Table 2:
Distribution of arachnoid granulations documented by imaging and anatomic studies
| Reference | Modality | Patients | Case Type | No. | NOS | Vent. Sup. | Dors. Inf. | TS | SS | TH | StS | VoG | Notes |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Leach et al1 | CT with contrast | 573 | Unselected | 168 | NA | 0 | 1 | 154 | 3 | 8 | 2 | 0 | 3- to 5-mm posterior fossa, 10-mm supratentorial section thickness |
| Leach et al1 | MR with contrast | 100 | Unselected | 14 | NA | 0 | 1 | 13 | 0 | 0 | 0 | 0 | 5- to 6-mm section thickness |
| Leach et al1 | Anatomic | 29 | Unselected | 91 | NA | NA | 0 | 86 | 0 | 5 | NA | NA | Did not assess anterior superior SSS, included posterior inferior |
| Roche et al3 | MR, CT, angiography | 32 | Selected | 42 | NA | 0 | 0 | 36 | 4 | 2 | 0 | 0 | Selected cases |
| Liang et al4 | MR with contrast | 100 | Unselected | 433 | NA | 227 | 6 | 122 | 0 | 0 | 76 | 2 | Assessed all dural sinuses, 3D MPRAGE, 1.3-mm section thickness |
| Gailloud et al13 | Angiography | 57 | Unselected | 15 | NA | 0 | 2 | 12 | 0 | 1 | 0 | 0 | All 12 TS AGs at vein of Labbe entrance site, angiographic study |
| Browder et al6 | Anatomic | 295 | Unselected | 25 | NA | 0 | 2 | 23 | 0 | 0 | 0 | 0 | Only counted large protuberances |
| Ikushima et al19 | MR | 1118 | Unselected | 134 | 5 | NA | NA | 115 | 3 | 8 | 3 | 0 | Noncontrast MR |
| Koshikawa et al20 | MR | 151 | Unselected | 162 | NA | NA | NA | 162 | NA | NA | NA | NA | TS only |
Note:—TS indicates transverse sinus; SS, sigmoid sinus; TH, torcular herophili; StS, straight sinus; VoG, vein of Galen confluence with StS; Vent. Sup., ventral superior SSS; Dors. Inf., dorsal inferior SSS; NA, not applicable; AG, arachnoid granulation; MPRAGE, magnetization-prepared rapid acquisition of gradient echo; SSS, superior sagittal sinus; NOS, location not otherwise specified.