Indications for Procedure
The operative goal is selective occlusion of the aneurysm to prevent rebleeding, while preserving all normal vessels and avoiding additional injury to the brain. Given the long life expectancy of children, the treatment should have low morbidity and mortality risks and should provide durable long-term cure. Indications for embarking on treatment are as follows:
- Ruptured intracranial aneurysms
- Symptomatic unruptured intracranial aneurysms
- Incidental intracranial aneurysms: Treatment indications are subject to controversy, even in adults. Important aspects in favor of treatment are previous rupture of a different aneurysm, positive family history, aneurysm size > 7 mm, aneurysm lobulation, aneurysm growth or de novo occurrence on serial imaging, life expectancy, and individual risk of treatment (17). These aspects can be used when counseling parents in the rare event of an incidental pediatric aneurysm.
- Vital signs: Blood pressure (aim is normotension for age).
- CSF drainage parameters: When an EVD has been inserted prior to surgery the aim should be physiological ICP for age. We never drain more than 3–5ml CSF at a time to avoid provocation of rebleeding.
- Medication: While oral or intravenous nimodipine is standard treatment in adults with ruptured aneurysms, this drug should be very carefully administered in children. There are no controlled trials in children, and data from small series suggest a substantial risk of induced arterial hypotension (26).
- Antibiotics: Intravenous antibiotics are given at induction.
- Anticipation of blood loss: Adequate vascular access and availability of crossmatched blood products is of paramount importance. The use of a cell saver system should be discussed.
- Blood pressure control: Normotensive blood pressure should be aimed for, although temporary hypotension during clipping might be required in selected cases.
- Cardiac standstill ± hypothermia during clipping: This maneuver is considered helpful in rare circumstances (30).
Devices to Be Implanted
- Vascular clips: An array of aneurysm clips should be readily available.
- Intraoperative angiography: Microscope-based indocyanine green (ICG) video angiography provides real-time information about patency of vessels and aneurysm occlusion, resulting in clip replacement in 10% (55).
- Micro-Doppler sonography: This modality can be used to assess patency of vessels.
- Intraoperative neuromonitoring: This might be useful to detect ischemia at a very early stage and thus indicate the need for clip reevaluation and repositioning (62).