Computer assisted stereotactic placement of Ommaya reservoirs for delivery of chemotherapeutic agents in cancer patients

Placement of Ommaya Reservoirs Using Electromagnetic Neuronavigation and Neuroendoscopy: A Retrospective Study with Cost-Benefit Analysis

BACKGROUND

Placement of intraventricular catheters in oncology patients is associated with high complication rates. Placing Ommaya reservoirs with the zero-error precision protocol (ZEPP), a combination of neuronavigation (AxiEM stereotactic navigation) and direct verification of catheter tip placement with a flexible neuroendoscope, is associated with decreased complication rates as a result of increased catheter placement accuracy. However, the ZEPP costs more than traditional methods of catheter placement, and the question of whether this increased accuracy with the ZEPP is cost-effective is unknown.

METHODS

We performed a single-center retrospective chart review of 50 consecutive ommaya reservoir patient placements between 2010 and 2017. Twenty-five ventricular catheters were placed using the ZEPP protocol, and 25 ventricular catheters were placed using only AxiEM stealth navigation. Postoperative catheter accuracy and complication rates were assessed. A cost-benefit analysis was then conducted to determine if the overall cost for placing Ommaya reservoirs with the ZEPP was effective compared with the alternative method of using neuronavigation alone.

RESULTS

In the non-ZEPP cohort, 10 of 25 catheters were placed within the optimal location compared with 25 of 25 catheters placed in the ZEPP cohort. Three complications occurred in the non-ZEPP cohort: 2 malpositioned catheters required surgical revision and 1 catheter-related hemorrhage resulted in a prolonged stay in the intensive care unit. No complications occurred in the ZEPP cohort. A cost-benefit analysis showed $4784 savings per patient with ZEPP utilization because of the high complication-associated costs.

CONCLUSIONS

Implementation of the ZEPP for verifying ventricular catheter placement in Ommaya reservoirs improved catheter tip accuracy, resulted in lower complication rates, and was more cost-effective when compared with the non-ZEPP cohort, which used only neuronavigation. The ZEPP can be used for ventricular shunt catheter placement to decrease complications and verify catheter tip accuracy in Ommaya or standard ventriculoperitoneal shunts.

Image Guidance for Placement of Ommaya Reservoirs: Comparison of Fluoroscopy and Frameless Stereotactic Navigation in 145 Patients

OBJECTIVE

Ommaya reservoirs are used for administration of intrathecal chemotherapy and cerebrospinal fluid sampling. Ventricular catheter placement for these purposes requires a high degree of accuracy. Various options exist to optimize catheter placement. We analyze a cohort of patients receiving catheters using 2 different technologies.

METHODS

Retrospective chart review was performed on patients undergoing Ommaya reservoir placement between 2011 and 2014. Most procedures were assisted by either frameless stereotactic neuronavigation or fluoroscopic guidance with pneumoencephalogram. Catheter accuracy, revision rates, perioperative complications, and operative time were measured. Preoperative similarities and differences in diagnosis, demographics, and ventricular size were also recorded to avoid a biased assessment of our results.

RESULTS

One-hundred and forty-five patients were included, 57 using fluoroscopic guidance and 88 using frameless stereotaxy. Common diagnoses in both groups were lymphoma and leptomeningeal disease. Qualitative measures of catheter placement accuracy showed no significant difference between the 2 groups. Proximity to the foramen of Monro favored fluoroscopy by a small margin (8.6 mm vs. 10.2 mm, P = 0.03). Overall revision rates were not significantly different between the groups (3.5% vs. 4.5%, P = 1.00). Early surgical complications occurred in 6.8% of the frameless stereotaxy group and 1.8% of the fluoroscopy group (P = 0.25).

CONCLUSIONS

Ommaya reservoirs can be placed accurately using different methods. Although there are slight differences between fluoroscopy and frameless stereotaxy in quantitative accuracy and procedure time, there is no significant advantage of 1 method over the other when evaluating revision or complication rates. Technique familiarity and surgeon preference may dictate the preferred procedure.

Frameless Stereotactic Ommaya Reservoir Placement: Efficacy and Complication Comparison with Frame-Based Technique

BACKGROUND

Ommaya reservoirs are ventricular access devices used primarily for the administration of intrathecal antineoplastic chemotherapy. In patients with low or normal ventricular volume, stereotaxy can improve accuracy of catheter placement with minimal morbidity. Frameless stereotaxy has become an increasingly popular alternative to frame-based stereotaxy. Relative rates of successful catheter placement between these two techniques are not described in the literature.

OBJECTIVES

To compare a large series of frameless to frame-based stereotactic catheter placements for Ommaya reservoirs, with an aim to compare accuracy and complication rate between the two procedures.

METHODS

A consecutive series of 41 frame-based and 68 frameless Ommaya reservoir placement procedures performed at our institution from 1998 to 2013 was reviewed. Patient demographics, operative accuracy and complication rates for the two techniques were compared.

RESULTS

Characteristics of the two groups were similar in diagnoses, age and other related factors. Comparison of frameless to frame-based stereotactic Ommaya catheter placement did not show significant differences in accuracy of placement, overall morbidity or mortality, or in any subcategory of complications.

CONCLUSIONS

These findings suggest that frameless stereotactic Ommaya reservoir placement is as safe and accurate as the frame-based technique.

Modified stereotactic insertion of the Ommaya reservoir. Technical note

Ommaya reservoirs are used primarily for the repeated injection of intrathecal chemotherapy for leptomeningeal metastasis from hematopoietic and solid malignancies. Insertion of this device in a relatively large nondisplaced ventricle is not a difficult task, but challenges arise when the ventricle is small and/or displaced. Different techniques have been developed to overcome this difficulty, most of which include the use of stereotactic frames. Further improvements would be beneficial. The technique described in this paper depends on a stereotactic frame; however, the modification proposed by the authors removes the arc system from the surgical field before the actual surgical procedure is begun. Removal of the arc improves access to the surgical field as well as preparation and draping of the surgical site and minimizes potential breaks in sterile technique, which ultimately reduces the incidence of infection. A twist-drill hole along the path of the chosen trajectory becomes an external guide for the ventricular catheter. The technique is easy, user friendly, and results in an unencumbered sterile field and reliable cannulation of small ventricles. A simple stereotactic technique for Ommaya reservoir insertion has been described. It should lower the chance of infection in this group of patients, most of whom have suppressed immune systems.

Stereotactic insertion of an ommaya reservoir: technical note

BACKGROUND

Stereotactic insertion of catheters into deep-seated tumors or developmental cysts is easily accomplished, but connecting the catheter to an Ommaya reservoir while maintaining catheter position can be difficult. We describe a technique for easy placement of a catheter-Ommaya reservoir construct with one pass.

METHODS

Standard stereotactic imaging is performed. The distance from the outer table of the skull to the target point is measured. A catheter-Ommaya reservoir construct is assembled to this length and directed to the target position with a standard Cosman-Robert-Wells (CRW) stereotactic frame.

RESULTS

Use of this technique placed catheters into tumor or developmental cysts accurately and with no surgical complications in 12 patients.

CONCLUSIONS

This technique is simple, safe, reliable, and requires no special equipment. It avoids the risk of dislodging the catheter when it is being connected to the Ommaya reservoir, reducing the chances of cyst leakage and collapse.