Efficacy of diffusion weighted imaging in sacroiliac joint MRI in children.

OBJECTIVE: Because of the immature bone marrow signal in children, assessment of the sacroiliac joint is more difficult than in adults. Aim of this study is to evaluate the efficacy of diffusion-weighted imaging (DWI) in sacroiliac joint magnetic resonance imaging (MRI). METHODS: Sacroiliac joint MRI, including DWI sequences, were evaluated by two pediatric radiologists in 54 patients with sacroiliitis and 85 completely normal controls. In MRI evaluation, subchondral bone marrow edema and contrast enhancement in the sacroiliac joints were considered as active sacroiliitis. Apparent diffusion coefficient (ADC) measurements were made in six areas from each sacroiliac joint. A total of 1668 fields were evaluated retrospectively without their diagnosis being known. RESULTS: When the postcontrast T1W series were referenced, the sensitivity, specificity, positive predictive value, and negative predictive value of short time inversion recovery (STIR) images in the diagnosis of sacroiliitis were 88%, 92%, 83% and 94% respectively, compared to contrast-enhanced images. False positive results in STIR images were observed secondary to the flaring signal in the immature bone marrow. ADC measurements obtained from diffusion-weighted images were recorded in all patients and healthy groups. The ADC values were 1.35x10-3 mm2/s (SD: 0.21) in the areas of sacroiliitis, 0.44x10-3 mm2/s (SD: 0.71) in the normal bone marrow and 0.72x10-3 mm2/s (SD: 0.76) in the immature bone marrow areas. CONCLUSION: Although STIR studies are an effective sequence in the diagnosis of sacroiliitis, they cause false positive results in immature bone marrow in children in inexperienced hands. DWI is an objective method that prevents errors in the assessment of sacroiliitis by means of ADC measurements in the immature skeleton. In addition, it is a short and effective MRI series that makes important contributions to the diagnosis without the need for contrast-enhanced examinations in children.

PROPELLER diffusion weighted imaging for diagnosis of cholesteatoma in comparison with surgical and histopathological results: emphasis on false positivity and false negativity.

PURPOSE: To investigate the role of non-echo planar diffusion weighted imaging (DWI) using "periodically rotated overlapping parallel lines with enhanced reconstruction" (PROPELLER) sequence for the diagnosis of cholesteatoma compared to surgical and histopathological results in an attempt to determine the factors causing false negative and false positive diagnoses. METHODS: Patients who had PROPELLER DWI before ear surgery were retrospectively reviewed. The presence of a lesion with diffusion restriction on PROPELLER DWI was accepted as positive for cholesteatoma, and the results were compared to the intraoperative and histopathological findings. RESULTS: A total of 112 ears in 109 patients were reviewed. On PROPELLER DWI, a lesion with diffusion restriction was found in 101 (90.2%) ears, while in 11 (9.8%) of the patients, no diffusion restriction was found. Surgery and histopathological analysis revealed a cholesteatoma in 100 (89.3%) ears, while in 12 (10.7%) ears, no cholesteatoma was found surgically. There were 96 (85.7%) true positives, 7 (6.2%) true negatives, 5 (4.5%) false positives and 4 (3.6%) false negatives. The accuracy, sensitivity, specificity, positive predictive and negative predictive values of non-echo planar DWI were calculated to be 91.96%, 96%, 58.33%, 95.05%, and 63.64%, respectively. CONCLUSION: Non-echo planar DWI using PROPELLER sequence has high accuracy, sensitivity and positive predictive value and can be used for the detection of cholesteatoma. The external auditory canal, postoperative ears and small lesions should be evaluated with caution to avoid false results.

Chest computed tomography findings of 1271 patients with COVID-19 pneumonia and classifications with different age groups: a descriptive study from Istanbul, Turkey.

OBJECTIVE: The objectives of this study were to describe lung computed tomography findings of patients with COVID-19 diagnosed by real-time reverse transcription polymerase chain reaction test, investigate whether the findings differ regarding age and gender, and evaluate the diagnostic performance of chest computed tomography based on the duration of symptoms at the time of presentation to the hospital. METHODS: From March 11 to May 11, 2020, 1271 consecutive patients (733 males and 538 females) were included in this retrospective, cross-sectional study. Based on age, patients were divided into five separate subgroups. Then based on the duration of symptoms, patients were divided into five separate phases. The presence of lung lesion(s) and their characteristics, distribution patterns, and the presence of concomitant pleural thickening/effusion and other findings (malignancy, metastasis, chronic obstructive pulmonary disease, interstitial lung disease, bronchiectasis, bronchiectasis, cardiomegaly, pericardial effusion) were evaluated by five radiologists independently. RESULTS: The "normal lung computed tomography finding" was the most common chest CT finding (37%), followed by ground-glass opacity (31%). Regardless of the shape of the lesion, the distribution features were significant (peripheral, subpleural, and lower lobe distribution) (p<0.05). The presence of pleural thickening posteriorly and adjacent to the lesion was statistically different in groups 1-3 (p<0.05). Other concomitant pathologies, except pulmonary congestion, did not suppress the typical findings of COVID-19. CONCLUSION: Chest computed tomography findings were mostly normal in the early phase (P1). Therefore, it may be appropriate to perform the first computed tomography screening of COVID-19 after 6 days to decrease the radiation exposure.

Chest computed tomography findings of 1271 patients with COVID-19 pneumonia and classifications with different age groups: a descriptive study from Istanbul, Turkey

SUMMARY OBJECTIVE: The objectives of this study were to describe lung computed tomography findings of patients with COVID-19 diagnosed by real-time reverse transcription polymerase chain reaction test, investigate whether the findings differ regarding age and gender, and evaluate the diagnostic performance of chest computed tomography based on the duration of symptoms at the time of presentation to the hospital. METHODS: From March 11 to May 11, 2020, 1271 consecutive patients (733 males and 538 females) were included in this retrospective, cross-sectional study. Based on age, patients were divided into five separate subgroups. Then based on the duration of symptoms, patients were divided into five separate phases. The presence of lung lesion(s) and their characteristics, distribution patterns, and the presence of concomitant pleural thickening/effusion and other findings (malignancy, metastasis, chronic obstructive pulmonary disease, interstitial lung disease, bronchiectasis, bronchiectasis, cardiomegaly, pericardial effusion) were evaluated by five radiologists independently. RESULTS: The "normal lung computed tomography finding" was the most common chest CT finding (37%), followed by ground-glass opacity (31%). Regardless of the shape of the lesion, the distribution features were significant (peripheral, subpleural, and lower lobe distribution) (p<0.05). The presence of pleural thickening posteriorly and adjacent to the lesion was statistically different in groups 1-3 (p<0.05). Other concomitant pathologies, except pulmonary congestion, did not suppress the typical findings of COVID-19. CONCLUSION: Chest computed tomography findings were mostly normal in the early phase (P1). Therefore, it may be appropriate to perform the first computed tomography screening of COVID-19 after 6 days to decrease the radiation exposure.

Evaluation of radiological findings in pediatric patients with COVID-19 in Turkey.

OBJECTIVE: The objective of the study was to describe the findings of pediatric patients diagnosed with COVID-19 in computed tomography (CT) and chest X-ray (CXR) images. Therefore, the aim of this study is to show protecting the children from radiation as much as possible while guiding the diagnosis. METHODS: Between March and June 2020, 148 pediatric patients examined who underwent CT due to suspicion of COVID-19. Fifty patients of 148 with normal thorax CT and negative reverse transcription polymerase chain reaction (RT-PCR) were excluded from the study. Of the remaining 98 patients were evaluated retrospectively by two pediatric radiologists with 15 years of experience. RESULTS: The demographic, clinical, and laboratory data were evaluated for 52 RT-PCR-positive patients. CT finding of 23 RT-PCR positive and 12 negative patients was classified. According to our study, unilateral (61-67%), multifocal (50-52%), and peripheral (83-91%) involvement were higher in all groups. Lower lobe involvement was frequently detected (58-65%). The most frequently detected parenchymal lesion was ground-glass opacity followed by consolidated areas accompanying ground-grass opacities. Halo sign and vascular enlargement signs were the common signs of lung lesions (35%). In addition, some rare findings not previously described in this disease in children were mentioned in this study. The clinical course of all our patients was mild and control radiological imaging checked by CXR. CONCLUSION: Most pediatric patients have a mild course. Hence, a balance between the risk of radiation and necessity for chest CT is very important. Low-dose CT scan is more suitable for pediatric patients but still it should be used cautiously.

Does Gadoterate Meglumine Cause Gadolinium Retention in the Brain of Children? A Case-Control Study.

BACKGROUND: Accumulation of macrocyclic gadolinium agents in children's brains remain to be determined. PURPOSE: To demonstrate whether there is an intracranial macrocyclic gadolinium deposition after multiple contrast-enhanced MRI with gadoterate meglumine in a pediatric population. STUDY TYPE: Retrospective case-control. POPULATION: In all, 45 children (age range: 5-17 years; mean, 13.7 ± 3.4 years) for the study group and 45 healthy children (age range: 5-17 years; mean, 13.7 ± 3.4 years) for the control group. FIELD STRENGTH/SEQUENCE: T1 - and T2 -weighted axial images on a 1.5T scanner. ASSESSMENT: Children with at least three enhanced brain MRIs and an age- and sex-matched control group with an unenhanced brain MRIs were compared in terms of T1 signal intensity (SI). All patients in the study group received gadoterate meglumine intravenously (0.1 mmol/kg). SI measurements were made by drawing six regions of interest (ROIs): dentate nuclei (DN), pons, globus pallidi (GP), frontal white matter (FWM), thalamus (T), clivus, and cerebrospinal fluid (CSF) for both groups on unenhanced T1 -weighted images. STATISTICAL TESTS: Student's t-test was used for comparison of SI. The Pearson correlation was calculated for the correlation between the SI and the number of gadolinium administrations. RESULTS: A significant difference was detected between two groups for DN/CSF, pons/CSF, GP/CSF, thalamus/CSF, and FWM/CSF (P < 0.001, P < 0.001, P = 0.002, P = 0.002, P = 0.024, respectively). There was no significant difference between the two groups for clivus/CSF (P = 0.15). A good correlation between the number of gadoterate meglumine administrations and the SI for DN/CSF, pons/CSF, GP/CSF, and T/CSF (r = 0.80, r = 0.73, r = 0.91, and r = 0.90, respectively) was found. DATA CONCLUSION: A significant T1 SI increase reflecting gadolinium retention in the brain was detected for children with at least three gadoterate meglumine administrations in this series. The number of administrations correlated well with the increased SI. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;51:1471-1477.

Role of Interface Sign and Diffusion-Weighted Magnetic Resonance Imaging in Differential Diagnosis of Exophytic Renal Masses.

PURPOSE: We aimed to investigate the role of interfaces of exophytic solid and cystic renal masses on magnetic resonance imaging (MRI) and the added value of diffusion-weighted imaging in differentiating benign from malignant lesions. METHODS: The Institutional Review Board approved this retrospective study, and informed consent was waived. A total of 265 patients (109 [41%] women and 156 [59%] men) with a mean age of 57 ± 12 (standard deviation) years were enrolled in this study. Preoperative MRI (n = 238) examinations of patients with solid or cystic renal masses and MRI (n = 27) examinations of patients with Bosniak IIF cysts without progression were reviewed. Solid/cystic pattern, interface types and apparent diffusion coefficient (ADC) values were recorded by 2 radiologists. The diagnostic performance of combining normalized ADC values with interface sign were evaluated. RESULTS: Among 265 renal lesions (109 cystic and 156 solid), all malignant lesions (n = 192) had a round interface. No malignant lesions showed an angular interface. For prediction of benignity in cystic lesions, sensitivity (82.86% vs 56.16%), negative predictive value (92.50% vs 85.71%), and accuracy (94.50% vs 87.92%) ratios of angular interface were higher compared to all (solid plus cystic) lesions. The best normalized ADC cutoff values for predicting malignancy in lesions with round interface were as follows: for all (solid plus cystic), ≤ 0.75 (AUROC = 0.804); solid, ≤ 0.6 (AUROC = 0.819); and cystic, ≤ 0.8 (AUROC = 0.936). CONCLUSIONS: Angular interface can be a predictor of benignity for especially cystic renal masses. The evaluation of interface type with normalized ADC value can be an important clue in differential diagnosis especially in patients avoiding contrast.

Misleading findings of liver-specific MR contrast agent for radiological diagnosis of cysto-biliary communication in hydatid cysts.

OBJECTIVE: To investigate the effectiveness of gadoxetic acid-enhanced magnetic resonance cholangiopancreatography (CE-MRCP) and T2-weighted half-Fourier acquisition single-shot turbo spin-echo (T2W HASTE) sequences for diagnosis of cysto-biliary communication in hydatid cysts compared to surgical results. METHODS: Preoperative abdominal magnetic resonance imaging examinations of patients who underwent surgery for hepatic hydatid cysts were reviewed by two radiologists retrospectively. A total of 45 patients with hydatid cysts were included. Of 45, 27 also had CE-MRCPs. T2W HASTE sequences and CE-MRCPs were investigated separately for cysto-biliary communication. The relationship between radiological and surgical results was analyzed. The interobserver agreement was evaluated. RESULTS: Of 45 hydatid cysts, there were surgically proven 21 cysts without biliary communications and 24 cysts with biliary communications. All cysts with biliary communications were shown on T2W HASTE sequences. There was no leakage of gadoxetic acid into these cysts (n = 24). Sensitivity, specificity, negative predictive value, positive predictive value (PPV), and accuracy of diagnosis of cyst with biliary communication on T2W HASTE sequences was 100%, 63.64%, 100%, 66.67%, and 78.95%, respectively. Specificity (77.78%), PPV (87.50%), and accuracy (91.30%) were increased in ≥ 10 cm cysts. There was almost perfect interobserver agreement (K = 0.81-1.00). CONCLUSION: Leakage of gadoxetic acid inside the cyst indicates biliary communication. However, the lack of leakage does not rule out cysto-biliary communication. When biliary communication is clearly shown on T2W HASTE sequences, it should be reported as cysto-biliary communication even if there is no leakage of gadoxetic acid into the cyst on CE-MRCP.

Bone Deformities as a Complication of Giant Thoracic Aortic Aneurysm.

The contained rupture of thoracic aortic aneurysm and related bone deformities is a rare condition. The diagnosis is critical due to potential and fatal complications. Radiologic evaluation is required to show the location, extension, and complications. Herein we present the X-ray radiography, ultrasonography, computed tomography, and magnetic resonance images of a giant dissected and contained rupture of the thoracic aortic aneurysm. The aneurysm destructed the adjacent vertebrae and rib, resulting in compression of dural sac and spinal cord, and obliteration of the neural foramina. Our case demonstrates a gigantic expansion of an aneurysm (14 cm) with chronic skeletal complications.

Percutaneous cholecystostomy: A curative treatment modality forelderly and high ASA score acute cholecystitis patients.

BACKGROUND: Acute cholecystitis (AC) is a common emergency seen by general surgeons. Optimal treatment is laparoscopic cholecystectomy (LC); however, in cases where surgery cannot be performed due to high risk of morbidity and mortality, such as in elderly patients with comorbid diseases, other treatment modalities may be used. Percutaneous cholecystostomy (PC) is one alternative method to treat AC. PC can be used to provide drainage of the gall bladder and control infection. Subsequently, interval cholecystectomy can be performed when there are better conditions. Presently described is experience and results with PC in high risk, elderly patients with AC. METHODS: Medical records of all consecutive patients who underwent PC between January 2011 and January 2014 were identified. Tokyo Guidelines were used for definitive diagnosis and severity assessment of AC. Senior surgeon elected to perform PC based on higher risk-benefit ratio due to comorbidity, age, or duration of symptoms. All PC procedures were performed by the same interventional radiologist under local anesthesia with ultrasonographic guidance. RESULTS: Total of 40 PC procedures were performed during the study period. Of those, 22 (55%) were male and 18 were (45%) were female, with median age of 70.5 years (range: 52-87 years). All of the patients had American Society of Anesthesiologists classification of either 3 or 4. Success rate of PC was 100% with complication rate of 2.5% (n=1). One patient was operated on shortly after PC procedure due to bile peritonitis complication. PC drains were kept in place for 6 weeks. Total of 16 patients (40%) had surgery following removal of PC drain. In 3 (18.8%) cases, conversion from LC was required. Remaining 23 (57.5%) patients did not have subsequent operation after drain removal. No disease recurrence was observed in follow-up. CONCLUSION: When elderly patients present in emergency setting with AC and LC cannot be performed due to comorbid disease or poor general condition, PC can be performed safely. After removal of PC drain, LC may be performed with acceptable conversion rate of 18.8%.

The association of patellofemoral joint morphology with chondromalacia patella: a quantitative MRI analysis.

The relationship of patellofemoral congruency with chondromalacia patellae (CP) was retrospectively evaluated. Lateral patellar tilt angle (LPTA), sulcus angle (SA), trochlear depth (TD), and patella angle (PA) were measured at 301 knee magnetic resonance images and compared between groups with and without CP. In the CP group, LPTA and TD were significantly low (P<.01), SA was high (P<.01), while PA showed no difference (P>.05). The parameters were also compared between groups with mild and severe CP, and no significant difference was found (P>.05). Our results demonstrate that patellar tilt and trochlear dysplasia are related to the presence but not the degree of CP.

The value of ultrasound elastography in differentiation of malignancy in thyroid nodules.

We aimed to determine the value of ultrasound elastography (US-E) using carotid artery pulsation in differentiation of malignant and benign thyroid nodules. One hundred ten nodules were evaluated by US-E, and stiffness scores were compared to biopsy results. When cutoff for malignancy was determined as score 4, sensitivity, specificity, positive predictive value, and negative predictive value were 100%, 95%, 40%, and 100%, respectively. We suggest fine needle aspiration biopsy to be performed in all score 4 nodules, while biopsy may be unnecessary in score 1 nodules. Benign biopsy result in a score 4 nodule should suggest radiological-pathological disagreement, and repeat biopsy should be recommended.

Thyroid functions after contrast agent administration for coronary angiography: a prospective observational study in euthyroid patients.

OBJECTIVE: This study aims to investigate long-term effects of iodinated radiographic contrast media used for coronary angiography (CAG) on the thyroid function in euthyroid patients. METHODS: In a prospective observational cohort study, nonionic iodinated contrast material was electively used in 101 patients for coronary angiography. The patients were recruited without age restrictions and, at baseline, all had normal levels of free triiodothyronine (FT3), free thyroxine (FT4) and thyrotropin (TSH). The morphology of the thyroid was evaluated by thyroid ultrasonography (USG). Four and eight weeks after CAG, serum TSH, FT3 and FT4 levels were assessed. RESULTS: Compared to a mean baseline level of 1.49 (25%-75%, range 13-2.21), follow-up TSH levels decreased significantly to 1.45 (25%-75%, range 1.98-0.92, p=0.017) and 1.40 (25%-75%, range 1.89-0.87, p=0.003) at 4 weeks and 8 weeks, respectively (p=0.008). No significant diffe-rence was observed in TSH levels between the 4th and 8th weeks (p=0.833). CONCLUSION: Iodinated radiographic contrast agents may cause subclinical hyperthyroidism in euthyroid patients undergoing CAG.

Anomalous left pulmonary artery without sling formation.

A case of aberrant left pulmonary artery originating from the right pulmonary artery resembling pulmonary artery sling malformation, but without true sling formation, is presented. Anomalous left pulmonary artery was accompanied with long-segment proximal tracheal stenosis and other congenital malformations typically associated with PAS complex. The anomalous pulmonary artery passed anterior to the trachea; therefore, no true sling was formed. Because no airway compression by the aberrant left pulmonary artery was detected, the proximal tracheal stenosis was thought to be primary.

Pulmonary multislice computed tomography findings in acute aortic dissection.

OBJECTIVE: To document the type and incidence of pulmonary multislice computed tomography (CT) findings at presentation in patients with acute aortic dissection. MATERIALS AND METHODS: Multidetector CT scans of 36 patients with a diagnosis of acute aortic dissection or intramural hematoma were retrospectively reviewed. RESULTS: Pleural effusion, dependent stasis, mosaic attenuation, interlobular septal thickening, thickening of the peribronchovascular interstitium, vascular enlargement, compression atelectasis were common findings. Additionally air trapping, emphysema, consolidation, nodules, bronchiectasis or scarring were also noted. CONCLUSIONS: Various pulmonary imaging findings may accompany acute aortic dissection. These findings and their clinical significance should be further investigated.

Stent-graft placement for urgent treatment or prevention of bleeding.

BACKGROUND: Stent-graft treatment of the patients with ongoing bleeding may be beneficial in specific situations, especially when preservation of blood flow to the distant organs is important. PURPOSE: To present the results of stent-graft placement for urgent treatment or prevention of the bleeding. MATERIAL AND METHODS: Stent-graft placement was performed urgently for the treatment of active bleeding and/or pseudoaneurysm/aneurysm in 17 patients. Diagnoses were based on clinical findings and/or imaging studies. The etiology was previous major surgery and/or percutaneous intervention in 13, malignancy in one, pancreatitis and pseudocyst in one, multitrauma due to traffic accident in one and unknown cause in one patient. RESULTS: A total of 23 stent-grafts were placed. Angiograms obtained after placement revealed patent stent-graft with no further active extravasation or filling of pseudoaneurysm in 14 patients. Due to persistent bleeding, embolization was performed in two patients. In three patients, the stent-grafts were found to be thrombosed either immediately after placement (n = 1) or at follow-up (n = 2). Stent-grafts were patent in six of nine patients that could be followed (between 3 months and 6 years). CONCLUSION: Urgent stent-graft placement may be an alternative to endovascular embolization or surgery. It may be preferred when embolization is technically difficult or impossible and/or when preservation of blood supply to distal organs is essential such as in liver transplant grafts or extremity salvage.

Polysplenia/heterotaxy syndrome associated with aortic coarctation and multiple venous anomalies: multidetector computed tomography findings.

Polysplenia/heterotaxy syndrome is a rare condition involving multiple gastrointestinal, vascular, and cardiac malformations. We present a previously unreported association of aortic coarctation, double superior vena cava, a left-hand side inferior vena cava with hemiazygos vein continuation and a right retroaortic renal vein with polysplenia/heterotaxy syndrome. Multidetector computed tomography with multiplanar reconstruction images were useful in the detection of these abnormalities.