Dental Age Estimation Using the Demirjian Method: Statistical Analysis Using Neural Networks / 대한법의학회지

In children and adolescents, dental age estimation is performed with the development of the teeth. Various statistical analysis methods have been used to determine the relationship between age and dental maturity and develop an accurate method of age calculation. This study attempted to apply a neural network model for the statistical analysis of dental age estimation in children and evaluated its applicability. This study used 1196 panoramic radiographs of patients aged 3–16 years, and 996 and 200 were randomly classified into training and test sets, respectively. The dental maturity of the mandibular left teeth was evaluated using Demirjian's method, the neural network model using the backpropagation algorithm was derived using training sets, and the errors were evaluated using 100 radiographs of each male and female as test sets. In addition, multiple linear regression analysis was conducted on the same training set, and the error was calculated by applying it to the test set and comparing it with the error of the neural network model. In the neural network model, the mean absolute error (MAE) and root mean squared error (RMSE) were 0.589 and 0.783 in male subjects and 0.529 and 0.760 in female subjects, respectively. In the multiple linear regression model, the MAE and RMSE were 0.600 and 0.748 in male subjects and 0.566 and 0.789 in female subjects, respectively. When applying the neural network model to the statistical analysis of the dental developmental stage, the results were as accurate as those of conventional statistical analysis methods. This study’s approach is expected to be useful for estimating the ages of children.

Molecular and Morphological Characteristics of a New Species Collected from an Insect (Cicindela transbaicalica) in Korea

To exploit insect-derived fungi, insects were collected from seven different regions in Korea, including Gyeongbuk, Goryeong, and several fungi were isolated from them. A fungal strain designated 21-64-D was isolated from riparian tiger beetle (Cicindela transbaicalica) and morphologically identified as a species belonging to the genus Oidiodendron. Phylogenetic analysis using the nucleotide sequences of internal transcribed spacer (ITS) regions and the partial sequence of the large subunit of the nuclear ribosomal RNA (LSU) gene revealed the distinct phylogenetic position of the isolate among recognized Oidiodendron species including its closest neighbors O. chlamydosporicum, O. citrinum, O. maius, and O. pilicola. The hyphal and conidial morphology of the strain, particularly club-shaped hyphae, clearly differentiated it from its close relatives. Results indicated that 21-64-D is a novel species in the genus Oidiodendron, for which the name Oidiodendron clavatum sp. nov. is proposed.

A Case of Unilateral Internal Carotid Artery Stenosis Presenting with Chronic Isolated Dizziness / 대한평형의학회지

It is customary that the dizziness related to cerebral perfusion might be caused by insufficient posterior circulation. The occurrence and nature of dizziness originating from anterior circulation has not been well-known. Here, we report a chronic dizzy woman presenting with severe internal carotid artery stenosis, which improved after carotid artery stenting.

Isolated Tongue Paralysis as Presentation of Seropositive Neuromyelitis Optica Spectrum Disorder

Neuromyelitis optica spectrum disorder (NMOSD) is characterized by a characteristic clinical presentation or positivity for the anti-aquaporin-4 antibody. Lesions involving the dorsal medulla are typical of NMOSD, but isolated tongue paralysis has not been reported previously. We report a rare case of NMOSD presenting with isolated tongue paralysis and swelling due to intrinsic tongue muscle paralysis, which was caused by bilateral involvement of the hypoglossal nuclei in the lower dorsal medulla oblongata.

Congenital Bladder Diverticulum in a Child with Recurrent Urinary Tract Infection / 대한비뇨기과학회지

Congenital bladder diverticula, unassociated with an obstruction or a neuropathic bladder, are unusual, occurring almost exclusively in boys. Most congenital bladder diverticula are silent, usually developing from a primary defect due to localized weakness in the detrusor. We report a case of congenital bladder diverticulum in a 5-year-old boy with a history of recurrent urinary tract infection.

A Case of Primary Carcinoid Tumor of the Urinary Bladder / 대한비뇨기과학회지

Primary carcinoid tumor of the urinary bladder is extremely rare. We report a case of primary carcinoid tumor of the urinary bladder in a 45-year-old man who presented with frequency, dysuria and urinary tenesmus for 6 months with clinicopathologic, immunohistochemical and ultrastructural findings.

A Case of Spontaneous Rupture of the Autosomal Dominant Polycystic Kidney associated with Ureteral Calculi / 대한비뇨기과학회지

Spontaneous rupture of the kidney is a relatively uncommon disease. It occurs secondary to various kinds of underlying disease such as infection, hydronephrosis, calculous disease, benign or malignant tumor, renal artery aneurysm and arteriosclerosis. Recently we experienced a case of spontaneous rupture of the adult polycystic kidney with ureteral calculi in 45 years old male.

Ureterolithotomy Using Laparoscopy Assisted Small Incision in Upper Ureter Stone / 대한비뇨기과학회지

PURPOSE: Most stones in the urinary tract can be managed by SWL, percutaneous nephrolithotomy and ureteroscopic lithotripsy, however in some patients whose calculi were not managed by these methods, open surgery must be considered. We performed ureterolithotomy using laparoscopy assisted small incision in upper ureter stone and compared their efficacy with conventional ureterolithotomy. MATERIALS AND METHODS: 10 patients whose stones were not fragmented by SWL or who showed intractable pain were managed by laparoscopy assisted small flank incision of 5cm without insufflation of gas(group I). We compared the efficacy of this procedure with 10 patients who underwent conventional ureterolithotomy(group II) in operating time, the number of analgesics required for the management of postoperative pain control, hospital stay, immediate complication and medical expenses. RESULTS: The stones were successfully removed in all patients. The operating times ranged 40 to 150 min(mean 98.5) in group I and 60 to 190 min(mean 83.0) in group II. The mean requirement of analgesics and hospital stay after surgery were 2.4 times and 3.4 days in group I, and 8.4 times and 6.8 days in group II respectively. The mean medical expenses were 803,000 won in group I and 956,000 won in group II. No intra-operative complication was noted in group II, but 1 patient showed urine leakage in group I, which was managed by placement of ureteral catheter. In immediate postoperative complications, 1 patient complained wound pain persisted over 1 month in group I but 6 patients in group II. CONCLUSIONS: Ureterolithotomy using laparoscopy assisted small incision is another modality in the management of upper ureter stone which was not managed by SWL, percutaneous nephrolithotomy and ureteroscopic lithotripsy. Furthermore, this procedure is safe and effective, and offers significant advantages in hospital stay, requirement of analgesics, and medical expense.