[Catheterization of the inferior petrosal sinus. Its role in the diagnosis of Cushing's syndrome. Experience with 23 explorations]. / Le cathétérisme des sinus pétreux inférieurs. Sa place dans le diagnostic du syndrome de Cushing. Expérience de 23 explorations.

Selective catheterization of the inferior petrosal sinus has been performed in 23 patients: 11 Cushing's disease, 5 lung carcinoid tumors whose diagnosis has been confirmed by surgery and 7 ACTH-dependent hypercortisolism whose final diagnosis has not yet been proved. The pituitary origin of hormone secretion is accepted if the central-to-peripheral ratio (C/PR) is equal or greater than 2 on basal values and/or during CRF test. On basal values, all subjects but one with confirmed pituitary lesions exhibited a C/PR > or = 2; the carcinoid tumors never exceeded the value of 1.3. After CRF injection, all the pituitary tumors showed an increase in C/PR; one patient with a lung carcinoid tumor (CRF-negative) showed a pituitary ACTH secretion (C/PR = 3.7). The localization of pituitary adenoma by the lateralization of hormone secretion is disappointing, except, perhaps, for very small extremely lateral adenomas. No accident occurred in our series, nor in the literature. This investigation seems the most reliable approach to prove the pituitary origin of hormonal hypersecretion. We recommend it to be performed in ACTH-dependent Cushing's syndrome when the secretory pattern is not typical and/or pituitary imaging is normal.

Three-dimensional reconstruction in routine computerized tomography of the skull and spine. Experience based on 161 cases.

Three-dimensional (3D) reconstruction in routine computerized tomography (CT) presupposes that the referring clinicians are motivated, software programs are of good quality, a second working console is available and manipulations are made by experienced persons. Maxillofacial surgery is the main, conventional indication, but the method is also used to plan the surgical treatment of craniofacial malformations and that of injuries and tumours. 3D reconstruction cannot replace a thorough analysis of the acquisition sections since its spatial definition is not as good as theirs. Without competing with pure research-work, a number of applications remain in the realm of speculative imaging, but it cannot be denied that 3D reconstruction has an interesting potential for teaching.

[Three-dimensional imaging in plastic surgery. Application to the carpal bones and skull]. / L'imagerie en trois dimensions en chirurgie plastique. Application au carpe et à l'extrémité céphalique.

Since 1987, the authors have developed three-dimensional (3D) imaging of the carpus. This new application of imaging allows spatial visualization of the complex shapes of the carpal skeleton from all angles and from all illuminations. The development of this technique should lead to a better understanding of the intimate physiology of the carpus, allowing the construction of a model of the wrist enabling precise planning of operative procedures. It also helps to elucidate complex pathological images which are sometimes difficult to interpret on computed tomography scans. In parallel, the same process has been developed for the skull. It is particularly useful in cranio-facial surgery, especially in congenital deformities. Progress in this technique should allow surgical simulation on a video screen in the very near future.

Clapping or percussion causes atelectasis in dogs and influences gas exchange.

We examined the effects of 10 min of lower lateral chest wall percussion with a mechanical percussor or hand clapping in groups of anesthetized, paralyzed, and ventilated supine dogs. Mechanical percussion was applied at 10-16 Hz and caused an esophageal pressure swing (delta Pes) of 10-17 cmH2O. Hand clapping was applied at 4-7 Hz and caused a delta Pes of 6-17 cmH2O. At necropsy there were large reddened areas on the lateral surface of the underlying lung as well as smaller reddened areas on the hilar surfaces of both lungs and on the lateral surface of the opposite lung. These reddened regions were demonstrated to be atelectatic by postmortem lung inflation (which caused the reddened areas to disappear) and by microscopic examination. Despite the atelectasis, gas exchange improved toward the end of the percussion or clapping period. In four dogs that were ventilated for an additional 20 min after percussion, there was a tendency for gas exchange initially to worsen and then to gradually improve.