• Pediatric Infection and Vaccine
• /
• v.19 no.3
• /
• pp.141-148
• /
• 2012

Purpose : Ventriculoperitoneal (VP) shunt insertion is an important treatment modality in children with hydrocephalus. VP shunt infection is a major complication and an important factor that determines the surgery outcome. This 15-year study was performed to evaluate the epidemiology of VP shunt infections in pediatric patients treated at our center. Methods : A retrospective review of medical records was performed in patients 18 years old or younger who underwent VP shunt insertion surgery from April 1995 to June 2010. Results : Three hundred twenty-seven VP shunt surgeries were performed in a total of 190 pediatric patients (83 females, 107 males). The median age of the patients was 2.4 years (range, 0.02-17.9 years). Having a malignant brain tumor was the most frequent cause for VP shunt insertion. The shunt infection rate was 6.7% (22/327) per 100 operations and 9.5% (18/190) per 100 patients, and the incidence rate was 0.45 infection cases per 100 shunt operations-year. The most common pathogen was coagulase-negative staphylococcus (n=7) followed by methicillin resistant Staphylococcus aureus (n=1). Ten cases were treated with vancomycin and beta-lactam antibiotic (cephalosporin or carbapenem) combination therapy and 7 cases were treated with vancomycin monotherapy. The median duration of antibiotic treatment was 26 days (range, 7 to 58 days). Surgical intervention was performed in 18 cases (18/22, 81.8%). Conclusion : Epidemiologic information regarding VP shunt infections in pediatric patients is valuable that will help guide proper antibiotic management. Additional studies on the risk factors for developing VP shunt infections are also warranted.

• Journal of Korean Neurosurgical Society
• /
• v.30 no.sup1
• /
• pp.79-84
• /
• 2001

To investigate contributory factors of CSF shunt failure, 237 patients, who underwent shunt placement from January 1995 to December 1998 at our hospital, were reviewed retrospectively. The causes of the hydrocephalus were tumor, hemorrhage, infection, congenital anomaly, normal pressure hydrocephalus, trauma and others. One hundred nine revisions of CSF shunting were done during follow up periods. The causes of shunt revisions were mechanical obstruction, malposition, infection and others. The contributory factors of CSF shunt failure and shunt survival rate were analyzed using SPSS. The shunt survival rate at 1, 2 and 3 years after procedure was 77.1%, 75.4%, 74.1% respectively. In the young age group below 10 years old, postinfectous hydrocephalus was the most common high risk factor for shunt revision. In conclusion, the most shunt failures developed in the first year after surgery and the age and causes of the hydrocephalus were major determinant factors of shunt revision.

• Journal of Korean Neurosurgical Society
• /
• v.64 no.2
• /
• pp.297-308
• /
• 2021

Objective : Shunt infection is a common complication while treating hydrocephalus. The antibiotic-impregnated shunt catheter (AISC) was designed to reduce shunt infection rate. A meta-analysis was conducted to study the effectiveness of AISCs in reduction of shunt infection in terms of age, follow-up time and high-risk patient population. Methods : This study reviewed literature from three databases including PubMed, EMBASE, and Cochrane Library (from 2000 to March 2019). Clinical studies from controlled trials for shunt operation were included in this analysis. A subgroup analysis was performed based on the patient's age, follow-up time and high-risk population. The fixed effect in RevMan 5.3 software (Cochrane Collaboration) was used for this meta-analysis. Results : This study included 19 controlled clinical trials including 10105 operations. The analysis demonstrated that AISC could reduce the infection rate in shunt surgery compared to standard shunt catheter (non-AISC) from 8.13% to 4.09% (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.40-0.58; p=0.01; I2=46%). Subgroup analysis of different age groups showed that AISC had significant antimicrobial effects in all three groups (adult, infant, and adolescent). Follow-up time analysis showed that AISC was effective in preventing early shunt infections (within 6 months after implant). AISC is more effective in high-risk population (OR, 0.24;95% CI, 0.14-0.40; p=0.60; I2=0%) than in general patient population. Conclusion : The results of meta-analysis indicated that AISC is an effective method for reducing shunt infection. We recommend that AISC should be considered for use in infants and high-risk groups. For adult patients, the choice for AISC could be determined based on the treatment cost.

• Proceedings of the KIPE Conference
• /
• 2011.11a
• /
• pp.235-236
• /
• 2011

본 논문에서는 세 개의 Shunt 저항을 이용하여 3상 인버터의 상전류를 검출하였다. Shunt 저항을 이용할 경우 전류 검출이 불가능한 제한 영역이 발생한다. 이러한 제한영역을 보상하기 위해 제한영역에 대하여 분석하였으며, 제한 영역은 추가적인 전류 추정방법을 이용하여 보상하였다. 이를 시뮬레이션을 통하여 검증하였다.

• Proceedings of the KIPE Conference
• /
• 2011.07a
• /
• pp.200-201
• /
• 2011

본 논문에서는, 동기 전동기 구동을 위해 세 개의 Shunt Resistor를 이용하여 전류를 피드백 받는 방법에 대하여 분석한다. 특히 세 개의 Shunt Resistor를 이용하여 전류를 피드백 받는 경우 인버터 출력 전압의 크기에 따라 피드백 받은 상전류 정보의 왜곡이 발생하는 문제점에 대하여 분석하고 이를 해결하기 위한 새로운 방법을 제안하며, 실험 결과를 통하여 검증한다.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2003.02a
• /
• pp.143-145
• /
• 2003

External shunt resistor is used in Nb/AlOx/Nb Josephson junction which is basic component of RSFQ circuit. This is to increase damping and to make the so called 'self-reset' optimized for high speed operation. In this study, we fabricated and investigated sheet resistance of Pd and PdAu thin film, and simulated the inductance effect of the shunt resistor to the Josepshon junction dynamics.

• Advances in pediatric surgery
• /
• v.16 no.2
• /
• pp.196-202
• /
• 2010

Abdominal cerebrospinal fluid pseudocyst is an uncommon complication of ventriculoperitoneal shunt (VPS) performed for hydrocephalus. The incidence of VPS complications in children is higher than in adults. There are controversies and difficulties in the treatment of the abdominal pseudocyst. We report a case of abdominal pseudocyst complicating VPS in a boy. Partial excision of pseudocyst and replacement of the VP shunt were effective during a followup of 18 months postoperatively with no recurrence.

• Journal of Korean Neurosurgical Society
• /
• v.41 no.6
• /
• pp.429-431
• /
• 2007

Although the ventriculo-peritoneal shunt is the treatment of choice when hydrocephalus should be corrected, the ventriculo-atrial shunt still holds strong alternative when the peritonium is precluded due to the several reasons. During the ventriculo-atrial shunt operation, it is not always easy to dissect and find the corresponding venous structures. In this technical note, the author describes a simple method of percutaneous insertion for placement of the atrial end.

• Journal of Korean Neurosurgical Society
• /
• v.49 no.4
• /
• pp.217-221
• /
• 2011

Objective : This paper presents data from a retrospective study of endoscopic third ventriculostomy (ETV) in patients with shunt malfunction and proposes a simple and reasonable post-operative protocol that can detect ETV failure. Methods : We enrolled 19 consecutive hydrocephalus patients (11 male and 8 female) who were treated with ETV between April 2001 and July 2010 after failure of previously placed shunts. We evaluated for correlations between the success rate of ETV and the following parameters : age at the time of surgery, etiology of hydrocephalus, number of shunt revisions, interval between the initial diagnosis of hydrocephalus or the last shunt placement and ETV, and the indwelling time of external ventricular drainage. Results : At the time of ETV after shunt failure, 14 of the 19 patients were in the pediatric age group and 5 were adults, with ages ranging from 14 months to 42 years (median age, 12 years). The patients had initially been diagnosed with hydrocephalus between the ages of 1 month 24 days and 32 years (median age, 6 years 3 months). The etiology of hydrocephalus was neoplasm in 7 patients; infection in 5; malformation, such as aqueductal stenosis or megacisterna magna in 3; trauma in 1; and unknown in 3. The overall success rate during the median follow-up duration of 1.4 years (9 days to 8.7 years) after secondary ETV was 68.4%. None of the possible contributing factors for successful ETV, including age (p=0.97) and the etiology of hydrocephalus (p=0.79), were statistically correlated with outcomes in our series. Conclusion: The use of ETV in patients with shunt malfunction resulted in shunt independence in 68.4% of cases. Age, etiology of hydrocephalus, and other contributing factors were not statistically correlated with ETV success. External ventricular drainage management during the immediate post-ETV period is a good means of detecting ETV failure.

• Journal of Korean Neurosurgical Society
• /
• v.52 no.4
• /
• pp.320-324
• /
• 2012

Objective : The purposes of this study are to investigate the factors that may be related to ventriculoperitoneal (VP) shunt in patients with cerebellar hematoma and the effect of severe fourth ventricular hemorrhage, causing obstructive hydrocephalus on subsequent VP shunt performance. Methods : This study included 31 patients with spontaneous cerebellar hematoma and concomitant fourth ventricular hemorrhage, who did not undergo a surgical evacuation of hematoma. We divided this population into two groups; the VP shunt group, and the non-VP shunt group. The demographic data, radiologic findings, and clinical factors were compared in each group. The location of the hematoma (whether occupying the cerebellar hemisphere or the vermis) and the degree of the fourth ventricular obstruction were graded respectively. The intraventricular hemorrhage (IVH) score was used to assess the IVH severity. Results : Ten out of 31 patients underwent VP shunt operations. The midline location of cerebellar hematoma, the grade of fourth ventricle obstruction, and IVH severity were significantly correlated with that of VP shunt operation (p=0.015, p=0.013, p=0.028). The significant variables into a logistic regression multivariate model resulted in statistical significance for the location of cerebellar hemorrhage [p=0.05; odds ratio (OR), 8.18; 95% confidence interval (CI), 1.00 to 67.0], the grade of fourth ventricle obstruction (p=0.044; OR, 19.26; 95% CI, 1.07 to 346.6). Conclusion : The location of the cerebellar hematoma on CT scans and the degree of fourth ventricle obstruction by IVH were useful signs for the selection of VP shunt operation in patients with spontaneous cerebellar hematoma and concomitant acute hydrocephalus.