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.

Abuse Potential of Synthetic Cannabinoids: AM-1248, CB-13, and PB-22

Currently, the expanding recreational use of synthetic cannabinoids (SCBs) threatens public health. SCBs produce psychoactive effects similar to those of tetrahydrocannabinol, the main component of cannabis, and additionally induce unexpected pharmacological side effects. SCBs are falsely advertised as legal and safe, but in reality, SCB abuse has been reported to cause acute intoxication and addictive disorders. However, because of the lack of scientific evidence to elucidate their dangerous pharmacological effects, SCBs are weakly regulated and continue to circulate in illegal drug markets. In the present study, the intravenous self-administration (IVSA) paradigm was used to evaluate the abuse potential of three SCBs (AM-1248, CB-13, and PB-22) in rats. All three SCBs maintained IVSA with a large number of infusions and active lever presses, demonstrating their reinforcing effects.The increase of active lever presses was particularly significant during the early IVSA sessions, indicating the reinforcementenhancing effects of the SCBs (AM-1248 and CB-13). The number of inactive lever presses was significantly higher in the SCB groups (AM-1248 and CB-13) than that in the vehicle group, indicating their impulsive effects. In summary, these results demonstrated that SCBs have distinct pharmacological properties and abuse potential.

Abuse Potential of Synthetic Cannabinoids: AM-1248, CB-13, and PB-22

Currently, the expanding recreational use of synthetic cannabinoids (SCBs) threatens public health. SCBs produce psychoactive effects similar to those of tetrahydrocannabinol, the main component of cannabis, and additionally induce unexpected pharmacological side effects. SCBs are falsely advertised as legal and safe, but in reality, SCB abuse has been reported to cause acute intoxication and addictive disorders. However, because of the lack of scientific evidence to elucidate their dangerous pharmacological effects, SCBs are weakly regulated and continue to circulate in illegal drug markets. In the present study, the intravenous self-administration (IVSA) paradigm was used to evaluate the abuse potential of three SCBs (AM-1248, CB-13, and PB-22) in rats. All three SCBs maintained IVSA with a large number of infusions and active lever presses, demonstrating their reinforcing effects.The increase of active lever presses was particularly significant during the early IVSA sessions, indicating the reinforcementenhancing effects of the SCBs (AM-1248 and CB-13). The number of inactive lever presses was significantly higher in the SCB groups (AM-1248 and CB-13) than that in the vehicle group, indicating their impulsive effects. In summary, these results demonstrated that SCBs have distinct pharmacological properties and abuse potential.

The Efficacy and Safety of Platinum/Vinorelbine as More Than Second-Line Chemotherapy for Advanced Non-small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: There is no regimen that is strongly recommended for more than second-line treatment. We investigated the efficacy and safety of platinum/vinorelbine as more than second-line treatment. MATERIALS AND METHODS: We selected patients with advanced non-small cell lung cancer (NSCLC) who received treatment with platinum/vinorelbine at Chungnam National University Hospital from August 2001 to December 2013. The primary end point was the response rate, and secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity. RESULTS: Thirty-five patients were enrolled. Response rate was 22.9% (complete response, 0 patients [0%]; partial response, eight patients [22.9%]; stable disease, 10 patients [28.6%]; progressive disease, 14 patients [40.0%]). A significantly higher response rate was observed for patients who had responded to previous chemotherapy than for those who did not (34.8% [8/23] vs. 0% [0/12], p=0.020). The median PFS was 4 months (range, 1 to 21 months). Patients with adenocarcinoma and non-smokers had a significantly longer PFS than patients with non-adenocarcinoma and smokers (5 months vs. 2 months, p=0.007; 4.5 months vs. 2 months, p=0.046, respectively). The median OS was 10 months (range, 1 to 41 months). Patients with good performance status and non-smokers had a significantly longer OS than patients with poor performance status and smokers (14 months vs. 4 months, p=0.02; 18.5 months vs. 6 months, p=0.049, respectively). The main serious adverse event (grade 3 or 4) was neutropenia (15 events, 13.3%) in a total of 113 cycles. CONCLUSION: Platinum/vinorelbine was effective as more than second-line chemotherapy, and the toxicity was tolerable, in patients with advanced NSCLC.

Efficacy and Tolerability of Valproic Acid Once Daily Dosing for Juvenile Myoclonic Epilepsy

PURPOSE: The purpose of this study was to evaluate the efficacy and tolerability of extended-release valproic acid once daily dosing in juvenile myoclonic epilepsy (JME). METHODS: Medical records of patients who received valproic acid monotherapy for the treatment of JME were retrospectively reviewed. Their clinical information regarding age, gender, seizure types, underlying neurologic status, dosing regimen, response to treatment, and adverse events related to valproic acid, were analyzed. Seizure control, compliance, and adverse events rates were compared between the group of once daily dosing and the group of twice daily dosing. RESULTS: Twenty one patients (11 boys and 10 girls) were included in the study. Twelve patients were taking valproic acid extended-release once daily and nine patients were taking twice a day. More than 50% decrease in myoclonic seizure was achieved in all the patients in both groups. Generalized tonic-clonic seizure was controlled in all the patients who were taking once daily while 3 patients (36%, 3/8 patients) in twice daily group had breakthrough generalized tonic clonic seizures during the 2 year period of treatment. However, there were no statistically significant differences in seizure control, compliance, and adverse event rates between the two groups. CONCLUSION: This study demonstrated that valproic acid extended-release once daily dosing was as effective and tolerable as twice daily in the treatment of JME. Once daily dosing of valproic acid would be convenient which improve patient compliance and consequently bring better outcome in treatment of JME.

Electroencephalographic Features of Rasmussen's Encephalitis by Stage

PURPOSE: The purpose of this study was to describe the characteristic electroencephalographic features in Rasmussen's encephalitis by stage. METHODS: Patients diagnosed with Rasmussen's encephalitis at Seoul National University Children's Hospital were retrospectively assessed. We analyzed the background activities and epileptiform discharges from electroencephalography (EEG) findings to identify the characteristic EEG features by stage. RESULTS: Seven patients were included in the study. The mean age of first seizure onset was 6.7 years, and the mean duration of the prodromal phase was 21.4 months. During disease course, background activities, such as slow waves, were more prominent and diffuse, and contralateral slow waves were observed. In most patients, focal epileptiform discharges were observed during all stages without change. CONCLUSION: As Rasmussen's encephalitis progresses, background abnormalities in the affected hemisphere increased, and contralateral slow waves occurred. However, characteristic EEG findings that were distinguishable at each stage were not observed.

Effectiveness and Tolerability of Fosphenytoin for Pediatric Status Epilepticus

PURPOSE: The study was aimed to investigate the effectiveness and tolerability of intravenous fosphenytoin (fPHT) in the treatment of pediatric status epilepticus (SE). METHODS: Medical-records of patients who received intravenous (IV) fPHT for the treatment of SE were retrospectively reviewed and their clinical data were analyzed regarding age, gender, seizure types, underlying neurologic status, use of other anticonvulsants, loading dose, response and adverse events of IV fPHT. RESULTS: Twenty patients (12 boys and 8 girls) were included in the study. The mean age at administration of IV fPHT was 3.98 years (range 0-18.6 years). Of the 20 patients, 15 patients had no underlying neurological conditions, but five patients were on anticonvulsants. IV fPHT terminated the seizures in 15 of the 20 patients (75%). No adverse events occurred during or after the infusions. CONCLUSION: This study demonstrated that IV fPHT was as effective as phenytoin and was well-tolerated in the treatment of pediatric SE. IV fPHT can be considered as a substitute for phenytoin in the management of pediatric SE.

Efficacy and Tolerability of Rufinamide for Intractable Generalized Epilepsies

PURPOSE: The purpose of the study was to evaluate the efficacy and safety of rufinamide for intractable generalized epilepsies. METHODS: Eighteen patients with intractable generalized epilepsies were included in the study. Their medical records were retrospectively reviewed. Rufinamide was administered as an add-on treatment for intractable epilepsies. The initial administered dose was 10 mg/kg/day, which was subsequently titrated up to 30-50 mg/kg/day. The effectiveness was assessed by comparing the frequency of seizures after the treatment. The difference in number of seizures during 4 weeks was compared before and after reaching the final dose. RESULTS: The study population consisted of 13 males and 5 females (mean age 13.6+/-6.2 years, range 3.3-29.2 years). The responder rate (> or =50% in seizure frequency) was 39% and the seizure free rate was 11%. Retention rate was 44% and the reasons for withdrawal was adverse events (6/18 patients, 33%), aggravation of seizures (4/18 patients, 22%), and ineffectiveness (2/18 patients, 11%). Adverse events included hyperactivity, somnolence, ataxia and polyhidrosis. Adverse events and seizure aggravation occurred even at the starting dose of rufinamide treatment. CONCLUSION: Rufinamide can be used as an efficacious and safe adjunctive anticonvulsant for patients with intractable generalized epilepsy.

A case of Becker muscular dystrophy with early manifestation of cardiomyopathy / 소아과

An 18-year-old boy was admitted with chest discomfort, nausea, and dyspnea at rest. At the age of 3 years, he underwent muscle biopsy and dystrophin gene analysis owing to an enlarged calf muscle and elevated serum kinase level (6,378 U/L) without overt weakness; based on the results, Becker muscular dystrophy (BMD) was diagnosed. The dystrophin gene showed deletion of exons 45 to 49. He remained ambulant and could step upstairs without significant difficulties. A chest roentgenogram showed cardiomegaly (cardiothoracic ratio, 54%), and his electrocardiogram (ECG) showed abnormal ST-T wave, biatrial enlargement, and left ventricular hypertrophy. The 2-dimensional and M-mode ECGs showed a severely dilated left ventricular cavity with diffuse hypokinesis. The systolic indices were reduced, including fractional shortening (9%) and ejection fraction (19%). Despite receiving intensive medical treatment, he died from congestive heart failure 5 months after the initial cardiac symptoms. We report a case of BMD with early-onset dilated cardiomyopathy associated with deletion of exons 45 to 49. Early cardiomyopathy can occur in BMD patients with certain genotypes; therefore, careful follow-up is required even in patients with mild phenotypes of BMD.

Clinical Characteristics of Post-traumatic Seizures in Children

PURPOSE: Post-traumatic seizures (PTS) are well-recognized complications from head injuries and children are particularly more vulnerable to them. The aim of this study was to investigate the clinical characteristics of PTS in children and the findings of several diagnostic tools and to determine the role of prophylactic anticonvulsants. METHODS: We retrospectively reviewed the medical records of patient under 18 years of age who presented with seizures after traumatic brain injuries. Data analyzed included patient's demographics, clinical presentations, radiological and electroencephalographic findings, management and outcomes. RESULTS: Thirty one patients with PTS were included in the study and consisted of 13 males and 18 females. A mean age of the accident was 3.2 years (4 months-6.8 years) and a mean duration of follow-up was 26.0 months (12 months-54 months). Twenty one patients (67.7%) developed seizures within 24 hours after injury. Focal radiological findings were observed in 83.8% and described as subdural or epidural hematoma (25.8%), intraparenchymal hemorrhage (19.3%) and intracerebral parenchymal lesions (51.6%). Electroecephalographic findings included background abnormalities in 32.2% and interictal epileptiform discharges in 45.1%. All patients were treated with anticonvulsants for a certain period of time and a mean duration of treatment was 12.5 weeks (4-40 weeks). Eight patients (25.8%) developed subsequent seizures during follow-up period and 2 patients (6.5%) were diagnosed afterward with post-traumatic epilepsy. CONCLUSION: PTS generally take a benign clinical course, but subsequent seizures including epileptic seizures can occur in minor proportion. In these cases, radiological and electroencephalographic findings are helpful in prediction of clinical course of PTS.

Clinical Implications of Elevated Antiphospholipid Antibodies in Adult Patients with Primary Immune Thrombocytopenia

BACKGROUND/AIMS: Antiphospholipid antibodies (aPL) have been detected in various proportions of patients with primary immune thrombocytopenia (ITP), but the clinical significance of this is debatable. The present study aimed to determine the frequency and clinical implications of elevated aPL in adult patients with ITP. METHODS: We prospectively studied newly diagnosed adult patients with ITP who were enrolled between January 2003 and December 2008 at Chungnam National University Hospital. They were evaluated for the presence of lupus anticoagulant (LA) and anticardiolipin antibodies (aCL) at diagnosis and were followed for the development of thrombosis. RESULTS: Seventy consecutive patients with ITP (median age, 48 years; range, 18 to 79) were enrolled. Twenty patients (28.5%) were positive for aPL at the time of diagnosis: aCL alone in 15 (75%), aCL and LA in two (10%), and LA alone in three (15%). Patients who had platelet counts < 50,000/microL were administered oral prednisolone with or without intravenous immune globulin. No difference was found between the aPL-positive and -negative groups regarding gender, initial platelet count, and response to the therapy. After a median follow-up of 20 months (range, 2 to 68), two of 20 patients who were aPL-positive (10%) developed thrombosis, whereas no thrombotic event was found among those who were aPL-negative. CONCLUSIONS: Our data suggest that aPL levels should be determined at the initial presentation of ITP and that patients found to be aPL-positive should receive closer follow-up for thrombotic events.

Neurologic Complications of Bacterial Meningitis in Children

PURPOSE: This study was performed to investigate clinical findings of acute neurologic complications and risk factors for chronic neurologic complications of bacterial meningitis in children. METHODS: Pediatric patients with community acquired bacterial meningitis diagnosed at Seoul National University Children's Hospital and Bundang Seoul National University Hospital were included. We investigated the relative frequency of neurologic complications and distribution of causative organisms. Chronic neurologic complication was defined as persistent neurologic deficit including recurrent seizures 6 months from the diagnosis. Multiple logistic regression analysis was used to identify risk factors for epilepsy and motor deficits, which were the most frequently reported chronic neurologic complications. RESULTS: A total of 90 cases were included in the study. Thirteen cases with less than 6 months follow-up duration were excluded from the analysis of risk factors for chronic neurologic complications. The mean age at diagnosis was 15.6 months. Streptococcus agalactiae was the most common pathogen accounting for 27 cases, followed by Streptococcus pneumoniae (19 cases), Hemophilus influenzae type b (13 cases), and Neisseria meningitidis (12 cases). Acute neurologic complications were found in 28 cases (31%): cerebral infarction in 16 cases, subdural effusion in 15 cases, and hydrocephalus in 9 cases. Chronic neurologic complications were found in 41 (53%) cases: epilepsy in 28 cases, motor deficit in 16 cases, hearing loss in 6 cases, and cognitive impairment in 4 cases. Cerebral infarction and S. pneumoniae infection were identified as risk factors for epilepsy. Cerebral infarction was a unique risk factor for motor deficit. CONCLUSION: Cerebral infarction is the important risk factor for the development of chronic neurologic complications including epilepsy and motor deficit in pediatric patients with bacterial meningitis.

Neurologic Manifestations and Prognosis in Hemophagocytic Lymphohistiocytosis

PURPOSE: Hemophagocytic lymphohistiocytosis (HLH) presenting with neurologic manifestationhas a poor prognosis due to delayed diagnosis and treatment. We investigated the time between onset of symptoms and diagnosis of HLH and clinical findings and outcome in patients with HLH presenting with neurologic manifestation. METHODS: We retrospectively assessed 24 patients with HLH in Seoul National University Children's Hospital from January 2002 to December 2010. Sex, age on diagnosis, symptoms, laboratory findings, time between onset of symptoms and diagnosis of HLH, cerebral spinal fluid (CSF) findings and brain magnetic resonance imaging (MRI) findings were reviewed. RESULTS: At diagnosis, 7 children (29.2%) had neurologic symptoms, including seizure (n=6) and right side weakness (n=1). Time to diagnosis from onset of symptoms ranged between 7 and 385 days in patients with neurologic symptoms and between 2 and 87 days in patients without neurologic symptoms. Five patients had brain MRI abnormalities; radiologic findings were multiple high signal intensity lesions on T2-weighted image (n=3), focal high signal intensity lesion followed by severe cerebral edema (n=1), and diffuse cerebral atrophy (n=1).Of these 7 patients, 4 died, 1 underwent stem cell transplantation and was followed, 1 was followed after completion of therapy without neurologic sequelae, and 1 is still under treatment and has mild neurologic sequelae. CONCLUSION: HLH presenting with neurologic manifestation is difficult to distinguish from other diseases because of nonspecific symptoms and imaging findings. However, HLH is treatable with chemotherapy and stem cell transplantation, so it is important to consider HLH in a patient with neurologic disease that is unresponsive to treatment and accompanies systemic symptoms.

A Case of Pediatric Nephrolithiasis Associated with Topiramate Treatment

Topiramate is an antiepileptic drug widely used to treat various seizures, mood disorders and migraine based on its various pharmacological mechanisms. Even though nephrolithiasis is listed as one of its side effects, there have been no cases reporting nephrolithiasis caused by use of topiramate on Korean pediatric patients. Since the use of topiramate is increasing in many patients, the possibility of nephrolithiasis after the treatment needs to be considered. Here, we report our experience in correcting neprholithiasis by simply discontinuing topiramate without administering any additional treatments.