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B Le Bihan

Publications and source records attributed to B Le Bihan.

4 recordsLinked to original sources

[Results of ultrasonographic and cytologic follow-up of 311 initially non-suspicious thyroid nodules].

The follow-up of initially non suspect thyroid nodules after fine needle biopsy is not completely worked out. Since 1985, we have entered upon a prospective study concerning the followup of thyroid nodules supposed to be benign after initial evaluation. What are the nature and the frequency of means to be used for their follow-up? Three hundred and eleven nodules are followed up on a mean duration of 2.44 years. The follow-up of 65 of them is 4 years or more. The follow-up of 120 others is 3 to 4 years; 197 nodules are followed up during 2 to 3 years. A physical examination, an ultrasonography completed with a fine needle biopsy or an ultrasonically guided fine needle biopsy are worked out every year. Twenty-three per cent of initial biopsies are non significant and 90% of them are ultrasonically guided biopsies. At the end of the study, the repeating biopsies reduce to 6% the non significant biopsies ratio. Four histological thyroid cancers are detected in three female patients 1 year, 2 years and 5 years after the initial evaluation. Ultrasound alterations of nodules are observed in case of very suspect biopsies. Ninety-six per cent of the followed up thyroid nodules remain not cytologically suspect. These findings allow us to propose the following guidelines for the assessment of a non suspect thyroid nodule: half-yearly or yearly physical examination, yearly or biennial ultrasonography, repeat biopsy after 2 or 3 years when clinical or ultrasound suspect modification is wanting.

Adolescent↗

[Transient variations of alveolar gas composition during haemodynamic disturbances (author's transl)].

Passive changes in the posture induce haemodynamic disturbances, and especially a decrease of the cardiac output. This in the steady state does not involve any modification of the alveolar gas. There are however transient variations of PAO2 and PACO2, studied in this work at constant states of ventilation and metabolism. The haemodynamic disturbances are produced by a tip-up seat, actuated by a sinusoidal motion to different velocities and a constant amplitude (90 degrees). The frequency response is analyzed according to servosystems theories. The results show that there are causes of non-linearity in PAO2 and PACO2 variations, more complex for PAO2, and that the amplitude of the variations is two to three times greater for PAO2 than for PACO2. The observed transient phenomena are essentially interpreted as resulting from the differences in dynamic behavior between cardiac output on the one hand, variations in the arterio-venous gradient on the other; this effect is more pronounced for PAO2 variations. From a practical point of view, the great amplitude of transient PAO2 variations (as much as 11 mmHg) could, under certain conditions, allow, by the single continuous recording of PO2 to the mouth, to demonstrate and define the time of the arrival of an haemodynamic disturbance in patients with assisted ventilation.

Blood Circulation↗