Once it has been determined you are eligible for deep brain stimulation by our team, you will have time to ask questions and become familiar with the process. If you choose to proceed with the surgery, a surgery date will then be scheduled. We will discuss with your neurologist and primary care physician to ensure they are in agreement with you proceeding with this surgery. We will provide you with pre-operative instructions and further education on what the pre-, intra-, and post-operative course will entail. Pre-op testing will be done which may include a MRI, History & Physical, labs, EKG, x-rays, and any other patient specific pre-operative tests.
In some cases in order to have a better understanding of a patient’s cognitive function, we will obtain a formal neuropsychological evaluation.
We are here to support you through this process and make it as easy as possible. We are on your team!
There is a specific Neurosurgical DBS team that will be with you throughout your procedure. You will check in with preadmissions and from there they will take you to the pre-op area. Here, nurses and doctors will begin to prepare you for surgery. This will include an IV being started and they may choose to draw more labs at this time. An anesthesiologist will come speak with you and tell you about their role. Before you are taken to the operating room, Dr. Sani will attach a rigid frame to your head before to you having an MRI of your brain before surgery. The frame is a special piece of equipment the surgeon uses to determine the correct path to the target site in your brain. The MRI helps determine where the target is and where the leads will be placed.
Dr. Sani will review your MRI and begin mapping the anatomical target that is best used for your symptoms. In other words, he will locate the “hot spot” on your MRI and plan a map as to the exact path the lead will follow to reach the “hot spot” within the brain.
The operating room nurse and nurse practitioner will be at your side throughout the entire course of surgery. After the MRI is complete, you will be taken to the operating room and we will position you on the bed where you will assist us in what is the most comfortable position for you. You will then be given intravenous sedative and a Foley catheter may be placed in the bladder. The frame on your head is rigidly fixed to the operating table. A small area of hair on top of your head will be shaved and area will be washed. Once drapes are applied, additional frame components will be attached behind the surgical drape. After injecting local anesthetic to the scalp to make it completely numb, an incision is made on top of the head behind the hairline and a small opening (1.5 centimeters, about the size of a nickel) is made in the skull. At this point, all intravenous sedatives are turned off so that you are fully awake.
To maximize the precision of the surgery, we employ a "brain mapping" procedure as discussed above uses stereotactic techniques to locate the nucleus of interest. A microelectrode lead will be placed along the designated pre-planned track to the “hot spot,” or area of interest. Once Dr. Sani has the lead in place, we will perform microelectrode recording (MER). MER consists of recording brain cell activity in the region of the intended target (where the current lead is) to confirm that the anatomical location is correct. The brain cell recordings indicate when we are in the intended target area. At times, very fine adjustments of 1 or 2 millimeters may be made if the initial target/recordings are not exactly correct.
The brain mapping produces no sensation for you, but it is imperative that you remain calm, cooperative, and silent during the mapping. The brain's electrical signals are played on an audio monitor so that the surgical team can hear the signals and assess their pattern. The electronic equipment is fairly noisy, and the members of the surgical team often discuss the signals being obtained so as to be sure to interpret them correctly. Since each person’s brain is different, the mapping time varies from about 30 minutes to 2 hours for each side of the brain. The surgical team monitors your neurological status (such as strength, vision, and improvement of motor function) very frequently during the operation to make sure none of the work is causing adverse effects. Again, the operating room nurse and nurse practitioner will be at your side to support you through this.
When the correct target site is confirmed with the microelectrode, the permanent DBS electrode is inserted and tested for about 20 minutes - this is called microstimulation. The testing does not focus on relief of your pre-operative symptoms but rather on unwanted stimulation-induced side effects. Beneficial effects of stimulation may occur during microstimulation, however, they can take hours or days to develop, whereas any unwanted effects will be present immediately. For the testing, we deliberately turn the device up to a higher intensity than is normally used, in order to deliberately produce unwanted stimulation-induced side effects (such as tingling in the arm or leg, difficulty speaking, a pulling sensation in the tongue or face, or flashing lights). The sensations produced at high intensities of stimulation during this testing are experienced as strange but not painful. We thus confirm that the stimulation intensity needed to produce such effects is higher than the intensity normally used during long-term function of the device.
Once the permanent DBS electrode is inserted and tested, intravenous sedation is resumed and you will become very sleepy, the electrode is anchored to the skull with a plastic cap, and the scalp is closed with sutures. The head frame is removed and then you will receive a general anesthetic so that you are completely asleep for the placement of the pulse generator in the chest and the tunneling of the connector wire between the brain electrode and the pulse generator unit. This part of the procedure takes about 40 minutes.
When you awaken after surgery, you will notice that you will still have the IV in place and you will have special stockings on your legs. You will have plastic sleeves over your legs that will inflate and deflate to promote circulation. You may also still have a catheter tube in your bladder so that you will not need to get out of bed to urinate. The tube is usually removed the day after your surgery and then you will be able to ambulate to the bathroom. You will be watched carefully for the first 24-48 hours in either the ICU or on the neuro floor. You may have side effects from the swelling in your brain, including mild disorientation, sleepiness, or personality change that can last for 1-2 weeks.
The surgeon will then determine when the generator can be turned on and tested. Depending on how you are healing, it may be turned on right away or after you have healed (3-4weeks). To get the programming started we use a computer called a clinician programmer. It will then be set at the best level to provide maximum symptom relief, you may not notice a difference for a few hours after it is turned on. You may have to return to the clinic or your neurologist office if the neurostimulator needs adjusting over time.
This is just a general overview, and your case may have small differences. Our goal is to keep you well informed and up to date about what you can expect with DBS.