ANT(Advanced Normalization Tools) using DICE score, Average Symmetric surface Distance (ASD), and Hausdorff distance. Conclusion: The RBCNN model will help the physician to automatically detect and classify the brain tumor quickly (18 Sec) and efficiently without doing pre-alignment and labeling.

Objective: To examine the relation between perirenal fat volume, which is one of the visceral fat measurements, and kidney stones. Methods: 169 patients admitted to our clinic between January 2018 and May 2021 were included in the study. The patients were divided into 2 groups as Control Group and Unilateral Kidney Stone Group (88 patients with unilateral kidney stones). Contrast-enhanced abdominal computed tomography scans were used to measure perirenal fat volume and the results were transferred to workstations. The total perirenal fat volumes in the bilateral kidneys of patients were compared between the two groups. The perirenal fat volume in stone-bearing and non-stone bearing kidneys of patients were also compared. Results: The total perirenal fat volume was higher in the Unilateral Kidney Stone Group than in the other groups and the perirenal fat volume of the patients in this group was higher in the stone bearing kidney (295.6±164.4cm³) than in the non-stone bearing kidney (273.1±179.6cm³). In the ROC analysis, it was concluded that total perirenal fat volume>387cm³ increased the risk of kidney stones. Presence of hypertension, presence of hyperlipidemia and total perirenal fat volume>387cm³ were found to be independent risk factors for the presence of kidney stones. Conclusion: Perirenal fat volume is higher in stone bearing kidneys compared to non-stone bearing kidneys. Therefore, stone formation in a kidney is directly related to the perirenal fat volume of that kidney. Also, total perirenal fat volume>387cm³ increases the risk of kidney stones independently of body mass index, and predicts it better.

Background: The therapeutic approaches of differentiated thyroid carcinoma (DTC) are surgery, ablation therapy with the postoperative use of radioiodine-131 (¹³¹I), and thyroid-stimulating hormone (TSH) suppression therapy. After the surgical therapy, the patient should be assessed for remnants/metastases. Objective: The purpose of this research was to investigate the role of technetium-^99m-methoxyisobutylisonitrile (^99mTc-MIBI) single photon emission computed tomography/computed tomography (SPECT/CT) in the postoperative management of patients with DTC. Methods: :The study comprised 22 DTC patients (13 women, 9 men; mean age 46.55 ± 13.27 y) who underwent a total thyroidectomy previously. All patients were investigated for thyroid remnants/ metastases by^99mTc-MIBI SPECT/CT, posttherapy ¹³¹I whole-body scan (WBS) and ultrasound (US). Serum TSH, thyroglobulin and anti-Tg antibody levels were measured. Results of imaging modalities and laboratory measurements were compared with each other. Results: ^99mTc-MIBI SPECT/CT, ¹³¹I WBS and US respectively demonstrated thyroid remnants in 15 (68.18%), 22 (100%) and 14 (63.63%) of all patients and metastatic lymph nodes in 8 (100%), 6 (75%) and 6 (75%) of the 8 patients with lymph node metastases.^99mTc-MIBI SPECT/CT also demonstrated lung metastases in 2 patients (9.09% of all patients). The same result was obtained with ¹³¹I WBS. Conclusion: The findings of this study show that ^99mTc-MIBI SPECT/CT can be effective for detecting metastases in patients with DTC who underwent surgery prior to ¹³¹I therapy.

Aims: Early detection of breast cancer has reduced many deaths. Earlier CAD systems used to be the second opinion for radiologists and clinicians. Machine learning and deep learning have brought tremendous changes in medical diagnosis and imagining. Background: Breast cancer is the most commonly occurring cancer in women and it is the second most common cancer overall. According to the 2018 statistics, there were over 2million cases all over the world. Belgium and Luxembourg have the highest rate of cancer. Objective: A method for breast cancer detection has been proposed using Ensemble learning. 2- class and 8-class classification is performed. Methods: To deal with imbalance classification, the authors have proposed an ensemble of pretrained models. Results: 98.5% training accuracy and 89% of test accuracy are achieved on 8-class classification. Moreover, 99.1% and 98% train and test accuracy are achieved on 2 class classification. Conclusion: it is found that there are high misclassifications in class DC when compared to the other classes, this is due to the imbalance in the dataset. In the future, one can increase the size of the datasets or use different methods. In implement this research work, authors have used 2 Nvidia Tesla V100 GPU’s in google cloud platform.

Background: We report a case of a 23-year-old man with a solitary fibrous tumor of the great omentum who presented clinically as a case of dull abdominal pain. Case Presentation: Solitary fibrous tumor normally occurs in the visceral pleura. Extrathoracic solitary fibrous tumor is rare, especially those from the great omentum, with approximately 31 cases reported in the literature. Conclusion: After reviewing and summarizing the imaging findings of 31 cases of solitary fibrous tumor of the greater omentum, we considered that the characteristic findings can provide a reliable basis for preoperative diagnosis.

Background: Epithelial tumors are the most common subgroup and are seen in 60-70% of all ovarian tumors. Serous cystadenoma and mucinous cystadenoma are the most common benign epithelial tumors. Serous cystadenomas are ovarian tumors with the highest bilateral incidence. The coexistence of tumors with different histopathology in the ovaries is extremely rare and has only been reported in a few cases in the literature. We present a case of bilateral ovarian tumor that was diagnosed as serous and mucinous cystadenoma after laparoscopic surgery. Case Report: A 45-year-old female patient was admitted to our center with swelling in the pelvic region and pain in the left lumbar region. US imaging showed a cystic lesion in the right adnexal area, 4x2 cm in size, well-circumscribed, containing a few thin septa, and a low echo fluid content. A cystic lesion with 6x4cm sized multilocular, well-circumscribed, slightly high echo fluid content was observed in the left adnexal area. On CT, a complex cystic lesion measuring 6x4cm was observed in the left adnexal area, pushing the left ureter laterally and causing the hydroureter. In addition, a 4x2 cm cystic lesion was observed in the right adnexal area and hydroureter was observed on the right side proximal to this lesion. Both lesions were removed by surgery. On histopathologic examination, the left-sided cystic lesion was diagnosed as mucinous cystadenoma, and the right-sided cystic lesion was diagnosed as serous cystadenoma. Conclusion: The coexistence of different ovarian tumor subtypes is rare. In this article, we presented a case in which serous and mucinous cystadenoma lesions were seen together for the fourth time in the literature, according to our knowledge.

Background: Leishmaniasis is caused by protozoans that depend on female phlebotomine sandflies as vectors. The natural habitat of these sandflies is changing due to climatic changes, affecting the immunocompromised population, as more patients get immunocompromised due to cancer therapy in the present time. Case Report: We report the case of a 72-year-old patient with melanoma in whom we found visceral leishmaniasis mimicking hepatic metastasis in routine FDG-PET/CT. The patient was hospitalised due to fever and pancytopenia in the general hospital Steyr. The diagnosis was made by biopsy of the iliac crest with cytological study and polymerase chain reaction. After treatment with amphotericin B, the patient recovered and tests became negative, including FDG-PET/CT. Because of climate change and the increasing use of immunomodulatory medication, our awareness of such findings should grow. Conclusion: New pitfalls in diagnosis and surveillance of cancer patients because of altered environmental conditions and immunocompromised patients have to be taken into account.

Background: Clinically, the recurrent artery of the Heubner (RAH) aneurysm is extremely rare, commonly presents with subarachnoid hemorrhage (SAH). Case Report: A 73-year-old man with a known moyamoya disease was presented as caudate hemorrhage attributable to an incidental flow aneurysm distal on the right RAH, which was managed conservatively after an unsuccessful endovascular attempt. Unfortunately, the patient died five weeks after hospital discharge because of the re-rupture of the aneurysm. To the best of our knowledge, the RAH aneurysm manifesting as caudate hemorrhage without SAH has not previously been reported. Conclusion: This case highlights that the RAH aneurysm masquerading as caudate hemorrhage without SAH is exceedingly rare but can be encountered, representing a diagnostic and therapeutic challenge, and should be considered in the differential diagnosis. Moreover, early identifying and then eliminating such vascular anomaly if possible is of importance to prevent fatal hemorrhage.

Background: Orbital metastasis of breast cancer is an unusual condition, especially in the absence of a previous diagnosis of primary breast cancer. The main MRI findings in patients with orbital metastasis are retroorbital soft tissue with thickening of extraocular muscles. Paradoxical enophthalmos secondary to fibrosis can be seen. Case Report: In this case report, we present a 75-year-old female patient with left eye pain and blurred vision and retraction. Although there was no evidence of malignancy in the biopsy of the orbita; since the patient's complaints continued despite idiopathic pseudotumor treatment, mammography was recommended to rule out the possibility of breast cancer metastasis. Her mammography revealed a suspicious lesion in the left breast and proved to be pleomorphic invasive lobular cancer. Conclusion: Breast cancer metastasis should be kept in mind in women with pseudotumor -like the involvement of the orbita.

Background: Kimura disease is a rare inflammatory condition classically manifested as painless subcutaneous nodules in the head and neck region and associated with regional cervical lymphadenopathy and salivary gland involvement. Objective: The purpose of this report is to illustrate the diagnostic difficulty due to its rarity and non-specific clinical presentation. Case Presentation: We present a case of Kimura disease with bilateral eyelid swelling, parotid involvement, and cervical lymphadenopathy in a young boy. Computed Tomography (CT) showed ill- defined enhancing masses in both upper eyelids with lacrimal gland infiltration, multiple nodular lesions in both parotid glands, and bilateral enlargement of cervical nodes. After several multidisciplinary discussions and trials of medications, Kimura's disease was finally confirmed by histology examination. Conclusion: In conclusion, a rare disease such as Kimura must be considered earlier if the patient is not responding to the treatment.

Background: Lung transplantation might be a viable alternative for patients with irreversible lung injury secondary to coronavirus disease 2019 (COVID-19). Here, we describe two patients with end-stage COVID-19 that received lung transplantations, the clinical-radiologic manifestations of postoperative complications, and the imaging features of allograft rejection. Case Presentation: In case 1, a 66-year-old woman presented severe hypoxia after lung transplantation. Chest imaging revealed diffuse homogeneous infiltration in the donor's lung. Dramatic resolution of the imaging abnormalities after intravenous administration of methylprednisolone favored a diagnosis of hyperacute rejection. The second is a 70-year-old man who was infected with bacterial postoperatively. During the empiric antibiotic therapy, chest CT showed newly developed groundglass opacities with septal thickening, suggesting a diagnosis of acute rejection. High-dose corticosteroids therapy was initiated, and the patient recovered gradually. Conclusion: This is the first report describing postoperative complications of lung transplantation in patients with advanced COVID-19. We presumed that imaging procedures could be a useful tool in early detecting lung transplant complications and selecting specific interventions for patients with COVID-19.