Radiosurgery for intractable seizure with cavernous malformations

Transcription

1 Radiosurgery for intractable seizure with cavernous malformations Y. Kida, T. Hasegawa, T. Kato Ookuma Hospital and Komaki City Hospital Scientific Committee of JGKS

2 WE SWEAR THAT WE HAVE NO CONFLICT OF INTEREST.

3 Risk of developing seizure after diagnosis of CM Reporter Journal New seizure appeard Patient-year Konziolka et al 1995 Del Curling et al 1991 Moriarity et al 1999 J Neurosurg 4.3 % J Neurosurg 1.5 % Neurosurg Clin N Am 2.4 %

4 Combined treatment withmeg + GK MEG: Searching for seizure focus GK: Treatment of intractable seizure

5 Hemosiderin deposits and seizure focus found by MEG We consider that CMs with seizure have two pathological status (1)Hemorrhage in CM (2) Epilepsy in surrounding brain

6 Seizure dipoles are clustered only around frontal lobe lesion!! MEG:Before GKS Two CMs with frequent Seizures ( 13 y.o., Male)

7 Rationale 1 Symptomatic CM cause intractable seizure often 2 Seizure control is usually very difficult even after various medication 3 Seizure focus are found widely around CM lesion 4 Surgical resection of seizure focus is not a easy task 5 Even after resection, seizures may persist

8 Inclusion Criteria 1 Intractable seizure at least with weekly basis 2 Difficult to control by medication (More than 2 anticonvulsants) 3 Difficult to resect the lesion (eloquent or deep) 4 Refractory seizure after surgery 5 Hesitate or dislike the surgery

9 Radiosurgery of CMs with intractable seizures(44 cases) Cases Range Mean 1) Age years 2) Lesion Size mm 3) Max. Dose Gy 4) Marg. Dose Gy

10 Seizure Frequency Interval between the onset to GK (months) Weekly Monthly Daily Most of the cases are within 4 years

11 Location of the lesions Seizure Pattern Most of the lesions are located in frontal or temporal lobe. Seizure patterns are equqlly separated. 14

12 Seizure and lesion control 1 8 Edema(3) Seizure(1) Hemorrhage(2) New lesion(2) 13 (30.2%) (32.5%) 24 (55.8%) 14 (32.5%) 1 Seizure (Engel) Lesion control

13 Cavernous Malformation in Lt F (44y.o., Female) RS (36/18 Gy) No MRI changes (24M) After radiosurgery, seizures decreased gradually and completely disappeared within 2 years.

14 Cavernous Malformation with Intractable Seizure (19 y.o., F) GK(28/25.2 Gy) 60 Months 153 Months Because of severe perifocal edema, she was

15 Cavernous malfomation with frequent Seizures and surgically treated first T2WI T2 * WI T2 Star images show hemosiderin deposits Case 2

16 MEG ( 23 y.o., Male) MEG shows seizure dipoles just around CM, chiefly in anterolateral portion.

17 After surgery (lower), hemosiderin deposits were less apparent, but still remain. T2 * WI Preop Postop

18 MEG (2 years after surgery) showed a seizure dipole cluster again.

19 GK : 40/20 Gy (2012.6) Seizures decreased up to Engel Class II

20 Pathogenesis of CM If this particular case is treated with GK, hemorrhagic lesion which create neurological signs hopefully treat l at most 15 Gy at the margin Hemosiderin deposition in surrounding brain tissue, causing epilepsy Hopefully require more than 20 Gy at the margin Very diffgicult

21 Cumulative occurrence of edema (+) 11 (-) 33

22 Edema-free Survival < 17Gy A<17Gy B 17Gy 17 Gy or more 17 Gy or more Statistically not significant

23 Various questions against radiosurgery for intractable seizure 1) Can radiosurgery control seizure 2) If so, how much dose or volume required Yes, but not for all At least 20 Gy or more 3) What is the mechanism Radiation injury? Neuromodulation? 4) How to find out the focus EEG, MEG, ECoG 5) How long does it take At least several months? Seizure control is less consistent than surgery, and requiring longer time for the control.

24 Seizure Control after Surgery Author Year No of Case F-U Surgery Seizure Control Adverse Effects Excision of Hemosideri n rim Baumann 2007 Stavrou (25ms) 53 (8.1 years) Complete 1 year 70% 2 year 68% 3 Year 65% A:Lesionecto my B:w/surroun ding gliosis 7.0% NA Class I:84.9% 7.5%: 18/53 cases Slightly better outcome Englot Gross total:77% Subtotal::8% Seizure free:75% NA Lesionecto my only:76% w/corticect omy:75% Seizure control seems to be better than radiosurgery, but the recurrence is not rare.

25 Conclusion 1) Seizure control is not good enough after radiosurgery possibly due to uncirtain localization of focus, large target volume and for adverse effects. Strict dose gradient may be required for controlling two pathological processes. 2) It takes a long time for the control, required a surgery sometimes. 3) Thus the Indication for radiosurgery is limited so far. 4) To date, adequate to add radiosurgery only for recurrent seizure after surgery

26 51 y.o., Male Treated 30/15 Gy Cavernous malformation associated frequent partial seizure, treated with gamma knife.

27 GK Epilepsy attacks per month Carbamazepine > TPM-> Search for adequate medication of anticonvulsant is required