INTRODUCTION
Hydrocephalus is a pathological condition of cerebroventricular system, marked by an abnormal accumulation of cerebrospinal fluid (CSF) results from an imbalance between the production and absorption. Historically, the gold standard for treating hydrocephalus has been the ventriculoperitoneal shunt (VPS), a technique pioneered by Kausch in 19081).
Although VPS implantation is a simple and common neurosurgical procedure, this procedure has been associated with a significant number of complications ranging from 17% to 33%2), and it was demonstrated that children exhibit a higher incidence of shunt-related complications1). Due to the significant prevalence of shunt-related complications and failures, neuroendoscopic third ventriculostomy (ETV) has gained favor as an alternative therapeutic approach3).
Shunt malfunctions can be categorized into proximal shunt malfunctions and distal shunt malfunctions, based on their anatomical location2). Proximal shunt malfunctions, a primary cause of shunt failure, originate from obstructions at the shunt tip, often attributed to pathological or natural tissues such as choroid plexus, glial tissue, and connective tissue2,3). Conversely, distal shunt malfunctions requiring a shunt revision occur varies from 5% to 47%4) and may result from various factors, including bowel perforations and pseudocyst formation, catheter mechanical obstructions, shunt infections, shunt migration, and sporadic instances of shunt protrusion2).
When shunt malfunctions occur, surgical intervention, such as VPS revision is often required, depending on the patient's clinical condition. This may sustain significant economic burdens. Despite exhaustive efforts to prevent shunt malfunctions a definitive solution remains elusive2).
In this paper, we aim to share our experience with laparoscopy as an effective tool for managing distal catheter malfunctions in patients who underwent VPS. Additionally, we provide a review of previously published literature concerning this subject.
CASE
Case 1
A 72-year-old male patient presented to the emergency department one month ago with a decreased level of consciousness and episodes of vomiting. He had previously undergone VPS surgery at an external facility due to hydrocephalus secondary to a cerebellar intracerebral hemorrhage three years earlier. Clinical examination revealed an unresponsive state and altered mental status. Comparative analysis of brain CT scans from the previous medical institution and the current evaluation showed an increase in the Evans ratio from 0.28 to 0.35, along with periventricular edema.
Subsequent investigations were performed to assess the integrity of the shunt system, including X-rays of the skull, chest, and abdomen, all of which demonstrated normal valve pressure settings and catheter continuity5). Additionally, CSF analysis obtained via lumbar puncture showed no signs of infection. After ruling out infection, a shuntography was performed.
Shuntography5) confirmed contrast injection into the ventricles (Fig. 1A) but failed to visualize the contrast in the abdominal domain, suggesting distal catheter obstruction (Fig. 1B). As a result, laparoscopic exploration was undertaken using a single port (LapSingle port). Laparoscopy confirmed that the distal catheter tip was obstructed by omental adhesions (Fig. 1D), approximately 3 cm of the distal catheter was truncated, and subsequent CSF drainage was successfully observed.
One week after the procedure, a follow-up brain CT scan revealed a return to normal Evans ratio, decreasing from 0.35 to 0.28. The patient fully recovered to his pre-decompensation state without any complications.
Case 2
A 49-year-old female patient presented to the emergency department with persistent headaches and dizziness over the past 48 hours. She had a history of VPS surgery for post-traumatic hydrocephalus performed two decades ago at an external medical facility. Clinical evaluation revealed a drowsy mental status, ongoing headaches, and vomiting. Brain CT imaging revealed an increase in the Evans ratio from 0.08 to 0.30 with periventricular edema (Fig. 1C). X-rays of the skull, chest, and abdomen were performed to confirm the valve pressure settings and shunt catheter integrity as established by the external medical facility. the valve pressure was appropriate and catheter continuity was intact. Subsequent CSF analysis obtained via lumbar puncture showed no signs of infection.
After ruling out infection, shuntography was performed, confirming contrast injection into the ventricles but failing to show its transit into the abdominal cavity. Subsequent laparoscopic exploration via a dual-port laparoscope. Unfortunately, CSF drainage was not observed through this segment. It was hypothesized that the slit portion of the distal catheter was the likely cause of the malfunction6) and the decision was made to trim and excise this portion. Post-truncation, laparoscopy confirmed effective cerebrospinal fluid drainage from the revised distal catheter (Fig. 1E).
Following the intervention, the Evans ratio returned to baseline (Fig. 1F), decreasing from 0.30, and the patient’s symptoms improved, allowing for her discharge. Bacterial cultures of the excised distal catheter showed no microbial growth, and no further complications related to the procedure were observed.
DISCUSSION
Neuroendoscopy has emerged as a viable alternative for select patients. And the integration of endoscopy into neurosurgery has led to various applications since the introduction of endoscopic ventriculostomy by Stookey and Scarff in 19361). Additionally, endoscopy has become an important part of the therapeutic option for hydrocephalus4), including in the context of VPS procedures. The use of endoscopy to excise peritoneal catheters in cases of VPS malfunction was first reported in 1973 by Jean-Louis Lemay and colleagues7). And Fiberoptic endoscopy has been recognized for its utility in VPS surgeries and shunt revisions since the early 1990s8).
Laparoscopy for VPS malfunction caused by distal catheter issues is mainly applicable when simple laparotomy is difficult due to obesity, previous abdominal surgery, or distorted anatomy. Such cases are often directly linked to distal mechanical shunt failure from adhesions, calcification, and fibrosis causing catheter obstruction, malposition, and migration2,4). In these situations, collaboration with a general surgeon may be considered.
Several studies strongly recommend laparoscopy for obese patients and those with prior abdominal surgeries4). However, laparoscopy in VPS patients has limitations. VPS was long regarded as an contraindication to laparoscopy due to concerns about increased intracranial pressure from intraabdominal insufflation, which could potentially lead to cerebral herniation. However, recent research indicates that the risk of retrograde failure of the valve system remains minimal, even with intraabdominal pressures reaching up to 80 mmHg9). And in distal catheter-related VPS malfunction, the obstruction of the distal catheter may reduce the impact of VPS-related limitations.
A review of the existing literature on endoscopy and laparoscopy in VPS surgeries and revisions reveals three main approaches (Table 1).
First, laparoscopic distal catheter placement: This technique employs endoscopy for distal catheter insertion during VPS surgery. It is especially beneficial for patients at risk of peritoneal adhesions, those who are obese, or those with altered abdominal anatomy10). although some argue that laparoscopic distal catheter insertion, compared to laparotomy, It has been recognized as effective in reducing complications and hospital costs11).
Second, management of the proximal or ventricular catheter through endoscopic shunt revision: Research on proximal catheter insertion using endoscopy has mainly focused on pediatric patients. This includes endoscopic third ventriculostomy or endoscopic septostomy, both of which remain viable therapeutic options. However, these techniques have not demonstrated a significant reduction in revision rates8).
Third, management of the distal or peritoneal catheter through laparoscopic shunt revision: laparoscopy is used during shunt revision procedures to address the peritoneal catheter. Laparoscopy allows direct abdominal exploration facilitates the identification of incidental pathology and effectively resolves distal catheter malfunction and underlying issues that may lead to recurrence4). Laparoscopic distal catheter truncation, adhesiolysis, repositioning, and catheter exchange can be used to manage distal catheter-related VPS malfunction. Additionally, as observed in the review, minimal invasive laparoscopic “sling” techniques such as falciform ligament penetration or peritoneal suturing for distal catheter fixation can further enhance its intraperitoneal stability10,12).
In this study, VPS malfunctions caused by peritoneal catheter issues were managed using a proprietary protocol (Fig. 2) to identify patients who met specific inclusion criteria for a laparoscopic approach.
For patients with a VPS, an initial imaging evaluation determines the urgency of treatment. If a patient has decreased consciousness and signs of increased intracranial pressure, a non-contrast brain CT scan is performed first. If ventriculomegaly is detected, emergency external ventricular drainage is done immediately. The patient is then closely monitored until stable, after which a full assessment begins.
For cases with typical hydrocephalus symptoms—such as gait ataxia, memory impairment, and urinary incontinence— a non-contrast brain CT scan is performed. If ventriculomegaly is present, the first step is to check if the current valve pressure matches the previous setting. If the current valve pressure is higher than before, it is adjusted, and the patient's condition is observed. A follow-up brain CT scan is done within a week to check if the ventricles have decreased in size, though this may be done sooner depending on symptom improvement. If the patient’s symptoms do not improve or worsen significantly, a brain scan may be performed sooner.
If valve pressure remains unchanged or decreases, a shunt system malfunction is considered. The functionality of the implanted valve and the continuity of the catheter are assessed through manual shunt pumping and simple radiography (skull, chest, and abdomen). If a malfunction is detected—such as valve dysfunction or catheter discontinuity—the device is removed, and a revision procedure is performed.
If there is no issue with the shunt system, a central nervous system (CNS) infection is considered. A CSF sample is taken by inserting a needle into the shunt valve reservoir or through a spinal tap to check cell count and detect infection. If a CNS infection is confirmed, the distal catheter is externalized, and antibiotics are given. Once infection control is confirmed through repeated CSF tests, a revision surgery is performed.
If a CNS infection is ruled out, shuntography is done to find the cause of the malfunction. Fluoroscopy-guided contrast injection into the valve reservoir is used to track contrast flow through the shunt system. Additional brain or abdominal CT scans may help confirm the findings. If shuntography shows a problem with the valve or proximal catheter, revision surgery is done. If the distal catheter is the issue, laparoscopic adhesiolysis or trimming is considered.
After surgery, an immediate brain CT scan is performed to check ventricular size. Depending on symptom changes, another follow-up brain CT scan is done within a week to assess further reduction in ventricular size and confirm treatment success.
When managing VPS malfunction related to the distal catheter, a laparoscopic approach is inevitably compared to simple peritoneal catheter replacement. This is because the procedure itself is not highly complex. However, based on our experience, laparoscopic VPS revision offers advantages over simple distal catheter replacement. It shortens operative time, minimizes abdominal wall trauma and postoperative complications by reducing incision size, peritoneal and fascial openings, secondary adhesions, postoperative pain, ileus, organ perforation, and incisional herniation4,10).
And most importantly, this laparoscopic approach eliminates the need for additional incisions and manipulation around the shunt valve, which are typically required during catheter replacement and may increase the risk of shunt infection or valve malfunction. An alternative method involves cutting the distal catheter at the abdominal wall and connecting a new one using a connector. While this avoids valve manipulation, it leads to luminal narrowing due to the connector’s thickness, making it less preferable than laparoscopic revision.
This case report discusses two cases and outlines the protocol followed at our institution. Although this protocol was developed from extensive clinical experience with shunt malfunctions, its generalizability remains limited. To draw more broadly applicable conclusions, additional case studies and more comprehensive, structured research are required.
CONCLUSION
In summary, laparoscopic management of shunt malfunction can be effectively applied in cases of distal catheter occlusion. In cases where the etiology is non-infectious and related to the distal or peritoneal catheter, laparoscopy has proven to be an effective modality for mitigating VPS malfunctions without the need for shunt device removal or replacement. To derive a general applicable conclusion, additional case studies and more comprehensive, systematic research are required.
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