Incidence of abnormal cerebral findings in the MRI of clinically healthy divers: role of a patent foramen ovale.
BACKGROUND
To investigate incidence and number of abnormal cerebral hyperintensities (ACFs) in Magnet Resonance Imaging (MRI) and its relation to a patent foramen ovale (PFO) in divers with no history of decompression illness.


METHODS
Cohort study on 50 divers (21-5500 dives).


METHODS
Incidence and number of ACFs visualized by cranial MRI and presence and size of a PFO as documented by echocardiography and transcranial Doppler ultrasound (TCD) with echocontrast.


RESULTS
A total of 137 ACFs was found in the 50 subjects, with a significant correlation between the number of dives and number of ACFs (r = 0.28; p < 0.05); but after correction for age, the remaining correlation (r = 0.15) did not reach significance. In 18 divers, a PFO was present by either the application of echocardiography or TCD; in 12 divers, the PFO was of high hemodynamic relevance. Ten of 18 divers with a PFO had at least one ACF, while in the remaining 32 divers, only 14 had at least one ACF (56% versus 44%, p = NS). Seven of 14 divers (50%) with 4 ACFs had a PFO, compared to 11 of 36 (31%) with less than 4 ACFs (p = NS).


CONCLUSIONS
In this cohort of healthy divers, in contrast to an earlier report, no significant association was found between PFO presence and incidence or number of ACFs.
German Naval Medical Institute, Kiel-Kronshagen, Germany.
A E
AE
Koch
J
J
Kampen
K
K
Tetzlaff
M
M
Reuter
P
P
McCormack
P W
PW
Schnoor
N
N
Struck
L
L
Heine
I
I
Prytulla
H
H
Rieckert
D000328:Adult; D020520:Brain Infarction / Q000175:diagnosis / Q000473:pathology*; D015331:Cohort Studies; D004242:Diving; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008279:Magnetic Resonance Imaging; D008297:Male