Importance of anti-siphon devices in the treatment of pediatric hydrocephalus

The effects of an antisiphon device (ASD) on shunt flow and intracranial pressure (ICP) in 16 children with hypertensive hydrocephalus were examined using quantitative radionuclide shuntography (^99mTc) with the children in supine and sitting positions. The average age of these patients was 9.5 years. Results were compared with those recorded in 36 patients with adult normal-pressure hydrocephalus (NPH). The closing pressure levels of shunt valve used were low in 8 cases, medium in 7 and high in 1. Half the children (8) had shunt systems with, and the other 8 without, ASD. In the children who had the shunt system without ASD, sitting shunt flow was significantly greater than supine shunt flow, which indicated overdrainage. Conversely, in children who had the shunt system with ASD, supine shunt flow was greater than sitting shunt flow. Because ASD prevented overdrainage, ICP was higher with the shunt system with ASD than with the shunt system without ASD. Without ASD, sitting shunt flow of children was lower than that of adult patients with NPH because of the lower hydrostatic pressure, which correlated with their height. Conversely, in the presence of a shunt system with ASD, sitting shunt flow of children was greater than that of adults, because of the higher ICP and lower hydrostatic pressure. The effect of ASD was smaller in children than in adults, because positive pressure over the ASD was greater (hypertension vs normal pressure) and negative pressure under the ASD was less (short vs tall) in children than in adults. Thus, in children the ASD was effective in preventing overdrainage. An overfunction of the ASD, which has sometimes been observed in adult patients with NPH, was not encountered. The relationships among the function of the ASD and ICP, height and position of the ASD are discussed.Presented at the Consensus Conference: Hydrocephalus '92, Assisi, Italy, 26–30 April 1992     

Reducing the incidence of infection in pediatric cerebrospinal fluid shunt operations

We reviewed our experience with shunt implantation during two time periods. From June 1985 to December 1990, 201 children with hydrocephalus underwent 382 operations. Among these children 36 (18%) developed a proven shunt infection, with an incidence rate per procedure of 9.4%. As a result of this study, a new effective protocol for shunt procedures involving modifications to the perioperative (antibiotic prophylaxis) and intraoperative management (meticulous surgical technique, complete shunt revision) of children undergoing initial shunt implantation or revision was initiated. With this new protocol 75 children underwent a total of 112 procedures between January 1991 and December 1995. The incidence of shunt infection decreased, with a per patient rate of 8% and a per procedure rate of 5.3%. The majority of infections in our study were caused by Staphylococcus epidermidis, which was found in 22 (52.3%) patients.     

Cerebrospinal fluid shunt infections in infants

Infection remains a major cause of morbidity and mortality following CSF shunt procedures. In this study 191 shunt procedures carried out from January 1981 to December 1992 in a series of 81 infants (less than 6 months old) were retrospectively analyzed for possible risk factors. The overall surgical infection rate was 7.8%, with 15 infections occurring in 14 patients (17.2%). No significant difference in the rate of infections was found in relation to sex, birth weight, gestational age, and type of shunt procedure (primary insertion/revision). The occurrence of other infections during the period of shunt surgery did not influence the infection risk either. Intraventricular hemorrhage and central nervous system infections as causes of the hydrocephalus were found to correlate with septic risk. Young age (less than 6 months) seems to represent the main risk factor, and this is related both to the immunologic deficiency and to the particular features of residential bacterial flora in this age group.     

An unusual ventriculoperitoneal shunt complication: spontaneous knot formation

This article aims to describe an extraordinary complication of a ventriculoperitoneal shunt system that formed a knot spontaneously and lead to a shunt malfunction. A 3-year-old male patient was operated due to posttraumatic hydrocephalus. After an uneventful follow-up period of 34 months, he presented with shunt malfunction. During the shunt revision surgery, the peritoneal catheter was found to form a loop over itself. There are various complications of ventriculoperitoneal shunt systems. Migration to body cavities is among the most interesting ones. This is the fifth report describing this rare complication. Hydrocephalic patients should be closely followed up after shunt surgery for various extraordinary complications.     

Reflex sympathetic dystrophy induced by shunt malfunction: a case report]

A 60-year-old male presented with normal pressure hydrocephalus following subarachnoid hemorrhage and underwent a shunt operation. However, a shunt effective range was so narrow that he repeated a sign of overdrainage and underdrainage of CSF. At the result, reflex sympathetic dystrophy (RSD) as a complication of overdrainage was demonstrated. We could prescribe appropriate shunt flow rate by using siphon control system instead of antisiphon device (ASD) and then avoid shunt malfunction. In addition, medication of Neurotropin for pain control of RSD was so effective. We report a case of RDS as a complication of shunt malfunction.     

Ventriculoperitoneal shunt surgery and the incidence of shunt revision in adult patients with hemorrhage-related hydrocephalus

Objective

Ventriculoperitoneal shunt surgery remains the most widely accepted neurosurgical procedure for the management of hydrocephalus. However, shunt failure and complications are common and may require multiple surgical procedures during a patient's lifetime. The purpose of this study is to evaluate the ventriculoperitoneal shunt surgery and the incidence of shunt revision in adult patients with hemorrhage-related hydrocephalus.

Methods

Adult patients who underwent ventriculoperitoneal shunt placement for hemorrhage-related hydrocephalus from October 1990 to October 2009 were included in this study. Medical charts, operative reports, imaging studies, and clinical follow-up evaluations were reviewed and analyzed retrospectively.

Results

A total of 133 adult patients with the median age of 54.5 years were included. Among patients, 41% were males, and 62% Caucasians. The overall shunt revision rate was 51.9%. The shunt revision rate within the first 6 months after the initial placement of ventriculoperitoneal shunts was 45.1%. The median time to first shunt revision was 0.50 (95% CI, 0.24–9.2) months. No significant association was observed between perioperative variables (gender, ethnicity, hydrocephalus type, or hemorrhage type) and the shunt revision rate in these patients. Major causes of shunt revision include infection (3.6%), overdrainage (7.6%), obstruction (4.8%), proximal shunt complication (7.6%), distal shunt complication (3.6%), old shunt dysfunction (6.8%), valve malfunction (10.0%), externalization (3.6%), shunt complication (12.0%), shunt adjustment/replacement (24.0%) and other (16.4%).

Conclusion

Although ventriculoperitoneal shunting remains to be the treatment of choice for adult patients with post hemorrhage-related hydrocephalus, a thorough understanding of predisposing factors related to the shunt failure is necessary to improve treatment outcomes.     

导致成人与儿童患者30天脑室腹腔分流失败的原因分析（英文）

OBJECTIVE The aim of this study was to provide a comprehensive benchmark of 30-day ventriculoperitoneal(VP)shunt failure rates for a single institution over a 5-year study period for both adult and pediatric patients,to compare this with the results in previously published literature,and to establish factors associated with shunt failure.METHODS A retrospective database search was undertaken to identify all VP shunt operations performed in a single,regional neurosurgical unit during a 5-year period.Data were collected regarding patient age,sex,origin of hydrocephalus,and whether the shunt was a primary or secondary shunt.Operative notes were used to ascertain the type of valve inserted,which components of the shunt were adjusted/replaced(in revision cases),level of seniority of the most senior surgeon who participated in the operation,and number of surgeons involved in the operation.Where appropriate and where available,postoperative imaging was assessed for grade of shunt placement,using a recognized grading system.Univariate and multivariate models were used to establish factors associated with early(30-day)shunt failure.RESULTS Six hundred eighty-three VP shunt operations were performed,of which 321 were pediatric and 362 were adult.The median duration of postoperative follow-up for nonfailed shunts(excluding deaths)was 1263 days(range 525-2226 days).The pediatric 30-day shunt failure rates in the authors'institution were 8.8%for primary shunts and 23.4%for revisions.In adults,the 30-day shunt failure rates are 17.7%for primary shunts and 25.6%for revisions.In pediatric procedures,the number of surgeons involved in the operating theater was significantly associated with shunt failure rate.In adults,the origin of hydrocephalus was a statistically significant variable.Primary shunts lasted longer than revision shunts,irrespective of patient age.CONCLUSIONS A benchmark of 30-day failures is presented and is consistent with current national databases and previously published data by other groups.The number of surgeons involved in shunt operations and the origin of the patient's hydrocephalus should be described in future studies and should be controlled for in any prospective work.The choice of shunt valve was not a significant predictor of shunt failure.Most previous studies on shunts have concentrated on primary shunts,but the high rate of early shunt failure in revision cases(in both adults and children)is perhaps where future research efforts should be concentrated.     

Changes in visual acuity associated with shunt failure

OBJECT: The object of this article was to report on a retrospective analysis of the clinical findings in a series of patients with changes in visual acuity associated with shunt failure. METHODS AND RESULTS: Over a 10-year period, 350 patients underwent revisions for shunt failure. The clinical course of patients who demonstrated changes in visual acuity (VA) before or during hospitalization were reviewed; follow-up was achieved using outpatient records and telephone calls with physicians, family, or caregivers. Six patients (4 male) ranging in age from 2.5 years to 40 years demonstrated changes in vision associated with shunt failure. The youngest patient lapsed into coma before transfer and showed bilateral occipital lobe infarctions on the CT scan. Three patients had no complaints referable to the visual system prior to revision. Two patients with symptoms lasting more than 21 days showed unequivocal signs of increased intracranial pressure. Serial CT scans remained unchanged in 2 patients. A 3rd patient showed questionable progression in ventricular volume, while another patient's ventricles dilated after a period of 48-72 h. Four patients demonstrated a pattern of aqueductal stenosis, long-term shunting without revision, small ventricles, and poor outpatient follow-up. Four patients showed partial or complete recovery following revision. CONCLUSIONS: Changes in vision are uncommon and can be an isolated finding associated with shunt failure. Patients with aqueductal stenosis, long-term shunting without revision, and small, potentially non-compliant ventricles may be at risk of this complication. Misdiagnosis or inadequate follow-up places these patients at additional risk, but rapid revision can result in partial or complete recovery.     

Choice of valve type and poor ventricular catheter placement: Modifiable factors associated with ventriculoperitoneal shunt failure

Ventriculoperitoneal (VP) shunt insertion is a common neurosurgical procedure, essentially unchanged in recent years, with high revision rates. We aimed to identify potentially modifiable associations with shunt failure. One hundred and forty patients who underwent insertion of a VP shunt from 2005–2009 were followed for 5–9 years. Age at shunt insertion ranged from 0 to 91 years (median 44, 26% <18 years). The main causes of hydrocephalus were congenital (26%), tumour-related (25%), post-haemorrhagic (24%) or normal pressure hydrocephalus (19%). Fifty-eight (42%) patients required ⩾1 shunt revision. Of these, 50 (88%) were for proximal catheter blockage. The median time to first revision was 108 days. Early post-operative CT scans were available in 105 patients. Using a formal grading system, catheter placement was considered excellent in 49 (47%) but poor (extraventricular) in 13 (12%). On univariate analysis, younger age, poor ventricular catheter placement and use of a non-programmable valve were associated with shunt failure. On logistic regression modelling, the independent associations with VP shunt failure were poor catheter placement (odds ratio [OR] 4.9, 95% confidence interval [CI] 1.3–18.9, p = 0.02) and use of a non-programmable valve (OR 0.4, 95% CI 0.2–1.0, p = 0.04). In conclusion, poor catheter placement (revision rate 77%) was found to be the strongest predictor of shunt failure, with no difference in revisions between excellent (43%) and moderate (43%) catheter placement. Avoiding poor placement in those with mild or moderate ventriculomegaly may best reduce VP shunt failures. There may also be an influence of valve choice on VP shunt survival.     

Blocked ventriculoperitoneal shunt causing raised intracranial pressure diagnosed by prominent sinus pericranii

We present a 3.5-year-old male infant who had been treated at 3 weeks of age with a ventriculoperitoneal (VP) shunt for intraventricular haemorrhage with resultant hydrocephalus. Since his initial treatment he had normal developmental milestones. On this occasion he presented with difficulty in walking, vomiting and irritability. His mother was concerned this was due to his shunt malfunctioning. It had not required revision since insertion as a neonate. He was initially managed at a peripheral hospital without neurosurgical services for 4 weeks as an outpatient. The major clinical concern was a gradually enlarging lesion confined to the top of his head consistent with a vascular malformation. Investigations were focused towards this, with an initial diagnosis made of a cerebral arteriovenous malformation (AVM) with involvement of scalp vessels. His initial head CT scan did not show enlarged ventricles and the shunt was clinically assessed as functioning satisfactorily. The patient’s condition worsened and he was referred with a diagnosis of scalp AVM for neurosurgical attention. After neurosurgical review a clinical diagnosis of raised intracranial pressure (ICP) due to shunt malfunction was made. This was supported by a CT scan that showed an enlarging ventricular system. After revision of the shunt there was complete resolution of the pulsatile scalp swelling with clinical recovery of the child. To our knowledge this is the first reported incidence of a blocked VP shunt causing raised ICP presenting with a localised extracranial pulsatile venous dilation consistent with a “true” sinus pericranii.     

Reversible porencephaly

The cases of four infants (five lesions) are reported, where porencephalic cysts, located along the ventricular catheter after shunt malfunction and ommaya reservoir insertion, disappeared after ventriculoperitoneal (VP) shunt revision and combined cyst peritoneal (CP) shunt, or after VP shunt alone. This pathological state is thought to be a rare postoperative complication. Its pathogenesis and therapy are discussed. Shunt malfunction or Ommaya reservoir insertion may result in a hypertensive hydrocephalic state. Cerebrospinal fluid (CSF) flows out through a catheter penetrating the site of the ventricular wall and expands in the surrounding white matter to form a porencephalic cavity. Once this porencephalic state occurs, it will not disappear spontaneously because the CSF flows in one direction. As treatment for closed porencephaly, CP shunt following a VP shunt revision was markedly effective; for communicating porencephaly, a VP shunt revision alone was effective.     

Clinical analysis of shunted hydrocephalic neonates and sucklings--observation on obstruction and infection of shunting system

Although ventriculoperitoneal (V-P) shunt is common as the surgical procedure for hydrocephalus, mechanical malfunction and infection are the most significant problems. Despite the current use of variety of mechanical shunting systems, shunt malfunction remains a major problem in pediatric neurosurgical practice. Pathological lesions associated with malfunctioning shunts have been studied only infrequently. From April 1980 to December 1987, we experienced 96 cases of V-P shunt in neonates and suckling. The therapeutic results of shunting and causes of initial shunt revision in those cases with nontumoral hydrocephalus were studied. Of 96 cases, which included 55 cases of congenital and 41 cases of acquired hydrocephalus, in which a V-P shunt had been performed, those cases with no history of shunt revision or with only elective shunt revision during the 5-year follow-up period were classified as successful shunt. The 56 of 96 cases (58.3% successful shunts included 15 of 24 patients with myelomeningocele, 7 of 10 with encephalocele, 12 of 21 with various types of cerebral anomaly, 12 of 22 with posthemorrhagic hydrocephalus and 10 with postmeningitic hydrocephalus. There were 12 successful shunts performed in 27 premature and 44 in 69 mature infants. The 40 patients (41.7% with non-elective shunt revision included 5 with breakdown of the sutured scalp with cerebrospinal fluid leakage, 20 with obstruction of the shunt system (14 ventricular side, 6 abdominal side, and 15 with infection. During the 5-year follow-up period 11 died and 85 survived 88.5%), of whom 43 (44.8%) showed normal intellectual development and 42 (43.7%) showed developmental disability.     

Risk Factors and Surgical Treatment for Symptomatic Adjacent Segment Degeneration after Lumbar Spine Fusion

Objective

The present study analyzed the risk factors, prevalence and clinical results following revision surgery for adjacent segment degeneration (ASD) in patients who had undergone lumbar fusion.

Methods

Over an 8-year period, we performed posterior lumbar fusion in 81 patients. Patients were followed a minimum of 2 years (mean 5.5 years). During that time, 9 patients required revision surgery due to ASD development. Four patients underwent autogenous posterolateral arthrodesis and extended transpedicle screw fixation, 4 patients underwent decompressive laminectomy and interspinous device implantation, and 1 patient underwent simple decompression.

Results

Of the 9 of patients with clinical ASD, 33.3% (3 of 9) of patients did not have radiographic ASD on plain radiographs. Following revision surgery, the clinical results were excellent or good in 8 patients (88.9%). Age > 50 years at primary surgery was a significant risk factor for ASD development, while number of fusion levels, initial diagnosis and type of fusion were not.

Conclusion

The incidence of ASD development after lumbar surgery was 11.1% (9 of 81) in this study. Age greater than 50 was the statistically significant risk factor for ASD development. Similar successful clinical outcomes were observed after extended fusion with wide decompression or after interspinous device implantation. Given the latter procedure is less invasive, the findings suggest it may be considered a treatment alternative in selected cases but it needs further study.     

A Retrospective Analysis of Ventriculoperitoneal Shunt Revision Cases of a Single Institute

Objective

Ventriculoperitoneal (VP) shunt complication is a major obstacle in the management of hydrocephalus. To study the differences of VP shunt complications between children and adults, we analyzed shunt revision surgery performed at our hospital during the past 10 years.

Methods

Patients who had undergone shunt revision surgery from January 2001 to December 2010 were evaluated retrospectively by chart review about age distribution, etiology of hydrocephalus, and causes of revision. Patients were grouped into below and above 20 years old.

Results

Among 528 cases of VP shunt surgery performed in our hospital over 10 years, 146 (27.7%) were revision surgery. Infection and obstruction were the most common causes of revision. Fifty-one patients were operated on within 1 month after original VP shunt surgery. Thirty-six of 46 infection cases were operated before 6 months after the initial VP shunt. Incidence of shunt catheter fracture was higher in younger patients compared to older. Two of 8 fractured catheters in the younger group were due to calcification and degradation of shunt catheters with fibrous adhesion to surrounding tissue.

Conclusion

The complications of VP shunts were different between children and adults. The incidence of shunt catheter fracture was higher in younger patients. Degradation of shunt catheter associated with surrounding tissue calcification could be one of the reasons of the difference in facture rates.     

Influence of the shunt type in the difference in reduction of volume between the two lateral ventricles in shunted hydrocephalic children

Introduction After shunt insertion there is commonly a disproportionate reduction in size of the lateral ventricle containing the catheter (shunted lateral ventricle), which is almost certainly related to shunt function. To explore the difference between two shunt types, the Differential Pressure Medium Pressure cylindrical (M.P.) and Delta 1.5 valves (manufactured by P.S. Medical, Goleta, CA, USA), we measured lateral ventricle volumes preoperatively and after 3 months, using segmentation techniques on CT or MR scans.Materials and methods There were 40 patients (mean age 65.7 months), 17 with M.P. and 23 with Delta valves. There were 22 new shunts (8 M.P. and 14 Delta), and 18 revisions (9 M.P. and 9 Delta). Shunted to non-shunted ventricle volume ratios and the difference in ratios (preoperative to 3 months) was calculated. A ratio considerably less than 1 would indicate disproportionate reduction in the volume of the shunted ventricle in comparison to the non-shunted one.Results In the new shunt group, the preoperative ratio was 1.63 for M.P. and 1.07 for Delta (p=0.148, one-way ANOVA). The 3-month ratio was 0.71 for M.P. and 1.44 for Delta. The difference in ratios was 0.91 for M.P. and –0.36 for Delta (p=0.042, one-way ANOVA). There were 4 shunt obstructions in this group (3 with M.P. and 1 with the Delta valve). In the revision group, the preoperative ratio was 0.85 for M.P. and 0.88 for Delta (p=0.859, one-way ANOVA). The 3-month ratio was 0.74 for M.P. and 0.60 for Delta. The difference in ratios was 0.11 for M.P. and 0.27 for Delta (p=0.274, one-way ANOVA). There were 5 shunt obstructions in this group (2 with M.P. and 3 with the Delta valve). No correlation was found between incidence of shunt obstruction and shunt type or ventricular volume ratio difference (preoperative to 3 months) in either of the two operation groups.Conclusions Following new shunt insertion, the presence of a differential pressure valve results in early significant reduction in the shunted lateral ventricle volume. This may predispose to shunt obstruction although this study has not proven this. This effect was not observed with the Delta valve after 3 months. Following shunt revision, no difference between the two valve types was observed. This may indicate a chronic effect of the presence of a shunt on the ventricular system size, obviating the effect of different shunt types. The material of this paper has been presented at the Third International Hydrocephalus Conference, Chicago, USA, 29 May 2002 and the 18th Congress of the European Society for Pediatric Neurosurgery, Kiruna, Sweden, 15 June 2002 The authors have no financial interests in any of the valves assessed in the paper     

A peritoneal marker for optimal timing of ventriculo-peritoneal shunt revision in early childhood

Abstract

The ventriculo-peritoneal shunt placed in a neonate or infant needs revision to lengthen the peritoneal tube at certain times during childhood. The critical time for this revision is not exactly the same between individuals. Furthermore, the level of peritoneal insertion of the shunt tube is often unclear on x-ray films. To plan for and determine the optimal timing of revision, we applied a titanium clip on the peritoneal suture line in three infants as a marker of peritoneal insertion level. During the 31- to 37-month follow-up period, abdominal x-ray clearly demonstrated the peritoneal insertion level in all three patients, allowing accurate determination of the length of the intraperitoneal portion OP) of the shunt tube. The rate of shortening of the length of IP was 20 to 27% of the increase in body height (BH). This technique allows accurate determination of the length of IP and also optimal timing for revision. [Neural Res 1998; 20: 526-528]     

A rare case of shunt malfunction attributable to blockage of a Codman-Hakim programmable shunt valve

BACKGROUND: We report a rare case of shunt malfunction resulting from blockage of a Codman-Hakim programmable shunt valve by fibrinoid-like tissues. HISTORY: The patient had undergone shunt system placement for hydrocephalus after hemorrhagic infarction at the age of 8 months; a Codman-Hakim programmable shunt valve was used at that time. LATER COURSE: Two years after shunt placement, the boy suffered from irritability and poor activity when the aforementioned shunt malfunction arose following valve blockage by fibrinoid-like tissues. He underwent shunt revision and was subsequently free of symptoms.     

Occurrence and management of fractured peripheral catheters in CSF shunts

A series of 716 children underwent 2065 cerebrospinal fluid shunt procedures. Shunt failure due to fracture of the peripheral drain occurred 60 times, 38 times in ventriculo-atrial and 22 times in ventriculo-peritoneal shunts. The break occurred most commonly 2–4 cm above the neck incision in cardiac and just cephalad to the clavicle in abdominal drains. Fifty-nine ruptures occurred in Pudenz catheters (which were used in 82% of the shunts) and 1 occurred in a Holter drain (used in 17%). The fractured atrial catheters remained in situ (5/38) or were dislodged into the right cardiac ventricle (14/38), pulmonary arteries (9/38), right atrium (5/38) or hepatic veins (3/38). Two of the ruptured drains could not be located. Removal by a percutaneous transvascular snare technique was attempted in 27 cases and was successful in 24.     

Cerebrospinal fluid galactorrhea: a rare complication of ventriculoperitoneal shunting.

In this report we describe a 26-year-old woman who had an intra-abdominal pseudocyst located at the peritoneal catheter tip following ventriculo-peritoneal (VP) shunt implantation. Retrograde cerebrospinal fluid (CSF) flowed outside the catheter and communicated with the right breast lactiferous ductal system and leaked from the nipple orifice. CSF galactorrhea only occurs when the lactiferous duct is injured during VP shunt implantation, in combination with the formation of an intra-abdominal CSF pseudocyst prior to lactiferous duct healing. Leakage of CSF from the nipple orifice can be successfully treated by simply guiding the peritoneal catheter tip into the peritoneal cavity through a new laparotomy; that is, shunt revision is not always required.     

The Medos Hakim programmable valve in the treatment of pediatric hydrocephalus

The programmable Medos Hakim valve offers the possibility of adjusting the valve's operating pressure noninvasively. We retrospectively analyzed a series of 78 children who underwent a shunting procedure using this programmable valve within the last 4 years: 46 children underwent a primary shunt placement and 32 children underwent a shunt revision with a different valve replaced by the Medos programmable valve. There were 23 complications, 9 infections, 13 mechanical complications and 1 subileus in all children. Treatment was successful with no need for further shunt revision in 29 of the children with primary shunt placements and 27 of the children with shunt revisions. In 10 cases of overdrainage this was adequately corrected by readjustment of the valve operating pressure alone. As there are no criteria for prediction of the valve operating pressure needed for any individual patient we consider this valve to be beneficial in various forms of shunt-dependent pediatric hydrocephalus.