This document provides information on treatment options and surgical approaches for cavernous malformations. It discusses observation and radiation therapy as non-surgical treatment options and outlines surgical indications. The key surgical techniques described include the midline suboccipital, orbitozygomatic, retrosigmoid, far lateral, supracerebellar infratentorial, and interhemispheric transcallosal approaches. Post-operative management involves monitoring for neurological deficits and recurrence with imaging. The goal of surgery is complete resection while minimizing damage to eloquent areas.

1. Supratentorial and
infratentorial cavernous
malformation
Youmans Chapter 394
Gregory P. Lekovic
Randall W. porter
Robert F.Spetzler

2. Outline
• Treatment
• Opearative procedure
• Surgical approaches

3. Treatment
• Observation
• Radiation therapy
• Surgical indication
• Contraindication

4. Observation
• For pt whose symptoms resolve completely after an
acute hemorrhagic event
• For pt with incidentally discover lesion(extremely low for
bleeding and chance for seizure 2-3 % per year)
• observation and repeat imaging
• Not restrict activity
• Anticoagulant not contraindication
• Reassure

5. Radiation therapy
• Radiation therapy or stereotactic irradiation has not
been to confer a protective benefit from hemorrhage in
CM
• Neurological deficit in eloquent area
• Not recommend in deep-seated CM

6. Surgical indication
• CM located anywhere in the ventricular system
• CM of the thalamus or basal ganglia or deep seated
lesion
– Acute hemorrhage : mass effect
– Intralesional hemorrhage :mass effect
• Posterior fossa lesion outside brainstem
– Acute hemorrhage : mass effect
– Rupture multiple time
– Expansion lesion
– Intralesional hemorrhage :mass effect
• Refractory epilepsy

7. Contraindication
• Severe medical problem
• Single hemorrhage episode from brainstem CM in an
unfavorable location(far from pia surface)
• Multiple CMs,unless an individual focus can be identified
• Unexpect bleeding in posterior fossa lesion
– Bleeding
– Significant change in neuromonitoring

8. Operative procedure
• Goal of surgery and patient counseling
• Preoperative imaging
• Intraoperative monitoring
• Surgical technique
• Role of intraoperative MRI
• Postoperative management

9. Goal of surgery
and patient counseling
• Posterior fossa or deep-seated lesion
– Extirpate with minimizing the amount of normal eloquent
– Preserve venous anomaly
• Superficial supratentorial CM
– Resect completely with minimal morbidity and excellent outcome
• No attempt to resect hemosiderin-laden brain
• Patient educated : their deficit are likely to worsen after
surgery but will typically improve with time

10. Goal of surgery
and patient counseling
• Best surgical method : two point method
– One point center
– Second is placed where the lesion near pia surface

11. Preoperative imaging
• MRI imaging : pathognomonic
• Angiography is not indicated

12. Intraoperative monitoring
• SSEP, electroencephalography
• Brainstem : motor evoke potential and brainstem
auditory evoked potential(BEAR)

13. Surgical technique
• Opening by using hemosiderin staining or a bulge in the
brainstem as guide
• Framless stereotactic guide
• Exophytic lesion : mulberry
• Mindful of the ubiquitous venous anomaly
– Large : venous infarction
– Small : coagulate and transect

14. Role of intraoperative MRI
• For complete resection
• Or Frameless stereotaxy

15. Postoperative management
• Superficial supratentorial lesion : similar to patient for
undergoing for tumour in same location
• Brainstem
– good cough and gag reflex  extubate
– Evaluate post operative swallowing
– Minimal : short-term tracheostomy or feeding tube
• Patient stable : MRI POD 1
• Follow up imagine annually for the first few years to
monitor for progression or recurrence

16. Surgical approaches
• Midline suboccipital approaches
• Orbitozygomatic approach
• Retrosigmoid approach
• Far lateral approach
• Supracerebellar Infratentorial approach
• Interhemispheric Transcallosal approach

17. Midline suboccipital approach

18. Midline suboccipital approach
• For
– Cerebellar
– posterior cervicomedullary junction
– midline of floor of the 4th
ventricle
• Position : prone, neck flex
• Incision : midline incision from C3 to inion
• Fascia : Y-shape cuff
• Dura : Y-shape
• Suboccipital craniotomy

19. Orbitozygomatic approach

20. Orbitozygomatic approach
• For
– Anterior and lateral midbrain
– Interpeduncular region
– Rostal pons
– Pontomesencephalic junction
– Optic chiasm
– Hypothalamus
• Position : supine with head rotate 30-60 degree,slight
extension neck
• Incision : root of zygoma anterior to tragus 1 cm to the
midline or contralateral midline

21. Orbitozygomatic approach
• Pterional craniotomy
• Orbitozygomatic osteotomy
– Root of zygoma
– Temporal process of zygomatic bone
– Inferior orbital fissure to second cut
– Orbital surface of frontal bone to superior orbital fissure
– Inferior orbital fissure across greater wing to posterior orbit
– Fifth cut to superior orbital fissure
• Dura : medial superior orbital margin to temporal tip

22. Retrosigmoid approach

23. Retrosigmoid approach
• For
– Posterolateral pons
– Lateral middle cerebellar peduncle
– Superior lateral medulla
– Cerebellopontine angle
• Position : lateral decubitus position
• Incision : above auricle and curves behind the ear
• Craniotomy : beware transverse sinus : line from the
root of zygoma to inion
• Dura : curvilinear base on transverse sigmoid junction

24. Far lateral approach

25. Far lateral approach
(transcondylar approach)
• For
– Vertebrobasilar junction
– Inferolateral pons
– Anterolateral medulla
– Upper cervical spinal cord
• Position : Modified park bench position
• Incision : hockey-stick (midline at C2, superior and curve
anterior and lateral to mastoid tip)
• Clivus perpendicular to the floor
– Flexion in AP until the chin is one FB from the clavicle
– Rotation 45 contralateral to lesion side
– Lateral flexion 30 to the floor
– Slight distraction

26. Far lateral approach
(transcondylar approach)

27. Far lateral approach
(transcondylar approach)
• Posterior arch of C1 was removed
• Lateral suboccipital craniotomy
• Can access
– C1 and C2 rootlet
– cerebellum; lower pons
– cranial nerves IX, X, XI, and XII
– vertebral arteries
– ipsilateral posterior inferior cerebellar artery

28. Supracerebellar infratentorial approach

29. Supracerebellar infratentorial approach
• For
– midline tectum and pineal region
• Position : Prone, neck flex
• Craniotomy
– extend above and below the transverse sinus to expose the
junction of the tranverse sinus and torcular
– Single burr hole lateral to SSS
• Dura : v shaped

30. Interhemispheric transcallosal
approach
• For
– Deep-seated supratentorial lesions : thalamus, lateral ventricle,
third ventricle, and corpus callosum
• Approaching the lesion from the contralateral side
• Position : supine
• Incision : linear incision oriented in the coronal plane
• Craniotomy extend contralateral 1 cm