MR imaging of the nasopharynx and floor of the middle cranial fossa. Part I. Normal anatomy

The normal anatomy of the nasopharynx and floor of the middle cranial fossa was analyzed with magnetic resonance (MR) imaging. MR images from five healthy volunteers were correlated with whole-organ cryomicrotome sections from three cadavers. Anatomic connections exist between the paranasopharyngeal spaces and the surface structures of the skull base. These anatomic connections include the intimate relationship between the eustachian tube and the pharyngobasilar fascia, the attachment of the muscles of mastication and deglutition to the skull base, and vascular and nervous structures in the foramina. The inherent contrast between the soft tissues of the nasopharynx and related structures and the bone of the floor of the middle cranial fossa allowed excellent visualization of these anatomic connections.     

Preoperative Saphenous Vein Mapping for Coronary Artery Bypass

Saphenous vein mapping by real-time duplex ultrasound scanning allows for the confirmation of the presence of patent vein and determination of the anatomical course of the vein prior to aortocoronary bypass procedures. This technique has proven to be of value in patients whose veins are not evident by physical examination and in those whose length of conduit may be limited by previous vein stripping or thrombophlebitis.     

Atrial fibrillation with neonatal pulmonary lymphangiectasia

A female infant born at 28 weeks' gestation was found to have mild hydrops foetalis. Initial echocardiography showed a structurally normal heart. During the first week of life, episodic atrial tachycardia with 1:1 or 2:1 conduction was seen, requiring therapy with digoxin. The infant remained ventilator dependent, with a persistent, chylous pleural effusion which contained a preponderance of lymphocytes. Congenital pulmonary lymphangiectasia (CPL) was confirmed histologically. Worsening episodes of atrial tachycardia, including episodes of atrial fibrillation, were further investigated and a repeat echocardiogram revealed thickening of the entire right atrial wall. The cardiac findings of a thickened right atrial wall with the histological signs of myocarditis were thought to be the cause of paroxysms of atrial fibrillation, an extremely rare arrhythmia in the neonatal period. To the authors' knowledge there have been no previous reports of CPL in association with the cardiac abnormalities described herein.     

Treatment by hGH of Constitutional Delay of Growth and Adolescence

ABSTRACT. In constitutional delay of growth and adolescence (CDGA), all growth and maturation parameters are delayed by 2–4 years. Provocation tests of hGH secretion give normal values, but spontaneous (endogenous) secretion is low. This can be assessed by measuring night-time hGH secretion, when the differences between normal subjects and CDGA patients are highly significant. Replacement therapy with hGH produced growth spurts in all but one patient, improving their growth prognosis. A new series of 16 CDGA patients has now been treated with hGH for 1–3 years. Catch-up growth was seen during the first year, which decreased to normal growth velocity by the third year. This normal growth rate is still faster than the pretreatment velocity. Although hGH therapy may be effective in CDGA, it may only be justified in cases with psychological problems arising from their short stature.     

Postnatal Survival in Wistar Rats following Oral Dosage with Zidovudine on Gestation Day 10

Postnatal Survival in Wistar Rats following Oral Dosage withZidovudine on Gestation Day 10. GREENE, J. A., AYERS, K. M.,DE MIRANDA, P., AND TUCKER, W. E., JR. (1990). Fundam. Appl.Toxicol. 15, 201–206. Groups of 20 female Wistar ratsfrom Charles River Breeding Laboratories (Kingston, NY) weregiven three oral doses of 100 mg zidovudine/kg at 5-hr intervalson Gestation Day 10 (total dose = 300 mg/kg). Control rats receivedthree oral doses of the vehicle, distilled water. This designapproximated that of an earlier study that reported 38% postnatalmortality among the offspring of Wistar rats given zidovudine.In the study reported here, no adverse effects were noted onmaternal body weight, food consumption, reproductive capacity,or hematology. Similarly, no effects on growth or survival ofthe offspring were noted. Hematology and clinical chemistryvalues were comparable between offspring of treated and controldams, and no treatment-related gross or histopathologic lesionswere noted in the weanling rats. The mean concentration of zidovudinein embryonal homogenates, collected 30 min after administrationof the third dose to the dam on Gestation Day 10, was 21.1 µg/gtissue. This value is approximately one-third of the mean drugplasma concentration (62.6 µg/ml) measured in the thmsat the same time point. The dramatic difference in results inthe two studies may be related to differences in Wistar ratsfrom two different sources or to other unknown factors associatedwith the design and conduct of the studies. The results of thecurrent study were consistent with other preclinical studieson the reproductive toxicity of zidovudine in rats and rabbits.