Highlights
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• Canadian neurosurgeons have differing attitudes to laparoscopic assistance (LA) in ventriculoperitoneal (VP) shunt surgery. They identify no major barriers to LA.
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• Infection and catheter obstruction are the most consistent post-operative complications in VP shunt surgery.
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• Participants reported LA may reduce the risk of distal catheter malposition but not other complications.
Introduction
Since its inception in the early 1900s, cerebrospinal fluid diversion via shunting to the intraabdominal cavity has been a mainstay in the treatment of hydrocephalus resulting from a broad range of etiologies, including normal pressure hydrocephalus, post-hemorrhagic, post-infectious and obstructive causes, among others. While several terminal locations for the distal shunt catheter have been well-described, the peritoneal cavity (ventriculoperitoneal, or VP shunt) remains the most common and is often the first-line choice in routine adult patients for distal catheter placement. Although there are clear indications for alternative terminal shunt placements, these fall outside the scope of this study, as they are not amenable to laparoscopic assistance (LA). Likewise, while pediatric VP shunting is prevalent, there are distinct technical differences between adult and pediatric procedures, as well as unique risk profiles. Accordingly, this study focused exclusively on adult VP shunting.
Historically, neurosurgeons have performed the entirety of insertion of the intraventricular proximal shunt catheter and valve, as well as the abdominal opening for the placement of the distal catheter. After subcutaneous tunneling of the catheter along the neck and externalization in the subcostal region, a mini-laparotomy in the upper right quadrant allows for the distal catheter’s entry into the peritoneal cavity. This approach has become highly efficient and standardized at most centers; however, VP shunt placement using this method still carries a complication rate of up to 30%. These complications include infection, shunt obstruction, distal catheter misplacement, hemorrhage, over-drainage, under-drainage and post-operative pain. Reference Phan, Liao and Jia1 While not exhaustive, this list comprises the most commonly discussed complications with patients.
A large multicenter study Reference Mansoor, Solheim, Fredriksli and Gulati2 suggested that proximal occlusion of the shunt is the most common complication, occurring in 30% of cases, followed by infection at 20%. Misplacement of the abdominal catheter at the time of placement is estimated to occur in up to 14% of patients. In general, overall complications are more likely to arise within the first post-operative year (21%) compared to the second (5.7%) and third (2.5%) years. Reference Mansoor, Solheim, Fredriksli and Gulati2
LA surgery, introduced in the early 1900s, has become the gold standard for various general surgical procedures, including cholecystectomy, appendectomy and elective bowel resection, due to its minimally invasive nature, reduced skin infections and faster recovery. Despite the near-simultaneous emergence of VP shunting and laparoscopic surgery, the first published case series of LA VP shunt placement appeared only in 1993, involving six pediatric patients. Reference Basauri, Selman and Lizana3 Subsequent case series demonstrated its feasibility as a safe, non-inferior alternative to mini-laparotomy. Reference Kirshtein, Benifla and Roy-Shapira4,Reference Khaitan and Brennan5 Two randomized controlled trials from Israel and Switzerland in 2014 and 2015, respectively, found no significant differences in operative time or complication rates between the approaches, despite expectations of improved outcomes with LA. Reference Schucht, Banz and Trochsler6,Reference Nigim, Thomas and Papavassiliou7 Retrospective studies, including two large multicenter analyses from the USA, reported lower distal shunt failure rates with LA, Reference Naftel, Argo and Shannon8,Reference Khalid, Nunna and Maasarani9 with one also showing reduced operative times. Reference Naftel, Argo and Shannon8 Additional smaller studies suggest benefits such as reduced distal shunt failure, Reference Dowlati, Shashaty and Carroll10 shorter operative times Reference Alyeldien, Jung, Lienert, Scholz and Petridis11 and lower catheter misplacement rates. Reference Schucht, Banz and Trochsler6,Reference Alyeldien, Jung, Lienert, Scholz and Petridis11,Reference Bani, Telker, Hassler and Grundlach12 However, no studies to date have shown significant differences in infection rates, and some cohort analyses found no overall difference in complications. Reference Gravbrot, Aguilar-Salinas, Walter and Dumont13,Reference Roth, Sagie, Szold and Elran14 Critics argue that small sample sizes, modest effect sizes and study design limitations hinder definitive conclusions. Reference Abdelmageed, Sarkar, Shlobin, Davila and Potts15 A recent meta-analysis of 18 studies found that LA in VP shunt surgery was associated with a 4.9% absolute reduction in distal catheter malfunction, a 17.1-minute reduction in operative time and a 1.3-day shorter hospital stay. Reference Li and Hu16
There has been only one study comparing mini-laparotomy versus LA in the Canadian population, Reference Fahy, Tung, Lamberti-Pasculli, Drake, Kulkarni and Gerstle17 and it was conducted in the pediatric population. The primary barriers to successful clinical trials on this issue in Canada include the greater geographic distance between fewer neurosurgeons compared to other countries, as well as a diffuse population density, which results in each neurosurgical center having access to relatively fewer shunt cases per year. Since the existing primary literature on outcomes comparing classic mini-laparotomy to LA placement of VP shunts is primarily limited to single-center studies or international multi-center studies, the present study aims to examine the surgical approach to VP shunting in a Canadian context.
A survey of practicing Canadian neurosurgeons is an important first step in understanding the current state of the field on this issue. The objective of the current study is to determine whether Canadian neurosurgeons favor a LA technique for primary VP shunt placement compared to mini-laparotomy. We anticipate that the results of this study could provide valuable insight into whether Canadian neurosurgeons consider LA a first-line approach for first-time VP shunt placement in otherwise uncomplicated patients, and offer a foundation for follow-up clinical studies to establish evidence-based recommendations.
Methods
To establish a systematic consensus of opinions from practicing Canadian neurosurgeons, this study utilized a modified Delphi methodology. Reference Hsu and Sandford18 Local Research Ethics Board approval (Pro00128728) was obtained, and consent for participation was implied by submission of the survey responses. The study population was composed of currently practicing Canadian neurosurgeons who treat adult patients and who routinely insert VP shunts. In Round 1, an initial survey instrument (Supplementary Material) based upon best practices and primary complications of VP shunt placement was constructed based on information from a review of the literature. Reference Phan, Liao and Jia1–Reference Bani, Telker, Hassler and Grundlach12 Specifically, we posed questions relating to cases of adult VP shunt placement. All other patients and shunt types were excluded. It is foreseeable that the debate between mini-laparotomy and LA could be controversial, and thus, ensuring participant anonymity in the survey may prevent external biases from influencing individual opinions.
The instrument comprised items focused on issues described in the existing literature with rank-ordered responses, as well as open-ended items to allow for exploration and input from respondents regarding potential additional issues. Once completed, the initial survey instrument was piloted with practicing neurosurgeons at a single Canadian center to assess construct validity and allow for refinement of the items from their feedback. Once validation of the piloted instrument was complete, the first instrument was distributed nationally exclusively to practicing neurosurgeons across Canada through the Canadian Neurosurgical Society and the Canadian Neurosurgery Research Collaborative, the latter of which is a resident-led organization allowing for in-person solicitation of survey completion at Canadian academic centers. The instrument was distributed via email using the SurveyMonkey.com® platform to eligible participants. Survey responses were anonymous aside from center of practice.
Responses from the first round of distribution were analyzed for consensus and conflicting opinions. Itemized responses were compiled using descriptive statistics and summarized using percentages. “Consensus” was defined here as an achieving >50% agreement between respondents. Low-priority items that achieved consensus were eliminated, and the survey was refined into a second iteration, which was subsequently redistributed following the same methodology as above. Both survey instruments are provided in the Supplementary Material.
Results
In the first round, there were 29 respondents, with 19 (65.5%) reporting experience with LA. A majority (21, or 72.4%) indicated that their center did not exhibit bias either for or against LA, while 1 (3.4%) reported a bias against it (Figure 1). This finding aligns with the 3.4% of respondents who believed LA was always inferior to mini-laparotomy (discussed later).
Figure 1. Representation of participants from each province.
Consensus was not reached regarding the relative rates of common postoperative complications or the impact of LA on these complications. However, in patients undergoing VP shunt revision, 22 (75.8%) identified distal catheter obstruction as either the first or second most important complication. Infection was ranked as the most important complication by 12 (41.4%) of respondents and as one of the top two by 17 (58.6%). Conversely, visceral injury was considered the least common complication (Figure 1). Although 16 complications were listed as options, only 5.4% of respondents ranked more than five, and none ranked more than seven. Regarding hospital length of stay following VP shunt placement, 23 (79.3%) believed it would be similar with or without LA, while 13.8% suggested that LA could reduce hospital stay duration.
In the second iteration of the survey, participation increased to 36 respondents. This round specifically inquired about the center of practice to ensure national representation, which included institutions from British Columbia (University of British Columbia, University of Victoria, Kelowna General Hospital), Alberta (University of Alberta, University of Calgary), Saskatchewan (University of Saskatchewan), Manitoba (University of Manitoba), Ontario (University of Toronto, Sunnybrook Hospital, Hamilton Hospital, London Hospital, Kingston Hospital, Windsor Hospital, McMaster University, Ottawa Hospital) and Nova Scotia (Dalhousie University) (Figure 1).
Consensus was reached on five out of eight topics in the second iteration. Notably, 32 (91.4%) of respondents reported no institutional pressure regarding the use of LA, and 11 (44%) agreed that personal preference was the primary factor influencing its use (Figure 2). A small number of respondents reported a complication rate of >20% for only proximal catheter obstruction or distal catheter fracture. Distal catheter malposition remained the complication most frequently predicted to be reduced by LA, with 52.9% estimating at least a 30% reduction and 42% predicting a reduction of over 50% (Table 2).
Figure 2. Summary of round one responses. Q1) experience with laparoscopic assistance, Q2) local opinion of laparoscopic assistance and Q3) common complications following VP shunt surgery in general.
Table 1. Summary of responses from round 1 whether laparoscopic assistance could theoretically reduce the risk of common VP shunt complications
Table 2. Estimated theoretical risk reduction from round two respondents for common post-operative VP shunt complications, if laparoscopic assistance were to be used
Discussion
Although there is ongoing controversy, the majority of studies examining the outcomes in LA VP shunt placement have suggested non-inferiority of LA to mini-laparotomy. In some cases, previous studies have suggested reduced distal catheter complications, decreased hospital length of stay and improved operative times with the LA approach. All other metrics of outcomes, including infection, were not reliably reduced by the LA approach based on the existing literature. Reference Kirshtein, Benifla and Roy-Shapira4–Reference Li and Hu16 There are currently no formal recommendations suggesting the LA approach be considered standard of care. Anecdotally, many Canadian centers currently performing these procedures do not utilize laparoscopy for initial shunt placement as standard protocol. However, there is no published data regarding the predominant modern practice patterns for this procedure in Canada. The mini-laparotomy approach has been engrained in the global neurosurgery community as the gold-standard approach for more than 100 years, while laparoscopy remains an emerging technique utilized for VP shunts over only a fifth of that time. Thus, it is possible that surgeons may be hesitant to endorse the benefits of laparoscopy if there is no clear consensus among their peers or community. For these reasons, we suggest that the Delphi approach to gauging opinion within the Canadian neurosurgery community is an important first step toward a consensus recommendation on the utilization of LA of primary VP shunts, as well as to serve as a foundation to a possible future Canadian clinical trial, which would likely require multi-center engagement.
The first round revealed several trends which were in line with current evidence, including 75% who thought LA would not improve infection risk, similar to previous studies, Reference Gravbrot, Aguilar-Salinas, Walter and Dumont13,Reference Roth, Sagie, Szold and Elran14,Reference Abdelmageed, Sarkar, Shlobin, Davila and Potts15 and 67.8% who did not think it would help to prevent abdominal pseudocyst (Table 1). A total of 93% thought it would reduce the risk of distal catheter malposition (Table 1), which is also supported by previous studies. Reference Schucht, Banz and Trochsler6,Reference Alyeldien, Jung, Lienert, Scholz and Petridis11,Reference Bani, Telker, Hassler and Grundlach12 The literature suggests that operative times could be reduced via LA, though this was not reflected in opinions recorded in round one participants. It was pointed out by several of the respondents in the free-form spaces that while transitioning to an LA approach at a center, operative times may be transiently increased, due to required system-level adjustments, before decreasing in the long-term once optimized and more familiar. Thus, this topic was rephrased and re-interrogated in the second round; this time 71% agreed that eventually operative times would decrease once experience was established.
Overall representation nationally by the second round was broad, with at least one center from all provinces except the Northwest Territories, Nunavut, Prince Edward Island (which do not have any practicing neurosurgeons or neurosurgical facilities), Newfoundland and New Brunswick (which do not have academic neurosurgical centers). We therefore feel that we have captured a reasonable sense of the state of LA for VP shunts in Canada at the time of survey, although several provinces were represented by low number of respondents. For the 3 topics in which consensus was not reached by the end of the second round (access limitations to LA, LA role in revision surgery and distal catheter malposition reduction effect size), we did not feel that additional rounds of the instrument would be likely to achieve consensus. This is likely attributable to the relatively low quality of existing data, unique practice patterns across the country and the controversial and/or subjective nature of the issues.
From round 2 of the survey, participants generally thought that there were no major institutional barriers to LA in VP shunt surgery (with 80% reporting either personal preference alone or no barriers at all). In total, 20% reported not having access to general surgery personnel at their center to use LA if they wished (Figure 3). In terms of complications, 77.8% ranked infection, 82.9% distal catheter obstruction and 69.4% proximal obstruction in shunt placement as up to 10% risk per VP shunt surgery for each (Supplementary Table 1), which is in line with the published literature. Although there was consensus on these top three complications between participants, 58% also thought that unrelated comorbidities would ultimately have the greatest impact on hospital length of stay rather than complications related to shunt placement (Figure 3 ). This has interesting implications for the perceived impact of LA, as there was no consensus among participants that these complications would be appreciably modified by LA (Table 2). In round one, 93% thought that LA could reduce distal catheter malposition rate, and this was further developed in round two to highlight that >50% of respondents thought it could reduce the risk of malposition by at least 30%. Distal catheter malposition in particular should theoretically be reduced by LA, given this is a direct visualization procedure (inclusive of the final position of the catheter tip in the abdomen and the bowels) as opposed to the semi-blind procedure of mini-laparotomy. This idea is further supported in the literature with publications describing reduction in distal catheter malposition with LA. Reference Schucht, Banz and Trochsler6,Reference Alyeldien, Jung, Lienert, Scholz and Petridis11,Reference Bani, Telker, Hassler and Grundlach12 Incisional hernia risk was the only other complication respondents thought LA would appreciably reduce the risk for (Table 2). There was no consensus on whether LA for revision VP shunt surgery was superior to mini-laparotomy, with many suggesting in the free-form section that it was case-dependent (relating to patient body mass index, hostility of the abdomen and history of abdominal surgery) (Figure 3). Visceral injury was the most divisive complication in both round one and round two. One quarter of respondents thought LA would have no impact on visceral injury risk, while one quarter thought it would reduce the risk by >50% (Table 2). Overall, the relationship between what is thought to represent the most common complications and which complications are perceived to have the greatest likelihood to benefit from the LA approach is mismatched. This puts the assessment of Canadian neurosurgeons somewhat at odds with several of the theoretical and published benefits of LA, and may explain in part why standardization of the LA approach has not occurred in Canada thus far. Further rationale for skepticism of the LA approach may also include uncertainty based on inadequate published evidence, which was noted by some respondents here in the free-form sections as well as in critique of the literature. Reference Abdelmageed, Sarkar, Shlobin, Davila and Potts15
Figure 3. Summary of round 2 responses detailing Q1) perceived barriers to laparoscopic assistance, Q5) utility of laparoscopic assistance in revision VP shunt procedures and Q8) complications perceived lead to increased hospital length of stay. Other responses to Q1) included “no barriers,” and in Q8 included) pre-existing conditions and poor support at home.
Limitations of the study include its cross-sectional nature, the number of overall respondents and the limited representation of the overall Canadian neurosurgical culture based on number of respondents per center. Furthermore, as this is a survey, the responses are expert opinion only and so may be biased by individual experience and philosophy. Although we did achieve representation from most provinces with neurosurgical services performing VP shunts, in several cases, there was only 1 respondent per center. As such, there could be biases based on individual experience and preference (either positive or negative) with respect to the role and value of LA. However, the objective of the study was to understand and highlight both agreement and disagreement within the Canadian community on these issues, which we have captured in these data.
Conclusions
In 2024, practicing Canadian neurosurgeons do not commonly encounter barriers to LA in VP shunt surgery beyond personal preference. However, there was no consensus on whether LA is generally superior to the traditional mini-laparotomy approach. Despite this, there was consensus that general attitudes to LA in VP shunt surgery are either positive or neutral amongst Canadian neurosurgeons. There was also general agreement that infection, distal catheter obstruction and proximal catheter obstruction are the most consistent post-operative complications in VP shunt surgery in Canada, with each carrying an estimated risk of up to 10% per surgery. Participants aligned with the literature in recognizing that the LA approach may reduce the risk of distal catheter malposition but does not significantly impact infection rates or other catheter-related complications. Contrary to previous research, participants did not believe that LA would lower the risk of distal catheter obstruction. Additionally, more than half of respondents considered patient comorbidities to be a greater factor in prolonged hospital stays than direct post-operative complications.
While there was no consistent specific endorsement for the LA approach identified here, there were few negative opinions expressed. This highlights an interest and opportunity for this approach to progress, and that Canadian neurosurgeons are largely open to the idea of bringing this into their practice if evidence supports it. Given the lack of consensus within the Canadian neurosurgical community regarding the role of LA in VP shunt placement to date, a multi-center randomized controlled trial would be valuable in clarifying its efficacy in this patient population, as none have been published to date.
Supplementary material
The Supplementary Material for this article can be found at https://doi.org/10.1017/cjn.2025.10433.
Acknowledgments
None.
Author contributions
JMH and MJK study conceptualization and design. JMH prepared the paper and supporting material. AB, SH, MAR, AM, MMC and MJK reviewed the article and made corrections. JMH, AB, SH, MAR, AM and NC collected data at their respective institutions.
Funding statement
No funding was obtained for the completion of this study.
Competing interests
None.
Open access
Target article
Practice Patterns of Canadian Neurosurgeons in Laparoscopic-Assisted Placement of Ventriculoperitoneal Shunts
Related commentaries (1)
Reviewer Comment on Heppner et al. “Practice Patterns of Canadian Neurosurgeons in Laparoscopic-Assisted Placement of Ventriculoperitoneal Shunts”