PURPOSE: The aim of this study was to evaluate the thickness of buccal and palatal alveolar bone and buccal bony curvature below root apex in maxillary anterior teeth of Korean adults using Cone-beam CT images. MATERIAL AND METHODS: The 3D image was reconstructed with dicom file obtained through CBCT from 20 - 39 year old Korean subjects (n = 20). The thickness of buccal and palatal plate, root diameter, the buccal bony curvature angle below root apex and the distance from root apex to the deepest point of buccal bony curvature were measured on maxillary anterior teeth area using OnDemand3D program. RESULTS: Mean thickness of buccal plate 3 mm below CEJ was 0.68 +/- 0.29 mm at central incisor, 0.76 +/- 0.59 mm at lateral incisor, and 1.07 +/- 0.80 mm at canine. Mean thickness of palatal plate 3 mm below CEJ was 1.53 +/- 0.55 mm of central incisor, 1.18 +/- 0.66 mm of lateral incisor, 1.42 +/- 0.77 mm of canine. Bucco-lingual diameter 3 mm below CEJ was 5.13 +/- 0.37 mm of central incisor, 4.58 +/- 0.46 mm of lateral incisor, and 5.93 +/- 0.47 mm of canine. Buccal bony curvature angle below root apex was 134.7 +/- 17.5degrees at central incisor, 151.0 +/- 13.9degrees at lateral incisor, 153.0 +/- 9.5degrees at canine. Distance between root apex and the deepest point of buccal bony curvature of central incisor was 3.67 +/- 1.28 mm at central incisor, 3.90 +/- 1.51 mm at lateral incisor, and 5.13 +/- 1.70 mm at canine. CONCLUSION: Within the limitation of this study in Korean adults, the thickness of maxillary anterior buccal plate was very thin within 1mm and the thickness of palatal plate was thick, relatively. The buccal bony curvature below root apex of maxillary central incisor was higher than that of lateral incisor and canine and it seems that the buccal bony plate below root apex of central incisor is most curved.
Adult ; Cone-Beam Computed Tomography ; Humans ; Incisor ; Tooth ; Tooth Cervix

Purpose: To report a case of autosomal dominant drusen confirmed by molecular genetic testing and the clinical features and findings of a multimodal diagnostic imaging study.Case summary: A 32-year-old male presented with decreased visual acuity in his right eye from 1 year prior to his first visit. On the first visit, his visual acuities were 0.3 in the right eye and 1.2 in the left eye. A fundus examination showed numerous drusen of various sizes widely distributed on the posterior pole of both eyes, as well as subretinal fibrotic change with pigmentation in the right eye. Optical coherence tomography showed extensive hyperreflective deposits beneath the retinal pigment epithelium in both eyes and small amounts of cystic intraretinal fluid in the right eye. Fluorescein angiography and fundus autofluorescence showed the drusen as multiple hyperfluorescent spots, while indocyanine green angiography indicated hypofluorescence corresponding to the drusen. Genetic sequence analysis revealed a pathogenic variant of the EFEMP1 gene, heterozygous c.1033C>T (p.Arg345Trp), which accords with the diagnosis of autosomal dominant drusen. Intravitreal bevacizumab injection was given in the right eye; however, there was no improvement in the amount of intraretinal fluid nor visual acuity. Conclusions Autosomal dominant drusen is a very rare disease. It is necessary to distinguish it from age-related macular degeneration, as the affected age and clinical features of drusen are different, including the response to anti-vascular endothelial growth factor treatment.

A sensitive and simple liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous quantification of ticagrelor and its active metabolite, AR-C124910XX from 50 µL human plasma using tolbutamide as an internal standard as per regulatory guidelines. Analytes in plasma were extracted by simple protein precipitation using acetonitrile, followed by chromatographic separation with an Acclaim™ RSLC 120 C₁₈ column (2.2 µm, 2.1 × 100 mm) and a gradient acetonitrile-water mobile phase containing 0.1% formic acid within 8 min. Mass spectrometric detection and quantitation were conducted by selected reaction-monitoring on a negative electrospray ionization mode with the following transitions: m/z 521.11 → 361.10, 477.03 → 361.10, and 269.00 → 169.60 for ticagrelor, AR-C124910XX, and tolbutamide, respectively. The lower limit of quantifications was 0.2 ng/mL with linear ranges of 0.2–2,500 ng/mL (r² ≥ 0.9949) for both analytes. All validation data, including selectivity, cross-talk, precision, accuracy, matrix effect, recovery, dilution integrity, stability, and incurred sample reanalysis, were well within acceptable limits. This assay method was validated using K₂-EDTA as the specific anticoagulant. Also, the anticoagulant effect was tested by lithium heparin, sodium heparin, and K₃-EDTA. No relevant anticoagulant effect was observed. This validated method was effectively used in the determination of ticagrelor and its active metabolite, AR-C124910XX, in plasma samples from patients with myocardial infarction.
Heparin ; Humans ; Lithium ; Mass Spectrometry ; Methods ; Myocardial Infarction ; Pharmacokinetics ; Plasma ; Tolbutamide

PURPOSE: "Chest compression-only" CPR encourages CPR by untrained lay people. Guidelines do not include victim's chest exposure, which might result in inaccurate compression point; therefore, this study compares accuracy of lay rescuer's chest compression point in dressed and undressed situations. METHODS: In this prospective observational cross-over study conducted in a simulation center of a tertiary academic hospital in the Republic of Korea, 96 non-medical college student volunteers were asked to point in random order to the location of four reference chest compression points [inter-nipple line (INL), center of the chest (CoC), lower quarter of the sternum (LQS), and lower end of the sternum (LES)]. In dressed and undressed situations, length from sternal notch to each of the subject-recognized compression and reference points and degree of deviation from sternum midline was compared. RESULTS: In both dressed and undressed situations, INL was closest while LQS, CoC, and LES were further away, in said order, from the sternal notch. The undressed situation showed association with lower reference and subjectrecognized chest compression point differences; subjectrecognized chest compression point deviation; and out-ofchest compression point frequency. CONCLUSION: Addition of "exposing victim's chest" to the CPR education program for untrained lay people might facilitate accurate and safe localization of chest compression points in cardiac arrest patients.
Cardiopulmonary Resuscitation* ; Cross-Over Studies ; Education ; Heart Arrest ; Humans ; Prospective Studies ; Republic of Korea ; Sternum ; Thorax* ; Volunteers

PURPOSE: Seizure and syncope are main causes of patient visits to an emergency department (ED). However, differentiating two diseases through history taking and several ancillary tests is difficult in an ED. Some reports have claimed that ammonia or lactate could differentiate between seizure and other medical diseases. Therefore, this study evaluated the ability of ammonia and lactate to differentiate seizure and syncope. METHODS: We reviewed the medical records of 388 patients who visited an ED with seizure or syncope. There were 271 patients in the seizure group (69.8%) and 117 patients in the syncope group (30.2%). Ammonia and lactate levels were compared between the two groups. The optimal level of ammonia and lactate, and their sensitivity and specificity, were evaluated to determine their ability to differentiate seizure and syncope. RESULTS: There were more male in seizure group (66%), but the average age was higher in the syncope group (51+/-21 yrs) (p<0.05). The time interval from symptom to ED was similar between the two groups (seizure group: 213+/-803 min and syncope group: 184+/-512 min, p=0.724). The mean ammonia level in the seizure group was higher than the syncope group (85+/-86 microg/dl and 49+/-29 microg/dl, respectively, p<0.001). The mean lactate level was also higher in the seizure group than the syncope group (3.5+/-2.9 mmol/L and 1.6+/-1.5 mmol/L, respectively, p<0.05). When the cutoff value for ammonia was 50 microg/dL [Area under curve (AUC): 0.617, 95% CI: 0.556-0.678] the sensitivity was 61% and the specificity was 52%. When the cut-off value for lactate was 2 mmol/L [AUC: 0.745, 95% CI: 0.692-0.798] the sensitivity was 60% and the specificity was 76%. CONCLUSION: Serum ammonia or lactate may serve as an ancillary method for differentiating seizure and syncope, but their sole application is unacceptable due to their low sensitivity and specificity.
Ammonia* ; Emergencies ; Humans ; Lactates ; Lactic Acid* ; Male ; Medical Records ; Methods ; Seizures* ; Sensitivity and Specificity ; Syncope*

PURPOSE: Lynch syndrome, the commonest hereditary colorectal cancer syndrome, is caused by germline mutations in mismatch repair (MMR) genes. Three recently developed prediction models for MMR gene mutations based on family history and clinical features (MMRPredict, PREMM1,2,6, and MMRPro) have been validated only in Western countries. In this study, we propose validating these prediction models in the Korean population. MATERIALS AND METHODS: We collected MMR gene analysis data from 188 individuals in the Korean Hereditary Tumor Registry. The probability of gene mutation was calculated using three prediction models, and the overall diagnostic value of each model compared using receiver operator characteristic (ROC) curves and area under the ROC curve (AUC). Quantitative test characteristics were calculated at sensitivities of 90%, 95%, and 98%. RESULTS: Of the individuals analyzed, 101 satisfied Amsterdam criteria II, and 87 were suspected hereditary nonpolyposis colorectal cancer. MMR mutations were identified in 62 of the 188 subjects (33.0%). All three prediction models showed a poor predictive value of AUC (MMRPredict, 0.683; PREMM1,2,6, 0.709; MMRPro, 0.590). Within the range of acceptable sensitivity (> 90%), PREMM1,2,6 demonstrated higher specificity than the other models. CONCLUSION: In the Korean population, overall predictive values of the three models (MMRPredict, PREMM1,2,6, MMRPro) for MMR gene mutations are poor, compared with their performance in Western populations. A new prediction model is therefore required for the Korean population to detect MMR mutation carriers, reflecting ethnic differences in genotype-phenotype associations.
Area Under Curve ; Colorectal Neoplasms ; Colorectal Neoplasms, Hereditary Nonpolyposis ; DNA Mismatch Repair* ; Genetic Association Studies ; Genetic Testing ; Germ-Line Mutation ; Humans ; ROC Curve ; Sensitivity and Specificity