9.1.1 Symptoms and Signs

• Headaches progressively increasing in frequency and severity

• Nausea and/or vomiting
• Lack of appetite
• Neck pain/stiffness
• Blurred vision, double vision, or loss of peripheral vision
• Seizures
• Loss of memory or confusion
• Reduction in hearing capabilities
• Fever
• Difficulty maintaining balance and properly performing movements
• Unilateral paralysis
• Weakness/Numbness in arm/leg
• Difficulty speaking
• Cognitive deficiency

9.1.2 Surgical Pathology

• Cranial benign/malignant vascular lesion

9.1.3 Diagnostic Modalities

• Physical examination
• Neurological examination
• Cerebral angiography(see ▶Fig. 9.1)
  

  

• MRI of brain (if positive, angiogram performed)
• CT scan of brain (if positive, angiogram performed)

9.1.4 Differential Diagnosis

• Arteriovenous malformation (AVM)
• Cavernoma (cavernous angioma) (see ▶Fig. 9.2)
  

  

• Mixed malformation
• Dural arteriovenous fistula (DAVF)
• Telangiectasis
  • Capillary telangiectasia (CTS)

• Venous malformation

  • Developmental venous anomaly (DVA)
• Vein of Galen malformation
• Cerebral aneurysm (see ▶Fig. 9.3)
  

  

• Moyamoya disease

9.1.5 Treatment Options

• Conservative observation
• Radiation therapy
  • Conventional radiation therapy
  • Three-dimensional conformal radiation therapy (3D-CRT)
  • Intensity modulated radiation therapy (IMRT)
  • Proton therapy
  • Radiosurgery/CyberKnife treatment
• Surgery
  • Microsurgical resection
  • Preferred option if bleeding or seizures result from lesion

• Endovascular embolization using the following embolic agents (initial procedure to facilitate surgery):

  • Coils: Close down vessel supplying AVM (cannot independently treat AVM nidus)
  • Onyx: Solidifies, forming a cast, in vessel supplying AVM (best penetration of AVM nidus)
  • NBCA: Solidifies as a glue in vessel supplying AVM (greater risks and worse outcomes than with Onyx)
  • PVA: Used prior to craniotomy or surgical resection of AVM (cannot independently treat AVM pathology)
• Combination techniques
  • Embolization followed by stereotactic radiosurgery
• Venous angiomas should not be treated unless certainly contributing to intractable seizures and bleeding

9.1.6 Indications for Surgical Intervention

• No improvement after nonoperative therapy (physical therapy, pain management, radiation treatment, and chemotherapy)
• Palliative treatment when symptomatic vascular lesion not entirely treatable by other approaches
• Vascular lesion surgically accessible, sufficiently small, and near surface of brain
• Presence of associated lesions (aneurysms/pseudoaneurysms on feeding pedicle or nidus, venous thrombosis, venous outflow restriction, venous pouches, dilatations)

9.1.7 Surgical Procedure for Microsurgical Resection (Vascular Lesions)

1. Informed consent signed, preoperative labs normal, patient ceases intake of NSAIDs (Naprosyn, Advil, Nuprin, Motrin, Aleve) and blood thinners (Coumadin, Plavix, Aspirin) 1 week prior to treatment
2. Appropriate intubation and sedation and lines (if necessary) as per the anesthetist
3. Place patient in supine position with Mayfield pins, all pressure points padded, and head turned to relevant side of vascular lesion
4. Cleanse patient’s skin overlaying surgical site with antiseptic solution
5. Neuromonitoring may be present to monitor nerves
6. Time out is performed with agreement from everyone in the room for correct patient and correct surgery with consent signed

7. Perform arched incision on scalp along AVM/vascular lesion (cavernoma, etc.), folding soft tissue back

8. Drill small holes in the skull and create a skull flap (craniotomy)
9. Open the dura, allowing direct access to vascular lesion
10. IF AVM, separate AVM and clamp the blood vessels on both sides of the malformation, cutting off blood circulation to the abnormal vessels, starting with supplying arteries then nidus and finally the draining veins
11. If cavernoma, remove the cavernoma en bloc by separating mass from surrounding parenchyma of brain
12. If aneurysm, carefully isolate the aneurysm neck with proximal and distal arterial control prior to placing appropriate clips across neck (given preoperative preparation demonstrates this aneurysm to be favorable for clipping with large neck rather than endovascular treatment needing smaller neck of aneurysm)
13. Carefully free and surgically remove AVM/vascular lesion
14. A drain may be placed at the surgical site, preventing fluid build-up
15. Ensure that the AVM/vascular lesion is entirely resected
16. Close dura in watertight fashion
17. Return or replace skull flap, using screws and plates if necessary
18. Seal back the skin flap with surgical staples or sutures