Ommaya Reservoir

What is an Ommaya Reservoir?

An “Ommaya reservoir” refers to a surgically implanted device used for the aspiration of cerebrospinal fluid or for the administration of drugs into the cerebrospinal fluid. The Ommaya reservoir also known as an Ommaya shunt ¹.

This device consists of a catheter in one ventricle attached to a reservoir implanted under the skin on the head. The lateral ventricle of the brain produces cerebrospinal fluid, and an Ommaya reservoir gains direct access to the CSF. The patient will feel the reservoir under his scalp by touching the elevated area.

This device will help to treat brain tumors, leukemia, or leptomeningeal diseases by administration of intrathecal medications to your cerebrospinal fluid (CSF). This also used to drain excessive CSF from the brain and allows your doctor to take samples of your CSF easily. A famous Pakistani neurosurgeon, Ayub K. Ommaya, invented this device in 1963.

How does an Ommaya reservoir procedure work?

The entire operation requires an expert neurosurgeon, an anesthesiologist, and a surgical assistant to perform successfully. The surgery itself will require about 30 minutes, but the entire process may take about an hour. The process includes ²:

• Anesthesiologist will give general anesthesia to fall asleep during the operation so you do not feel any pain.
• Your surgeon will shave the surgical site in your head to implant the Ommaya reservoir.
• Nurses will monitor the vital signs of the patient during the operation.
• Surgeon will give a small incision in your scalp to insert the reservoir.
• Your surgeon will place the catheter into a ventricle through a small hole in your skull.
• Your surgeon will close the incision with staples or stitches.
• Surgeon will cover the surgical site by a bandage.
• Perform a CT scan of your head to ensure proper placement of the Ommaya reservoir.
• Surgeons strictly advised not to eat anything at least 8 hours prior to the operation.

The entire implantation procedure considered safe, but during any operations, complications can arise. These include ³:

• Infection in the brain tissue
• Excessive loss of blood in the brain
• Formation of hematoma in the brain
• Partial loss of brain function

A complete course of antibiotics may require to prevent any post-surgical infections. Staphylococcus aureus (56%) and Propionibacterium acnes (24%) considered as the most frequent pathogens to cause infections after surgery ⁴. Talk to your doctor about any queries regarding your post-operative complications.

What does the recovery from an Ommaya reservoir procedure look like?

Your surgeon may remove the stitch from the incision area after 2 weeks. Ommaya reservoir operation usually takes 6 weeks to heal completely. The effectiveness of the Ommaya reservoir reaches about 100%. Your surgeon may advise to keep the surgical area dry and clean to avoid any infection. The sign of infection includes ⁵:

• Fever
• Headaches
• Vomiting
• Dizziness
• Stiffness in the neck
• Fatigue
• Redness near the incision site
• Swelling in the incision site
• Oozing near the incision site
• Pus in the incision site

After complete healing, you can start your normal activities. Ommaya reservoirs usually require no care or maintenance. Your surgeon will do a further CT scan or MRI scan within a day after your surgery to confirm if the device placed correctly.

References

1. Lane J, Zacharia BE. Endoscopic-Assisted Ommaya Reservoir Placement: Technical Note. Cureus. 2017;9(7). doi:10.7759/cureus.1490
2. Peyrl A, Chocholous M, Azizi AA, Czech T, Dorfer C, Mitteregger D, Gojo J, Minichmayr E, Slavc I. Safety of Ommaya reservoirs in children with brain tumors: A 20-year experience with 5472 intraventricular drug administrations in 98 patients. Journal of Neuro-Oncology. 2014;120(1):139–145. doi:10.1007/s11060-014-1531-1
3. Magill ST, Choy W, Nguyen MP, McDermott MW. Ommaya Reservoir Insertion: A Technical Note. Cureus. 2020;12(4). doi:10.7759/cureus.7731
4. Mead PA, Safdieh JE, Nizza P, Tuma S, Sepkowitz KA. Ommaya reservoir infections: A 16-year retrospective analysis. Journal of Infection. 2014;68(3):225–230. http://dx.doi.org/10.1016/j.jinf.2013.11.014. doi:10.1016/j.jinf.2013.11.014
5. Wang A, Tenner MS, Schmidt MH, Bowers C. Placement of Ommaya Reservoirs Using Electromagnetic Neuronavigation and Neuroendoscopy: A Retrospective Study with Cost-Benefit Analysis. World Neurosurgery. 2019;122:e723–e728. https://doi.org/10.1016/j.wneu.2018.10.127. doi:10.1016/j.wneu.2018.10.127