Predictors of ventriculoperitoneal shunt pathology.

BACKGROUND: Diagnosis of ventriculoperitoneal (VP) shunt pathology remains a dilemma in patients with nonspecific constitutional signs and symptoms. Eosinophilia has been described in association with shunt infection and malfunction. Our purpose was to further define the relationship of eosinophilia and shunt pathology and to determine other predictors of VP shunt infection and malfunction. METHODS: Records of all patients admitted with a suspected VP shunt infection or malfunction were reviewed. The following data were abstracted: age; reason for and age at initial shunt placement; number of revisions; date of last revision; history of fever or vomiting; ventricular fluid cell count; differential and culture; complete blood count and differential; need for shunt revision or replacement; and use of antibiotics. After exclusion of patients admitted for initial shunt placement, the remainder were divided into three groups: those with shunt infection; those with shunt malfunction; and those without documented infection or malfunction. RESULTS: Of 12 patients with shunt infection and 69 with shunt malfunction, 2 and 11, respectively, had eosinophilia defined as > or =5%. The presence of eosinophilia had a 96% positive predictive value for shunt pathology and raised the pretest probability of pathology from 84% to a post test probability of 96%. The combination of fever history and ventricular fluid neutrophils >10% had a 99% specificity for shunt infection, had a 93 and 95% positive and negative predictive value, respectively, and raised the pretest probability of infection from 12% to a posttest probability of 92%. CONCLUSIONS: In patients suspected of having a VP shunt malfunction, the presence of > or =5% eosinophils in the ventricular fluid indicates shunt pathology. The combination of fever and ventricular fluid neutrophils > 10% is predictive of shunt infection.     

Neuroimaging of ventriculoperitoneal shunt complications in children

The ventriculoperitoneal shunt is the mainstay of treatment for hydrocephalus. Despite its widespread use and safety record, it often malfunctions due to complications such as obstruction, breakage, migration and infection. This necessitates a systematic approach to diagnosing the etiology of shunt failure. Any evaluation should begin with an appraisal of the patient's symptoms. In acute malfunction, nausea, vomiting, irritability, seizures, headache, lethargy, coma and stupor are seen. In chronic malfunction, neuropsychological signs, feeding pattern changes, developmental delay, decline in school performance, headaches and increased head size are often seen. The next step in evaluation is a CT scan of the head to evaluate ventricular size. Prior imaging studies should be obtained for comparison; if the ventricles have enlarged over time, shunt malfunction is likely. If there is no such increase or dilation in the first place, other diagnoses are possible. However, "slit ventricle syndrome" should also be considered. When prior imaging is not available, pumping the reservoir, a radionuclide shuntogram, a shunt tap or even surgical exploration are options. The goals of this paper are to provide an algorithm for evaluating shunt malfunction and to illustrate the radiographic findings associated with shunt failure.     

Disconnection as a cause of ventriculoperitoneal shunt malfunction in multicomponent shunt systems

The cause of malfunction in 275 consecutive ventriculoperitoneal (VP) shunt revisions over an 8-year period were retrospectively analyzed. In all cases the shunt revised was a multicomponent (Holter) VP shunt. Disconnections in the system accounted for 41 (15%) of the malfunctions. The more distal the connection was from the ventricle, the higher the likelihood of disconnection. Furthermore, occipitally placed shunts had a significantly higher tendency to dislocate than frontally placed shunts.     

脑室腹腔分流术后分流管阻塞的诊断和处理

目的 探讨脑积水脑室腹腔分流术后分流管阻塞的诊断和处理.方法 收集1977年-2007年由同济医院神经外科治疗的脑积水127例(儿童29例,婴幼儿98例),其中40例出现分流功能障碍行矫正手术.研究发现脑脊液分流障碍的早期表现是脑脊液分流隧道聚积,少数病例有分流感染,分流导管堵塞来自脉络丛,其他常见异物(棉花纤维、毛发、炎性肉芽组织等)围绕脑室与腹腔导管的末端.防止分流管阻塞的措施包括:① 选择最佳脑室导管;②预防感染;③手术薄膜覆盖皮肤,避免与分流导管接触;④改善移植材料的生物相容性.结论 随访5~10年,除2例髓母细胞瘤并发脑积水死亡外,其余38例长期存活.结论 脑室腹腔分流术后功能障碍应及时矫正处理.

Abstract：

Objective To explore the diagnosis and treatment of ventriculoperitoneal shunt blockage.Methods Retrospective study was conducted in 127 patients with hydrocephalus(29 children and 98 infants) referred to Department of Neurosurgery between 1977 and 2007,40 of them received surgery for shunt malfunction.Referral pattern,presenting symptoms and signs,results of computed tomography(CT) scanning,operative findings,and clinical outcomes were recorded.ResultsThe early manifestations of shunt dysfunction included: accumulation of cerebrospinal fluid diversion tunnels,shunt infections,shunt catheter blockage from the choroid plexus,and foreign body(cotton fiber,hair,inflammatory granulation tissue,etc.).The measures for preventing the shunt blockage included: optimal ventricle catheter,prevention of infection,avoiding contact with the shunt catheter by surgical film,and improving the graft material biocompatibility.During a follow-up period of 5-10 years,two cases with medulloblastoma cell tumor died,the other cases achieved long-term survival.Conclusions The shunt dysfunction should be managed properly to get excellent long-term results.     

Intraabdominal metastasis of cerebellar medulloblastoma through ventriculoperitoneal shunt

We present a 6-year-old girl with cerebellar medulloblastoma causing obstructive hydrocephalus that was treated by ventriculoperitoneal shunting. The patient subsequently underwent surgical excision of the tumor followed by adjuvant craniospinal radiotherapy. Nine months after shunting, multiple intraabdominal metastatic lesions were found. Although the risk is low, ventriculoperitoneal shunting may facilitate the spread of malignant cells.     

Hydrothorax: transdiaphragmatic migration of a ventriculoperitoneal shunt catheter

Symptomatic hydrothorax following ventriculoperitoneal shunt insertion is a very rare complication. The patient was a 5-month-old child known to have had shunted congenital hydrocephalus two months before. He presented to the emergency room in respiratory distress. Chest X-ray and computerized tomography images confirmed left hydrothorax and showed transdiaphragmatic migration of the tip of the peritoneal catheter to the thoracic cavity. After the catheter had been shortened and replaced to the peritoneal cavity, the patient's symptoms abated.     

An unusual complication of tapping a ventriculoperitoneal shunt.

A case is reported describing a complication of an unsuccessful attempt to aspirate the reservoir of a ventriculoperitoneal shunt system with a suspected shunt infection. This arose due to a misunderstanding of the anatomy of the shunt and resulted in an intracerebral haematoma. The complications of cerebrospinal fluid shunting and the difficulty in the diagnosis thereof are outlined. We discuss the role and method of shunt tapping in diagnosing shunt problems before reviewing the literature describing the rationale. The variation in shunt design is emphasized. Guidelines are then proposed not to dissuade physicians from tapping shunts but to ensure that the procedure is performed safely and in collaboration with neurosurgical units.     

Syndrome of overdrainage associated with disconnection of a ventriculoperitoneal shunt

We present the case of a child who developed the syndrome of cerebrospinal fluid (CSF) overdrainage with slit-like ventricles on CT in the setting of a disconnected distal shunt valve. Upgrading the shunt alleviated his symptoms. It is suggested that the presence of a patent fibrous tract allowed the overdrainage of CSF.