Abstract: INTRODUCTION: There is an ongoing controversy on the predictive value of the disperse variables involved in cerebral aneurysm rupture. A better understanding of how such variables interact with each other is needed. OBJECTIVES: The initial aim of the study was to propose how exactly, into a hemodynamic model, such morphologic variables might work together to optimize such predictive rupture value. METHODS: We hypothesized, based on previous research, that the aneurysm rupture phenomenon might be related to hemodynamic interference. Hence, we selected the Helmholtz’s resonator equation because its resemblance to aneurysm morphology and that it may also be used on elastic walls. We collected the morphologic data (transverse area of the neck diameter, the length of the neck, the aneurysm height, length, and width radius) from the unique large enough published series ( n = 425) for ruptured ( n = 140) and no ruptured ( n = 285) aneurysms that included all the required variables by the equation on the same sample. Given that the Helmholtz’s equation also requires as an input variable the speed of the pulse wave (PW), we collected these data from the published series that provides this information by age. This proposed arrangement provided the cerebral aneurysm resonance frequency (the hemodynamic vibratory frequency range, in Hertz, where aneurysms might adsorb most of the oscillating PW energy) for ruptured and no ruptured aneurysms (RAs) by age. Hence, at this point, the working hypothesis was to figure out the predictive value for rupture when the aneurysm resonant frequency (maximal vibratory energy absorption) in Hertz equals the PW frequency range of maximal vibratory energy transmission of 225–275 Hz. RESULTS: What we found is that the mean of the resonance frequency values of the RA series almost entirely matches into the PW frequency range of 225–275 Hz (α < 0.016, β = 0.4, and power = 0.6). Interestingly, the mean of the resonance frequency values for the no RA series barely intersects such PW frequency range (α < 0.024, β = 0.4, and power 0.6). In synthesis, we propose a novel multivariate hemodynamic vibratory interference phenomenon for aneurysm rupture that is activated when the PW frequency matches the resonant frequency of a cerebral aneurysm. The results turned out to have a 99.04% of negative predictive value. DISCUSSION: We hope that a better understanding of this phenomenon might preclude superior treatment strategies. This manuscript aims to provide additional predictive value to better detect patients on a crash course with aneurysm rupture. The required input parameters may be swiftly acquired during an individualized assessment. With this model, PW frequency and hemodynamic interference seem to emerge as novel arterial-damaging factors. CONCLUSION: The Specifity of 97.54%, reflects the ability of the model to correctly identify individuals with lower risk of cerebral aneurysm rupture.
Acevedo et al. (Mon,) studied this question.