Indications
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Spontaneous intracerebral hemorrhage (ICH)
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Deep-seated and lobar hematomas with suspected underlying hypertension or cerebral amyloid angiopathy
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Moderate-sized and large hematomas (>20 mL)
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Normal coagulation parameters (international normalized ratio [INR] < 1.3, prothrombin time < 14, and partial thromboplastin time < 30 to 32 seconds or local normal range), platelet counts greater than 100,000/μL, and no evidence of platelet dysfunction other than aspirin effect (i.e., known use of clopidogrel [Plavix])
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Stable clot volume (as evidenced by radiographic imaging 6 hours later)
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Stable or slowly declining neurologic condition
Contraindications
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The procedure is contraindicated in patients with poor functional status or multiple medical comorbidities that put them at a high surgical risk or preclude meaningful recovery or rehabilitation.
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Glasgow Coma Scale score 4 or less or extension of ICH into the brainstem typically precludes meaningful recovery.
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Infratentorial hemorrhage (including cerebellum) requiring surgery is better approached with open suboccipital craniotomy.
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Patients with rapidly deteriorating neurologic condition or signs of impending herniation, or both, are better treated with open surgical evacuation of ICH and other decompressive techniques.
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Secondary hematomas resulting from vascular malformation, tumor, or ruptured aneurysm are inappropriate for image-guided surgery and are better suited for an open procedure that can address the primary process causing the bleed.
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Small (<20 mL) or asymptomatic lesions should be managed expectantly because risk of intervention may not be justified.
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Progressively enlarging ICH should not be treated with catheter evacuation and may require open surgery to address an active bleeding source.
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Coagulopathy and abnormal platelet counts or function should be corrected, and clot stability should be established. Elevated INR and prothrombin time are often found in patients on warfarin and can be reversed with vitamin K, fresh frozen plasma, and recombinant factor VIIa (NovoSeven). Heparin-induced coagulopathy can be reversed with protamine sulfate. Patients with platelet counts less than 100,000/μL and known platelet dysfunction (other than aspirin effect) should be treated with platelet transfusions.
Planning and positioning
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Initial imaging of a patient with ICH-like symptoms is typically with a computed tomography (CT) scan because it quickly establishes diagnosis and assesses ICH volume. To ensure that the hematoma is not expanding, follow-up CT scan should be performed about 6 hours later. If the volume of the hematoma is significantly enlarged (>5 mL growth), catheter placement should be postponed until the clot has stopped expanding, or open surgical evacuation should be considered if the patient is rapidly deteriorating. Correction of coagulopathy is essential to allow stabilization of ICH before catheter placement.
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A search for the etiology should be performed, particularly in younger patients and patients without a history of uncontrolled hypertension, to exclude an underlying vascular malformation, tumor, or aneurysm. This evaluation can best be accomplished using contrast-enhanced CT and CT angiography (CTA). Magnetic resonance imaging (MRI) without and with gadolinium contrast agent is preferred if tumor or hemorrhagic conversion of ischemic stroke is suspected. Often the image guidance planning test (CTA or MRI) can also serve as the stabilization scan, so one should plan accordingly with placement of scalp fiducial markers if needed for the image guidance system. A catheter cerebral angiogram is required if CTA is negative but aneurysm is still strongly suspected (significant associated subarachnoid hemorrhage or ICH distribution adjacent to sylvian or interhemispheric cisterns).
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Entry point should be selected from the imaging studies so as to allow the least intrusive access to the ICH and a catheter trajectory along the long axis of the clot. For most deep ganglionic bleeds, a frontal or parietooccipital burr hole is most appropriate. For lobar hemorrhages, a burr hole is selected overlying the closest extension of the ICH to the cortical surface.
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Correction of coagulopathy should be verified (verify normal INR and partial thromboplastin time) before starting the procedure, and platelet transfusion may be initiated before and completed during the procedure.
Figure 35-1:
After induction of anesthesia, the patient’s head is fixed in a three-point Mayfield head rest, and the frameless navigation base station is secured to the head clamp. Skull fixation is unnecessary if electromagnetic guidance is used. Fiducial markers (or surface anatomic landmarks) are registered with the treatment planning platform.
Figure 35-2:
Navigation is established and verified, aiming for 1- to 2-mm precision at the catheter trajectory. The surgical plan is selected, with desired catheter entry and target points and trajectory depth allowing catheter perforations within the depth of the clot.
