Rim lesions in MS at 3T: clinical correlation and possible radiological alternatives for daily practice at lower field strength.

BACKGROUND AND PURPOSE: Paramagnetic rim lesions (PRLs) have been described as an imaging feature specific to multiple sclerosis (MS) using high-field strength phase-sensitive MR imaging. These lesions are suggested to reflect chronic active inflammation associated with greater disease severity and a more rapid disability progression. The aim of our study is to investigate the relationship between PRLs, clinical parameters, other radiological findings and disease progression. MATERIAL AND METHODS: This cross-sectional study included MS patients treated with teriflunomide, fingolimod, natalizumab or ocrelizumab for at least 2 years. PRLs seen at 3T MRI were analysed and correlated with clinical data and radiological progression, defined as an increase of the T2/FLAIR-lesion load during therapy. In the search for alternatives for these PRLs, we defined two additional radiological markers: 'FLAIR-bullet lesions', and on post-contrast black-blood (BB) images, 'BB-bullet lesions'. RESULTS: We included 84 MS patients of whom 27 (32 %) had at least 1 PRL. PRLs were associated with radiological progression under therapy (p=0.039) and higher clinical disability scores, although only significant for 9-Hole Peg Test (p=0.023). Patients with FLAIR-bullet or BB-bullet lesions at 3T MRI had a higher chance of PRL (p<0.001) with a likelihood ratio of 13.2 for FLAIR-bullets and 12.6 for BB-bullet lesions, thanks to the high negative predictive value of respectively 83 % and 90 %. CONCLUSION: PRLs are associated with an increase of T2/FLAIR-lesion load under therapy and unfavourable clinical outcome. Our newly defined 'bullet lesions' are associated with PRLs and might be an interesting MRI marker for centres without access to high-field SWI images.

MRI compatibility of orthodontic brackets and wires: systematic review article.

BACKGROUND: Before the magnetic resonance imaging (MRI) examination fixed orthodontic devices, such as brackets and wires, cause challenges not only for the orthodontist but also for the radiologist. Essentially, the MRI-safe scan of the fixed orthodontic tools requires a proper guideline in clinical practice. Therefore, this systematic review aimed to examine all aspects of MRI-safe scan, including artifact, thermal, and debonding effects, to identify any existing gaps in knowledge in this regard and develop an evidence-based protocol. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement was used in this study. The clinical question in "PIO" format was: "Does MRI examination influence the temperature of the orthodontic devices, the size of artifacts, and the debonding force in patients who have fixed orthodontic bracket and/or wire?" The search process was carried out in PubMed, PubMed Central, Scopus, and Google Scholar databases. The search resulted in 1310 articles. After selection according to the eligibility criteria, 18 studies were analyzed by two reviewers. The risk of bias was determined using the Quality In Prognosis Studies tool. RESULTS: Out of the eligible 18 studies, 10 articles examined the heating effect, 6 were about the debonding effect, and 11 measured the size of artifact regarding brackets and wires. Considering the quality assessment, the overall levels of evidence were high and medium. The published studies showed that heating and debonding effects during MRI exposure were not hazardous for patients. As some wires revealed higher temperature changes, it is suggested to remove the wire or insert a spacer between the appliances and the oral mucosa. Based on the material, ceramic and plastic brackets caused no relevant artifact and were MRI-safe. Stainless steel brackets and wires resulted in susceptibility artifacts in the orofacial region and could cause distortion in the frontal lobe, orbits, and pituitary gland. The retainer wires showed no relevant artifact. CONCLUSIONS: In conclusion, the thermal and debonding effects of the fixed orthodontic brackets and wires were irrelevant or resoluble; however, the size of the artifacts was clinically relevant and determined most significantly the feasibility of fixed brackets and wires in MRI examination.

Smoldering lesions in MS: if you like it then you should put a rim on it.

PURPOSE: In multiple sclerosis (MS), chronic active/smoldering white matter lesions presenting with hypointense rims on susceptibility-weighted imaging (SWI) of the brain have been recognized as an important radiological feature. The aim of this work was to study the prevalence of paramagnetic rim lesions (RLs) in MS patients in a clinical setting and to assess differences in demographic and clinical variables regarding the presence of RLs. METHODS: All 3 T brain magnetic resonance (MR) studies performed in MS patients between July 2020 and January 2021 were reviewed. In all patients, RLs were assessed on three-dimensional (3D) SWI images and the T2 FLAIR lesion load volume was assessed. Demographic, laboratory (oligoclonal bands in CSF), and clinical data, including functional status with Expanded Disability Status Scale (EDSS), were retrieved from the clinical files. RESULTS: Of the 192 patients, 113 (59%) presented with at least 1 RL. In the RL-positive group, the mean RL count was 4.81 ranging from 1 to 37. There was no significant difference in the number of RLs between the different types of MS (p = 0.858). Regarding the presence of RLs, there were no significant differences based on gender (p = 0.083), disease duration (p = 0.520), treatment regime (p = 0.326), EDSS score (p = 0.103), and the associated T2 FLAIR lesion load volume. CONCLUSION: SWI RLs were frequently detected in our cohort regardless of the MS type, T2 FLAIR lesion load volume, demographic features, disease duration, or clinical score. Our results suggest that RLs are not associated with more severe forms of the disease. Today, RLs can be seen on 3 T 3D SWI, although this is not a clinical standard sequence yet. Therefore, it should be considered an additional helpful MR sequence in the diagnostic workup of MS, although more studies are warranted to establish the role of RLs as prognostic markers.

Comparison of hyoid bone morphology between obstructive sleep apnea patients and healthy individuals.

OBJECTIVE: We aimed to find morphological properties of the hyoid bone, which are predominant among the patients diagnosed with obstructive sleep apnoea (OSA), and compare them with healthy individuals. METHODS: A total of 67 cone-beam computed tomography (CBCT) image sequences of patients (44 males, 23 females) diagnosed with OSA and a total of 70 multislice computed tomography (MSCT) data of non-OSA patients (45 males, 25 females) were selected in this study. DICOM images were imported into InVivo 5.1.2 (Anatomage) software. The position of the hyoid bone relative to the C3 and C4 cervical vertebrae, as well as its morphological type (B, V, U, H, D, HK-type) and its total volume was determined. RESULTS: The volumetric values of the hyoid bone of OSA patients (2384.49 ± 682.073 mm3 ) were significantly (P < .001) lower compared to the values derived from non-OSA patients (2952.96 ± 932.5 mm3 ). The difference was independent of gender, and volumetric values showed a strong significant (P < .01) difference between male OSA and non-OSA (2709.18 ± 608.05; 3157.87 ± 926.5 mm3 ) and female OSA and non-OSA patients (1763 ± 242.51 2584; 2584.12 ± 840.21 mm3 ), as well. In the case of B and V-types, the volumetric values showed significant differences (P < .05), when the OSA (2300,77 ± 622; 2166 ± 312 mm3 ) and non-OSA patients were compared (2823,48 ± 780; 3216 ± 463 mm3 ). CONCLUSION: Our results suggest that the volume of the hyoid bone might be a potential biological marker for OSA, especially in the case of B and V hyoid bone types.

[Planning options of reconstructive and orthognathic operation by means of three-dimensional imaging]. / Arcrekonstrukciós és orthognath mutétek tervezési lehetoségei háromdimenziós képalkotói módszerekkel.

We summarize up-to-date planning technics of orthognathic and reconstructive surgery operation which appeared with three-dimensional imaging, using literature data and some clinical examples. In many cases, orthognathic and reconstructive operations mean the only treatment of facial deformity caused by tumour, traumatic injury or congenital anomaly. In this field, radiology plays an important role not only in the diagnosis but also in the planning of the treatment. With the appearance of cone-beam computed tomography (CBCT), the previously used two-dimensional cephalometric analysis on lateral cephalogram was changed for three-dimensional cephalometric measurements. The first step of the adaptation was the lateral and frontal x-ray images generated from the CBCT database and later the volume rendered surface and segmentation technics provided the moving of the facial bones in three dimensions which meant virtual surgical planning. With the development of CAD/CAM technic and the three-dimensional printing, many opportunities became available, such as preoperative bending splints and plates and printed surgical model for the tangible planning. The progress of imaging facilitated the individual, accurate, and reliable planning which significantly determines the success of the treatment. Orv Hetil. 2018; 159(39): 1584-1592.

Multiple microlithiasis in bilateral parotid glands as the initial clinical manifestation of primary Sjögren's syndrome.

We report a rare case of Sjögren's syndrome (SS) with multiple microliths in the bilateral parotid glands. A 41-year-old man presented to our department with mild pain in the region of the right parotid gland. The dental examination was negative except for the parotid regions. The right region was moderately swollen and the left mildly swollen. Plain radiography revealed multiple calculi in the bilateral parotid glands. Ultrasonography showed heterogenic parenchyma, with microliths and cystic lesions in the parotid glands and heterogenic echotexture in the submandibular glands. Immunologic tests and the Schirmer test confirmed the diagnosis of SS. As the patient had no classic symptoms of SS, the bilateral multiple microliths were the first sign, facilitating the final diagnosis. Early diagnosis of SS is highly relevant because the proper therapy can be initiated. Adequate follow-up and, especially, control of the disease activity by identifying the predictive factors, are the primary objectives of SS management, enabling personalized treatment of this malignant disease. This case is a good example of how detection of calcifications in the bilateral parotid glands by plain radiography can help diagnose SS at an early stage.

Landmark-based midsagittal plane analysis in patients with facial symmetry and asymmetry based on CBCT analysis tomography.

PURPOSE: Reconstruction of the facial midplane is relevant in anthropometry, orthodontics, maxillofacial surgery, and the accurate measurement of symmetry deviation is relevant in many fields of medicine especially when planning surgical treatment. In the literature, three different means of midplane generation have been published; however, there is currently no consensus regarding the approach to use. Morphometric methods are used to determine the true midsagittal plane (MSP), but its use in clinical practice is difficult. A regression plane based on N­ANS-PNS landmarks reportedly approximates the morphometric MSP. As these points are vulnerable, we investigated which combination of landmarks can be substituted in symmetric and asymmetric faces. PATIENTS AND METHODS: Thirty symmetric and 30 asymmetric faces were analyzed on cone-beam computed tomography scans. A total of 50 regression planes were generated based on three unpaired landmarks and 35 regression planes were generated based the midpoints of paired landmarks. The Na-ANS-PNS plane was used as reference plane, and the mean angle between it and each generated MSP was calculated. The differences from the reference plane were compared by t­test between the groups. RESULTS: In the symmetric group, 86% of angles deviated by <5° using unpaired points, whereby 74% of angles deviated by <5° for paired points. Between the two groups 50% of planes from midline points, and 77% of planes from paired points were significantly different. All planes deviated more in the asymmetric group. CONCLUSIONS: The N­ANS-PNS reference plane can be substituted with the following combinations: ANS-G-Ba, ANS-G-S, ANS-S-De, PNS-G-Ba, PNS-S-Ba, PNS-ANS-G, and PNS-N-Ba.

Lower face cephalometry based on quadrilateral analysis with cone-beam computed tomography: a clinical pilot study.

OBJECTIVE: As most orthognathic surgeries focus on the lower face, the aim of this study was to transfer previously developed two-dimensional cephalometry-which is useful for surgeons in the orthognathic surgery of the lower face-to three-dimensional (3D) cephalometry by using cone-beam computed tomography (CBCT). We selected the quadrilateral lower face analysis developed by the surgeon Di Paolo, who focused only for the lower face and mentioned that data in millimeters are more easy to use than angles for surgeons. Additionally, we wanted to create a 3D lower face analysis approach based on quadrilateral analysis and establish a reference table for surgical planning. STUDY DESIGN: Three investigators assigned 16 landmarks on CBCT images from 30 patients with normocclusion. Intra-class correlation coefficients (ICCs) and standard deviations (SDs) were calculated according to each landmark. The maxillary and mandibular lengths and widths and the anterior and posterior lower facial heights (ALFH and PLFH) are presented as means and SDs. The asymmetry of the face was calculated with paired t test, and the coherence of the lower face was assessed with correlation coefficients (r) and regression models. RESULTS: The ICCs were ≥0.90, and the SDs of the landmarks were lower than 1.00 mm, except for the J-point, which was located at the junction of the anterior border of the ramus and the corpus of the mandible. The SDs of linear measurements were 3.06-5.20 mm, and there was no significant facial asymmetry. The r among the structures was greater than 0.3 in 13 of 15 assessments. Based on these values, we could establish a floating norm of the lower face using the following five regressions: one linear regression for the mandibular length, two quadratic models for the ALFH and PLFH, and two multivariate regressions for the posterior widths of the maxillae and mandible. CONCLUSION: The adaptation of quadrilateral analysis can provide accurate 3D characterization of the morphology of the lower face and the floating norm based on millimeter values, which is practical for surgeons. As the 3D extension of quadrilateral analysis could provide references of the lower face, which might be an accurate 3D approach for presurgical planning, the further investigation in bigger sample would be relevant in the practice.

[Di Paolo's cephalometrical analysis of lower face by means of Cone-Beam CT]. / Az alsó archarmad Di Paolo-féle vizsgálata Cone-Beam CT adatállományon.

OBJECT: 3D cephalometry is often the only way to set up accurate diagnosis and treatment plan in the field of reconstructive surgery. In these cases complement exposures are needed beyond common cephalograms with higher accuracy than conventional Cone-Beam CT. Consequently the aim of our study was to perform a complex 3D cephalometry. As the first step of this approach, was the 3D adaptation of DiPaolo's Quadrilateral technique, and to determine norms of references in lower face by means of CBCT. METHOD: Thirty non-orthodontic CBCT scans were selected for the digitalization. The most important inclusion criteria was Class I occlusion. Locations of 55 landmarks were signed three times by three observers by means of Cranio Viewer software. RESULTS: However Quadrilateral analysis contains only millimetric values we also integrate angles in the 3D version to determine the width of maxilla and mandible. In the 2D examination--where landmarks were projected to the middle plane. The SDs of the lengths were between 2,66 mm and 5,20 mm. The ratios of normodivergent lower face were significant different from the one by DiPaolo. In 3D adaptation there were no significant differences between the measurements of the two sides (p ≥ 0.05). We found mostly strong and significant correlations between each anatomical structure except of angles. CONCLUSION: Creation of 3D Quadrilateral cephalometry by means of strong correlation and norms of Class I occlusion provide a practical, reliable method to measure also the transversal asymmetry of lower face which is necessary part of 3D cephalometry.

[Report of the Hungarian Vascular Registry's data of infrarenal aortic aneurysms (2010-2014)]. / Magyarországon végzett infrarenalis aortaaneurysma-mutétek eredményei az Érsebészeti Regiszter adatai alapján (2010-2014).

INTRODUCTION: The Hungarian Society for Vascular Surgery decided to analyse and publish regularly the data of the Hungarian Vascular Registry. AIM: The aim of the authors was to present the outcome of infrarenal aortic aneurysm surgeries performed during the past five years. METHOD: Prospectively collected multicentric data obtained from the Hungarian Vascular Registry between January 1, 2010 and December 31, 2014 were analysed retrospectively. Statistical analysis was performed using Fisher's exact test and odds ratio calculation. RESULTS: It was found that 16.72% of the 1435 operations were performed for ruptured aneurysms. Five institutes having the highest capacity performed 78.4% of the operations. In the ruptured aortic aneurysm group the age of patients was 71.77±9.82 years (mean±SD), and perioperative mortality was 33.75%. In the intact aortic aneurysm group the age of patients was 69.50±8.46 years and the perioperative mortality was 3.51%. In both groups perioperative mortality (ruptured: p<0,05, OR = 0.11; intact: p<0.05, OR = 0.26) and the length of hospital stay (ruptured: p<0.05, OR = 4.55; intact: p<0.001, OR = 4.27) were significantly lower in patients who had endovascular repair compared to those with open repair. In both groups perioperative mortality (ruptured: p<0.0001, OR = 0.32; intact: p<0.0001, OR = 0.23) and length of hospital stay (ruptured: p<0.05, OR = 3.16; intact: p<0.001, OR = 3.84) were significantly lower in the five institutes having the highest capacity than in the remaining institutes. CONCLUSIONS: In patients having endovascular repair and in institutes with high capacity the perioperative mortality and length of hospital stay were significantly lower.

Measurement of orbital volume after enucleation and orbital implantation.

INTRODUCTION: This article reports experience relating to the measurement of orbital volume by means of cone beam computed tomography (CBCT) and Cranioviewer program software in patients who have undergone enucleation and orbital implantation. PATIENTS AND METHODS: CBCT scans were made in 30 cases, 10 of which were later excluded because of various technical problems. The study group therefore consisted of 20 patients (8 men and 12 women). The longest follow-up time was 7 years, and the shortest was 1 year. In all 20 cases, the orbital volume was measured with Cranioviewer orbital program software. Slices were made in the ventrodorsal direction at 4.8 mm intervals in the frontal plane, in both bony orbits (both that containing the orbital implant and the healthy one). Similar measurements were made in 20 patients with various dental problems. CBCT scans were recorded for the facial region of the skull, containing the orbital region. The Cranioviewer program can colour the area of the slices red, and it automatically measures the area in mm. RESULTS: In 5 of the 20 cases, the first 4 or all 5 slices revealed that the volume of the operated orbit was significantly smaller than that of the healthy orbit, in 12 cases only from 1 to 3 of the slices indicated such a significant difference, and in 3 cases no differences were observed between the orbits. In the control group of patients with various dental problems, there was no significant difference between the two healthy orbits. The accuracy of the volume measurements was assessed statistically by means of the paired samples t-test. SUMMARY: To date, no appropriate method is avaliable for exact measurement of the bony orbital volume, which would be of particular importance in orbital injury reconstruction. However, the use of CBCT scans and Cranioviewer orbital program software appears to offer a reliable method for the measurement of changes in orbital volume.