Volumetric apparent diffusion coefficient (ADC) histogram analysis of the brain in paediatric patients with hypoxic ischaemic encephalopathy.

Purpose: To evaluate the whole brain, hippocampus, thalamus, and lentiform nucleus by volumetric apparent diffusion coefficient (ADC) histogram analysis in paediatric patients with hypoxic-ischaemic encephalopathy (HIE). Material and methods: This retrospective study included 25 patients with HIE and 50 patients as the control group. Diffusion-weighted imaging was obtained at b-values of 1000 mm2/s. The histogram parameters of ADC values, including the mean, minimum, maximum, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, as well as skewness, kurtosis, and variance were determined. The interclass correlation coefficient (ICC) was used to assess the inter-observer agreement. Results: ADCmin, ADCmean, and ADCmax, as well as the 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values for the HIE group were all lower than those of the control group (p < 0.001) in the volumetric histogram analysis of the hippocampus, thalamus, and lentiform nucleus. In the whole-brain histogram analysis, ADC min, and the 50th and 75th percentiles of ADC values did not differ significantly, while other parameters were lower in the HIE group. The ROC curve revealed that the ADC histogram parameters of the hippocampus provided the most accurate results for the diagnosis of HIE. The area under the curve (AUC) of the 95th percentile of ADC values was the highest (AUC = 0.915; cut-off 1.262 × 10-3 mm2/s; sensitivity 88% and specificity 84%). Conclusions: Volumetric ADC histogram analysis of the whole brain, hippocampus, thalamus, and lentiform nucleus with b-values of 1000 mm2/s can serve as an imaging marker for determining HIE.

Frequency of sternal variations in living individuals.

PURPOSE: To evaluate the variations of the sternum and provide the prevalence of sternal foramen and its anatomical relationships. METHODS: In this retrospective study, 544 subjects ranging in age from 18 to 95 years were evaluated. Sternal variations, prevalence of sternal foramen and its anatomical relationships to mediastinal structures were examined with the axial, sagittal and coronal reformat images of the patients who underwent thoracic computerized tomography. RESULTS: In 500 subjects, following sternal variations were found: sternal sclerotic band in 120 (24%), sternal cleft in 3 (0.6%), sternal foramen in 26 (5.2%), focal cortical notch and defect in 44 (8.8%) patients. The manubriosternal fusion was partial in 65 (13%) patients and complete in 112 (22.4%) patients. The sternoxiphoid fusion was partial in 201 (40.2%) and complete in 153 (30.6%) patients. There was no xiphoid process in 9 patients (1.8%; 29-51 years; mean age 38 years). Xiphoidal ending types were as follows: single-ended 361 (72.2%), double-ended 125 (25%), and triple-ended xiphoid 5 (1%) patients. The sternal foramen was adjacent to the lung in 13 (2.6%), to the pericardium of heart in 3 (0.6%), and to mediastinal fat in 10 (2%) patients. CONCLUSION: The sternum is a very critical anatomic structure of the anterior chest wall with several variations that can be confused with pathologic conditions. Radiologists' familiarity with these variations is important for better radiologic evaluation in making differential diagnosis.

Diagnostic Value of Pericholedochal Hypointense Ring Sign in MRI T2W Images in Cases of Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: To determine the value of hypointense pericholedocal ring sign in magnetic resonance imaging (MRI) T2W sequence images in the diagnosis of pancreatic ductal adenocarcinoma (PDA). STUDY DESIGN: Retrospective observational study. Place and Duration of the Study: Department of Radiology, Bakirkoy Dr Sadi Konuk Training and Research Hospital, Istanbul, Turkiye, from January 2016 and March 2022. METHODOLOGY: Retrospective analysis of MRI scans was performed on 70 patients with postoperative histopathological confirmation of a diagnosis of periampullary cancer. The patients' demographic information, the results of their histopathological examinations, and the findings of their MRIs were recorded. The results of the MRI were statistically analysed and compared between the PDA and the non-PDA groups. RESULTS: The study included 43 (61.4%) male and 27 (38.5%) female patients, with a mean age of 62.2 ± 8.4 years. The means of Wirsung diameter and tumour diameter were significantly higher in PDA group (p = 0.034, p = 0.010, respectively). A progressive contrast enhancement pattern of 95.3% was observed in PDA group, while 40.7% rapid contrast enhancement pattern was observed in the non-PDA group. Hypointense pericholedochal ring sign, observed in T2W sequences, was detected in 74.2% (n = 32) of the PDA group and 11.1% (n = 3) of the non-PDA group, and the findings were statistically significant (p <0.001). CONCLUSION: Hypointense pericholedochal ring sign in axial T2W sequences in periampullary tumours is a complementary MRI finding in the distinction between the PDA and the non-PDA groups. KEY WORDS: Magnetic resonance imaging, Pancreatic ductal adenocarcinoma, Periampullary tumours, Pericholedochal ring sign.

Intrahepatic Splenosis: A Rare Case.

BACKGROUND: Splenosis refers to the autotransplantation of splenic tissue in a heterotopic location throughout different anatomic compartments, such as the peritoneal and pelvic cavities and even the thoracic cavity. Intrahepatic splenosis is very rare and usually mistaken for a neoplasm. The lack of typical radiological features makes it difficult to distinguish splenosis from liver tumors. CASE REPORT: A 33-year-old female patient presented with post-traumatic splenectomy and had a history of recurrent surgery afterward. There were no significant findings in the physical examination or lab values. Imaging findings were non-specific, with nodular lesions in the liver and scattered in the abdomen. Due to the patient's history, splenosis was considered in the differential diagnosis, and finally, scintigraphy was performed, which confirmed the diagnosis, so unnecessary surgery was avoided. DISCUSSION: Splenosis is the implantation of splenic tissue after an elective or traumatic splenic rupture. US imaging indicates a hypoechoic to isoechoic mass. Low signal intensity on T1 and iso-to-high signal intensity on T2-weighted images are common MRI findings of splenosis. The arterial phase of spleen implantation is varied. Delayed phase signal intensity is usually less than the liver parenchyma. The spleen has the lowest ADC value and the most restricted diffusion of all the intra-abdominal organs. CONCLUSION: In conclusion, splenosis should be considered in the differential diagnosis of patients with a history of spleen surgery or abdominal trauma. It should correlate with the clinical history.

Zinner Syndrome: Radiologic Diagnosis in a Rare Case.

BACKGROUND: Zinner's syndrome is a rare congenital malformation of the seminal vesicle and ipsilateral upper urinary tract caused by mesonephric duct developmental anomaly during early embryogenesis. This study aimed to demonstrate the significance of magnetic resonance imaging (MRI) in distinguishing pelvic cysts in males, given that MRI is the gold standard exam for confirming the diagnosis and managing therapy. CASE REPORT: A 21-year-old male patient with a solitary kidney who had been diagnosed since birth presented with abdominal pain. Transabdominal and transrectal ultrasonography (US), computed tomography (CT), and MRI were performed. The contrast-enhanced MRI of the pelvis showed a tubular fluid-filled, macrolobulated lesion measuring 6 x 6 x 4 cm, mildly high signal intensity in the T2-weighted images, and slightly high signal intensity in the T1-weighted images, without contrast enhancement. The left kidney was hypoplasic. Imaging findings led to the diagnosis of Zinner's syndrome, and conservative treatment was planned. DISCUSSION: Zinner's syndrome is characterized by a triad consisting of unilateral renal agenesis or hypoplasia, ipsilateral seminal vesicle cyst, and ipsilateral ejaculatory duct obstruction. MRI is the modality of choice for an impeccable depiction of the anatomy of the male genital tract, for demonstrating the seminal vesicles and evaluating anomalies of the mesonephric duct. It is also useful in distinguishing seminal vesicle cysts from other cystic pelvic masses. CONCLUSION: Zinner's syndrome should be considered when diagnosing cystic pelvic masses in males with renal agenesis or hypoplasia. Because of its high soft tissue contrast resolution, MRI is the gold standard modality for confirming the diagnosis and assessing the cyst's origin and contents.

Differentiating renal cell carcinoma and oncocytoma with volumetric MRI histogram analysis.

OBJECTIVE: In this study, the utility of histogram parameters derived from diffusion-weighted imaging for differentiate renal cell carcinoma (RCC) from oncocytoma was investigated. METHODS: This research tracked 126 individuals who were diagnosed with RCC and oncocytoma through histopathological analysis, using magnetic resonance imaging (MRI) assessments from 2015 to 2023. We observed various attributes of these patients, including demographic details, surgical records, pre-surgery MRI results, MRI apparent diffusion coefficient (ADC) histogram analysis, and post-surgery histopathological outcomes. Calculations of ADC measurements such as mean, minimum, and maximum in conjunction with the 5th, 10th, 25th, 50th, 75th, 90th, and 95th quantile points were made. In addition, we also noted the skewness, kurtosis, and variance of these data points. RESULTS: The focus group for this investigation consisted of 75 male and 51 female patients. Out of these, 82 were diagnosed with RCC and 44 with oncocytoma. All ADC parameters including ADCmin, ADCmedian, ADCmean, and ADCmax, including the 5th, 10th, 25th, 50th, 75th, 90th, and 95th quantile divisions among the oncocytoma cohort were observed to be higher than the corresponding ones in the RCC group. A statistically meaningful difference was discovered between the minimum ADC value along with the 5th ranking of ADC measurements (p<0.001), in addition to mean of ADC (p=0.050), and the 10th (p=0.002) and 25th (p=0.015) quantiles of ADC data. When considering the region below the curve (AUC) in ROC analysis, the value of ADCmin was recorded as 0.739, with a sensitivity of 75.0%, and specificity of 68.2%. CONCLUSION: To distinguish oncocytoma from RCC, it may be useful to conduct a whole-tumor histogram and textural analysis of ADC values.

The Effectiveness of Volumetric MRI Histogram Analysis in Renal Cell Carcinoma.

RATIONALE AND OBJECTIVES: This study investigated the utility of histogram parameters derived from diffusion-weighted imaging (DWI) for evaluating renal cell carcinoma (RCC) grading prior to surgery. MATERIALS AND METHODS: This retrospective study included 88 patients who were histopathologically diagnosed with RCC and underwent magnetic resonance imaging (MRI) examinations. The patients were divided into two groups as well-differentiated (Group 1) and poorly differentiated (Group 2). Demographic data, preoperative MRI findings, MRI apparent diffusion coefficient (ADC) histogram analyzes, operation types, postoperative histopathological data and cancer stages of the patients were recorded. The histogram parameters of ADC values, comprising the mean, minimum, maximum, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, as well as skewness, kurtosis, and variance, were calculated. RESULTS: The study included 59 males and 29 women with an average age of 56.21 ± 1.33 years. There were 52 patients in Group 1 and 36 patients in Group 2. The ADCmin, ADCmean, ADCmax, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles of ADC values of the poorly differentiated group were all lower than those of the well-differentiated group. ADCmin and the 5th percentile of ADC values, as well as ADCmean and the 10th, 25th, 50th, and 75th percentiles of ADC values, showed a statistically significant difference (p < 0.05). The AUC, sensitivity, and specificity of the ADCmin value were 0.703, 56.3%, and 75.7%, respectively. CONCLUSION: The present study indicated that histogram parameters generated from DWI were capable of differentiating between high-grade and low-grade RCC.

Analysis of Pancreatobiliary and Intestinal Type Periampullary Carcinomas Using Volumetric Apparent Diffusion Coefficient Histograms.

RATIONALE AND OBJECTIVES: Magnetic resonance imaging plays an important role in the evaluation of patients with known or suspected periampullary masses. The utilization of volumetric apparent diffusion coefficient (ADC) histogram evaluation for the entire lesion eradicates the potential for subjectivity in the region of interest placement, thus guaranteeing the accuracy of computation and repeatability. PURPOSE: To investigate the value of volumetric ADC histogram analysis in the differentiation of intestinal-type (IPAC) and pancreatobiliary-type periampullary adenocarcinomas (PPAC). MATERIALS AND METHODS: This retrospective study included 69 patients with histopathologically confirmed periampullary adenocarcinoma (54 PPAC and 15 IPAC). Diffusion-weighted imaging was obtained at b values of 1000 mm²/s. The histogram parameters of ADC values, comprising the mean, minimum, maximum, 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles, as well as skewness, kurtosis, and variance, were calculated independently by two radiologists. Using the interclass correlation coefficient, the interobserver agreement was evaluated. RESULTS: The ADC parameters for the PPAC group were all lower than those of the IPAC group. The PPAC group had higher variance, skewness, and kurtosis than the IPAC group. However, the difference between the kurtosis (P = .003), the 5th (P = .032), 10th (P = .043), and 25th (P = .037) percentiles of ADC values was statistically significant. The area under the curve (AUC) of the kurtosis was the highest (AUC=0.752; cut-off value=-0.235; sensitivity=61.1%; specificity=80.0%). CONCLUSION: Volumetric ADC histogram analysis with b values of 1000 mm²/s can discriminate subtypes noninvasively before surgery.

Evaluation of Imaging Findings of Pancreatobiliary and Intestinal Type Periampullary Carcinomas with 3.0T MRI.

RATIONALE AND OBJECTIVES: The aim of this study was to differentiate pancreatobiliary and intestinal type periampullary carcinomas using dynamic contrast MRI and MRCP (Magnetic Resonance Cholangiopancreatography) with diffusion-weighted imaging (DWI) MATERIALS AND METHODS: MRI and MRCP images of 70 patients with pathologically proven periampullary adenocarcinoma were included. MRCP image features, extra-ampullary features, enhancement patterns, and apparent diffusion coefficient (ADC) values derived from b-values of 1000 s/mm² were evaluated by two radiologists independently. The interclass correlation coefficient (ICC) or Cohen's kappa statistic was used to evaluate the interobserver agreement. RESULTS: 51 patients were diagnosed with pancreatobiliary type carcinomas, and 19 with intestinal type. In the pancreatobiliary subtype, the distal wall of the common bile duct was usually irregular (p = 0.047). Although the progressive enhancement pattern was evident in the pancreatobiliary type, an oval filling defect in the distal common bile duct was found to be more common in the intestinal type (p<0.001). The pancreatic duct cut-off sign (p<0.001), gastroduodenal artery involvement (p <0,001), and lymphadenopathy (p<0.05) were mostly observed in pancreatobiliary carcinomas. The ADCmin, ADCmean, and ADCmax values of the pancreatobiliary type carcinomas were all lower compared to the intestinal type carcinomas (p <0.05). CONCLUSION: The oval filling defect seen in MRI and MRCP examinations suggests intestinal type, whereas the progressive contrasting pattern of the masses with irregular narrowing in the distal margin of the common bile duct, the pancreatic duct cut-off sign, gastroduodenal artery involvement, lymphadenopathy, and low ADC values indicate pancreatobiliary type carcinomas.

The value of shear wave elastography in the quantification of corpus cavernosum penis rigidity and its alteration with age.

OBJECTIVE: The goal of this study was to measure corpus cavernosum (CC) penis rigidity with shear wave elastography (SWE) in healthy volunteers and to evaluate the change of rigidity with age. METHODS: SWE was performed in 60 healthy volunteers (age range 20-71, mean 47±12,83 years). Volunteers were divided into 2 groups by age (Group 1 age <50, group 2 age ≥50). We assessed SWE in 3 parts of penis (proximal, middle and glans penis) on both sides of CC. All values of SWE (in kilo Pascal) were noted along with volunteers' ages. The measurements were done both with transverse (T) and longitudinal (L) sections. We compared all SW values of penis parts and their alterations with age. RESULTS: The shear wave elastography values of CC penis increased with increasing age (p<0,01). There was no significant difference between both sides of CC penis (p<0,05). We calculated no significant difference between T and L sections of all parts of penis (p<0,05). CONCLUSIONS: SWE can provide noninvasive quantitative data of CC penis rigidity and its alteration with age. These data may create a new approach in the evaluation process and treatment options for penile pathologies.