Comparative Study of the Effectiveness of Lumboperitoneal and Ventriculoperitoneal Shunting with Neuronavigation in the Treatment of Idiopathic Intracranial Hypertension
Keywords: Idiopathic intracranial hypertension, lumboperitoneal shunt, neuronavigation, pseudotumor cerebri, ventricle-peritoneal shunt
Idiopathic intracranial hypertension (IIH) is a disorder characterized by increased intracranial pressure with its associated signs and symptoms (mainly headache and visual loss) in alert and oriented patients with no lesions detected after neuroimaging and normal cerebrospinal fluid (CSF) analysis findings except for increased open pressure.
The general incidence of IIH is 0.9 per 100, 000 inhabitants/year, and is higher in young females (15–44 years old) who have an incidence of 3 per 100, 000 inhabitants/year.
The initial treatment of choice for IIH is conservative and includes weight loss and conservative treatment. Advanced cases with significant visual loss and/or progressive IIH may be refractory to conservative measures alone, with the drugs of choice in such cases being acetazolamide or topiramate. Such advanced cases occur in 10% to 20% of IIH patients and, if left untreated, may progress at highly variable rates (weeks–years) to permanent blindness via optic nerve atrophy. Therefore, timely referral to surgical subspecialists is recommended in the case of advanced IIH cases.
Modern surgical treatments typically involve the placement of lumboperitoneal (LP), or ventriculoperitoneal (VP) shunts.,
However, treatment of IIH using VP or LP shunts has been consistently associated with significant complication rates, which are more frequently related to proximal catheter infection and the need for frequent revision.
Neuronavigation has been shown to improve the results of VP shunt in IIH by reducing the need for revisions due to wrong positioning of the proximal catheter. The lumbar puncture (used in the LP shunt) is made blindly without the need for navigation systems.
There have been previous studies comparing both techniques with current recommendations indicating VPS as the preferred procedure but also recommending LP as an alternative, some authors suggest that VPS has lower revision rates, but there is no definition in the literature and it is important to publish the experience of large centers to help in future consensuses. In this study, we aimed to contribute to the current knowledge using a new series of cases comparing LP and VPS with neuronavigation, which has not been explored before by previous studies.
We obtained data from medical records of 46 patients who underwent VP and LP shunt between January 2007 and December 2017. All the patients included in the study satisfied the modified Dandy criteria, listed below:
Patient demographics, neurological status, and ophthalmological examination at presentation and during hospitalization, as well as operative records, were examined to determine initial shunt placement and any following revisions. Patients operated by more than one surgeon were not separated during statistical analysis since the surgeons were found in the same center and formed a homogeneous group with a similar formation. The choice of diversion site BMI equal to or greater than 37 and the presence or suspected of Chiari syndrome and tonsillar ectopy were contraindicated to LPS, these patients always performed VPS, for all others the procedure of choice was LP as first procedure however sometimes the material was unavailable and in that case, it was done VPS.
The subjects were divided into two groups according to the initial procedure performed on them. Group I comprised 17 patients that had undergone VPS with neuronavigation as the initial procedure while group II comprised 29 patients who had undergone LPS as the initial procedure (conventionally LPS requires no navigation).
The minimum follow-up was 1 year (range 12 months to 60 months).
The differences between the two groups were compared using the Chi-square test. The variables in this study were the number of procedures (revision rates), hospitalization time, complications rates, and surgical and anesthetic time.
The patients cross over from one procedure to another, which depended on clinical conditions such as complication or failure of the shunt and other surgical complications, were identified.
A total of 46 patients were used as subjects. Group I comprised 17 patients that had undergone VPS with neuronavigation, 16 of whom were female. Group II comprised 29 patients that have undergone LPS, 26 of whom were female [Table 1]. In the LPS group, 4 patients (14%) underwent one procedure (no need for revision), 13 underwent two procedures (one revision), 3 underwent three procedures (two revisions), and 9 underwent four or more procedures (three or more revisions). In the VPS group 10 patients (59%) underwent one procedure (no need for revision), 4 underwent two procedures (one revision), 2 underwent three procedures (two revisions), and 1 underwent four or more procedures [Figure 1], [Figure 2], [Figure 3]. There was no statistically significant difference between the two groups (P = 0.85).
Number values represent several patients.
Infection: ventriculitis or infection of any surgical site.
Wrong position: proximal or distal catheter poorly positioned on image examination.
Malfunction: hyper drainage or hypo drainage.
We reviewed a series of IIH cases to evaluate the efficacy complications of VPS with neuronavigation and LPS conducted in patients from January 2007 to December 2017.
We recruited a total of 46 patients, 27 of whom underwent LPS [Figure 4]a and [Figure 4]b while 17 underwent VPS with neuronavigation [Figure 5]a and [Figure 5]b. The number of reoperations was higher in LPS and the number of patients without reoperations was higher in VPS group (59% VPS and 14% LPS) but the rate of complication was similar between the two groups, at the in this study, the epidemiologic profile of the sample was similar to that of a previous study conducted in Sheffield, the UK that revealed a female/male proportion of 15/1.,,,,,,,,,,,, A study conducted in 1990 revealed a female/male proportion of 19/1.
Surgical treatment is rarely necessary for IIH. The two main surgical options are VPS and LPS; however, they are often associated with complications mainly related to ventricular puncture difficulty for VPS. This has led to the need for means to guide the puncture process, in this case, neuronavigation, which improves the accuracy of the puncture, and thus reducing the complications. A previous series of cases with stereotactic placement reported that the rate of revision due to proximal malfunction was 2.9%, which is similar to our series.
In currently the largest series comparing VPS and LPS, the revision rates were reported to be 3.7% and 7%, respectively. An important factor that affected the results of this study was the greater training of the surgeons of this center in VPS than LPS, as well as the greater accuracy for identification and early resolution of complications in VPS. The same reason justifies the observed differences in the surgical time between the two procedures. Although our study did not show a statistically significant difference between the two groups, we consider neuronavigation as important in improving the results and reducing the cost of hospitalization as demonstrate by previous retrospective studies.,
Our results suggest that the choice of shunt procedure can change the patient's prognosis and that VPS in our series was better. Other previous studies have suggested that the rates of complications in LPS are intolerable.,
The main limitation of this study is that the patients were not randomized and that they were placed either group based on the preference of the surgeons, or in some cases, the availability of equipment.
From this study, we can see that LPS is suitable as an initial procedure; however, our results show that not an ideal choice in case of complications. Although several authors have shown that when adding ventricular puncture navigation or exteriotaxis systems, the performance of VPS was greatly improved, our results show that LPS is a more viable alternative with a greater chance of not having to reoperation.
We propose that LPS be used as an initial treatment after which VPS should be adopted in case of reoperations., This could be a new surgical approach model for IHH because some centers do VPS and other LPS but this combination of the two could optimize the results.
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Conflicts of interest
There are no conflicts of interest.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]