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Biparietal diameter growth differs considerably in the twin gestation compared to the singleton gestation; thus the use of a specific standard is recommended. A shift toward lower values is noticed in monochorial twins. In the case of the abdominal diameter growth, instead, no significant difference is found between twins and singletons.
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The thyroid morphology, histology, biometry and its anatomical connections are studied during the whole embryonic life in the small spotted dogfish (Scyllium canicula Cuv.). The first differentiation of the gland appears as a thickening of the pharyngeal floor, containing PAS inclusions, at stage 10 mm. The first follicles are apparent at stage 30 mm. The thyroid volumetric relative growth is studied during the whole development and is compared with the absolute embryonic length growth. Volumetric variations of the hypophysis upper parts and ventral lobe are also studied during the whole embryonic life.
The effect of pilocarpine hydrochloride on the anterior chamber depth and lens thickness was measured in 20 eyes of patients with chronic open-angle glucoma who were receiving long-term glaucoma therapy with pilocarpine. Measurements were made with high-resolution ultrasonic biometry. This study demonstrated that regardless of their age (58.4 years, average) and the fact that they had been regularly using pilocarpine from two to four times a day, 85% of these patients demonstrated narrowing of the anterior chamber (AC) depth (average, 0.19 mm) and thickening of the lens (average, 0.21 mm) with each instillation of pilocarpine. In approximately 15% of eyes, a repeatable deepening of the AC depth and flattening of the lens was noted.
Editing options of an interactive graphical-biometry statistical system are described. A method for screening using a highly reduced data file is illustrated. By utilizing properties of sample Fourier coefficients, the problem of component overlap can be resolved. This, in turn, tends to free edited statistical information from the contamination or truncation inherent in the usual screening process.
14 national groups have collaborated under WHO auspices to select, from local defined populations of individuals with clinical diabetes, groups of approximately 500 within the age range 35--55 yr stratified by age, sex, and known duration of diabetes. In each center, the selected patients were submitted to a standardized study protocol, which included systematic inquiry (WHO questionnaire) for the presence of symptoms of angina pectoris, history of myocardial infarction, presence of intermittent claudication, and cigarette smoking history. Examination included standard biometry, blood pressure measurement, 12-lead (centrally Minnesota coded) electrocardiography, and central laboratory measurement of serum cholesterol and creatine. Ophthalmoscopic and urinary examinations were also included. The prevalence of arterial disease symptoms and electrocardiographic abnormalities show very large variation between countries, the lowest rates generally being found in the Oriental samples and the highest in the European. "Risk factors" for arterial disease (blood pressure, serum cholesterol, and cigarette smoking) also vary widely between diabetic groups. Although data are not yet complete, these differences appear unlikely to explain the variation in the atherosclerotic morbidity observed. Diabetic women were at least as vulnerable to arterial disease as diabetic men. A high prevalence of nonspecific abnormalities of the repolarization phase of the ECG was found, even in groups where ischemic abnormalities were rare. The origin of these is uncertain; they may represent variable local changes or possibly diabetic cardiomyopathy. This preliminary report confirms and quantifies previous indications that the impact of atherosclerotic disease on persons with diabetes varies considerably between national groups, in broad terms, running parallel with the variations in prevalence in the populations in general and suggesting that cultural and/or ethnic factors are more important determinants of atherosclerosis in diabetic individuals than is the diabetic state per se.
The rate of utero-placental blood flow depends on functional components (perfusion pressure and flow resistance within the area of the vascular bed of the placenta), as well as on morphological factors (regressive changes in the placenta). Different primary maternal conditions and diseases may lower the rate of placental flow, leading to placental insufficiency; the highest percentage, by far, of placental dysfunction is found in patients suffering from gestosis. Hypocirculation initially present in cases of EPH gestosis and caused by arteriolar spasms triggers off a vicious circle involving placental infarction and severe reduction in the utero-placental perfusion rate. This in turn leads to fetal hypotrophy, a high rate of premature births and perinatal mortality. Verification of HPL, HCG, alpha-Fetoprotein or E3 in maternal serum and amniotic fluid or urine greatly improved the recording of partial placental functions. Along with ultrasonic biometry, cardiotocography and amnioscopy, these hormonal parameters allow only indirect assessment of the placental function. On the other hand, measurements of the utero-placental flow offers a direct approach. In order to evaluate the placental flow measurements it is imperative to obtain a curve indicating the course over the last third of the pregnancy-in addition to establishing a general normal range. In case of placental insufficiency, it is necessary to determine whether this is due to functional disorders alone, or to more extenisve morphological changes. A placental perfusion test (PPT) was developed in order to make this distinction. Beta2-mimetic treatment is indicated if functional factors predominate, whereby it appears essential to obtain the requisite experimental data for precise quantification of beta-mimetic action.
A 59-year-old women with no previous history of diabetes mellitus was admitted in diabetic ketoacidosis. Ultrasonic biometry was used to measure axial vitreous length during therapy. Vitreous length increased from 14.09 mm shortly after admission to 14.26 mm (p less than 0.05) when the episode of diabetic ketoacidosis cleared. An interesting finding was the presence of a horseshoe-shaped retinal tear after the patient was discharged. Severe dehydration with resultant shrinkage of the vitreous compartment may provide sufficient vitreoretinal traction to cause a retinal tear. In addition, an estimate of volume change showed a comparable decrease in vitreous volume seen with therapy using osmotic agents measured in rabbits.
The structure of different components from lumbar ganglia of the cat sympathetic trunk were studied in norm and 6h after intramuscular administration of prednisolone (5 mg/kg). Paraffin sections were stained with azocramine after Heidenhain, Wallart and Houette, azure II -- eosin. Biometry of different ganglial structures was performed by G.G. Avtandilov's dotted method. It was demonstrated that as a response to prednisolone administration, certain morphological changes appeared in all ganglial components. The walls of capillaries grew thicker, endothelial nuclei protruded into their lumen. Collagenous fibres of the connective tissue capsule and ganglial stroma grew thicker and acquired twisted appearance, the amount of the basilar substance increased. Simultaneously, there was a sharp increase of the nuclear section area in perineuronal ganglia. The total area of neuronal sections in the ganglia also increased at the expense of both increasing area of neuronal cytoplasm and hypertrophy of their nuclei.
Scientific knowledge is reliable because it has been built on accurate measurements. Clinical knowledge is not. The science of biometry was started in 1835 by the Belgian astronomer Adolphe Quetelet. In the last fifty years a precise set of rules have been invented for this science. The method is suitable for a wide range of problems in clinical medicine and as the result of its application in recent years a firm foundation has been laid upon which scientific clinical knowledge can be built. Surge-ns, particularly, have been slow to apply biometrical methods to their clinical problems; but a start has now been made. The outcome of a particular type of treatment is determined by a complex set of inter-acting factors. The basis of the appropriate biometrical method is the elimination of all bias in favour of one of the rival techniques being compared. If this precaution is taken the observed results of the trial can be fitted onto Quetelet's distribution graph, and the probability of the observed difference in the results being due to chance, and nothing else, can be measured mathematically. The accuracy of this measurement deteriorates the greater are the number of the patients who can not be found and examined at the end of the trial. To make this point two trials conducted by the author are used. In the trial designed to discover if postoperative deep vein thrombosis and pulmonary embolism could be prevented by electrically stimulating the patients legs during the operation there was no difficulty. All the patients were examined at the end of the trial, because it ended before any of the patients left the hospital. The trial to discover if the primary treatment of varicose veins ought to be by Fegan's sclerotherapy or by operation was the exact opposite. At the end of the first year of the two year trial 15% of the patients could not be traced. The results in these patients, therefore, was unknown. Because of this, elaborate mathematical calculations had to be made to try and reach a reliable conclusion to the trial. The loss of patients before the end of the trial is a very serious practical difficulty which besets all long-term clinical trials.
For some time it has been recognized that abnormal intrauterine development can lead to dissociation between maturity and external size and/or weight of the fetus. The results of pathophysiological and biochemical studies of fetal growth and nutrition have resulted in attempts to monitor and time every pregnancy at risk. The most recent information in the area of intrauterine development has shown that also organic and functional maturity of fetal organ systems can develop dissociated from gestational age. This observation points out the necessity for additional measures in order to achieve the goals of Planed obstetrics. The possibilities of ultrasound biometry for determining gestational age were presented. Taking normal and abnormal fetal growth and behavior into consideration, the use of ultrasonic diagnostic methods makes it possible to acquire concrete data regarding the size and maturity of some fetal organ systems. The methodological problems such as arise in clinical practice were explained and discussed in light of the most recent developments in equipment.
A statistical assessment of several "randomized" clinical trials was carried out and the following conclusions were noted. 1. There is no statistically significant evidence that radiation to the peripheral lymphatics and/or chest wall following radical mastectomy affects survival. 2. There is significant evidence that postoperative irradiation to the peripheral lymphatics and/or chest wall does decrease local recurrence rate. 3. There is reliable evidence that the treatment of local recurrence, once it develops, is successful in only 50% of the cases. 4. There is evidence that radiation plus simple mastectomy is as effective in the treatment of breast cancer as radical mastectomy alone. It is our considered opinion that radiation remains a useful adjuvant and complementary agent in the treatment of breast cancer, is not harmful vis a vis survival and should be used when and where indicated.
The ultrastructural features of the adrenergic nerve fibers in the pineal glands of the rat, ground squirrel and chinchilla are described. Frequency distribution histograms of diameters of granulated and non-granulated vesicles in the adrenergic nerve endings demonstrate that the pineal nerve endings in the chinchilla contain a considerable number of large granulated and non-granulated vesicles, in contrast to those in the rat and ground squirrel. Synaptic ribbons seen in the pinealocytes of the ground squirrel were often localized near that plasma membrane which lay in close proximity to the axolemma of adrenergic nerve fibers. This observation may indicate that the synaptic ribbons are involved in the functional interconnection between pinealocytes and adrenergic nerve fibers. Localized dilations of the adrenergic nerve fibers were commonly observed in the pineal glands of all species examined. In addition to a variety of axonal constituents, various forms of inclusion bodies were tightly packed within these axonal dilations. The accumulation of the inclusion bodies may represent degenerative changes which occur in the pineal adrenergic nerve fibers in relation to the functional activity of the pineal gland.