Sometimes medications alone are not effective enough to relieve the symptoms of depression. There are also times when people are unable to take medications due to conditions such as pregnancy. In these cases, other medical therapies may be of help. These therapies include:
- electroconvulsive therapy (ECT)
- light therapy
- vagal nerve stimulation (VNS),
- transcranial magnetic stimulation (TMS)
- deep brain stimulation (DBS).
Electroconvulsive Therapy (ECT)
Electroconvulsive Therapy, or ECT, is perhaps the most successful non-medication medical therapy for depression. This is often referred to as "shock therapy." It involves passing an electric current through the brain to create an artificial seizure. ECT is typically used for people with severe depression that has not responded to other treatments and/or for people requiring non-medication treatment of depression.
The ECT procedure takes about 10 or 15 minutes, with an additional 30-45 minutes for preparation and recovery. It can be performed either during a hospital stay or as an outpatient procedure. ECT requires brief general anesthesia (i.e., the person is asleep during the procedure). Prior to the procedure, patients are given muscle relaxants to prevent damage from convulsions, which occur during the seizure. An electrode (or electrodes) is placed on the side or the front of the person's forehead. Then a short, controlled electrical current is passed through the brain.
Most patients receive 6 to 12 ECT treatments over the course of several weeks. Usually, treatment is administered two to three times a week until symptoms improve. Then, maintenance treatments will be administered at less frequent intervals. Though the procedure has the side effect of causing temporary short term-memory loss and concentration problems, it can work very well when other treatments fail.
Historically, ECT was thought of as a barbaric, inhumane treatment. This is not at all the case today. The modern method is well-researched and regulated. It is quite safe and provides very fast relief from forms of depression that will not otherwise respond to treatment. Because there are no body effects, it may be the safest treatment option for pregnant women or nursing mothers suffering from depression.
It is not clear exactly how ECT helps people with depression. Many neurochemical and neuron aspects of brain functioning are altered during and after seizure activity. It is thought that when ECT is administered on a regular basis, these changes build upon one another, somehow reducing depression. In addition, ECT increases neuron growth in the brain, which may lead to relief from depressive symptoms.
Light Therapy (Phototherapy)
Phototherapy involves controlled exposure to intense light under specified conditions. This therapy is most effective for people who suffer from major depressive disorder with a seasonal pattern. This type of depression seems related to seasonal variations in sunlight. It is not entirely clear how phototherapy provides its antidepressant effects. Researchers think that the light entering the eyes influences the hypothalamus in the brain. This may alter melatonin production. Melatonin is a hormone product of the brain's pineal gland that is built out of serotonin. Changing the melatonin production in turn affects the body's circadian and seasonal rhythms. Phototherapy is an inexpensive technique that can be done at home or at the office. There are no major side effects associated with its use.
Phototherapy sessions require a specialized light box with fluorescent bulbs and a diffusing screen. The light produced by the box is comparable to outdoor light just after sunrise or just before sunset. It is an intensity that is at least five times greater than ordinary indoor light. During a session, a person sits near a light box placed on a table. The person keeps their eyes open, but does not look directly at the light (i.e., you can read during the session). Researchers recommend phototherapy sessions lasting between 15 minutes and two hours, once a day, in the morning.
Recent research suggests that naturalistic dawn simulation and high-density negative air ionization delivered during the final hours of sleep may be effective alternatives to light therapy for people who suffer from this seasonal type of major depressive disorder.
Vagal Nerve Stimulation (VNS)
The vagus nerve emerges from the base of the brain and travels down the neck into the chest and abdomen. This long nerve regulates a number of vital body functions such as digestion and heart function. In addition, the vagus nerve seems to play a role in regulating mood. The Food and Drug Administration approved vagal nerve stimulation or VNS for treating people with depression who have not responded to other therapies.
Stimulation of the vagus nerve is achieved by surgically implanting a small electrical pulse generator the size of a pocket watch in the upper-left side of the chest. Tiny wires, which transmit intermittent electrical pulses, are routed under the skin and up to the neck, where they wrap around the vagus nerve. Once the pulse generator is in place, the electrical pulses must be monitored and modified periodically by a neurologist in his or her office. This doctor controls how long pulses last and how frequently pulses are sent to the vagus nerve, depending on a person's response to therapy. The most common side effects of VNS include hoarseness and cough during stimulation. Although this treatment is effective, it is not instant. It takes several months to effect depressive symptoms.
Transcranial Magnetic Stimulation (TMS)
In transcranial magnetic stimulation or TMS, a magnetic field generator or "coil" is placed near the head. This generator produces small electric currents in the region of the brain just under the coil. This magnetic field is thought to stimulate neurons within the brain. Transcranial magnetic stimulation is non-invasive. It is usually done in an outpatient setting (not in a hospital) and takes about 20 to 30 minutes. The patient is awake and alert during the procedure. It is somewhat similar to ECT in that the brain is stimulated with both techniques. However, ECT requires the passage of electrical current through the brain, while TMS involves the passage of magnetic waves through the brain.
TMS does not interfere with people's memory or concentration in the way that ECT does. However, the TMS procedure does on occasion cause fainting or a seizure to occur. Apart from these risks, there are no significant side effects associated with the procedure. Treatment-resistant depression has been shown to improve with TMS.
Deep Brain Stimulation (DBS)
Deep brain stimulation (DBS) is an experimental surgical treatment involving the implantation of a medical device that sends electrical impulses to specific parts of the brain. DBS has been approved for treating:
- tremor - a disease where parts of the body, usually the hands, shake when someone is intentionally moving)
- dystonia - a condition where muscle contractions cause twisting and repetitive movements or abnormal postures
- Parkinson's Disease.
DBS has also shown some promise in helping people with depression that is resistant to other treatments.
The pacemaker or stimulator that controls DBS is placed in specific areas of a person's brain. This location is mapped out ahead of time using imaging technology such as a CT scan or MRI. It is implanted during a surgical procedure where the patient is anesthetized (i.e., feels no pain), but is awake. The device is then set to provide optimal amounts of stimulation for each person. After approximately 3 to 5 years, the brain pacemaker must be replaced, because the batteries wear out over time.
Deep brain stimulation is not without potential side effects. These can include:
- apathy (lack of emotions)
- compulsive gambling
- cognitive dysfunction (problems with remembering words, paying attention, and learning new material)
- suicidal behavior
- personality changes
- brain swelling or bleeding.
However, the side effects may be temporary and related to the placement and initial setting of the pacemaker.
A March 2010 systematic review found that about half the patients did show dramatic improvement and that negative events were generally not serious. In the United States, deep brain stimulation is available on an experimental basis only. It is available on a regular basis in Australia.