Intraobserver and interobserver variability in CT angiography and MR angiography measurements of the size of cerebral aneurysms.
OBJECTIVE
Accurate and reliable measurement of aneurysm size is important for treatment planning. The purpose of this study was to determine intraobserver and interobserver variability of CTA and MRA for measurement of the size of cerebral aneurysms.


METHODS
Thirty patients with 33 unruptured cerebral aneurysms (saccular, >3 mm in their maximal dimension, with no daughter sacs or lobulations) who underwent 256-row multislice CTA, 3-D TOF MRA at 3.0T, and 3D rotational angiography (3DRA) were retrospectively analyzed. Three independent observers measured the neck, height, and width of the aneurysms using the CTA and MRA images. Intraobserver and interobserver variability of CTA and MRA measurements was evaluated using the standardized difference and intraclass correlation coefficient, with 3DRA measurements as the reference standard. In addition, the mean values of the measurements using CTA and MRA were compared with those using 3DRA.


RESULTS
The overall intraobserver and interobserver standardized differences in CTA/MRA were 12.83-15.92%/13.48-17.45% and 14.08-17.00%/12.08-17.67%, respectively. The overall intraobserver and interobserver intraclass correlation coefficients of CTA/MRA were 0.88-0.98/0.84-0.96 and 0.86-0.98/0.85-0.95, respectively. Compared to the height and width measurements, measurements of the neck dimensions showed higher intraobserver and interobserver variability. The sizes of the cerebral aneurysms measured by CTA and MRA were 1.13-9.26 and 5.20-9.67% larger than those measured by 3DRA, respectively; however, these differences were not statistically significant.


CONCLUSIONS
There were no noticeable differences between intraobserver and interobserver variability for both CTA- and MRA-based measurements of the size of cerebral aneurysms.
Department of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, South Korea.
Hye Jeong
HJ
Kim
Department of Radiology, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, 150, Seongan-ro Gangdong-Gu, Seoul, 134-701, South Korea. evee0914@chollian.net.
Dae Young
DY
Yoon
Department of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Gyeonggi-do, South Korea.
Eun Soo
ES
Kim
Department of Radiology, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, 150, Seongan-ro Gangdong-Gu, Seoul, 134-701, South Korea.
Hyung Jin
HJ
Lee
Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea.
Hong Jun
HJ
Jeon
Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea.
Jong Young
JY
Lee
Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea.
Byung-Moon
BM
Cho
D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D000072226:Computed Tomography Angiography; D003287:Contrast Media; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D007479:Iopamidol / Q000031:analogs & derivatives; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012189:Retrospective Studies
D003287:Contrast Media; C057937:iomeprol; D007479:Iopamidol
CT angiography; Cerebral aneurysms; Intraobserver and interobserver variability; MR angiography; Measurement