A Retrospective CBCT Study of the Relationship between Mandibular Symphysis Bone Density and Mandibular Growth Direction

Objective: The objective of this retrospective study was to investigate the relationship between mandibular symphysis bone density (BD) and mandibular growth direction in adolescent patients by facilitating the measurement of cortical and cancellous BDs at the mandibular symphysis using cone beam computed tomography (CBCT). Study Design: 224 adolescent patients (98 males and 126 females) were categorized by sex, age, and mandibular growth direction. Cortical and cancellous BDs were measured along with a sagittal slice at multiple locations. Results: Females exhibited higher cortical BD than males at menton (Me, P =0.002). Patients with a posterior growth direction exhibited a higher cortical BD than those with anterior and normal growth direction at Me (P <0.021, P <0.001, respectively), pogonion (Pog, P =0.037, P =0.037, respectively) and genion (Ge, P =0.007, P =0.008, respectively). Patients with a posterior growth direction exhibited a higher cortical BD than those with anterior growth direction at B point (P =0.009). Conclusions: Significant differences in BD were identified across anthropometric categories. These findings may be useful in determining mandibular growth direction in adolescents.

Pathological examination of CT findings of tumor infiltration to the periarterial plexus in pancreatic cancer.

644 Background: The radiographic diagnosis of tumor infiltration into the periarterial plexus in pancreatic cancer is important because it is related to the classification, however, it is difficult to distinguish the abnormal shadow along the artery caused by inflammation or cancer infiltration. The aim of this study is to investigate CT values of the abnormal shadow along artery could distinguish between inflammation and tumor invasion. Methods: Study 1: Of 26 patients who underwent DP-CAR between 2009 and 2018, we analyzed 19 patients who had dynamic CT and obtained sagittal slice taken 120 seconds after injection with less than 2.5 mm slice thickness. At first, we measured CT values at upper and lower point of CeA and CHA each sagittal slice using CT. Next, we evaluated tumor invasion at the upper and lower plexus of CeA and CHA in each section of the pathological specimen, and evaluated the relationship between the tumor invasion and the CT value. Study 2: Using these 19 patients and 40 patients who underwent DP for PDAC between 2010 and 2014, we analyzed the relation between CT value and long-term states. Results: Study 1: CT value was totally measured at the 606 points using 19 patients who underwent DP-CAR. At the 490 points, we did not observe cancer infiltration and fibrosis. At the 70 points, we observed fibrosis without cancer cells. At the 46 points, we observed cancer infiltration. CT value was significantly higher in the tumor infiltration group than that in the without cancer infiltration and fibrosis group (P < 0.01). Study 2: The best cut-off of CT value of the presence of cancer infiltration was 44.9 HU using ROC curve (AUC = 0.861). The median survival time of patients who had the points of CT value > 44.9 HU around arteries was significantly shorter than that of patients who did not have the points of CT value > 44.9 HU (2.17 vs. 4.55 years, p = 0.03). Conclusions: The CT value around the arteries was significantly higher in the points of pathological tumor infiltration than that in the points of fibrosis without cancer cells. The best cut-off CT value of the presence of cancer infiltration around arteries was 44.9 HU, and the presence of the point of CT value > 44.9 HU around arteries was associated with poor survival.

INVESTIGATION OF FIT OF THE INDIVIDUAL ABUTMENT TO THE VARIOUS PLATFORMS OF IMPLANTS ON SAGITTAL SECTION

Introduction. Modern implant systems have different types of connections between the implant and the abutment, in the area of which a microgap can be constructively formed, as a result of which dentists are faced with a loss of bone tissue and inflammatory processes in the area of dental implants. Objectives ― assessment of the accuracy of the marginal fit of an individual abutment to the implant platform on a sagittal slice. Methods. Two groups were formed according to the type of connection between the implant and the abutment (conical and planar). Individual abutments for all systems were made using CAD-CAM technology. Using the grinding machine Metaserv 25, sagittal sections of the abutment and implant were obtained. The study and cutting the compound was carried out on a TESCAN MIRA 3 autoemission electron microscope. Results. Using an electron microscope TESCAN MIRA 3, we obtained images of the surface of the connection of the abutment and the implant on a sagittal slice. When three-dimensional scanning of the studied samples were obtained volumetric images. Measurements of the microgap of the implant compound and abutment on the sagittal split showed that with an increase of x8000 in the first group with a conical connection, the figure varied from 0.27-3.46 microns. In the second group with a planar compound, the index varied from 6.50-9.70 microns. Conclusions. The ratio of the abutment to the implant with conical connections showed the best results in comparison with planar connections. Using CAD-CAM technology allows you to create prostheses with good marginal fit of the connection between the implant and the abutment.

Analisis Informasi Citra Antara Sekuens T2 FRFSE dengan T2 Propeller pada pemeriksaan MRI Cervikal Potongan Axial dengan Pesawat MRI GE Signa 1,5 T

Backgroud:research has been done on the difference of image information for T2 FRFSE sequences and T2PROPELLER in Radiology Installation of General Hospital Dr Moewardi. The aim of this study is to determine THE differences of the image information between T2 FRFSE sequences and T2PROPELLER sequences and determine the best sequence between T2 PROPELLER with T2 FRFSE in cervical MRI examination of Spine Axial Slice.MethodsThis research is a quantitative study with experimental approach in Radiology Installation Dr. Moewardi Hospital. Data is collected on examination MRI Cervical in 15 patients, after a Cervical MRI scanning with sagittal slice T2 FRFSE sequences, and then performed scanning T2 PROPELLER sequences on Axial slice. Presented to the three doctors radiologist to assess. Once the image judged by the three respondents, the data analyse by using SPSS 17.0 with Wilcoxon test.Results:the result showed obtained significance value 0,001 or p value 0,05 Which means that there are differences image information between T2 FRFSE sequences and T2 PROPELLER sequences. Sequens T2 PROPELLER better than sequens T2 FRFSE in MRI CervicalAxial slice.Conclusion:Mean value of the same rank on the anatomy of the vertebral body and the soft tissue of the neck are 5.50 and 4.00 , while the mean rank differently on intraforamen structure is 6.5 , nerve root is 5.56 , so that the spinal cord was 6.15 T2 PROPELLER still better.

Validating the distribution of specific ventilation in healthy humans measured using proton MR imaging

Specific ventilation imaging (SVI) uses proton MRI to quantitatively map the distribution of specific ventilation (SV) in the human lung, using inhaled oxygen as a contrast agent. To validate this recent technique, we compared the quantitative measures of heterogeneity of the SV distribution in a 15-mm sagittal slice of lung obtained in 10 healthy supine subjects, (age 37 ± 10 yr, forced expiratory volume in 1 s 97 ± 7% predicted) using SVI to those obtained in the whole lung from multiple-breath nitrogen washout (MBW). Using the analysis of Lewis et al. (Lewis SM, Evans JW, Jalowayski AA. J App Physiol 44: 416–423, 1978), the most likely distribution of SV from the MBW data was computed and compared with the distribution of SV obtained from SVI, after normalizing for the difference in tidal volume. The average SV was 0.30 ± 0.10 MBW, compared with 0.36 ± 0.10 SVI ( P = 0.01). The width of the distribution, a measure of the heterogeneity, obtained using both methods was comparable: 0.51 ± 0.06 and 0.47 ± 0.08 in MBW and SVI, respectively ( P = 0.15). The MBW estimated width of the SV distribution was 0.05 (10.7%) higher than that estimated using SVI, and smaller than the intertest variability of the MBW estimation [inter-MBW (SD) for the width of the SV distribution was 0.08 (15.8)%]. To assess reliability, SVI was performed twice on 13 subjects showing small differences between measurements of SV heterogeneity (typical error 0.05, 12%). In conclusion, quantitative estimations of SV heterogeneity from SVI are reliable and similar to those obtained using MBW, with SVI providing spatial information that is absent in MBW.

Endplates Changes Related to Age and Vertebral Segment

Endplate separations are defined as the presence of a space between the hyaline cartilage and the cortical bone of the adjacent vertebral body. This study evaluates endplate separations from the vertebral body and intervertebral discs and verifies if endplate separation is related to age and the spinal level. Groups were formed based on age (20–40 and 41–85 years old) and the vertebral segment (T7-T8 and L4-L5 segments). Histological analysis included assessment of the length of the vertebral endplates, the number and dimensions of the separations, and orientation of the collagen fibers, in the mid-sagittal slice. Two indexes were created: the separation index (number of separations/vertebral length) and separation extension index (sum of all separations/vertebral length). The results of the study demonstrated a direct relationship between the density of separations in the endplate and two variables: age and spinal level.

Nasofrontal Outflow Tract Visibility in Computed Tomography Imaging of Frontal Sinus Fractures

The choice of frontal sinus fracture treatment is based on multiple factors, one of which is injury to the nasofrontal outflow tract (NFOT). Computed tomography (CT) imaging of the NFOT can play an important role in the decision process. We sought to assess the visibility of the NFOT on CT scans in frontal sinus fractures. Patients with frontal sinus fractures (including the posterior table) receiving a CT scan from April 1st 2001 to December 31st 2009 were included. Scans were retrospectively assessed for available views (axial, coronal, and sagittal), slice thickness, inclusion of the anatomical NFOT region in the scanned area, and visibility of the NFOT. A total of 170 patients were included. In majority (71%) of patients NFOT was visible on one or more views, whereas in 33% ( N = 56) of patients had three complete views (complete anatomical NFOT region scanned in three views). In this subgroup, the ability to assess the NFOT increased to 89%. When selecting patients with three complete views of ≤ 2 mm slice thickness ( N = 47), the ability to assess the NFOT increased to 96%. In conclusion, when assessing the NFOT using CT imaging, having three complete views (axial, coronal, and sagittal) and a ≤ 2 mm slice thickness greatly increases the NFOT visibility.