Risk of Aneurysmal Rupture: The Importance of Neck Orifice PositioningAssessment using Computational Flow Simulation

Miyachi, Shigeru

doi: 10.1227/01.NEU.0000342794.00063.16

Nagoya, Japan

Article Outline

In Reply:

Dr. Quigley's remarks are accurate. In our study (1), the aim of the clinical research was not to conduct a confirmatory study, but, rather, an exploratory one, with regard to the possibility of assessment from simple clinical findings.

The percentages of ruptured cases were Type-B, 69%; Type-C, 40%; and Type-A, 28%; consequently, the 3×2 χ2 yields a P value of 0.0365, as mentioned by Dr. Quigley. We avoided drawing a definitive conclusion about comparisons in each group because of the small numbers in our study; for example, there were only 5 cases in Type-C.

As a result of the χ2 comparisons, Type-A versus Type-B, Type-A versus Type-C, and Type-B versus Type-C had P values of 0.025, 1.000, and 0.530, respectively. There was no statistical significance with a Bonferroni correction, but the results suggested the possibility of different risks of rupture, between Type-A and Type-B in particular. As a next step, we are considering confirmatory research to obtain clinically “significant” data.

Shigeru Miyachi

Nagoya, Japan

1. Ohshima T, Miyachi S, Hattori K, Takahashi I, Ishii K, Izumi T, Yoshida J: Risk of aneurysmal rupture: The importance of neck orifice positioning—Assessment using computational flow simulation. Neurosurgery 62:767–775, 2008.
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