Efficacy of low doses of radioiodine in the treatment of autonomous thyroid nodules: importance of dose/area ratio.

Radioiodine (131I) represents an interesting alternative to surgery in the treatment of autonomously functioning thyroid nodules (AFTN), but leads to a significant incidence of hypothyroidism when high doses are used. Over 4 years, we have treated 40 patients (hyperthyroid [Plummer's disease]: 6, single hot nodules with undetectable thyrotropin [TSH] and normal serum free thyroxine [FT4]: 34), 34 single hot nodules with undetectable thyrotropin TSH and normal serum free thyroxine [FT4] with 131I. The dose level was neither related to the concentration of FT4 nor to the iodine uptake on thyroid scintigram. Retrospectively we measured the nodule's area on the scan and calculated the dose/area ratio (DAR). Three months after treatment, 30 patients were euthyroid, 9 were still hyperthyroid, and 1 was hypothyroid. The mean DAR of the euthyroid patients was twofold higher than for the hyperthyroid subjects (1.4 +/- 0.8 vs. 0.7 +/- 0.3 mCi/cm2; p = .003) and one-half the DAR for the hypothyroid patient (2.82 mCi/cm2). Twenty of the 30 euthyroid patients had received a dose higher than 1 mCi/cm2 and 7 of 9 hyperthyroid patients had received a dose lower than 1 mCi/cm2. (chi2 = 12.9; p = .02). The initial values of T4, TSH, and dose level of patients who were euthyroid or hyperthyroid at 3 months were not different. These data suggest that the efficacy of 131I for treating AFTN depends on the DAR, rather than the initial T4 value or the 131I uptake. A DAR between 1 and 1.5 mCi/cm2 seems to be optimal and avoids hypothyroidism.

[Severe coronary events and corticoids bolus. An update apropos of 3 new cases]. / Accidents coronaires graves et bolus de corticoïdes. Mise au point à propos de trois nouvelles observations.

The authors report two new cases of angina and/or myocardial infarction and one sudden death after an infusion of a bolus of high dose steroids. Coronary spasm, demonstrated in one of the cases and highly probable in the other two, is proposed as the mechanism of ischaemia. The authors underline the importance of the underlying pathology, previous coronary history, and the modes of administration. This type of treatment is often essential in clinical medicine and therefore the potentially severe secondary effects must be understood. Therefore, a previous history of myocardial infarction constitutes a definitive contra-indication and the duration of injection must be over one hour for doses greater than 250 mg. In all cases, a detailed medical history and an ECG are essential before starting treatment.

[Periaortic fibrosis with pericardial and perirenal involvement: apropos of a case]. / Fibrose périaortique avec envahissement péricardique et périrénal: à propos d'un cas.

The authors report a case of right ventricular insufficiency by constrictive pericarditis revealing aortic and retroperitoneal fibrosis. Only one similar case has been published. We discuss the etiology of this affection, the possible analogies with idiopathic systemic fibrosis and Takayasu's disease and the possible participation of thyroiditis disease and therapy (particularly propranolol).

[Acute pituitary necrosis after multiple pituitary stimulation test]. / Nécrose hypophysaire aiguë après test de multistimulation hypophysaire.

Iatrogenic necrosis of the pituitary gland is well-known but rarely caused by stimulation tests used to investigate pituitary adenomas; 26 cases have been reported in the literature. We report 2 new cases where the chronology of the events suggests the sudden necrosis resulted from stimulation tests. Several mechanisms have been proposed. It is not possible to define increased risk as a function of the adenoma histology. In most cases, voluminous tumors are revealed by visual dysfunction. These accidents should not overshadow the role of function tests in neurosurgical situations. Outcome is usually favorable after acute necrosis.