• Korean Journal of Radiology
• /
• v.25 no.6
• /
• pp.505-507
• /
• 2024

• Korean Journal of Radiology
• /
• v.25 no.6
• /
• pp.508-510
• /
• 2024

• Korean Journal of Radiology
• /
• v.25 no.5
• /
• pp.412-413
• /
• 2024

• Korean Journal of Radiology
• /
• v.24 no.12
• /
• pp.1200-1220
• /
• 2023

Dilated cardiomyopathy (DCM) is one of the most common types of non-ischemic cardiomyopathy. DCM is characterized by left ventricle (LV) dilatation and systolic dysfunction without coronary artery disease or abnormal loading conditions. DCM is not a single disease entity and has a complex historical background of revisions and updates to its definition because of its diverse etiology and clinical manifestations. In cases of LV dilatation and dysfunction, conditions with phenotypic overlap should be excluded before establishing a DCM diagnosis. The differential diagnoses of DCM include ischemic cardiomyopathy, valvular heart disease, burned-out hypertrophic cardiomyopathy, arrhythmogenic cardiomyopathy, and non-compaction. Cardiac magnetic resonance (CMR) imaging is helpful for evaluating DCM because it provides precise measurements of cardiac size, function, mass, and tissue characterization. Comprehensive analyses using various sequences, including cine imaging, late gadolinium enhancement imaging, and T1 and T2 mapping, may help establish differential diagnoses, etiological work-up, disease stratification, prognostic determination, and follow-up procedures in patients with DCM phenotypes. This article aimed to review the utilities and limitations of CMR in the diagnosis and assessment of DCM.

• Progress in Medical Physics
• /
• v.6 no.2
• /
• pp.3-12
• /
• 1995

A 50 $\mu\textrm{m}$ thick niobium filter and its quantitatively determined aluminum equivalent filter were evaluated for effects on entrance skin dose, image quality, and x-ray tube loading for three different tube voltages in radiology. There was no significant difference in the reducion in entrance skin dose and increase in tube loading between two filters while keeping radiographic contrast on the film. For the clinical use of the aluminum equivalent filter as an alternative to the niobium filter in radiology, aluminum equivalent filter thickness at the mid energy range of radiology, 90 kVp, was measured and the filter was applied to the other kVp values, 73 and 125 kVps, to evaluate the effect on the entrance skin dose and tube loading. There was no significant difference between two filter cases at the selected kVp. The aluminum filter with equivalent thickness can be used as an inexpensive alternative to the niobium filter.

• Imaging Science in Dentistry
• /
• v.33 no.2
• /
• pp.113-119
• /
• 2003

Purpose : To evaluate the relationship between morphometric analysis of bone microstructure from digital radiographic image and trabecular bone strength. Materials and Methods : One hundred eleven bone specimens with 5 mm thickness were obtained from the mandibles of 5 pigs. Digital images of specimens were taken using a direct digital intraoral radiographic system. After selection of ROI (100 × 100 pixel) within the trabecular bone, mean gray level and standard deviation were obtained. Fractal dimension and the variants of morphometric analysis (trabecular area, periphery, length of skeletonized trabeculae, number of terminal point, number of branch point) were obtained from ROI. Punch sheer strength analysis was performed using Instron (model 4465, Instron Corp., USA). The loading force (loading speed 1 mm/min) was applied to ROI of bone specimen by a 2 mm diameter punch. Stress-deformation curve was obtained from the punch sheer strength analysis and maximum stress, yield stress, Young's modulus were measured. Results: Maximum stress had a negative linear correlation with mean gray level and fractal dimension significantly (p<0.05). Yield stress had a negative linear correlation with mean gray level, periphery, fractal dimension and the length of skeletonized trabeculae significantly (p < 0.05). Young's modulus had a negative linear correlation with mean gray level and fractal dimension significantly (p < 0.05). Conclusions : The strength of cancellous bone exhibited a significantly linear relationship between mean gray level, fractal dimension and morphometric analysis. The methods described above can be easily used to evaluate bone quality clinically.

• Radiation Oncology Journal
• /
• v.9 no.2
• /
• pp.319-324
• /
• 1991

In our institution, a 76-year-old woman with primary urethral carcinoma was treated with remote afterloading high dose rate (HDR) interstitial brachytherapy using micro selectron Ir-192. In this paper, authors described the technical aspect of remote afterloading HDR interstitial brachytherapy for female urethal cancer.

• The Korean Journal of Nuclear Medicine
• /
• v.13 no.1_2
• /
• pp.37-43
• /
• 1979

This is an analysis of 39 patients studied at the Yonsei Medical Center from January, 1976 to March 1979. Of these35 patient were suspected of having hypothalamic insufficiency and subjected to the L-Dopa stimulation test to observe growth hormone sceretory function while four acromegaly patient received the glucose loading test and L-Dopa stimulation test. The results are as follows: 1. The basal level of GH in the various disease was as follows: a. The basal level was lower than the control level but was not statistically significant b. In diabetes the mean value tended to be higher than the control level but was not significant statistically c. In all four acromegaly patients the GH level was significantly higher than the control level 2. Of 13 patients with diabetes, nine had diabetic retinopathy, and of those nine, sir showed increased L-Dopa response. However, of the four non retinopathic DM patients, only one showed increased response to L-Dopa. 3. Two patients out of ten with Sheehan's syndrome responded to L-Dopa stimulation. 4. One Patient of eight with pituitary chromophobe adenoma responded to L-Dopa stimulation. 5. Four acromegaly patients revealed 3 acidophilic adenoma and one chromophobe adenoma histologically. Of patients receiving the L-Dopa stimulation test. Two showed a paradoxical response. Two patients who received the glucose loading test showed supressed response. 6. Of two craniopharyngioma patients, one showed increased GH response after L-Dopa stimulation. Increased response of GH after L-Dopa stimulation was seen in one of two craniopharyngioma patients and also in one of two patients with

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.48 no.1
• /
• pp.41-49
• /
• 2022

Objectives: We compared changes in fractal dimension (FD) and grayscale value (GSV) of peri-implant alveolar bone on digital panoramic radiography (DPR) and cone-beam computed tomography (CBCT) immediately after implant surgery and 12 months postoperative. Materials and Methods: In this retrospective study, 16 patients who received posterior mandibular area dental implants with CBCT scans taken about 2 weeks after implantation and one year after implantation were analyzed. A region of interest was selected for each patient. FDs and GSVs were evaluated immediately after implant surgery and at 12-month follow-up to examine the functional loading of the implants. Results: There were no significant differences between DPR and CBCT measurements of FD values (P>0.05). No significant differences were observed between FD values and GSVs calculated after implant surgery and at the 12-month follow-up (P>0.05). GSVs were not correlated with FD values (P>0.05). Conclusion: The DPR and reconstructed panoramic CBCT images exhibit similar image quality for the assessment of FD. There were no changes in FD values or GSVs of the peri-implant trabecular bone structure at the 12-month postoperative evaluation of the functional loading of the implant in comparison to values immediately after implantation. GSVs representing bone mass do not align with FD values that predict bone microstructural parameters. Therefore, GSVs and FDs should be considered different parameters for assessing bone quality.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.38
• /
• pp.31.1-31.7
• /
• 2016

Background: The objective of this retrospective study was to show results from platform-switched narrow-diameter implants in the posterior edentulous region, which we followed up for more than 1 year after functional loading. Methods: Ninety-eight narrow implants were inserted into 66 patients. After healing, fixed implant-supported prostheses were delivered to the patients, and Periotest and radiographic examinations were performed. After the first year of loading, the implant outcome was again evaluated clinically and radiographically using the Periotest analysis. Crestal bone loss and Periotest values (PTVs) were used to evaluate the effect of surgery, prosthesis, implant, and a host-related factor. A general linear model was used to statistically detect variables statistically associated with crestal bone loss and Periotest value. Results: We followed up on the implants over 1 to 4 years after loading; their survival rate was 100 %, and pronounced differences from PTVs were noted among jaw location, bone quality, and loading period. No difference was detected in bone loss among the variables studied. Bone loss after functional loading was $0.14{\pm}0.39mm$. The stability value from the Periotest was $-3.29{\pm}0.50$. Conclusions: Within the limitations of this study, judicious use of platform-switched narrow implants with a conical connection must be considered an alternative for wide-diameter implants to restore a posterior edentulous region.