Selected scientific publications on diving medicine and physiology.

2005 Mar 6
Pulpal and periodontal temperature rise during KTP laser use as a root planing complement in vitro
Nammour, Rocca JP, Keiani K, Balestra C, Snoeck T, Powell L, Reck JV.

The purpose of this study was to define the optimal irradiation conditions of a KTP laser during root planing treatment. METHODS: The surfaces of 60 single-root human teeth were scaled with conventional instruments before lasing. The pulpal temperature increase was measured by means of one thermocouple placed in the pulp chamber and a second one placed on the root surface at 1 mm from the irradiation site. The influence of variables of coloration by Acid Red 52 (photosensitizer), scanning speed, dentin thickness, and probe position was analyzed for a constant exposure time of 15 sec and 500 mw (spot size diameter, 0.5 mm). The pulpal temperature was below 3 degrees C for the adjustments.

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2004 Jul 1
A deep stop during decompression from 82 fsw (25m) significantly reduces bubbles and fast tissue gas tensions
Marroni A., Bennett P.B., Cronjè F.J., Cali-Corleo R., Germonprè P., Pieri M., Bonuccelli C., Balestra C.

In spite of many modifications to decompression algorithms, the incidence of decompression sickness (DCS) in scuba divers has changed very little. The success of stage, compared to linear ascents, is well described yet theoretical changes in decompression ratios have diminished the importance of fast tissue gas tensions as critical for bubble generation. The most serious signs and symptoms of DCS involve the spinal cord, with a tissue half time of only 12.5 minutes. It is proposed that present decompression schedules do not permit sufficient gas elimination from such fast tissues, resulting in bubble formation. Further, it is hypothesized that introduction of a deep stop will significantly reduce fast tissue bubble formation and neurological DCS risk. A total of 181 dives were made to 82 fsw (25 m) by 22 volunteers. Two dives of 25 min and 20 min were made, with a 3 hr 30 min surface interval and according to 8 different ascent protocols. Ascent rates of 10, 33 or 60 fsw/min (3, 10, 18 m/min) were combined with no stops or a shallow stop at 20 fsw (6 m) or a deep stop at 50 fsw (15 m) and a shallow at 20 fsw (6 m). The highest bubbles scores (8.78/9.97), using the Spencer Scale (SS) and Extended Spencer Scale (ESS) respectively, were with the slowest ascent rate. This also showed the highest 5 min and 10 min tissue loads of 48% and 75%. The lowest bubble scores (1.79/2.50) were with an ascent rate of 33 fsw (10 m/min) and stops for 5 min at 50 fsw (15 m) and 20 fsw (6 m). This also showed the lowest 5 and 10 min tissue loads at 25% and 52% respectively. Thus, introduction of a deep stop significantly reduced Doppler detected bubbles together with tissue gas tensions in the 5 and 10 min tissues, which has implications for reducing the incidence of neurological DCS in divers.

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2004 Feb 1
Scuba diving can induce stress of the temporomandibular joint leading to headache
Balestra C., Germonpré P., Marroni A., Snoeck T.

In ordinary recreational scuba diving, many anatomical parts can be involved in disorders of cranial regions: ears and eyes are involved but also sinuses. Dental problems are generally involved in barotraumas because of bad dental fillings or other matters of interest to the general dental practitioner.

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2004 Jan 1
The Fractal approach as a tool to understand asymptomatic brain hyperintense MRI signals
Balestra C., Germonprè P., Marroni A., Farkas B., Peetrons P., Vanderschueren F., Duboc E., Snoeck T.

The prevalence of a Patent Foramen Ovale is described in merely 30% of the asymptomatic population. This patency has been shown to be an increasing risk factor for paradoxical cerebral embolization. Some desaturation or decompression situations in human activities such as scuba diving or altitude flight are prone to provoke embolisations.

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1998 Jan 1
Intrathoracic pressure changes after Valsalva strain and other maneuvers: implications for divers with patent foramen ovale
Balestra C., Germonpré P., Marroni A.

Scuba divers with patent foramen ovale (PFO) may be at risk for paradoxical nitrogen gas emboli when performing maneuvers that cause a rebound blood loading to the right atrium. We measured the rise and fall in intrathoracic pressure (ITP) during various maneuvers in 15 divers. The tests were standard isometric exercises (control), forceful coughing, knee bend (with and without respiration blocked), and Valsalva maneuver (maximal, gradually increased to reach control ITP, and as performed by divers to equalize middle ear pressure). All the maneuvers, as well as the downward slope of ITP at the release phase, were related to the control value.

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