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[en] Echocardiographic evaluation of right ventricular (RV) function is a challenge due to the complex anatomy of the RV. Several transthoracic echocardiographic methods have been suggested for the quantification of RV function. However, many of the parameters are time consuming and need dedicated hardware and software. We suspected that the majority of the established markers are not used on a wide basis. In a multinational online survey, we evaluated the use of current clinical standards for the quantification of RV function in clinical practice. Through the network of an Ultrasound Online Teaching Platform, echocardiographers were invited to participate in an open online survey. The participants were asked about the parameters (eyeballing, TAPSE, S′, fractional area change, RIMP, 3D-EF, dp/dt, longitudinal strain) they used in clinical practice. A total of 1150 participants from 109 countries completed the survey. Only eyeballing (72%), TAPSE (69%), and S′ (31%) were commonly used in clinical routine. These methods were applied significantly less common in low-income economies when compared to high-income economies. Twenty-three percent of all participants stated to rely on eyeballing only, when evaluating RV function in clinical routine. New technologies, such as global longitudinal strain (3%) and 3D echocardiography (1%) were rarely applied independent of region and economic strength. Eyeballing and TAPSE are the most widely used methods in echocardiography for the assessment of RV function. Although advanced parameters such as longitudinal strain and 3D echocardiography were shown to be highly accurate, they are rarely used in clinical routine.
[en] Abdominal visceral artery aneurysms (VAA) include true and false aneurysms. The majority are asymptomatic and are discovered on cross-sectional imaging performed for unrelated clinical indications. With the maturation of techniques and devices used for embolization procedures and the treatment of aneurysms in other locations, most VAAs are now suitable for treatment by minimally invasive transcatheter techniques. The choice of technique used greatly depends on the local anatomy of the VAA and the experience of the interventional radiologist in complex vascular interventional techniques.
[en] Twenty patients with congenital aortic stenosis excluding valvular stenosis with studied between April 1980 and April 1984 at Seoul National University Hospital. The clinical and radiologic findings with the emphasis on the cineangiographies were analyzed separately according to the type of aortic stenosis as subaortic and supravalvular aortic stenosis. The summaries of the analysis are as follows: 1. Among the 20 cases, 12 cases were subaortic stenosis and 8 cases were supravalvular stenosis. 2. The anatomic types of subaortic stenosis were the discrete membranous type (8 cases), the fibromuscular type (2 cases) and the tunnel type (2 cases). 3. The obstruction of subarotic types was usually severe, and the median left ventricular to aortic systolic pressure gradient was 60 mmHg, and associated cardiac defects were found in 10 cases (84%), an incidence greater than that reported in most other large series. 4. The anatomic types of 8 cases of supravalvular aortic stenosis were mainly focal type (7 cases) and 1 case of diffuse hypoplastic type. 5. The median left ventricular to aortic systolic pressure gradient of supravalvular stenosis was 75 mmHg, and associated anomalies were seen in 6 cases (75%) with 3 cases of suspected mental retardation and facial abnormalities without definite hypercalcemia. 6. For accurate diagnosis of congenital aortic stenosis, retrograde left ventricular angiograms obtained in axial projections are of crucial importance in demonstration of anatomic types of stenosis and associated anomalies. And supravalvular arotic injection is sometimes helpful to outline the anatomy of the valve and to evaluate the degree of aortic regurgitation.
[en] To develop a new subtraction program for registering digital images based on the correspondence of anatomic structures. The digital periapical images were obtained by Digora system with Rinn XCP equipment after translation of 1-16 mm, and rotation of 2-20 at the premolar and molar areas of the human dried mandible. The new subtraction program, NIH Image program and Emago/Advanced program were compared by the peak-signal -to noise ratio (PSNR). The new subtraction program was superior to NIH Images program and Emago/Advanced program up to 16 mm translation and horizontal angulation up to 4. The new subtraction program can be used for subtracting digital periapical images
[en] Introduction: Anatomy has long been regarded as an integral part of the core curriculum. However, anecdotal evidence suggests that long-term retention of anatomy knowledge may be deficient. This study aims to evidence whether student radiographers demonstrate the same level of knowledge of anatomy after a period of time has elapsed and to correlate to approaches to learning and studying. Methodology: A repeated measures design was utilised to measure retention of anatomy knowledge for both MCQs and short-response answers to a Practical Radiographic Anatomy Examination; alpha value p < 0.05. Fifty-one students from levels 2 and 3 were retested after a time lapse of 10 and 22 months respectively. The students were not aware that their knowledge was being retested. Approaches to learning and studying were measured using the ASSIST inventory. Results: Statistical analysis found no difference in performance on MCQ assessment, in either the combined sample or levels 2 and 3 separately, from baseline to retention occasions; average retention rate being 99%. However, a statistical difference in performance on PRAE assessment was found, with level 2 experiencing a larger reduction in scores; retention rate of 67% compared to level 3 at 77%. The students perceived themselves to be principally strategic in their approach to learning and studying but no strong relationships were found when correlated to test scores. Conclusion: The student radiographers in this study demonstrated varied anatomy retention rates dependent on assessment method employed and time interval that had elapsed. It is recommended that diverse teaching and assessment strategies are adopted to encourage a deeper approach to learning and studying.
[en] Abdominal aortic aneurysms located around the major branch of the aorta were treated surgically rather than by endovascular treatment due to the complex anatomy. Recently, the treatment modality evolved towards a customized stent-graft. We report on a case of a mycotic pseudoaneurysm originating in the abdominal aorta at the level of superior mesenteric artery, which was treated with a customized stent-graft.
Introduction and objectivesKnowledge of the pyelocaliceal system anatomy is essential for the safe and successful performance of endourologic procedures. The purpose of this study was to provide a better understanding of the full three-dimensional pyelocaliceal system anatomy.
MethodsMorphometric parameters of the three-dimensional reconstructions of computed tomography intravenous urography scans (n = 25 scans) were analyzed. Both kidneys were divided into three equal-sized segments (US: upper segment, MS: mid segment, LS: lower segment). Infundibular length (IL), infundibular width (IW), the number of calyces, and the transverse orientation in hours of a clock of each calyx as well as the dimension of the pyelum were determined.
ResultsThe mean upper IL (n = 92) was longer than the middle (n = 154) and lower IL (n = 112) (30.6 ± 7.9 mm vs. 16.4 ± 7.7 mm vs. 16.0 ± 6.0 mm, respectively; P = < 0.0001). IW was significantly smaller in the MS [3.7 ± 1.9 mm], followed by the US [4.6 ± 1.9 mm], and the LS [4.9 ± 2.2] in the increasing order. No correlation was found between IL and IW (Pearson correlation coefficient = 0.1). The US calyces were predominantly orientated lateral (8-10 o’clock: 44.5%) and medial (2–4 o’clock: 30.5%), in the MS lateral (8–10 o’clock: 87.6%) and anterolateral in the LS (9–12 o’clock: 67.9%). 74% of the kidneys consisted of 6–8 calyces (mean 7.2 ± 1.4, range 4–10), with the majority of the calyces in the MS (3.1 ± 0.8) followed by the LS (2.24 ± 0.8), and US (1.8 ± 0.7). There were no statistical differences between the right and left kidneys in terms of IL (P = 0.112) and number of calyces (P = 0.685).
ConclusionAnatomic differences between the three segments of the pyelocaliceal system in terms of IL, IW, calyces number, and orientation are seen and should be considered when performing an endourologic procedure.
[en] The author measured the distance from mental foramen to the occlusal plane and classified the positional frequency of mental foramen to the tooth site using topography. The results were obtained as follows; 1. Of 964 mental foramen taken, the common site was in 2nd premolar region showing 64.08 percent in right and 57.17 per cent in left site. 2. The average distance from occlusal plane to the upper border of premolar region was 23.20 mm and lower border was 25. 07 mm. 3. The positional variation of mental foramen was that 4.77 percent were located above the apex of the nearest tooth, 50.42 per cent were located at the apex of the nearest tooth and 44.81 percent were located below the apex of the nearest tooth.
[en] This study was performed to evaluate possible variations in maxillary and mandibular bone texture of normal population using the fractal analysis, particles count, and area fraction in intraoral radiographs. Periapical radiographs of patients who had full mouth intraoral radiographs were collected. Regions of interest (100X100 pixels) were located between the teeth of the maxillary anterior, premolar, and molar area, as well as the mandibular anterior, premolar, and molar areas. The fractal dimension (FD) was calculated by using the box counting method. The particle count (PC) and area fraction (AF) analyses were also performed. There was no significant difference in the FD values among the different groups of age, gender, upper, and lower jaws. The mean FD value was 1.49±0.01. The mean PC ranged from 44 to 54, and the mean AF ranged from 10.92 to 11.85. The values of FD, PC, and AF were significantly correlated with each other except for the upper molar area. According to the results, patients with normal trabecular pattern showed a FD of approximately 1.5. Based on these results, further investigation would be recommended if the FD value of patient significantly different from this number, since the alteration of this value indicates microstructural modification of trabecular pattern of the jaws. Additionally, with periapical radiographs, simple and cost-effective, PC and AF could be used to assess the deviation from the normal.