Table 1 Demographics and characteristics of the 42 patients with occipital AVMs

M/F (ratio)

29:13

Mean age in yrs (range)

26.0 (6–47)

Side (L/R)

21:21

AVM size

 <3 cm

11

 ≥3 cm, <6 cm

28

 ≥6 cm

3

Venous drainage

 Superficial

28

 Deep

14

Diffuseness

 Compact

24

 Diffuse

18

Spetzler-Martin grade

 I

2

 II

19

 III

14

 IV

7

 V

0

AVM-OR

 <5 mm

34

 ≥5 mm

8

AVM-VC

 <5 mm

17

 ≥5 mm

25

History

 Hemorrhage

15

 Headache

16

 Seizure

9

 Dizziness

2

VF

 Grade 0

28

 Grade 1

8

 Grade 2

2

 Grade 3

4

 Grade 4

0