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.
Koch
A E
AE
German Naval Medical Institute, Kiel-Kronshagen, Germany.
Kampen
J
J
Tetzlaff
K
K
Reuter
M
M
McCormack
P
P
Schnoor
P W
PW
Struck
N
N
Heine
L
L
Prytulla
I
I
Rieckert
H
H
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