Iranian Journal of Radiology
Year:2019 | Volume:16 | Issue:4|Papers Count:15

Carcinoma ex pleomorphic adenoma is an uncommon tumor of salivary gland; moreover, myoepithelial carcinoma of palate is exceedingly rare. This report documents a case of carcinoma ex pleomorphic adenoma arising in the hard palate. A 51-year-old woman presented with foreign body sensation without pain. Preoperative biopsy was performed and resulted in pleomorphic adenoma of the hard palate. MR imaging fi ndings were well circumscribed, dome-shaped, lobulated mass with hyposignal intensity at peripheral fi brous capsule on T2WI. The mass showed internal cyst, hemorrhage, necrosis and heterogeneous enhancement. Because it showed both benign and malignant fi ndings, the radiologic diagnosis was likely to be a malignant tumor of palate. Postoperative pathological analysis revealed invasive myoepithelial carcinoma ex pleomorphic adenoma.

Background: Hypoxia is an important cause of recurrence and metastasis of malignant tumors. Noninvasive detection of the extent of hypoxic areas of tumors is essential for delineation of radiotherapy target areas and dose. Objectives: To investigate the feasibility of-MNLS) hypoxic imaging to monitor the tumor hypoxic state in tumor-bearing mice after radiotherapy. Materials and Methods: Tumor-bearing mice were divided into eight groups: imaged 24 hours before radiotherapy (A24 h before), imaged immediately after radiotherapy (Aimmediately), imaged 24 hours after radiotherapy (A24 h), imaged 48 hours after radiotherapy (A48 h), and the corresponding control groups. Mice in each group received hypoxia imaging at the corresponding time point to calculate the radioactivity ratio of tumor/non-tumor (T/NT). Hypoxia inducible factor-1 (HIF-1 ) was determined by immunohistochemistry to investigate the relationship between T/NT ratio and HIF-1 expression in radiotherapy and control groups. Results: T/NT ratio and the expression of HIF-1 in A24 h group were not signifi cantly diff erent from those in A24 h before and control groups, but lower than those in the Aimmediately group and higher than those in the A48 h group. T/NT ratio and the expression of HIF-1 in the A24 h before group had no signifi cant diff erence compared with those in its control group, while those in the Aimmediately group were remarkably higher than those in its control group. On the other hand, those in A48 h group were lower than those in its control group. There was a positive correlation between T/NT ratio and HIF-1 expression in radiotherapy group and control group at diff erent time points. Conclusion: 99 m Tc-2-(2-methyl-5-nitro-1H-imidazol-1-yl) ethyl dihydrogen phosphate ( 99 m Tc 99 m Tc-MNLS tumor hypoxic imaging can evaluate the tumor hypoxic status of tumor-bearing mice after radiotherapy.

Background: Gastrointestinal stromal tumors (GISTs), which are the most common mesenchymal tumors of the digestive system, are classifi ed as very low, low, intermediate and high risk. The treatment and prognosis of GISTs vary according to the grade. Objectives: To investigate the capability of computed tomography (CT)-based texture analysis for predicting the grade of GISTs, and compare the fi ndings with a combination model consisting of CT signs and texture parameters. Patients and Methods: For this retrospective study, a total of 168 patients (training group: n = 117; validation group: n = 51) with pathologically proven GISTs were analyzed. Patients were randomly divided into the potential malignant and malignant group. Radiomics signature based on texture features and the combination model consisting of selected CT signs and texture parameters were developed with the least absolute shrinkage and selection operator (Lasso) regression. The prediction performance of models was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). Calibration was evaluated with the HosmerLemeshow goodness-of-fi t test. Results: Totally, 29 texture features and seven CT signs were extracted. Texture features of sphericity, compacity, contrast, and dissimilarity, and CT signs of size, and location were selected to develop the predictive models. The rad-and pre-scores were calculated for the radiomics signature and combination model based on the validation group. Both two models hold great prediction performance with AUCs of 0. 897 and 0. 959 (P < 0. 05), sensitivities of 76. 20% and 90. 50%, specifi cities of 90. 0% and 93. 30%, accuracies of 84. 30% and 90. 20%, respectively. The combination model performed better. Calibration curves showed no statistically signifi cant diff erences between the two models (P > 0. 05). Conclusion: The prediction models were validated to be valuable for risk grade of GISTs and may provide non-invasive and practical biomarkers for optimizing the treatment strategy and improving the prognosis. In addition, the combination model had more advantages than texture analysis alone.

Background: The computer-aided diagnosis (CAD) has been applied in multiple studies conducted recently in order to perform ultrasound (US) of the breast. There are several studies that have indicated that CAD is useful for improving the diagnostic performance in less experienced radiologists. However, there is no study on several readers analyzing the same lesions using a breast phantom and rare reliability studies. Objectives: To investigate the reliability of different readers using computer aided diagnosis (CAD) system in US for determining identical lesions in a breast phantom. Patients and Methods: From March 2016 to February 2017, six readers (three senior and three junior residents in the department of radiology) evaluated and analyzed breast phantom including 14 lesions. At the fi rst line study, three senior residents (3rd grade with more than one month of training for breast ultrasound [US]) and three junior residents (1st grade without breast US training) evaluated and analyzed the US and applied CAD for lesions in breast phantom, and they were able to make fi nal decisions by subjective combination. A month later, they conducted the second line study as they did the fi rst line study. We analyzed the inter-and intra-reader reliability and accuracy of US, CAD, and combinations (subjective, conjunctive, and disjunctive). Results: In the total of fi rst and second line studies of six readers, the kappa value of US (0. 609) was signifi cantly higher than CAD (0. 411). In the subjective combined conclusion, the kappa value was improved by the junior group. In the whole inter-and intrareader analysis, the kappa values of fi nal assessment of the senior and junior group were more variable on CAD than on US, especially in the junior group, and this result was statistically signifi cant. The area under the curve (AUC) of US, CAD, subjective, conjunctive, and disjunctive combination in seniors were all better than those of juniors. In all groups, the AUCs, sensitivities, and specifi cities were improved on conjunctive combined US with CAD. Conclusion: The combination US with CAD improved the reliability and diagnostic performance. The CAD results of the junior group were variable and inconsistent. Therefore, minimum training and experience for breast US is indispensable for the better use of breast CAD, and, combination US with CAD is useful for all readers.

Invasive aspergillosis typically occurs in immunocompromised patients and results in fatal complications. Musculoskeletal involvement of aspergillosis is extremely rare, therefore, when it occurs, its diagnosis and treatment could be delayed. In this paper, we report a rare case of primary invasive aspergillosis with radiologic findings in a patient with rheumatoid arthritis. A 57-yearold woman presented a palpable mass on the right hand with a previous medical history of long-term use of immunosuppressive agents due to rheumatoid arthritis. Magnetic resonance imaging showed a multilobulated and multiloculated cystic lesion with an enhancing wall. The wall of the cystic lesion showed low signal intensity on T2 weighted images and intermediate to high signal intensity on T1 weighted images. The mass was confi rmed as chronic granulomatous inflammation with multiple acute branching and septated fungal hyphae, consistent with invasive aspergillosis. When a superficial multicystic mass in the hand of especially immunocompromised patients is encountered, invasive aspergillosis should be included in the differential diagnosis, although it is rare.

Background: In the magnetic resonance imaging (MRI) of many tissues, apparent diffusion coefficient (ADC) values vary with age. In the literature, there are no studies in which normal cervix ADC values and their relationship with age is analyzed. Objectives: To evaluate whether changes occur in ADC values with aging in the uterine cervix with 3-Tesla MRI. Patients and Methods: Female patients aged between 18 and 70 years who were found to have lower abdominal diffusion-weighted magnetic resonance imaging (DWI) in the radiology database from December 2017 to May 2018 were evaluated. All DWI examinations were performed using a 3-T MR with 2 b values (b = 50, 800 s/mm ). A total of 161 patients were divided into two groups according to their menopausal status (premenopausal n = 106, postmenopausal n = 55). To evaluate the correlation between the age of the patient and the ADC values, Pearson correlation analysis was performed. Results: The mean age of the patients was 41. 4-11. 6 years. The mean ADC value was 1. 276-0. 25 mm 2 in the whole population. There was a negative correlation between age and ADC values. The mean cervix ADC value of premenopausal and postmenopausal patients was 1. 333-0. 23 mm2-3 /sec 10 2 and 1. 165-0. 25 mm/sec 10-3, respectively. There was a statistically significant difference between the groups in term of cervix ADC value (P < 0. 05). Conclusion: A negative correlation between aging and ADC values was found. Menopausal status has an effect on the ADC values of the cervix. These findings may indicate cellular and extracellular matrix changes in the cervix tissue with aging and menopausal status.

Background: Abdominal CT using a tube-current modulation technique may result in artifacts due to changes in the position of the patient’ s arms, resulting in poor image quality and excessive radiation exposure. To solve these problems, the patient’ s arm is positioned mainly on the head or outside the examination area. Objectives: An optimization method to acquire high-quality images in CT examination by comparing the radiation dose and image according to the change in arm position and the use of the tube-current modulation method in CT examination. Materials and Methods: To analyze the CT images, the mean, standard deviation (SD), and coeffi cient of variation (COV) of the Hounsfi eld unit (HU) of the CT were obtained by measuring the pixel values of the heart, chest, lung, and bone using region of interest (ROI) manage. The dose of computed tomography dose index (CTDI) and dose length product (DLP) according to the position of the arm. Results: The arms up position of CTDIvol and DLP values were lower than the arms down position. In the z-axis thickness modulation (Z-DOM), the tube current increased in the shoulders, decreased in the lungs, and increased in the abdomen. There was no artifact when the arms were raised, but an artifact was present when the arm was lowered. The calculated peak signal-to-noise ratio (PSNR) for the Z-DOM application in the CT scan of the anthropomorphic phantom by applying automatic exposure control (AEC) was 38. 21 dB. There was no signifi cant diff erence between SD and COV using Z-DOM and the fi xed tube current technique (P > 0. 05). Noise in the image increased when the arm was raised, and dose increased in the thyroid and upper chest. Conclusion: The position of the upper arms directly aff ects the image in the MDCT imaging of the anthropomorphic phantom. Therefore, it is possible to increase the quality of the image by reducing the amount of artifacts and the amount of radiation by orienting the arms upward. This optimal test method could be used in clinical practice to achieve high image quality and low noise in the MDCT of trauma patients.

Background: It is common for osteochondral lesions of the talus (OLT) to be associated with ankle injury, residual ankle stiff ness and pain after osteochondral injuries, and OLTs are most common in the dome of the talus. Before choosing the appropriate therapy based on diagnosis, it is necessary to determine if the OLT is a stabile lesion or not. More accurate diagnosis and classifi cations could be conducted to guide the clinical treatment. Objectives: To compare the accuracy rate and diagnostic indices of proton-density fat-saturation BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction in magnetic resonance systems from Siemens Healthcare) sequences from a small fi eld of view (FOV) surface coil and proton-density fat-saturation sequences without BLADE in a routine FOV using a boot-shaped coil on the magnetic resonance imaging (MRI) of OLT. Patients and Methods: One hundred and one patients with ankle pain for greater than 6 weeks and normal X-ray participated in this study. They were ready for diagnosis by arthroscopy and treatment following MR examination. All patients were scanned by two diff erent methods: (a) a coronal proton-density fat-saturated sequence with BLADE using a small FOV surface coil and (b) a coronal proton-density fat-saturated sequence without BLADE using a routine FOV boot coil. In this study, the arthroscopic results were regarded as the gold standard for assessing OLTs and were used to directly compare the ability of the two diff erent scanning methods to produce accurate fi ndings with regard to MR imaging of OLTs. Results: Of the 101 patients, 57 patients with cartilaginous injury were confi rmed by the results of arthroscopy, and 44 patients were without cartilaginous injury. Forty-eight lesions had the same grade with the small FOV BLADE sequence MRI and arthroscopy, while 37 lesions had the same grade on routine FOV MRI and arthroscopy among 57 patients with cartilaginous injury. Among MR fi ndings of 101 patients, the results of weighted Kappa, accuracy, sensitivity and specifi city were 0. 803, 90. 10%, 84. 21%, and 97. 73%, respectively between small FOV and arthroscopy; 0. 515, 75. 25%, 64. 91%, and 88. 64%, respectively between routine FOV and arthroscopy. The accuracy rate, sensitivity and specifi city of small FOV with BLADE were higher than routine FOV. Mc Nemar’ s test confi rmed that the accuracy, sensitivity and specifi city of small FOV BLADE were signifi cantly better than routine FOV (P < 0. 001). Greater values of small FOV compared to routine FOV appeared in sensitivity of 0. 94 vs. 0. 81 (MR normal and grade I), 0. 89 vs. 0. 77 (MR normal and grade I-IIA), 0. 90 vs. 0. 74 (MR normal and grade I-IIB), 0. 91 vs. 0. 75 (MR normal and grade I-III) and specifi city of 0. 98 vs. 0. 92 (MR normal and grade I), the same in specifi city of 0. 91 vs. 0. 91 (MR normal and grade I-IIA), 0. 80 vs. 0. 80 (MR normal and grade I-III), only smaller in specifi city of 0. 60 vs. 0. 80 (MR normal and grade I-IIB). Conclusion: Small FOV surface coil with BLADE sequence grading of OLT demonstrated a promising accuracy rate compared with arthroscopic diagnosis.

Myxofibrosarcoma is the most common soft tissue sarcoma that appears in the elderly, and mainly occurs in the trunks and extremities. However, myxofibrosarcoma of the head and neck is uncommon with a reported incidence of 2% to 4%, and there is no information in the literature regarding myxofibrosarcoma in the parapharyngeal space. Here, we present a rare myxofibrosarcoma case of the parapharyngeal space. Clinical features and imaging findings are nonspecific, and rarely in the head and neck area, so accurate preoperative diagnosis may be difficult. The diagnosis may be challenging, but the identification of tumor origin, location, extent, and anatomical relationships on MR images can be helpful to establish preoperative treatment plans.

Background: In order to reduce the occurrence of bone cement leakage, bone filling mesh container technique can be a prior choice for the treatment of vertebral metastases with damaged posterior margin of the thoracolumbar vertebral body. Objectives: The purpose of this retrospective study was to compare the efficacy and safety of percutaneous balloon kyphoplasty (PKP) and bone filling mesh containers (BFMCS) in the treatment of vertebral metastases with posterior vertebral body damage. Patients and Methods: This is a retrospective study. From October 2016 to January 2018, 40 cases (72 vertebral bodies) of thoracolumbar osteolytic metastases were treated with vertebroplasty. Among them, 20 cases (37 vertebral bodies) were treated with PKP (PKP group), and 20 cases (35 vertebral bodies) were treated with BFMCS (BFMCS group). The operation time of the two groups was recorded, and visual analog scale (VAS), Oswestry disability index (ODI), intraoperative bone cement leakage and complications were observed before operation and 1 day, 1 month and 6 months after operation. Results: All patients underwent successful operation. The operation time of the PKP group was 42. 65-7. 84 minutes, and 42. 95-8. 48 minutes in the BFMCS group (P = 0. 91). Both groups differed significantly when the results were compared with those measured before treatment. VAS dropped from 7. 50-0. 95 points before operation to 1. 20-0. 41 points at 6 months follow up in PKP group (P < 0. 001), in the BFMCS group VAS dropped from 7. 50-0. 94 points before operation to 1. 45-0. 51 points at 6 months after operation (P < 0. 001). The ODI of the PKP group dropped from 75. 80-4. 76 before operation to 12. 05-1. 47, 6 months after operation (P < 0. 001), ODI dropped from 75. 00-4. 34 before operation to 11. 60-1. 39 at 6 months follow up in the BFMCS group (P < 0. 001). In the PKP group, 15 vertebral bodies (40. 5%, 15/37) occurred bone cement leakage, but the patients had no clinical symptoms of bone cement leakage. Cement leakage occurred in one case in the BFMCS group. There were no complications such as pulmonary embolism, paraplegia or perioperative death. Conclusion: The application of bone-filling mesh container for treating patients with thoracolumbar osseointegrated metastases could significantly reduce the leakage rate of bone cement, and is similar to traditional PKP in pain relief and activity improvement.

Background: Severe tilt with embedded hook is a common obstacle to successful retrieval of the retrievable inferior vena cava (IVC) fi lter. One reason leading to retrieval failure is the guide wire and catheter that could not be guided between the IVC wall and fi lter neck. Objectives: The aim of this study is to investigate the feasibility of a modifi ed wire-loop technique for retrieval of inferior vena cava fi lters with severe tilt and embedded hooks. Patients and Methods: Between September 2013 and November 2017, 156 patients underwent IVC fi lter implantation including drum-type fi lter (OptEase) and conical fi lter (Celect). Preoperative CT angiography or intraoperative angiogram revealed that three drum-type fi lters and four conical fi lters tilted severely and could not be retrieved using a conventional snare technique. We performed a modifi ed wire-loop snare technique. The end of 5F pigtail catheter was cut off and remade to be fi shhook-like. The pigtail catheter and 0. 035-inch-long soft guide wire were introduced into the inferior vena cava (IVCF) through long sheath. A 5F vertebral catheter and a snare were advanced into the IVCF simultaneously. The pigtail catheter directed the guide wire to pass through the interstice of the cava wall and fi lter neck. The leading end of the wire was snared by 5F vertebral catheter and the snare to form a loop. Then the loop snared the hook. If there was no interstice between the fi lter neck and cava wall, the homemade catheter would then direct the guide wire to pass through the interstice of separate fi lter struts. The conventional technique was performed or the long sheath advanced over the wire-loop to retrieve the fi lter directly. Results: Four conical fi lters were retrieved by snaring the hook directly. The fi lter hook of drum-type fi lter was stretched away from the cava wall in two cases, and then, the conventional snare technique was performed successfully. The long sheath was advanced over the wire-loop to retrieve the fi lter directly in one case. Conclusion: The modifi ed wire-loop snare technique is simple and effective and can be used to retrieve both conical and drum-type fi lters with severe tilt and embedded hooks.

Although schwannoma may occur in any organ, it very seldom appears as an interpectoral lesion and rarely arises in the brachial plexus. We here report the case of a breast cancer patient with a schwannoma located in the interpectoral space that mimicked a metastatic lymph node with various imaging modalities, including ultrasonography, magnetic resonance imaging, and positronemission tomography/computed tomography. Awareness of its location and imaging features on various modalities is helpful for identifying schwannoma mimicking a metastatic interpectoral lymph node in breast cancer patients without axillary level I lymph node metastasis.

Background: In the absence of clear clinical and radiographic signs, detection of vertical root fractures in teeth receiving root treatment is an important clinical challenge. Restoration with posts form artifacts on the image and reduce the quality of conebeam computed tomography (CBCT) images. Objectives: The present study was conducted to assess the detection accuracy of CBCT system in normal mode compared to "Artifact Reduction" option. Materials and Methods: A total of 62 human premolars (31 teeth with vertical root fracture and 31 teeth without fracture) that had been extracted for orthodontic, and periodontal treatments were used. Teeth received root canal treatment in the usual way and prefabricated posts were placed in them. Fracture was created by an Instron machine in one group, and the other group was considered as control. CBCT was prepared from all samples both with and without artifact reduction option. Three observers assessed the images for vertical root fracture based on the scales of 5. Sensitivity, specifi city, positive and negative predictive values were measured, and compared using Mann-Whitney test at a signifi cant value of P < 0. 05. Results: Full diagnostic sensitivity, and specificity was higher in the group without artifact reduction option compared to the group with it. No signifi cant differences were found between groups in any diagnostic indices, including full and absolute sensitivity and specifi city, and positive and negative predictive values (P > 0. 05). Conclusion: The artifact reduction option creates no CBCT diagnostic difference in the presence of a post, and does not provide better diagnosis of vertical root fractures.

Background: A papillary thyroid microcarcinoma (PTMC) may have the characteristics of diff erent types of lesions, usually leading to preoperative ultrasound diagnosis. Therefore, new diagnostic methods need to be developed. Objectives: This study aimed to evaluate the advantages of the Korean thyroid imaging reporting and data system (TI-RADS) combined with contrast-enhanced ultrasound (CEUS) in diagnosing PTMC. Patients and Methods: In total, 143 patients who had a total of 150 micro space-occupying lesions of the thyroid and underwent conventional ultrasonography (US) and CEUS were enrolled. The diagnostic value of the benign nodule and PTMC by TI-RADS, CEUS and combined method were compared. The independent US and CEUS predictors for PTCM were determined and quantifi ed using logistic regression analysis. Results: The TI-RADS + CEUS combination had the highest accuracy (95. 10%), sensitivity (96. 74%), specifi city (94. 83%), positive prediction value (87. 92%) and negative prediction value (98. 02%), signifi cantly greater than that of TI-RADS alone (area under the curve [AUC]: 0. 930 vs. 0. 873, P < 0. 001; accuracy: 95. 10% vs. 89. 78%, P = 0. 032; sensitivity: 96. 74% vs. 86. 05%, P = 0. 041; positive predictive value [PPV]: 87. 92% vs. 76. 47%, P = 0. 029) and CEUS alone (AUC: 0. 930 vs. 0. 857, P < 0. 001; accuracy: 95. 10% vs. 86. 93%, P < 0. 001; negative predictive value [NPV]: 98. 02% vs. 90. 83%, P = 0. 047). Multivariate stepwise logistic regression showed that calcifi cation (odds ratio [OR] = 1. 586; 95% confi dence interval [CI]: 1. 037-2. 311; P = 0. 027), hypoechogenicity (OR = 1. 432; 95%CI: 0. 975-1. 925; P = 0. 035), and hypo-enhancement (OR = 2. 140; 95%CI: 1. 237-2. 840; P = 0. 019) were the optimal predictor for PTMC. Conclusion: TI-RADS in combination with CEUS has superior diagnostic effi ciency in the discrimination of micro-thyroid spaceoccupying lesions, which can improve the diagnostic accuracy of PTMC.

Background: Fat necrosis is a common finding after trauma or surgery of the breast. There are various presentations on imaging and differentiation from malignancy can be challenging. Objectives: To analyze early signs of fat necrosis on postoperative mammograms after the excision of benign and malignant findings in accordance to modern adjuvant treatment. Patients and Methods: A retrospective analysis was performed as part of an audit. Mammograms of 39 patients, who underwent surgical excision of benign disease, and 81 patients with cancer surgery, were reviewed. Adjuvant therapy, such as radiotherapy, chemotherapy and hormonal treatment, was noted. Results: Mean patient age was 54. 6-6. 5 years in the benign and 59. 8-7. 8 years in the malignant group. Mean lesion size did not differ between the groups (P = 0. 735). Development of fat necrosis on mammography follow-up was observed in 12. 8% (5/39) of the patients in the benign and in 32. 1% (26/81) of the patients in the malignant group (P = 0. 024). Mean follow-up time until the first sign of fat necrosis was 2. 6 years in the benign group and 2. 0 years in the malignant group (P = 0. 187). With radiation therapy-hormonal treatment 25 of 75 patients (33. 3%) developed fat necrosis. Hormonal treatment significantly influenced the development of fat necrosis in the malignant group (odds ratio [OR]: 0. 231; P = 0. 029). Four of 16 patients (25. 0%) having radiation and chemotherapy developed fat necrosis. Conclusion: Fat necrosis development was observed significantly more often in patients after breast cancer surgery and modern adjuvant treatment compared to benign breast surgery. However, hormonal adjuvant treatment seemed to lower the chance of fat necrosis development.