AVMs of the Posterior Fossa Case Presentation and Literature Discussion Christopher Showers Columbia...
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Transcript of AVMs of the Posterior Fossa Case Presentation and Literature Discussion Christopher Showers Columbia...
AVMs of the Posterior Fossa
Case Presentation and Literature Discussion
Christopher ShowersColumbia University College of
Physicians and Surgeons
Patient CP - HPI
• USH eating dinner sudden onset very severe R H/A with lightheadedness, nausea
• Progressive lethargy LOC en route to CCH• Upon Arrivals: Decorticate Posturing
Intubated; CT head acquired • Emergent R Frontal EVD transfer MGH
Outside H-CT8/14/13 21:13
Patient CP - MGH
• Exam:– Intubated, sedated, no follow commands– L anisocoria (4/3mm) nonreactive b/l, (-)corneals,
(-)OCR, (+)cough, flexion RUE, TF in LLE– GCS: 4-5
• Labs: Na 123; K 5.7• Drips: Mannitol x1; 23% NaCl x2 3% NaCl • EVD: at 0, open no drainage • Repeat CT Head: interval mild progression of
hemorrhage, hydrocephalus
Patient CP
• PMx: L Humoral fracture 1.5wk ago• Meds: ASA 81mg qD; Duloxetine 60mg qD• ROS: L arm pain; no complaints prior • SHx: retired teacher, nonsmoker, active at b/l• FHx: no sudden bleeds
Preop Angio8/15/13 08:30
Right Vertebral Injections
Operative Resection
• SMG 2-3 (1-2S, 1E, 0V)• SOC evacuation of hemorrhage / resection
of AVM; placement of R occipital EVD– Washout of subdural blood– Ligated feeding arteries, identified abnormal
superior vein draining AVM– Another nidus identified anterior superior, not
visualized on angio
Intraop Angio8/15/13 17:02
Right Vertebral Injections
Operative Resection x2
• Rentered initial craniectomy site– Wider area of dissection extensive & diffuse
abnormal vessels draining into large vein extending superiorly
– Skeletonized large vein with generous R cerebellar resection Witnessed to turn blue
• NICU
Post-op H-CT8/15/13 21:38
Post-op Exam
• Pupils symmetric, reactive 32mm b/l• No OCR, vertical bobbing• Mild cough reflex• UE: withdraw to pain b/l• LE: TF b/l
• Deteriorated to extensor posturing UE/LE b/l• Expired on 8/21/13 01:35am
Posterior Fossa AVMs
• 7.5% - 20.0% of all intracranial AVMs (da Costa 2009; Drake 1986; Perret 1966)
– 72.4% Cerebellar / 21.5% Brainstem (da Costa 2009)
• Vermian most common (Sampson 2004)
– Arterial Input distal SCA & distal PICA b/l– Large or involving 4th V deep AICA feeders– Venous Drainage Superiorly to Galenic System
• Greater Rate of Hemorrhage in PF-AVMs– Hemorrhage as presenting symptoms ~90% vs. 29-
54% in ST (Khaw 2004; Stefani 2002; Drake 1986; Solomon 1986)
– Smaller size vs. ST increased hemorrhage risk (Drake 1986; Sampson 1986; Kader 1994; Langer 1998)
– Greater Rate of AA 25% vs. 5-8% in ST (Sampson 1997; Lanzino 1999)
– Bleeds more frequent and FATAL up to 66.7% (Fults and Kelly 1984; Batjer 2009; Symon 1995
– Rebleeding in 6.0% - 17.8%, 34.3% Dw/DD (Mast 1997; Stapf 2006; Steinberg 2008)
• 5-6% annual risk up to 5 years (Halim 2004) vs. 3-4% ST (Baskaya 2006)
Presentation of PF-AVMs
• Rarely present with Seizure– 2/68 (2.9%) attribute to hydrocephalus (Yasargil 1998)
• General Neuro deficits / CN palsy up to 28% (Batjer 2009; Stahl 1980)
– Mass effect– Ischemia – steal phenomenon – Hydrocephalus– CN V palsy
Presentation of PF-AVMs
Treatment • Optimal to defer surgical resection 4 – 6 wks
after initial hemorrhage and clot evacuation– Not possible w/ Life threatening bleed– 53 pf-AVMs 15 emergent operation, AVM
removed at time of evaluation in all (Sampson 2004)
• Preoperative Embolization recommended – Occlude small feeders difficult to locate surgically• Caution occluding large vessels proximally
– Great Benefit in Brainstem AVMs– Mortality 1.3% ; Severe-Mod AE 6.7%, 15.3% (Wikholm
1966)
• Radiosurgery GKRS– Small, unruptured, eloquence, elderly (Ciurea, 2010)
– Latency of obliteration after treatment no abatement of risk in that time (Ciurea 2010)
– GKRS Obliteration: 63% 2y; 73% 3y - 95% stable neurologically (Massager 2000)
• Multimodal Therapy recommended (Steinberg 2008)
– SMG III-IV, mostly brainstem AVM– XRT alone residual AVM on f/u
Treatment
General Outcomes
• Excellent to Good outcomes 71.0% - 82.1%• Poor morbid outcome 13.0% - 22%• Mortality 3.6% - 16.7%(Solomon 1986, Samson 1986; Symon 1995; Drake 1986; Steinberg 2008)
Outcome Associations • 12 pf-AVM w/ hemorrhage (Yilmaz 2011)
– Worse w/ initial mRS, SMG grade, hematoma size• 59 pf-AVM w/ hemorrhage (van Loon 1993)
– Worse w/ degree of 4th V compression, GCS• 98 pf-AVM – 61/98 (62.2%) w/ Hemorrhage (da Costa 2009)
– Worse w/ presence of AA, initial mRS, # of treatments• 48 pf-AVM SMG III-IV (Steinberg 2008)
– 37/48 (77.1%) w/ Hemorrhage; mean f/u 4.8y– Multimodal therapy >> XRT alone
Acknowledgments
• CP&S – Dr. Jeffrey Bruce – Dr. Donald Quest
– SD Andrew Chan– SD Brian Gill
• MGH– Dr. William Butler – Dr. Patrick Codd– Dr. Chris Stapelton– Dr. Peter Fecci
NOTES BELOW HERE
Posterior Fossa AVMs• da Costa 2009– 106 / 678 (15.6%)
• 72.4% Cerebellar / 21.5% Brainstem
• Cooperative Study of Intracranial Aneurysms and SAH (Perret 1966)
– 32/453 7%• Drake 1986– 116/600 20%
• Vermian most common (Sampson 2004)
– Arterial Input distal SCA & distal PICA b/l– Large or involving 4th V deep AICA feeders– Venous Drainage Superiorly to Galenic System
Hemorrhage in PF-AVMs
• Brugge, 2010– 61/98 (62.3%) presented with Intracranial hemorrhage– Hemorrhage reduced mRS at presentation
(p=0.0229) though not final mRS (p=0.41)– AA, poor initial mRS, treatment reduced final mRS– 52 f/u imaging
• 48.9% completelly obliterated • 13.4% smaller but patent nidus• 9.6% uchanged
– 10/61 hemorrhaged in f/u 4.1% risk/year• No difference in treated vs. untreated