Surgery poses the lowest risk when it is performed before an aneurysm ruptures. The patient’s condition, the size and location of the aneurysm, and other factors determine the risk of surgery. Your doctor will discuss the risks and benefits of surgery with you and your family and answer any questions you may have. 

Clipping is an open surgical procedure to seal off the aneurysm neck and, thus, prevent blood from entering the aneurysm, which obliterates it. Clipping of brain aneurysms has been available longer than endovascular therapy, and has excellent long-term results. In recent years, titanium clips have generally been used. These are MRI compatible and they will not set off alarms at metal detectors. 

The Procedure 
A patient undergoing aneurysm surgery seldom requires blood replacement. If necessary, blood from the blood bank is used. You can also donate your own blood before the procedure, or have family members donate if you prefer. 

This surgery is done under general anesthesia, so patients meet with an anesthesiologist before the procedure and are asked questions about their medical history. 

A team of doctors, led by a neurosurgeon, performs the clipping procedure. This is an open surgery, which means the skull is cut and opened, and microsurgery is performed. Part of the preparation for this surgery may include shaving a section of the hair on your head. 

The neurosurgeon makes an incision behind the hairline or on the back of the head, depending on the location of the aneurysm. From there a section of bone, or bone  plate, is removed (craniotomy) from the skull to expose the brain tissue. 

The neurosurgeon approaches the aneurysm in the opening between the skull and the brain, but does not go through brain tissue. Under a microscope, the aneurysm is carefully separated from the normal blood vessels and the brain, so the neurosurgeon can see it and properly treat it. 

The aneurysm is then clipped with a device that resembles a tiny clothespin. With the clip in place, the aneurysm is totally sealed off, and no more blood can enter it. The bone plate is then secured into place and the wound is closed. Aneurysms that are quite large or involve a large section of the blood vessel may require special procedures, such as putting clips on either side of the aneurysm or making a bypass around the aneurysm. 

After the surgery, you will wake up somewhat cold and slightly dizzy, and amazed that it is all over. You will need to do breathing exercises. You may experience nausea and a sore throat. 

What will surprise you is how little you remember of the day of the operation, and how well you feel the next day. 

After Treatment 
In most cases you will stay at least one night in the Neurological/Neurosurgical Intensive Care Unit (NICU). The stay in the NICU will be longer for patients with a ruptured aneurysm to closely monitor for the development of vasospasm

Once transferred to a hospital room outside of the NICU, most patients are up within a few days to a week. Patients treated for an unruptured aneurysm will leave the hospital within a few days, while patients treated for a ruptured aneurysm will usually leave the hospital within two weeks. However, if complications arise, the stay will be longer. 

If all goes well, recuperation at home takes about a month to six weeks. Your doctor will clearly define your limitations before you leave the hospital.