Retroperitoneum ganglioneuroma: imaging features and surgical outcomes of 35 cases at a Chinese Institution

Background The preoperative evaluation is crucial for diagnosis and surgical plan of retroperitoneum ganglioneuroma (GN). In this study, we reviewed a relatively large series of histopathological proved retroperitoneum GN cases, summarized the imaging features and further depicted risk factors of increased surgical blood loss. Methods A total of 35 (18 male, 17 female) patients were retrospectively enrolled from January 2012 to June 2019 at our institution. Among them, 24 patients had undergone CT scans and 19 patients had undergone MR examination before treatment. The clinical and radiological features were analyzed and the relationships between image features and surgical blood loss were evaluated. Results The media age of the involved 35 patients was 40 years (range, 14–66 years). The histological tumor size was 10.12 ± 4.56 cm for average. Retroperitoneum GN was relatively low density on unenhanced CT images and showed delayed progressive enhancement on enhanced CT and MR images. The whorled sign could be seen in 14 patients. The vessel encasement sign could be found in 17 patients. Univariate analysis revealed maximal tumor size measured on axial image, maximal tumor size measured on coronal image, encasing one or both renal pedicles, encasing the aorta and/or vena cava and whorled sign on MRI showed significant difference between the blood loss ≥ 400 ml and blood loss < 400 ml group. Logistic regression further detected that maximal tumor size measured on axial images (OR: 1.12; 95% CI: 1.02–1.24; P = 0.023) and encasing one or both renal pedicles (OR: 22.39; 95% CI: 1.35–372.99; P = 0.030) were independently correlated with surgical blood loss. Conclusions Preoperative CT and MR imaging analysis was valuable for both diagnosis and surgical risk prediction of retroperitoneum GN.

Study on the Application of 1.5T Magnetic Resonance Imaging Image Fusion in the Staging of Rectal Cancer

Rectal cancer is a common gastric testicular malignancy, and surgical resection is the most effective treatment. The depth of local tumour filtration, lymph node metastasis and distant metastasis are all factors that influence the prognosis of rectal cancer surgery. MRI has the advantages of high-resolution, multidirectional, multi-angle, multiparameter imaging and zero radiation in soft tissue, so you can estimate the depth of tumour filtration and lymph node metastasis more accurately than ultrasound or CT. Today, it is a standard method for pre-operative imaging of rectal cancer. In this study, patients with rectal cancer have been studied from May 2020 to May 2021. 75 Patients were scanned at an arrow-shaped position and cross-sectional images, which are strictly vertical to the rectal wall, were designed after improvement at tumour level. The position of the coronal image is strictly vertical to the horizontal position. In this way, partial volume effects can be avoided and the depth of tumour filtration accurately evaluated. This helps surgeons determine the horizontal position of the tumor based on MRI images. To avoid the volume effect, the cross-section line must be vertical to the tumour axis. This study shows that in T3 tumours it is particularly important to measure the minimum level between the tumour and the rectal mesioma phase. The histology of the resected samples showed that if the distance between the tumor and the rectal mestrincular fascia exceeds 1 mm, the frequency of local recurrence is greatly reduced. If the distance between the tumor and the rectal mesiole fascia is less than 1 mm, the risk of local recurrence is greatly increased. Therefore, tumours with a straight mesosis of 1 mm or less margin-positive are called.

The Utility of Using Preoperative MRI as a Predictor for Intraoperative Pituitary Adenoma Consistency and Surgical Resection Technique

Objective Most pituitary adenomas are of soft consistency and can be resected during surgery with routine suction instruments. However, fibrous adenomas may require more aggressive techniques. The ability to predict consistency on magnetic resonance imaging (MRI) would improve preoperative preparation and may have implications on the extent of resection. Design A retrospective review of MRI and tumor histology of 50 consecutive patients who underwent endoscopic endonasal resection for nonfunctional adenomas was performed. Methods An intensity ratio was calculated based on quantitative MRI signal intensity of the adenoma and pons. Intraoperatively, a sequentially graded technique required for resection ranged from suction (R1) for softer tumors, curettes (R2) for tumors with intermediate consistency, and aspirators and/or other microinstruments (R3) for firmer tumors. Fibrotic content was determined from histologic collagen percentage, and rates of gross total resection (GTR) were calculated from postoperative imaging. Statistical analyses were performed to determine if resection classification could be predicted by intensity ratio or collagen percentage, calculate ratio of cut-off points for clinical use, and assess for correlation between intensity ratios and collagen percentage. Results Tumors with ratios < 1.6 on the T2-weighted coronal image and collagen content > 5.3% were likely to have required a more aggressive resection technique. Statistically significant lower rates of GTR and higher rates of perioperative complications were seen with such tumors. Conclusion Preoperative MRI analyses can be helpful but not definitive in predicting adenoma consistency. Fibrous adenomas, associated with higher collagen content, are more difficult to resect and have higher rates of subtotal resection.

MR Imaging of SLAP Lesions

Background: SLAP lesions of the shoulder are challenging to diagnose by clinical means alone. Interpretation of MR images requires knowledge of the normal appearance of the labrum, its anatomical variants, and the characteristic patterns of SLAP lesions. In general, high signal extending anterior and posterior to the biceps anchor is the hallmark of SLAP lesions. Common diagnostic criteria for a SLAP lesion by MR or MR arthrography include the following: presence of a laterally curved, high signal intensity in the labrum on a coronal image, multiple or branching lines of high signal intensity in the superior labrum on a coronal image, full-thickness detachment with irregularly marginated high signal intensity and/or separation >2 mm on conventional MRI or 3 mm on MR arthrography between the labrum and glenoid on a coronal image, and a paralabral cyst extending from the superior labrum. Methods: MR diagnosis of SLAP tears may be improved with provocative maneuvers, such as longitudinal traction of the arm or positioning of the shoulder in abduction and external rotation during imaging. The use of intra-articular contrast distends the joint similar to what occurs during arthroscopy and forced diffusion under the labrum may improve the ability to detect SLAP lesions that might not be seen with standard MR. Improved diagnostic accuracy for SLAP tears is seen with 3-T compared with 1.5-T MR imaging, with or without intra-articular contrast material. Conclusion: Regardless of MR findings, however, physicians should be cautious when recommending surgery in the patient with a vague clinical picture. The patient’s history, physical exam, and imaging evaluation all should be considered together in making the decision to proceed with surgery.

Weight-bearing anteroposterior radiograph of the ankle underestimates the severity of osteoarthritis when there is anterior subluxation of the talus

Category: Ankle Arthritis Introduction/Purpose: On weight-bearing lateral radiograph, anterior aspect of the ankle shows more narrowing than posterior aspect in the ankle osteoarthritis with anterior subluxation of the talus. However, weight-bearing anteroposterior radiograph of the ankle osteoarthritis with anterior subluxation of the talus often shows less severe joint space narrowing than the joint space in the narrowest anterior aspect of the ankle joint. (Fig.1). The purposes of this study were to compare the degree and shape of joint space narrowing in the anterior, middle and posterior aspect of the ankle by using weight-bearing CT and to investigate which area of the ankle was shown on plain weight-bearing ankle anteroposterior radiograph in the ankle osteoarthritis with anterior subluxation of the talus. Methods: We retrospectively evaluated patients who underwent surgery for ankle osteoarthritis in our clinic from January, 2017 to May, 2017. We included patients who showed ankle osteoarthritis with anterior subluxation of the talus in weight-bearing lateral radiograph. We determined anterior, posterior and middle coronal images in sagittal image of the weight-bearing CT.(Fig.1) Talar tilt, medial width of superior clear space(SCS), lateral width of SCS, width of medial clear space and obliteration ratio were measured on plain weight-bearing anteroposterior ankle radiograph, and the three coronal images. The obliteration ratio was obtained by obliteration-width / talus-width * 100.(Fig.1) The radiographic parameters of the anterior coronal image were compared with those on the middle and the posterior coronal image by using paired T-test. The intraclass coefficient was used to investigate which of the three coronal images showed best match with degree and shape of ankle osteoarthritis on the plain weight-bearing ankle anteroposterior radiograph Results: Seventy-one ankles from 71 patients were included in this study. The average age of patients in this study was 62.6 years (range: 19-82). The talar tilt on the anterior coronal image was significantly lower than that on the middle and posterior coronal images. The lateral width of SCS and the width of medial clear space on the anterior coronal image was significantly narrower than those on the middle and the posterior coronal image. The obliteration ratio on the anterior coronal image was significantly higher than that of the middle and the posterior coronal images (Fig.2). The intraclass coefficients indicated that the radiographic parameters on plain weight-bearing anteroposterior radiograph was most reliable with those on the middle coronal image among the three coronal images. Conclusion: Anterior area of ankle shows the most severe osteoarthritis and plain weight-bearing anteroposterior radiograph shows the best match to the middle portion of the ankle, when ankle osteoarthritis has anterior subluxation of the talus. Because middle area of ankle has less severe ankle osteoarthritis than anterior area of ankle in that kind of ankle osteoarthritis, plain weight-bearing radiograph may underestimate the severity of ankle osteoarthritis.

Lunate fractures and associated radiocarpal and midcarpal instabilities: a systematic review

The aim of this study was to analyse lunate fractures and any associated osseo-ligamentous injuries. A systematic review identified 34 cases. We identified carpal instabilities at the radiocarpal and midcarpal joints in volar and dorsal directions. Radiocarpal instabilities (10/34) were usually dorsoradial (8/10), with a transverse lunate fracture, best seen on a coronal image. Midcarpal instabilities (24/34) were usually volar (14/18), with a volar lunate shear fracture, best seen on a sagittal image. Instabilities were sub-classified into non-displaced, subluxated and dislocated. Associated fractures of the scaphoid and the radial and ulnar styloid processes were common. Lunate fractures without subluxation or dislocation had good outcomes with cast immobilization or fixation of associated fractures. Lunate fracture-subluxations are unstable injuries that are best managed with fixation of the carpal fractures. Lunate fracture-dislocations are complex injuries, requiring stabilization of the lunate, associated fractures and ligament injuries; complications are common and acute or delayed salvage procedures may be required.

Determining the Size of the Mental Foramen: A Cone-Beam Computed Tomography Study

Aim: Knowledge of the position of the mental foramen is important to prepare strategy when administering regional anesthesia, performing dental surgical procedures, endodontic treatments. Also, it is critical to analyze diameter of mental foramen in sagittal, coronal, and axial images. The aim of this retrospective study was to determine the diameter of the MF in different planes from CBCT images. Methodology: This study was designed at Department of Endodontics, Dicle University, Diyarbakır, Turkey. One hundred twenty three (67 female, 56 male) CBCT scans that met the study criteria were obtained. All images were obtained from i-CAT (Imaging Sciences International, Hatfield, PA). Data were analyzed using Student’s t-tests and Tukey HSD tests. Results: For the analysis of age, data were divided into four groups: 12–17, 18–29, 30–49, and ≥50 years. The data were also divided into two groups by gender. Axial and coronal image measurements were also divided into right and left. There was a statistical difference compared with females and males (p<0.05). In the coronal plane, the right region showed significant differences in measurements between the groups (p<0.05). In the axial plane, there was no statistically significant difference between them (p>0.05). The differences between the groups in the left region in the axial plane measurements were significant (p<0.05). Conclusions: Using CBCT imaging superimposition of anatomical structures can be eliminated. It is important that determine that the size of the mental foramen. This study is a retrospective study using CBCT from patient and find that the size of the mental foramen. How to cite this article: Falakaloglu S, Veis A. Determining the size of the mental foramen: A cone-beam computed tomography study. Int Dent Res 2017;7:20-25.