- 1Environmental and Occupational (Integrative) Physiology, Haute Ecole Paul Henri Spaak, Brussels, Belgium
- 2Research Division, Divers Alert Network Europe, Brussels, Belgium
- 3Faculté des Sciences de la Motricité, Université Libre de Bruxelles, Brussels, Belgium
- 4Center for Hyperbaric Oxygen Therapy, Military Hospital Queen Astrid, Brussels, Belgium
by Gempp. E. (2016). Front. Psychol. 7:1254. doi: 10.3389/fpsyg.2016.01254
We are grateful to Dr. Gempp to let us clarify and explain our choices.
We would like to confirm that the quoted reference was the one that we have chosen. We indeed are aware of the other reference (Gempp et al., 2010), but we deliberately didn't choose this paper for reasons that are expressed by Dr Gempp himself: ≪.…we clearly showed […] in 34 military divers who strictly adhere to decompression procedures……≫. Since the decompression procedures that the French Navy are using are quite different of those used by the divers in our study (the speed of ascent, for instance, is roughly 33% faster in the French Navy procedures) and Navy divers strictly adhere to these procedures, as opposed to the more liberal approach (in both directions of conservatism) of recreational divers, this makes the two diver populations possibly very different. We are in fact aiming our work on recreational divers.
Considering the other references referring to white matter hyperintense spots, these MRI findings are actually still considered asymptomatic and their clinical significance is unknown; furthermore, although proposed in the literature, the morphology of these hyperintensities does not seem to indicate a definite vascular origin (Balestra et al., 2004).
In our Discussion, we have taken the time to explain some of the limitations of the studies that can be found in the literature. We furthermore encourage the reader to consider a Letter to the Editor which we wrote in reaction to one of the most cited articles on the topic (Torti et al., 2004), highlighting, among other methodological issues, the high risk of self-selection bias in such studies (Germonpre and Balestra, 2004).
As Dr Gempp adequately pointed out, the number of asymptomatic hyperintense white matter spots is lower in our study. This merely illustrates the importance of mitigating, when designing such studies, common biases like self-selection, specific (non-recreational) decompression procedures, non-recreational diver populations, non-randomization as well as non-homogenous samples. All these factors may result in a higher prevalence of asymptomatic white matter spots found by MRI imaging than are actually present in the actual intended study population.
We would like to thank Dr Gempp for his encouragement to move toward a prospective study in order to analyze adequately the relative risk of Patency of Foramen Ovale and decompression sickness in recreational SCUBA divers. We can assure him that such studies are well underway and will be published shortly.
Author Contributions
We answered to the commentary on our article after mutual acceptance of the manuscript proposed.
Conflict of Interest Statement
The handling Editor declared a shared affiliation, though no other collaboration, with one of the authors CB and states that the process nevertheless met the standards of a fair and objective review.
The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
References
Balestra, C., Marroni, A., Farkas, B., Peetrons, P., Vanderschueren, F., Duboc, E., et al. (2004). The Fractal Approach as a tool to understand asymptomatic Brain Hyperintense MRI Signals. Fractals 12, 67–72. doi: 10.1142/S0218348X0400232X
Germonpre, P., and Balestra, C. (2004). Risk of decompression illness among 230 divers in relation to the presence and size of patent foramen ovale. Eur. Heart J. 25, 2173–2174. doi: 10.1016/j.ehj.2004.07.042
Gempp, E., Sbardella, F., Stephant, E., Constantin, P., De Maistre, S., Louge, P., et al. (2010). Brain MRI signal abnormalities and right-to-left shunting in asymptomatic military divers. Aviat Space Environ. Med. 81, 1008–1012. doi: 10.3357/ASEM.2786.2010
Keywords: diving, long-term effects, persistent foramen ovale, brain MRI, cerebral embolism
Citation: Balestra C and Germonpré P (2016) Response: Commentary: Correlation between Patent Foramen Ovale, Cerebral “Lesions” and Neuropsychometric Testing in Experienced Sports Divers: Does Diving Damage the Brain? Front. Psychol. 7:1586. doi: 10.3389/fpsyg.2016.01586
Received: 18 August 2016; Accepted: 29 September 2016;
Published: 24 October 2016.
Edited by:
Ana-Maria Cebolla, Université Libre de Bruxelles, BelgiumReviewed by:
François Guerrero, University of Western Brittany, FranceJacek Kot, Gdańsk Medical University, Poland
Copyright © 2016 Balestra and Germonpré. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Costantino Balestra, Y29zdGFudGlub2JhbGVzdHJhQGdtYWlsLmNvbQ==