Current Medical Imaging - Volume 18, Issue 10, 2022

Radiological assessments of the small and large bowel are essential in daily clinical practice. Over X-ray plain films and ultrasound, cross-sectional techniques are considered the most comprehensive imaging modalities. "Cross-sectional techniques" refers to CT and MRI, as stated in the following sentence. In fact, computed tomography and magnetic resonance imaging take great advantage of the three-dimensional appraisal and the extensive evaluation of the abdominal cavity, allowing intestinal evaluation as well as detection of extra-intestinal findings. In this context, the chief advantage of computed tomography is the fast scan time, which is crucial for emergency cases. Nonetheless, it is undeniably impaired using ionizing radiation. As the awareness of radiation exposure is a topic of increasing importance, magnetic resonance imaging is not only becoming a mere alternative but also a primary imaging technique used in assessing intestinal diseases. Specifically, the evaluation of the large bowel through MRI can still be considered relatively uncharted territory. Although it has demonstrated superior accuracy in the assessment of some clinical entities from inflammatory bowel disease to rectal carcinoma, its role needs to be consolidated in many other conditions. Moreover, different technical methods can be applied for colonic evaluation depending on the specific disease and segment involved. This article aims to provide a thorough overview of the techniques that can be utilized in the evaluation of the large bowel and a discussion on the major findings in different colonic pathologies of primary interest.

Ultrasound is one of the most widely utilized imaging tools in clinical practice with the advantages of noninvasive nature and ease of use. However, ultrasound examinations have low reproducibility and considerable heterogeneity due to the variability of operators, scanners, and patients. Artificial Intelligence (AI)-assisted ultrasound has advanced in recent years, bringing it closer to routine clinical use. The combination of AI with ultrasound has opened up a world of possibilities for increasing work productivity and precision diagnostics. In this article, we describe AI strategies in ultrasound, from current opportunities, constraints to potential options for AI-assisted ultrasound.

Objectives: This study aims to investigate the efficacy of abbreviated breast magnetic resonance imaging (MRI) in neoadjuvant chemotherapy (NAC) response evaluation. Methods: MR images of 50 locally advanced breast cancer patients who underwent standard protocol (SP) breast MRI before and after NAC were re-evaluated retrospectively. Abbreviated protocol (AP) was obtained by extracting images from SP and then evaluating them in a separate session. Protocols were compared with the histological findings after surgery as the reference standard. Results: A statistically significant difference was found between the two protocols in response evaluation by the McNemar test (p=0.018). However, the Kappa value was 0.62 (p<0.001), which indicates substantial agreement. No statistically significant differences were found between the two protocols (AP and SP) and pathological results in the McNemar test (p=0.12, p=0.60, respectively). Kappa values were 0.48 (p<0.001) and 0.60 (p<0.001), respectively, which indicates moderate agreement for both protocols with higher values by SP evaluation. The residual maximum median diameters were smaller than the pathology, with both protocols (p<0.001). Conclusion: Despite the statistical differences, there was a significant correlation in response evaluation between the two protocols. The pathological results were moderately correlated with both protocols, with SP slightly higher. However, the residual maximum median diameters were smaller than the pathology with both protocols. These results may limit the use of AP in evaluating the local extent of the tumor, especially in patients who will undergo breast-conserving surgery.

Background: The prediction of pathological responses for locally advanced rectal cancer using magnetic resonance imaging (MRI) after neoadjuvant chemoradiotherapy (CRT) is a challenging task for radiologists, as residual tumor cells can be mistaken for fibrosis. Texture analysis of MR images has been proposed to understand the underlying pathology. Objective: This study aimed to assess the responses of lesions to CRT in patients with locally advanced rectal cancer using the first-order textural features of MRI T2-weighted imaging (T2-WI) and apparent diffusion coefficient (ADC) maps. Methods: Forty-four patients with locally advanced rectal cancer (median age: 57 years) who underwent MRI before and after CRT were enrolled in this retrospective study. The first-order textural parameters of tumors on T2-WI and ADC maps were extracted. The textural features of lesions in pathologic complete responders were compared to partial responders using Student’s t- or Mann–Whitney U tests. A comparison of textural features before and after CRT for each group was performed using the Wilcoxon rank sum test. Receiver operating characteristic curves were calculated to detect the diagnostic performance of the ADC. Results: Of the 44 patients evaluated, 22 (50%) were placed in a partial response group and 50% were placed in a complete response group. The ADC changes of the complete responders were statistically more significant than those of the partial responders (P = 0.002). Pathologic total response was predicted with an ADC cut-off of 1310 x 10^-6 mm²/s, with a sensitivity of 72%, a specificity of 77%, and an accuracy of 78.1% after neoadjuvant CRT. The skewness of the T2-WI before and after neoadjuvant CRT showed a significant difference in the complete response group compared to the partial response group (P = 0.001 for complete responders vs. P = 0.482 for partial responders). Also, relative T2-WI signal intensity in the complete response group was statistically lower than that of the partial response group after neoadjuvant CRT (P = 0.006). Conclusion: As a result of the conversion of tumor cells to fibrosis, the skewness of the T2-WI before and after neoadjuvant CRT was statistically different in the complete response group compared to the partial response group, and the complete response group showed statistically lower relative T2-WI signal intensity than the partial response group after neoadjuvant CRT. Additionally, the ADC cut-off value of 1310 × 10^-6 mm²/s could be used as a marker for a complete response along with absolute ADC value changes within this dataset.

Background and Objective: Differentiating non-small cell lung cancer (NSCLC) from small cell lung cancer (SCLC) remains a substantial challenge. This study aimed at evaluating the performance of dual-layer spectral detector CT (DLCT) in differentiating NSCLC from SCLC. Methods: Spectral images of 247 cancer patients confirmed by pathology were retrospectively analyzed in both the arterial phase (AP) and the venous phase (VP), including 197 cases of NSCLC and 50 cases of SCLC. Effective atomic number (Z-eff), Spectral CT-Mono Energetic (MonoE [40keV∼90keV]), iodine density (ID) and thoracic aorta iodine density (IDaorta) in contrast-enhanced images were measured and compared between the SCLC and NSCLC subgroups of tumors. The slope of the spectral curve (λ, interval of 10 keV) and normalized iodine density (NID) were also calculated between the SCLC and NSCLC. Through the statistical analysis, the diagnostic efficiency of each spectral parameter was calculated, and the difference in their efficiency was analyzed. Results: Both in NSCLS and SCLC, all parameters in VP were significantly higher than those in AP (p<0.001), except for λ90. There were significant differences in all spectral parameters between NSCLS and SCLC, both in AP and VP (p < 0.001). Except for VP-λ90, there was no significant difference in ROC curves of all spectral parameters. VP-NID exhibited the best diagnostic performance with an AUC value of 0.917 (95%[CI]: 0.870~0.965), sensitivity and specificity of 92.9% and 80%, and a diagnostic threshold of 0.217. Conclusion: All parameters of DLCT have high diagnostic efficiency in differentiating NSCLC from SCLC except for VP-λ90, and VP-NID has the highest diagnostic efficiency.

Background: Pancreatic cancer is mostly diagnosed in advanced stages, and treatment results are not satisfactory. L3 skeletal muscle index (SMI) has emerged as a prognostic factor in pancreatic cancer patients. We aimed to assess the association between sarcopenia and overall survival in patients with pancreatic cancer in this study. Methods: Patients who were admitted to the Department of Oncology between March 2012 and December 2019 and diagnosed with pancreatic cancer were evaluated. The computerized tomography images and laboratory parameters of a total of 115 patients were included in this retrospective singlecenter study. We defined sarcopenia as an SMI <43,56 cm²/m² for females and <56,44 cm²/m² for males using the receiver operating characteristics (ROC) curve in the study population. Univariate and multivariate analyses were performed by using Cox-regression modelling, and survival curves were constructed by using Kaplan-Meier method. Results: 70% of the patients were male, and the mean age was 64.9±9.9 years (mean ± SD). 70.6% of female patients and 67.9% of male patients were diagnosed with stage 4 cancer. The prevalence of sarcopenia in the whole patient group was 29.6%. By multivariate analysis, SMI (p=0.009) and advanced stage (p=0.003) were found as poor prognostic factors for overall survival (OS). The neutrophil to lymphocyte ratio (NLR) was statistically significantly higher in sarcopenic patients than in nonsarcopenic patients (p=0.031). Conclusion: Patients having sarcopenia at the time of diagnosis may demonstrate poorer overall survival of pancreatic cancer, and SMI may be considered as a potential prognostic factor.

Background: Arterial stiffness is an important biomarker for cardiovascular disease. Shear wave elastography (SWE) provides quantitative estimates of tissue stiffness. Objective: This study aimed to provide reference values for arterial wall, assessing the suitability of SWE to quantify elasticity of the common carotid artery (CCA) and evaluating inter-and intra-observer reproducibility. Methods: A Supersonic Aixplorer ultrasound system with L15-4 probe was used to scan longitudinal sections of the CCA. Young’s modulus (YM) was measured within 2-mm regions of interest. Reproducibility was assessed within a subgroup of 16 participants by two operators (one novice and one experienced) during two sessions >one week apart. Results: This study involves seventy-three participants with a mean age of 40±10 years and a body mass index of 26 ±6 kg/m2. YM estimates were 59 kPa ±19 in men and 56 kPa ±12 in women. The average YM of the CCA walls was 58 kPa ±15 (57 ±15 kPa for the anterior wall and 58 ±20 kPa for the posterior wall, p=0.75). There was no significant difference in the mean of YM estimates of the CCA between the observers (observer: one 51 ±14 kPa and observer two: 55 ±17 kPa[p=0.46]). Interand intra-observer reproducibility was fair to good (Intra-class correlations, ranging from 0.46 to 0.71). Inter-frame variability was 28%. Conclusion: In healthy individuals, SWE provided an estimate of YM of the CCA (58 kPa) with fair to good reproducibility. This study demonstrated the potential of using SWE for assessing biomechanical properties of blood vessels.

Objective: The objective of this study is to analyze the clinical and imaging features of desmoplastic fibroma of bone (DFB) for correct diagnosis. Materials and Methods: Twenty patients with DFB confirmed by pathology were enrolled, and the imaging presentations were analyzed. Among 20 patients, plain X-ray was performed in all patients, computed tomography (CT) was performed in 12, and magnetic resonance imaging (MRI) was conducted on eight. The clinical and imaging presentations were analyzed and classified to assist in correct diagnosis. Results: Twenty patients with DFB were retrieved, including eleven males and nine females with an age range of 2-52 years (median 27). The DFB involved the femur in six patients, ilium in five, tibia in four, humerus in two, lumbar vertebra in one, radius in one, and calcaneus in the remaining one. DFB was common in the metaphysis of long bones and could involve the diaphysis and epiphysis. The imaging presentations were divided into four types: the cystic expansile destruction in ten patients, osteolytic destruction in five, mixed destruction in four, and paraosseous destruction in one. CT value was 30 -60 Hu in the lesion area (6 cases CT value>45Hu). In eight patients with MRI scanning, the lesion in five patients presented with unevenly equal or low signal on T1WI and unevenly equal or high signal on T2WI, with irregular stripes or patches of low signal on both T1WI and T2WI. In the rest three patients, the lesion was evenly equal or low signal on T1WI and evenly high signal on T2WI. MRI more clearly showed a mass in the adjacent soft tissue and the range of edema in the DFB lesion. Conclusion: DFB is a rare tumor with strong local aggressiveness, cystic bone destruction, formation of tumor bone trabeculae, soft tissue masses on imaging presentations, low signals on T1WI and T2WI in the lesion, but no periosteal reaction or calcification, which are helpful for diagnosis of the disease and differentiation from other ones.

Background: We aimed to differentiate Glioblastoma Multiforme (GBM) from benign lesions like Developmental Venous Anomaly (DVA) and Cavernous Malformation (CM) by Dynamic Contrast-Enhanced MR Perfusion (DCE-MRP) markers such as Ktrans, Ve, Kep, and IAUC. Methods: We retrospectively evaluated 20 patients; 10 GBM as the malignant group, 5 CM and 5 DVA as the benign group. Ktrans, Kep, Ve, and IAUC parameters were measured by DCE-MRP, within the lesion, at perilesional nonenhancing white matter (PLWM) and contralateral normal appearing white matter (CLWM). Results: All benign and malignant lesions exhibited significantly increased Ktrans, Ve, and IAUC values compared to PLWM and CLWM (p < 0.001, p=0.006 and p<0.001). Subtracted Kep values between lesion and PLWM were significantly different between the benign and malignant groups, as the malignant group exhibited higher subtracted Kep values (p 0.035). For the malignant group; Ktrans and IAUC values at the lesion were positively correlated (r 0.911), while Kep and Ve at CLWM were negatively and strongly correlated (r 0.798). For the benign group; Ktrans with Ve and Ktrans with IAUC at lesion (r 0.708 and r 0.816 respectively), Ktrans and IAUC at PLWM (r 0.809), Ktrans and IAUC at CLWM(r 0.798) were strongly and positively correlated. Ktrans, Ve, and IAUC values can be used to restrict the lesion in both groups. Conclusion: Ktrans strongly correlates with IAUC and they can be used instead of each other in both benign and malignant lesions. Classical DCE-MRP parameters cannot be used in the differentiation of malignant lesions from benign vascular lesions. However, subtracted Kep values can be used to differentiate GBM from benign vascular lesions.

Background: The rate of autoimmune thyroiditis in children with celiac disease (CD) is high relative to the normal population. Since the majority of these patients are also euthyroid, thyroid imaging methods are gaining significance in diagnosis and follow-up. This study examines the effectiveness of thyroid ultrasonography (US) and thyroid shear wave elastography (SWE) in diagnosing thyroid disease in children with CD. Materials and Methods: This cross-sectional controlled study analyzed thyroid US, SWE, serum thyroid function tests, and thyroid autoimmune antibodies of 106 CD patients and 103 control patients without CD. An Aplio 500 ultrasound device with a linear array transducer and elastography software was used for thyroid US and SWE measurement of all patients. Results: Right lobe thyroid volume, left lobe thyroid volume, total thyroid volume, thyroid mean elasticity (m/s), right lobe elasticity (kPa), left lobe elasticity (kPa), and mean thyroid elasticity (kPa) levels of the CD group were higher than those of the control group (p < 0.001). The relationships between thyroid US and thyroid mean elasticity (m/s), thyroid mean elasticity (kPa), anti-thyroid peroxidase antibody, and thyroid-stimulating hormone were positive and moderate, respectively (r = 0.612, 0.612, 0.636, and 0.565, respectively; p < 0.001). Conclusion: In this study, SWE findings were compatible with laboratory findings, as they constituted a sensitive and useful method in the diagnosis and follow-up of autoimmune thyroid disease in children with CD.

Background: Cross-sectional imaging findings of portal vein calcification were found to be an indicator of portal vein thrombosis. Calcification of the portal vein and its tributaries in portal hypertension is an uncommon finding and the mechanical stress due to long-standing portal hypertension on the vessel wall is considered leading to sclerosis and calcification in the intima and media of the vessel wall. Intra-splenic vascular calcification is a rare occurrence and has been seen in patients with portal hypertension. Case Presentation: A 60-year-old male was referred for an ultrasound scan of the abdomen, as he was found to have mild elevation of liver enzymes during a routine medical investigation. His ultrasound scan showed features of cirrhosis and portal hypertension. Furthermore, there were intra-splenic calcifications with branching pattern. Subsequent CT confirmed intra-splenic vascular calcification and calcifications in the wall of the thrombosed portal vein and its tributaries. Conclusion: Pre-operative identification of portal venous calcification is important, as this might adversely affect surgical interventions for cirrhosis and portal hypertension. Furthermore, to our best knowledge, there have not been any cases reported with concurrent calcification of the portal venous system and intra-splenic vascular calcification in association with portal hypertension in literature.

Background: Foreign bodies in the upper aerodigestive tract represent an uncommon cause of visits to emergency departments. In the majority of cases, foreign bodies do not go beyond the pharynx. They cause dyspnoea or pneumonia if they reach the tracheobronchial tree. If ingested, they will pass spontaneously through the gastrointestinal canal in the majority of cases. Nevertheless, especially in the case of sharp-pointed or large objects, the foreign bodies can stop in the oesophagus. In case of dysphagia, stinging sensation and/or odynophagia occurring after eating a meal, a foreign body in the upper aerodigestive tract should be suspected. If not clinically visible, imaging is required. Case Presentation: A 72-year-old woman presented to the Emergency Department with pharyngodynia, odynophagia, stinging, dysphagia, and sialorrhea for 12 hours. Her symptoms started after eating a meal involving meat. The patient underwent a standard two-projection radiogram of the neck. The antero-posterior projection radiogram was unremarkable. The lateral projection radiogram showed 16 millimetres in maximum length radiopaque foreign body within the cervical oesophagus. The patient underwent transoral flexible oesophagoscopy under general anaesthesia, which resulted in successful removal of the foreign body (bony fragment). Her symptoms improved rapidly after the procedure, and the patient was discharged after 48 hours in good health. Conclusion: A foreign body in the cervical oesophagus may lead to visceral perforation. Once suspected, every effort should be made to identify and remove the foreign body to avoid potentially catastrophic consequences. In some cases, imaging could be necessary to detect the foreign body.

Background: Sinonasal cavernous hemangioma is rare. To date, fewer than 20 cases have been reported in the literature; however, they may be a source of recurrent epistaxis and masquerade of a hemorrhagic mass on CT and MRI. Case Report: A 68-year-old woman was presented with recurrent epistaxis and progressive right malar fullness. On rhinoscopy, a bulge lesion was observed with multifocal hemorrhagic and friable surfaces in the right nasal cavity. CT and MRI demonstrated a well-defined mass in the right maxillary sinus with inhomogenous T2 hyperintensity, hypointense septa, peripheral rim, and multiple papillary enhancement, suggesting a recurrent hemorrhagic mass. The mass was excised endoscopically, and the histologic diagnosis was cavernous hemangioma. Conclusion: Imaging studies, such as CT and MRI, are essential in making an accurate diagnosis of cavernous hemangioma of the maxillary sinus. Endoscopic excision of the lesion can be curative.

Introduction: Uterine tumors resembling ovarian sex cord tumors (UTROSCTs) are rare neoplasms with unknown etiology. This type of tumor has low malignant potential and mostly manifests as a benign clinical course. Materials and Methods: This article analyzes the case data, clinical manifestations, and histopathological characteristics of two cases of UTROSCT, and reviews the relevant literature. The diagnosis of UTROSCT is mainly based on histopathological examination. The histological characteristics of granulosa and Sertoli cell tumours are similar to the ovary under the microscope. These cases' clinical and radiological (MRI) findings have also been discussed. Results: The sex cord components are mixed in different proportions. The immunohistochemistry is diverse and can express sex cord markers together with both epithelial and smooth muscle markers. Both two cases revealed the signs of intratumoral cystic degeneration, intratumoral hemorrhage, and necrosis under MRI. These MRI features were helpful to prompt UTROSCT, which is histologically similar to granular cell tumors and is conducive to the differential diagnosis. Conclusion: The current recommended treatment is total hysterectomy, but its biological behavior is not yet clear, and long-term follow-up is needed.