Unruptured brain aneurysm(Incidentally detected brain aneurysms)

Dr. Avinash KMMS, MRCS Ed(UK), Mch (KEM, Mumbai), FINR(Switzerland), FMINS(Germany),

• Interventional & Neurovascular surgeon and Stroke specialist, • Endoscopic Neuro and Spine surgeon, • Minimally invasive Neuro and Spine surgeon (FMINS).

mob: 9740866228, E mail: doc_avin@hotmail.com

Consultant Neurosurgeon and Neurointerventionist

Columbia Asia Hospital, Bangalore.

What is brain Aneurysm?A brain aneurysm, also referred to as a cerebral aneurysm or intracranial aneurysm (IA), is a weak bulging spot on the wall of a brain artery very much

like a thin balloon or weak spot on an inner tube. Over time, the blood flow within the artery pounds against the thinned portion of the wall and

aneurysms form silently from wear and tear on the arteries. As the artery wall becomes gradually thinner from the dilation, the blood flow causes the weakened wall to swell outward. This pressure may cause the aneurysm to

rupture and allow blood to escape into the space around the brain. A ruptured brain aneurysm commonly requires advanced surgical treatment

What are the symptoms of aneurysms?

1. Asymptomatic incidentally detected aneurysms2. Symptomatic unruptured aneurysms3. Ruptured aneurysms

Most brain aneurysms cause no symptoms and may only be discovered during tests for another, usually unrelated, condition(Asymptomatic incidentally detected aneurysms).

In other cases, an unruptured aneurysm will cause problems by pressing on areas in the brain. When this happens, the person may suffer from severe headaches, blurred vision, changes in speech, and neck pain, depending on what areas of the brain are affected and how bad the aneurysm is.

Symptoms of a ruptured brain aneurysm often come on suddenly. A sudden, severe headache that is different from past headaches.(worst headache of life)Neck pain.Nausea and vomiting.Sensitivity to light.Fainting or loss of consciousness.Seizures.

What are the risk factors for formation of aneurysm?

Modifiable risk factors Non modifiable risk factors

Smoking

Hypertension

Heavy drinking

OCP

Atherosclerosis

Coffee use

Age

Female sex

Genetics/familial

Collagen vascular diseases

AVMs

What happens if aneurysm is not treated?Risks if not treated: (read next slides)

• Growth of aneurysms• Risk of bleeding

Aneurysm rupture is a devastating event. Approximately 15-20 percent of patients die prior to reaching the hospital and, of those who make it in time, only one-third will have a "good result" after treatment. Therefore, salvage treatment is not effective.

Risk factors for rupture:• Size of the aneurysm• Posterior circulation location• Symptomatic aneurysm• Previous history of bleeding• Increase in size• presence of a daughter sac in the aneurysm, • family history of SAH and

• patients with autosomal dominant polycystic kidney disease (ADPKD)

What is the growth rate of incidentally detected aneurysm?

2 to 4 mm sized incidentally detected aneurysm

Growth is about 2.4% per year.(24 people out of 1000 who have incidentally detected aneurysm will grow in a year)

5 to 9mm Aneurysms 9.1% per year aneurysms will grow

10 to 20mm Aneurysms 50% per year

It is clear from the chart that as the size of the aneurysm increases, the chance of their growth also increases

What is the risk of bleeding of unruptured /incidentally detected aneurysms?

Size of aneurysm Asymptomatic aneurysms With previous symptoms

Less than 10mm 0.05% / year 0.5% / year

10 to 25 mm 1% / Year 1% / year

More than 25 mm 6% / year 6% / Year

Risk of bleeding: ISUIA study:

Size Anterior circulation aneurysms

Posterior circulation aneurysms

Less than 7mm 0.1% 2.5%

8 to 12 mm 2.6% 14.6%

13 to 24 mm 14.5% 18.4%

Morethan 25mm 40% 60%

ISUIA 2 study: risk of bleeding -five years cumulative risk of bleeding

It is clear from the previous slides that both growth of aneurysm and their risk of bleeding

increases as the size of the aneurysm increases.

Therefore large aneurysms and growing aneurysms detected incidentally should be

treated

Treatment options:

1. No treatment(conservative management)

2. Surgical clipping

3. Endovascular coiling

No treatment: conservative management

• Control of hypertension

• Cessation of smoking

• Periodic follow-up imaging( yearly)

• Treatment if the aneurysm is growing or patient complains of headache or if any cranial nerve paresis.

Surgical clipping

Clipping:

Watch following videos for better understanding of clipping

http://www.youtube.com/watch?v=PaTzNaTOoxI

http://www.youtube.com/watch?v=hJACYm7PPg0

Endovascular coiling:Read brain aneurysm coiling presentation to

understand about different techniques of coiling

• Coiling: http://www.youtube.com/watch?NR=1&feature=endscreen&v=5Ss-IOmFyeA

• Flow diverter: http://www.youtube.com/watch?v=jd5VQTS096E&feature=related

• Stent assisted coiling: http://www.youtube.com/watch?v

=MfdPbBZ6ETs&feature=related

Which treatment is better? Coiling or clipping?

Morbidity and mortality:ISUIA study(International Study on Unruptured Intracranial

Aneurysms): this is one of the largest study done on unruptured intracranial aneurysms to date.

The study showed that

Death and dependency at 1 year:

Surgical clipping:• The 30-day overall morbidity and mortality rate with surgery was

13.2%, and the mortality rate was 1.5%. • The 1-year morbidity and mortality rate was 12.2%, and the mortality rate

was 2.3%.

Endovascular treatment:• In the endovascular group, the 1-year total morbidity and mortality rates

were 9.5% and 3.1%, respectively.

Personal comment• It is my personal belief that small aneurysms can also rupture

and it is better to secure them if technically feasible irrespective of what trials and numbers show simply because Aneurysm rupture is a devastating event. Approximately 15-20 percent of patients die prior to reaching the hospital and, of those who make it in time, only one-third will have a "good result" after treatment. Therefore, salvage treatment is not effective.

• One has to take into consideration the psychological factor. No matter what the statistics show, no one can guarantee a risk-free choice. After explaining the pros and cons, we have to take care of the patient’s psychology and help them make decision. If the patient cannot accept the psychological burden of having a 'time bomb' in his /her head, treating a small aneurysm may be justified.

The above clinical trial which is the largest trial to date clearly shows the benefit of both endovascular

coiling and surgical clipping in unruptured aneurysms.

Technically feasible should under go coiling as its minimally invasive, recovary is fast, can be done

under local anaesthesia, and can be discharged on the evening of the procedure.