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At least 1,189 records · Page 66Linked to original sources

PubMed1994

Mechanism and etiology of primary chronic angle closure glaucoma.

The ocular anatomic features, pupil-blocking force, status of angle synechiae closure and positivity of provocative tests were compared between the primary chronic angle closure glaucoma (PCACG) and primary acute angle closure glaucoma (PAACG) by using ultrasonic biometry, computerized anterior ocular segment image processing technique, gonioscopy and provocative tests. The studies showed that the anterior chamber depth of PAACG were shallower than that of PCACG; the pupil-blocking force of PAACG was stronger than that of PCACG; the status of angle synechiae closure of PCACG were mainly creeping synechiac closure; the positivity of mydriasis test was much higher (46.01%) in PCACG than that (6.8%) in PAACG after iridectomy. These facts suggest approximately half of the PCACG cases may be mult-mechanism to contribute to the angle closure besides the mechanism of pupillary block. Therefore, the authors emphasis that the pupillary block must be eliminated as well as the other mechanism for the treatment of PCACG and finally, a criteria of diagnosis and principles of management of PCACG were proposed.

Adult↗

PubMed1994

Sonographic prenatal diagnosis of heterozygous achondroplasia: a case report.

A case of heterozygous achondroplasia diagnosed prenatally by sonographic examination at third trimester, demonstrating a large head, frontal bossing, low nasal bridge, shortening of the long bones (rhizomelic form), was presented and confirmed by neonatal physical examination and radiograph. Sonography has become the most sensitive and accurate method for detection of this abnormality. It displays the fetal biometry without distortion and permits accurate prenatal diagnosis. However, the prenatal diagnosis of this abnormality is very difficult until the third trimester of pregnancy.

Achondroplasia↗

PubMed1994

Prenatal diagnosis of major congenital malformations.

Congenital malformations affect approximately 2-3% of all live births every year. Several of these are associated with in-utero fetal demise or may account for significant neonatal morbidity and mortality. Therefore, it is important that, when possible, congenital anomalies are diagnosed during the antenatal period to allow adequate counseling of the mother and to permit preparation of the neonatal care team to optimize the outcome. The role of ultrasound in perinatal medicine has expanded over the past two decades. Previously, B-mode sonography allowed for the detection of multiple gestations, fetal biometry, and basic antenatal diagnosis of congenital anomalies. The technology has since rapidly advanced to the point that even subtle abnormalities are amenable to antenatal diagnosis. Perinatal medicine has advanced concurrently with these technological breakthroughs, and as a result, the possibilities for in-utero therapy and potential surgery have markedly improved. This article reviews the types and incidences of the various anomalies that are detectable by antenatal ultrasonography using a systematic approach; highlights the prenatal diagnostic and therapeutic strategies; discusses the obstetrics and medical management of pregnancies complicated by these conditions, and presents the neonatal prognosis and the recurrence risks for subsequent pregnancies.

Congenital Abnormalities↗

PubMed1994

Familial nanophthalmos: management and complications.

Nanophthalmos is a rare form of congenital hypermetropia, in which, the individual is at a high risk of developing angle-closure glaucoma. We report a family of nanophthalmos affecting a brother and sister, as confirmed by biometry. Genetic analysis revealed an autosomal recessive mode of inheritance. The sister developed angle-closure glaucoma, which was refractory to medical and laser therapy. She underwent surgical interventions which resulted in complications. The clinical presentation, management, and complications encountered are discussed.

Adult↗

PubMed1994

Color Doppler evaluation of uteroplacentofetal circulation in management of high risk pregnancies.

The study group consisted of 75 high risk singleton pregnancies in whom color duplex Doppler evaluation of the uteroplacental circulation was determined and correlated with perinatal outcome. Uterine, umbilical and middle cerebral artery flow velocity waveforms (FVW) were analysed and the resistance index (RI), pulsatility index (PI) and the systolic/diastolic (S/D) ratios measured. On the basis of the FVW the uteroplacentofetal blood flow was classified as normal, increased resistance to flow, absent end diastolic flow (AEDF), and reversed end diastolic flow (REDF). Ultrasound biometry was simultaneously performed for all fetuses, while non stress testing was performed as and when indicated. Of the 75 fetuses studied 33 (44%) had abnormal FVWs and only 30.3% of these had an uncomplicated outcome as compared to 81% of those with normal flows. The mortality in cases with abnormal flows was 43% as compared to 7% in those with normal flows. There were 40 growth retarded fetuses in the study group of which 30 (75%) had abnormal umbilical artery FVWs. Of the 18 fetuses with AEDF or REDF, all (n = 7) in whom timely obstetric intervention was not done died in utero, irrespective of fetal weight and gestational age, however 75% of these with weight > 1000 g survived when delivered by cesarean section.

Female↗

PubMed1976

Clinical trials in surgery.

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.

Clinical Trials as Topic↗

PubMed1994

[Postoperative refraction and anterior chamber depth after complicated cataract operation with vitreous loss and transscleral posterior chamber lens fixation].

The accuracy of preoperative biometry was tested in patients with transscleral suture fixation of the posterior chamber lens. Postoperative refraction and anterior chamber depth of 34 eyes that had been subjected to complicated cataract extraction with vitreous loss were compared with those in 17 fellow-eyes in which uncomplicated cataract extraction had been performed. The anterior chamber depth was significantly deeper after transscleral suture fixation of the posterior chamber lens (mean 0.59 mm, P < 0.05). The refraction differed by +0.68 D between transscleral suture fixation and the control group. We recommend that +0.5 D should be added to the calculated intraocular lens power if transscleral suture fixation becomes necessary during cataract extraction.

Aged↗

PubMed1993

[Critical corneal radii may skew correct IOL calculation by using the SRK/T formula].

The popular SRK/T formula for IOL calculation is analysed with respect to the underlying optical model and identified as a "thin-lens formula". As far as the prediction algorithm for the "optical anterior chamber depth" is concerned, it is shown that mathematically there exists a critical value for the radius of corneal curvature which marks the onset of a nonphysiologic formula behaviour. Within the algorithmic framework of the SRK/T formula, this critical curvature is solely dependent on the axial length. Clinically, the effect of this insufficiency of the formula is not of great importance: a check through our biometry database showed that 4 out of every 1000 IOL calculations were affected.

Algorithms↗

PubMed1994

[The estimation of fetal weight by measurement of the adipose tissue of the extremities. Use in the diagnosis of hypotrophy].

OBJECTIVE: To investigate the accuracy of small for age fetuses diagnosis by a new method of fetal weight estimation, in comparison with some others models. A retrospective study. SUBJECTS AND METHODS: From a 232 fetuses population, whom age is known, ultrasound measurement have been performed (BPD, TBD, FL, AC and thigh circumference). Three physicians collaborated to data collection. All measurement have been done within a 3 days duration between measuring and birth in order to compare actual and calculated weight. There are 39 small fetuses coming from 10th percentile (17.5%), between then 24 from 5th percentile. RESULTS: Positive predictive value (PPV) of small for age diagnosis (from 10th P) by our model is 74% with a 74% sensibility and a 94% specificity. With Warsof estimation model, the PPV is only 47% with a 71% sensibility and a 83% specificity (p = 0.001). COMMENTS: Limbs subcutaneous fat ultrasound measurement improve considerably fetal weight estimation quality (mean error = 6% vs 10% for most of the classical models) and, as an extension, small for age fetuses diagnosis. The cutaneous and subcutaneous circumferences, between which is situated fat tissue have a better individual correlation to actual weight than abdominal circumference, usually considered as the best trophicity parameter. CONCLUSION: High positive predictive value show long term predictive detection possibility. It appears that this diagnosis could be done earlier with a better accuracy that the classical ultrasound biometry.

Abdomen↗

PubMedDate not supplied

[Acute appendicitis. A clinicopathological analysis of 200 cases].

OBJECTIVES: a) to carry out a prospective study of 200 cases of acute appendicitis in adult patients; b) to correlate clinical, laboratory, radiological, and pathological findings. MATERIAL AND METHODS: clinical data were collected from all patients; every patient had hematic biometry, urine exam (UE), abdominal radiography, an histopathological study appendix. RESULTS: the patients were 98 males and 102 females; 66.5% were between 15 and 25 years old. All patients had abdominal pain, 56.5% nausea and vomit, 49% fever, 10.5% diarrhea, and 6% urinary symptoms. Post-operatory complications were seen in 24.5%. Leucocytosis greater than 10,000 was found in 82.5%, some alteration of UE in 45%, and abnormal radiography in 56.5%. Histopathological study showed simple appendicitis in 16.5%, hemorrhagic in 8%, purulent in 22%, hemo-purulent in 30.5%, an perforated in 21%. CONCLUSIONS: the diagnosis of appendicitis is basically a clinical one, since 17.5% showed normal white-cell count, and 43.5% normal radiography.

Acute Disease↗

PubMed1993

[Integration of Doppler ultrasound into the obstetric department of a gynecologic clinic].

This study was performed to evaluate the time interval for Doppler ultrasound and sonographic diagnostic measurement at 267 patients during antenatal risk screening. Time for biometry, screening of malformation, Doppler ultrasound, documentation and discussion with the patients were measured. Although experienced colleagues used an standardized inquiry a mean time interval of 52 minutes were needed under optimal conditions. It is interesting to note that outstanding disturbance factors extend the examination time considerable. Many data must be calculated and recorded by the obstetrician. Several proposals are drawn up and discussed in this paper on the basis of this results. This study shows that high special knowledge and a large time expense is necessary to establish Doppler technology in the routine antenatal screening.

Appointments and Schedules↗

PubMed1993

[The value of Doppler imaging of the aorta, carotid artery and middle cerebral artery in obstetric diagnostics].

The relation of blood blow in the fetal aorta and carotis is a marker for the well being of the unborn child. Increase of cerebral vascularity associated with decrease of blood flow in the aorta is a sign for a fetal risk situation. It is, however, of disadvantage that the fetal carotis is often difficult to image with an wedge-shaped angle between doppler beam and vessel. We therefore included screening of an intracerebral vessel (a. cerebri media) in order to find out whether examination of this vessel, much more easier to perform, may have a similar diagnostic value or be an even more sensitive prognosticator of fetal risk than the carotis. In two hundred and forty patients in the 29th to 40th week of gestation all these three vessels were scanned with the duplex system AI 3200, Dornier company, Germany. The result was correlated to sonographic biometry, birth weight, and mode of delivery. It could be proven that when analyzing individual findings, pathology in the risk groups is much higher, whereas mean values showed less marked differences between risk and control groups. Our results suggest that the a. cerebri media is a slightly more sensitive indicator of fetal risk, since in this vessel retrograde resistance can be detected earlier and is more evident. A combination between assessment of the aorta and a cerebral vessel, is however, the method of choice in cases of pathological findings in diagnosis of fetal well being, since only examination of a peripheral and a central vessel results in an exact diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗

PubMed1993

Ultrasonic evaluation of the lens thickness to axial length factor in primary closure angle glaucoma.

Ultrasonic biometry was done in 232 normal eyes and 138 eyes with primary angle closure glaucoma (ACG), using Ultrascan Digital B System IV (10 MHz). The ratio between the lens thickness and the axial length (lens thickness to axial length factor, LAF) was evaluated as a biometric index for assessing the eye with primary ACG in Chinese. LAF of 2.00 was found to be ideal point of demarcation between ACG and normal eyes (i.e., lens thickness equals to 1/5 of axial length). It appears that LAF is helpful in screening primary ACG eyes from eyes of the general population. This is similar to the anterior chamber depth of 2.5 mm which is recognized as a threshold for the occurrence of primary angle closure glaucoma.

Adult↗

PubMed1993

[Diurnal variation of active movements: an indication of fetal hypotrophy?].

In a prospective study of 36 pregnancies, the authors made use of the mother's counting of active movements in order to evaluate the correlation between daytime fluctuations in active movements and fetal hypotrophy. With a threshold peak mean evening motor activity no more than 20 p. cent greater than in the morning throughout the period counted, daytime variations were found to have optimal diagnostic capacity for hypotrophy. During the last week preceding delivery, a threshold mean peak evening active movements no more than 35 p. cent greater than in the morning yielded optimum diagnosis of fetal hypotrophy. Furthermore, there was a correlation between daytime fluctuations in active movements and the findings of fetal ultrasound biometry and utero-umbilical flow velocimetry.

Anthropometry↗

PubMed1993

Prenatal detection of ischemic changes in the placenta of the growth-retarded fetus by Doppler flow velocimetry of the maternal uterine artery.

OBJECTIVE: To determine the relationships among the pregnancy outcomes of growth-retarded fetuses, Doppler flow velocimetry of the fetomaternal circulation, and pathologic changes in the placenta. METHODS: Forty-seven fetuses confirmed to be growth-retarded by ultrasonographic biometry were monitored during pregnancy in terms of the resistance indexes of the maternal uterine, fetal umbilical, and fetal middle cerebral arteries. After delivery, the placentas were examined for pathologic changes such as infarction and villous ischemia. RESULTS: Compared with 23 fetuses with nonischemic placentas, 24 growth-retarded fetuses whose placentas showed ischemic lesions were more frequently delivered preterm (P < .001) and by cesarean for fetal distress (P < .01), and they also had lower mean pH, higher carbon dioxide pressure, and lower oxygen pressure values (P < .05). Compared with the fetal umbilical and middle cerebral artery resistance indexes, the uterine artery resistance index showed the highest sensitivity (91.7%), specificity (78.3%), and positive predictive value (81.5%) for detecting placental ischemic changes. Linear discriminative analysis also showed that the uterine artery resistance index had the strongest correlation (P < .00001) with the placental ischemic changes. CONCLUSION: Ischemia of the placenta is associated with an adverse pregnancy outcome in growth-retarded fetuses. The placental ischemic changes can be detected using Doppler flow velocimetry. Measurement of the uterine artery resistance index might be useful for determining the clinical management of growth-retarded fetuses.

Adult↗

PubMed1993

[New approaches in the treatment of hypotrophic fetuses].

Hypotrophy or intrauterine growth retardation of the foetus associated with placental insufficiency still remains a serious obstetric problem. In the submitted paper the authors compare hypotrophic foetuses treated in 1989 and 1990 at the authors' clinic by conventional methods only (biometry, bed rest, CTG oestriol, glucose and possibly heparin) with a group of hypotrophic foetuses treated in 1991 and 1992 with magnesium and where the therapeutic effect was followed up by Doppler flowmetry. Based on the results, the demand to improve placental insufficiency by pharmacological induction and stimulation of specific placental enzymes is met perfectly by concomitant parenteral and oral magnesium administration to pregnant women.

Female↗

PubMed1993

[Clinical features of primary chronic angle-closure glaucoma].

43 cases (86 eyes) of primary chronic angle-closure glaucoma (PCACG) and 44 cases (77 eyes) of primary acute angle-closure glaucoma (PAACG) randomly selected, and 30 normal subjects (34 eyes) were performed ultrasonic biometry of anterior chamber depth, lens thickness and axial length of the globe. By a micrometer attached to the slip-lamp, the width of the anterior chamber angle entrance was also calculated. The clinical manifestations and the natural course of PCACG, including the morphology of the anterior chamber angle and the peripheral anterior synechiae (PAS) as well as the dynamic changes in aqueous outflow were investigated. It was found that there were significant differences in the biometric parameters of the anterior segment between PCACG and PAACG or normal eyes. Follow-up study of the early stage PCACG cases showed that topical miotics and/or peripheral iridectomy effectively prevented the formation of PAS and the progressive development of PCACG. The criteria for diagnosis and the principles for treatment of PCACG were stipulated. The pathogenesis of PCACG was discussed, and it was emphasized that minor attacks of PAACG and its progressive stage should not be confused with PCACG.

Adult↗

PubMed1993

Ear length in second-trimester aneuploid fetuses.

OBJECTIVE: To test the hypothesis that small ears have diagnostic value in detecting second-trimester aneuploid fetuses by ultrasound. METHODS: We prospectively studied 452 patients with singleton pregnancies undergoing ultrasound examination for genetic amniocentesis at 14-25 weeks and an additional 30 singleton pregnancies at 20-25 weeks with a negative anomaly screen. Standard fetal biometry measurements were obtained, including ear length (from helix to end of lobe). RESULTS: Of these patients, 424 (88%) had ear measurements obtained, and a nomogram for ear length by gestational age was compiled. The relationship between ear length and gestational age was linear across the second trimester (r = 0.84, P < .001). Fourteen fetuses had aneuploidy by amniocentesis, of whom ten had ear lengths at or below the tenth percentile. The sensitivity was 71% and the specificity 92% (377 of 410). Positive and negative predictive values were 23% (ten of 43) and 99% (377 of 381), respectively. CONCLUSION: Fetal ear length may be useful in identifying aneuploid fetuses sonographically during the second trimester.

Aneuploidy↗