An artificial neural-network approach to identify motor hotspot for upper-limb based on electroencephalography: a proof-of-concept study

Abstract Background To apply transcranial electrical stimulation (tES) to the motor cortex, motor hotspots are generally identified using motor evoked potentials by transcranial magnetic stimulation (TMS). The objective of this study is to validate the feasibility of a novel electroencephalography (EEG)-based motor-hotspot-identification approach using a machine learning technique as a potential alternative to TMS. Methods EEG data were measured using 63 channels from thirty subjects as they performed a simple finger tapping task. Power spectral densities of the EEG data were extracted from six frequency bands (delta, theta, alpha, beta, gamma, and full) and were independently used to train and test an artificial neural network for motor hotspot identification. The 3D coordinate information of individual motor hotspots identified by TMS were quantitatively compared with those estimated by our EEG-based motor-hotspot-identification approach to assess its feasibility. Results The minimum mean error distance between the motor hotspot locations identified by TMS and our proposed motor-hotspot-identification approach was 0.22 ± 0.03cm, demonstrating the proof-of-concept of our proposed EEG-based approach. A mean error distance of 1.32 ± 0.15cm was measured when using only nine channels attached to the middle of the motor cortex, showing the possibility of practically using the proposed motor-hotspot-identification approach based on a relatively small number of EEG channels. Conclusion We demonstrated the feasibility of our novel EEG-based motor-hotspot-identification method. It is expected that our approach can be used as an alternative to TMS for motor hotspot identification. In particular, its usability would significantly increase when using a recently developed portable tES device integrated with an EEG device

The First Successful Transapical Aortic Valve Implant in Korea

Transcatheter aortic valve implantation is an alternative to open heart surgery in high risk patients with severe aortic stenosis. High mortality and complications related to cardiopulmonary bypass for conventional open heart surgery can be avoided with this new less invasive technique. In case of concomitant severe arterial disease, the transapical approach is recommended rather than transfemoral access. An 80-yr-old man with symptomatic aortic stenosis and who had very high surgical risk factors such as diabetes mellitus, hypertension, a history of stroke, bronchial asthma including poor pulmonary function and hepatocellular carcinoma was treated with a transapical aortic valve replacement. The expected mortality in this patient was 25.4% by Euroscore if we performed the conventional aortic valve surgery. The patient was discharged and was well at the 45 follow-up days. We report the first case of successful transcatheter transapical aortic valve implantation which is available recently in Korea

Repair of Long-segment Congenital Tracheal Stenosis

Long-segment tracheal stenosis in infants and small children is difficult to manage and can be life-threatening. A retrospective review of 12 patients who underwent surgery for congenital tracheal stenosis between 1996 and 2004 was conducted. The patients' median age was 3.6 months. All patients had diffuse tracheal stenosis involving 40-61% (median, 50%) of the length of the trachea, which was suspected to be associated with complete tracheal ring. Five patients had proximal bronchial stenosis also. Ten patients had associated cardiac anomalies. Three different techniques were performed; pericardial patch tracheoplasty (n=4), tracheal autograft tracheoplasty (n=6), and slide tracheoplasty (n=2). After pericardial tracheoplasty, there were 2 early and 2 late deaths. All patients survived after autograft and slide tracheoplasty except one who died of pneumonia one year after the autograft tracheoplasty. The duration of ventilator support was 6-40 days after autograft and 6-7 days after slide tracheoplasty. The duration of hospital stay was 13-266 days after autograft and 19-21 days after slide tracheoplasty. Repeated bronchoscopic examinations were required after pericardial and autograft tracheoplasty. These data demonstrate that pericardial patch tracheoplasty show poor results, whereas autograft or slide tracheoplasty gives excellent short- and long-term results

Pure Basaloid Squamous Cell Carcinoma of the Uterine Cervix: A Case Report

Basaloid squamous cell carcinoma of the uterine cervix is an extremely rare malignancy of the female genital tract with a poorer clinical outcome than squamous cell carcinoma of the uterine cervix. We report a case of pure basaloid squamous cell carcinoma of the uterine cervix. A 70-yr-old woman with vaginal bleeding was referred to our institute. A basaloid squamous cell carcinoma of the uterine cervix, of International Federation of Gynecology and Obstetrics (FIGO) stage Ib1, was diagnosed by a loop electrosurgical excision procedure cone biopsy. A radical hysterectomy was performed, along with bilateral salpingo-oophorectomy, pelvic lymph node dissection, and para-aortic lymph node sampling. Pathologic findings were consistent with a basaloid squamous cell carcinoma confined to the cervix without an extracervical tumor. No further treatment was administered and there was no clinical evidence of recurrence during the 12 months of follow-up. Follow-up for the patient is ongoing. Although basaloid squamous cell carcinoma of the uterine cervix is thought to behave aggressively, accumulation of data on these rare tumors is necessary to determine whether their behavior differs significantly from that of conventional cervical squamous cell carcinoma of similar clinical stage. These data would be useful for defining the best diagnosis and treatment for these rare tumors

Urachal Anomalies in Children: A Single Center Experience

The objective of this study is to define optimal diagnosis and treatment strategies for patients with urachal anomalies in the pediatric age group. The medical records of 21 children who had undergone surgery for urachal anomalies at Severance Hospital, Yonsei University College of Medicine from January 1990 to April 2005 were reviewed. The subjects included 14 males and 7 females (M:F 2:1). The four types of urachal anomalies confirmed were a urachal cyst in 10 patients (47.6%), a patent urachus in 6 (28.6%), a urachal sinus in 4 (19.0%) and a urachal diverticulum in 1 (4.8%) patient. The most common presenting complaint was umbilical discharge (n = 10, 40.0%), followed by abdominal mass (n = 9, 36.0%). Urachal anomalies were diagnosed by ultrasonography in 18 patients, and 7 of them were additionally examined by computed tomography. The remaining patients were diagnosed solely by surgical exploration. Excision was performed in all patients and was supplemented by partial cystectomy in three. Umbilical discharge was the most common clinical manifestation in our patients, suggesting that ultrasonography should be performed in patients with umbilical discharge to differentiate urachal anomalies. We found the most common anomaly to be the urachal cyst, and all patients were successfully treated by surgical excision

Thrombocytopenia represents a risk for deterioration of liver function after radiofrequency ablation in patients with hepatocellular carcinoma

Background/AimsWe evaluated changes in liver function parameters and risk factors for the deterioration of liver function 12 months after percutaneous radiofrequency ablation (RFA) therapy in patients with hepatocellular carcinoma (HCC).MethodsThe subjects in this retrospective study comprised 102 patients with HCC who had undergone RFA therapy and exhibited no recurrence of HCC 12 months thereafter. Serial changes in serum total bilirubin and albumin, prothrombin time, and Child-Pugh score were evaluated before RFA and 3, 6, 9, and 12 months thereafter. Deterioration of liver function was defined when the Child-Pugh score increased by at least 2 at 12 months after RFA therapy. We determined the factors related to aggravation of liver function after RFA therapy.ResultsLiver function had deteriorated 12 months after RFA in 29 patients (28.4%). Serum albumin levels decreased significantly from before (3.7±0.1 g/dL, mean±SD) to 12 months after RFA therapy (3.3±0.1 g/dL, P=0.002). The Child-Pugh score increased significantly during the same time period (from 6.1±0.2 to 7.2±0.3, P<0.001). Pre-RFA thrombocytopenia (≤100,000/mm3) was revealed as a significant risk factor for the deterioration of liver function after RFA. However, no patients had episodes of bleeding as a complication of RFA.ConclusionsAmong the liver-function parameters, serum albumin level was markedly decreased in HCC patients over the course of 24 months after RFA therapy. A pre-RFA thrombocytopenia represents a major risk factor for the deterioration of liver function

Survival outcomes of hepatic resection compared with transarterial chemoembolization or sorafenib for hepatocellular carcinoma with portal vein tumor thrombosis

Background/Aims:Treating hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT) remains controversial. We compared the outcomes of hepatic resection (HR), transarterial chemoembolization (TACE), and sorafenib therapy as treatments for HCC with PVTT. Methods:Patients diagnosed as HCC with PVTT between January 2000 and December 2011 who received treatment with sorafenib, HR, or TACE were included. Patients with main PVTT, superior mesenteric vein tumor thrombosis, or Child-Turcotte-Pugh (CTP) class C were excluded. The records of 172 patients were analyzed retrospectively. HR, TACE, and sorafenib treatment were performed is 40, 80, and 52 patients respectively. PVTT was classified as either involving the segmental branch (type I) or extending to involve the right or left portal vein (type II). Results:The median survival time was significantly longer in the HR group (19.9 months) than in the TACE and sorafenib groups (6.6 and 6.2 months, respectively; both p<0.001), and did not differ significantly between the latter two groups (p=0.698). Among patients with CTP class A, type I PVTT or unilobar-involved HCC, the median survival time was longer in the HR group than in the TACE and sorafenib groups (p=0.006). In univariate analyses, the initial treatment method, tumor size, PVTT type, involved lobe, CTP class, and presence of cirrhosis or ascites were correlated with overall survival. The significant prognostic factors for overall survival in Cox proportional-hazards regression analysis were initial treatment method (HR vs. TACE: hazard ratio=1.750, p=0.036; HR vs. sorafenib: hazard ratio=2.262, p=0.006), involved lobe (hazard ratio=1.705, p=0.008), PVTT type (hazard ratio=1.617, p=0.013), and CTP class (hazard ratio=1.712, p=0.012). Conclusions:Compared with TACE or sorafenib, HR may prolong the survival of patients with HCC in cases of CTP class A, type I PVTT or unilobar-involved HCC