[Parenchymal changes after radiosurgery of cerebral arteriovenous malformations. Clinical and MRI data].
OBJECTIVE
Purposes of this study are to describe different parenchymal changes seen after radiosurgery of cerebral arteriovenous malformations and the clinical symptoms which can be associated, and risk factors correlated with them.


METHODS
and method. From the whole population of 705 patients with a cerebral arteriovenous malformations treated by radiosurgery between 1984 and 1998, clinical from 615 patients and post radiosurgery MRI data from 367 patients were reviewed. Neurological deficit occurred in 5.37% of cases and was still persistant in 1.46% of cases. Delay of occurrence of deficits ranged from 6 to 83 months (mean: 27 months, median: 15 months). Parenchymal changes seen in MRI were classified in 4 grades: 1 without parenchymal changes, 2 hypersignal in sp T2, 3=2 with homogenous enhancement with gadolinium, 4 with hyposignal in spT1 and annular irregular enhancement. Several parameters (size, volume, angioarchitecture of the cerebral arteriovenous malformation, dosimetric parameters) were studied and correlations were searched by uni and multivariate analysis with occurrence and delay of occurrence of deficits or parenchymal changes.


RESULTS
In multivariate analysis, only size was significantly correlated with occurrence of parenchymal changes (p=0.0016); only size of the malformation was significantly correlated with delay of occurrence of parenchymal changes (p=0.0082); only grade 4 was correlated with occurrence of neurological deficit (p<0.00001). However, when only "a priori" parameters (known before radiosurgery) are introducted in logistic model, size taille (p=0.02) and hypoplasy of a sinus (p=0.0049) are significantly correlated with occurrence of neurological deficit. Only parenchymal changes grade 4 was significantly correlated with delay of occurrence of a neurological deficit (p<0.00001). However, when only a priori parameters (known before radiosurgery) are introducted in logistic model, only arterial steal (p=0.054) was significantly correlated with delay of occurrence of a neurological deficit.


CONCLUSIONS
Parenchymal changes are various in expression, signification and clinical symptoms associated with them. They must be known and recognized for better prevention and symptomatic treatment as well.
Nataf
F
F
Service de Neurochirurgie, Centre Hospitalier Sainte-Anne, 1, rue Cabanis, 75674 Paris Cedex 14, France.
Ghossoub
M
M
Missir
O
O
Beuvon
F
F
Varlet
P
P
Merienne
L
L
Schlienger
M
M
Roux
F X
FX
D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology / Q000528:radiation effects*; D001925:Brain Damage, Chronic / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D001929:Brain Edema / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D002543:Cerebral Hemorrhage / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D002648:Child; D003131:Combined Modality Therapy; D003287:Contrast Media; D018572:Disease-Free Survival; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D002538:Intracranial Arteriovenous Malformations / Q000453:epidemiology / Q000473:pathology / Q000601:surgery* / Q000628:therapy; D020767:Intracranial Thrombosis / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D015999:Multivariate Analysis; D009336:Necrosis; D009457:Neuroglia / Q000276:immunology / Q000473:pathology / Q000528:radiation effects; D009474:Neurons / Q000473:pathology / Q000528:radiation effects; D010291:Paresis / Q000453:epidemiology / Q000209:etiology; D010297:Paris / Q000453:epidemiology; D011184:Postoperative Period; D011832:Radiation Injuries / Q000453:epidemiology / Q000209:etiology* / Q000473:pathology; D016634:Radiosurgery / Q000009:adverse effects* / Q000379:methods; D012189:Retrospective Studies; D014657:Vasculitis / Q000453:epidemiology / Q000209:etiology / Q000473:pathology
D003287:Contrast Media