Headbutting against the floor and the wall. Screaming in pain. Desperate. This is how Josep Riba, a 55-year-old from Catalonia, spent his daily episodes of cluster headaches. From the age of 21, those intense headaches appeared six, seven or eight times a day, each lasting up to two hours. “They were like continuous punctures to my face and brain. I would end up lying on the floor like a cockroach. I was screaming, I wanted to die. It was impossible to sleep or to live,” he recalls of the worst episodes. Cluster headaches are rare, and their origin is unknown. According to neurologists, though, their pain can incapacitate patients and lead them to profound despair, even suicidal thoughts. Existing treatments, from high-dose corticosteroids to Botox and lithium, do not always work. In the most extreme treatment-resistant cases, such as Riba’s, only one option remains: placing electrodes in the brain to try to control the intensity of the pain. “Now, after the operation, at least I no longer throw myself on the floor or scream,” he says, resigned. He suffers half a dozen headaches every night, each lasting about 20 minutes.
When the American doctor Bayard T. Norton named this strange headache in 1939, he defined it as “a pain so severe that patients should be monitored for risk of committing suicide.” It was colloquially named “the suicide headache.” It is a serious condition, explains Dr. Robert Belvís, head of the Headache Unit at Hospital Sant Pau in Barcelona: “They call it that because of the risk involved. The suicide attempts are not so common, but suicidal behavior is. There are patients who say that they want to throw themselves off of something, but they do not do it.” Patients suffering from this ailment are supervised by suicide prevention units of psychiatric institutions.
No one knows what causes cluster headaches, which affect one in 1,000 people and three times as many men as women. Belvís points out that no associated genes have been found, and the condition does not seem to be hereditary. When a patient suffers an attack, the hypothalamus is the first region of the brain to suffer, but the reasons are unknown: “The genes of the hypothalamus are being looked at, because substances called orexins are produced there. They have looked to see if there was any kind of relationship, but nothing has been found”. In addition, it is difficult to diagnose in emergencies or among neurologists: in Spain, diagnoses take an average of four years, compared to six in the United States and 11 in Norway, says Belvís.
Each patient is different. A third of them usually have attacks seasonally, especially in spring or autumn, but the rest suffer pain randomly, without a defined pattern. All of them, in any case, begin with episodic pain of severe or very severe intensity (migraines, in comparison, are moderate or severe). “One day, you start having a cluster of several pain attacks that last from two weeks to three months. Visually, it is as if you had punched the patient in the eye. He cries, turns red, the eyelid swells, the forehead swells and mucus and tears are produced only on that side. The patient feels that his ear is clogged,” Belvís explains. These symptoms are joined by episodes of agitation, the neurologist adds: “There are people who start hitting themselves, who self-injure, to avoid having that pain. Patients often say that it is as if their eye was ripped out. It is a very serious pain.”
The therapeutic arsenal is extensive, but it does not always work. For crises, doctors use triptans, the most aggressive family of anti-migraine drugs, and administer 100% oxygen for half an hour (in attacks of asthma or bronchitis, 28% is used for several hours). “Oxygen is a vasoconstrictor and prevents the production of nitric oxide, which is one of the molecules that produces pain in the brain,” says the neurologist. High-dose cortisone is also administered. Some drugs are used to control the intensity and periodicity of the attacks, such as lithium (an aggressive antipsychotic that is only used for this condition and bipolar disorder), antiepileptic drugs, Botox injections and a monoclonal antibody used for migraines.
Ten percent of patients do not respond to any pharmacological treatments and require surgery. The least invasive operation is applying radiofrequency to the sphenopalatine ganglion, which enters the nerve through the mouth, heats it and removes the pain. If that doesn’t work, neurosurgeons opt to incorporate an occipital nerve stimulator, which requires a more complex intervention. Some patients with chronic cluster headaches do not respond, and the only remaining treatment option is deep brain stimulation.
The scientific literature describes only 94 cases that have undergone this operation, explains Belvís. The Hospital Sant Pau is known for these surgical procedures. They have done 14 and now conduct two or three per year, says Rodrigo Rodríguez, neurosurgeon and deputy and coordinator of the Tactical Functional Unit at Hospital Sant Pau. “The technique consists of the introduction of an electrode in an area of the brain that does not respond correctly [in this case, the hypothalamus], in order to create an electrical change that will affect the connectivity and electrical flow of different brain structures to normalize brain function,” he explains. The treatment is used more commonly for other ailments, including Parkinson’s.
After this intervention, 80% of patients show clinical improvement. As in the case of Riba, the headaches do not completely vanish, but the attacks are reduced by up to 50% and are less intense, says Rodríguez, a neurosurgeon at Sant Pau who is also in charge of these interventions. The operation, adds the specialist, is very safe and rarely implies complications. He explains that “the operation begins before entering the operating room.” “There is a lot of pre-planning, in which we analyze the pain circuit and see which networks are affected. This part of planning is fundamental because it gives security to the procedure inside the operating room.”
When the neurosurgeons proceed to drill holes in the skull to place the electrodes at the base of the hypothalamus, they go for a straight shot. The prior planning allows them to map their exact route. With the help of a kind of crown that marks the spatial coordinates of the point of intervention, they insert the electrical devices. There is hardly any margin for error, but the surgeons do an intraoperative CT scan to confirm that the electrodes are correctly placed.
In most cases, the number of headaches or the intensity of the pain is reduced. There is a significant change from before the operation. However, the specialists admit, there is always a percentage of patients who do not respond to the surgery. Alternatives are limited: try combinations of treatments and drugs that reduce headaches, support the patients and continue researching to find new options. Much remains to be discovered about this disease.