Ectopic Pregnancy — Potentials for Diagnosis Using Ultrasound and Urine and Serum Pregnancy Tests

The ultrasound findings from 260 patients with a clinical suspicion of ectopic pregnancy have been analysed and correlated with the results of urine pregnancy tests and tests of serum LH and/or HCG levels. Most importantly in a practical clinical context, it was found that a negative serum test virtually excludes an ectopic pregnancy, and an empty uterus with an adnexal mass and/or the presence of free fluid together with a positive urine test gives a very high probability of an ectopic pregnancy. The absolute diagnosis of an ectopic pregnancy by the demonstration of a living fetus outside the uterus is an uncommon finding (8%). Conversely, an empty uterus alone on ultrasound examination in the absence of other ultrasound findings in those patients with a positive serum test is not a reliable guide to the presence of an ectopic pregnancy unless there is an irrefutable conception date at least 5 weeks previously. It is recommended that pathology laboratories and ultrasound departments establish absolute levels of HCG above which an intrauterine pregnancy should always be visible within the uterus. Given appropriate attention to the clinical condition of the patient, the combined use of diagnostic ultrasound, simple urine pregnancy tests and serum assays of beta HCG levels goes a long way to discriminating between those patients with and those without an ectopic pregnancy.     

The 'simple' ovarian cyst: aspirate or operate?

One hundred ultrasound-guided ovarian cyst punctures were performed in 88 patients. To minimize the risk of unexpected malignancy, only persistent or painful cysts less than 10 cm in diameter were aspirated, cysts with solid areas or multiple locules were excluded. Cytological diagnosis was not possible in 72 of the 100 fluids; of the others 20 contained cells suggestive of follicular or luteal cysts, four samples suggested endometriosis and four benign tumours of epithelial origin. Oestradiol levels were high in 54 cystic fluids, and a combination of oestradiol estimation and cytology facilitated the identification of a follicular origin. Most such patients would normally have undergone surgery, but this was eventually required in only 10 of 60 in whom the cyst fluid was clear or slightly blood-stained and in 16 of the 28 with heavily blood-stained fluid. Ultrasound-guided ovarian cyst puncture would appear to be a valid alternative to surgery for carefully selected benign ovarian cysts especially when the cyst is considered not to contain blood.     

Monitoring Early Pregnancy with Transvaginal Ultrasound and Choriogonadotrophin Levels

Serum human chorionic gonadotrophin levels were correlated with gestational sac size detected by transvaginal ultrasound in a series of 178 women undergoing in vitro fertilization. The improved resolution of transvaginal ultrasound enables pregnancy to be detected between 17 and 20 days post-ovum retrieval, when HCG levels were greater than an average threshold level of 1,300 IU/L. The lower HCG discriminatory zone enables improved evaluation of ectopic pregnancies. Also, higher HCG titres observed in multiple pregnancies enable estimation of implantation rates when more than one embryo is transferred.     

Longitudinal magnetic resonance imaging study of perfusion and diffusion in stroke: evolution of lesion volume and correlation with clinical outcome.

A prospective longitudinal diffusion-weighted and perfusion-weighted magnetic resonance imaging (DWI/PWI) study of stroke patients (n = 21) at five distinct time points was performed to evaluate lesion evolution and to assess whether DWI and PWI can accurately and objectively demonstrate the degree of ischemia-induced deficits within hours after stroke onset. Patients were scanned first within 7 hours of symptom onset and then subsequently at 3 to 6 hours, 24 to 36 hours, 5 to 7 days, and 30 days after the initial scan. Lesion evolution was dynamic during the first month after stroke. Most patients (18 of 19, 95%) showed increased lesion volume over the first week and then decreased at 1 month relative to 1 week (12 of 14, 86%). Overall, lesion growth appeared to depend on the degree of mismatch between diffusion and perfusion at the initial scan. Abnormal volumes on the acute DWI and PWI (<7 hours) correlated well with initial National Institutes of Health (NIH) stroke scale scores, outcome NIH stroke scale scores, and final lesion volume. DWI and PWI can provide an early measure of metabolic and hemodynamic insufficiency, and thus can improve our understanding of the evolution and outcome after acute ischemic stroke.     

Rapid monitoring of diffusion, DC potential, and blood oxygenation changes during global ischemia. Effects of hypoglycemia, hyperglycemia, and TTX.

BACKGROUND AND PURPOSE: The increasing interest in diffusion-weighted MRI (MRI) for diagnosis and monitoring of acute stroke in humans calls for a sound understanding of the underlying mechanisms of this image contrast in acute cerebral ischemia. The present study aimed to show that a rapid decrease in brain-water apparent diffusion coefficient (ADC) occurs coincident with anoxic depolarization and that this change is delayed by hyperglycemia and sodium channel blockade but accelerated by hypoglycemia. METHODS: Rats were divided into groups: normoglycemic, hypoglycemic, and hyperglycemic, and those given local tetrodotoxin (TTX) application. Cardiac arrest was effected by intravenous KCl injection during serial high-speed diffusion and blood oxygenation-sensitive gradient-recalled echo MRI. Brain DC potential was recorded simultaneously. Serial ADC maps were calculated from the diffusion-weighted data and fitted to a model function to measure the delay between cardiac arrest and rapid ADC decrease. RESULTS: The time of anoxic depolarization indicated by DC change agreed well with the rapid drop in ADC in all groups; both were accelerated with hypoglycemia and delayed by hyperglycemia. A more gradual ADC decline occurred before anoxic depolarization, which was more pronounced in hyperglycemic animals and less pronounced in hypoglycemic animals. Rapid drop in ADC was also delayed by local TTX application. Changes in gradient-recalled echo image intensity were not significantly different among groups. CONCLUSIONS: While much of the ADC decrease in ischemia occurs during anoxic depolarization, significant but gradual ADC changes occur earlier that may not be due to a massive loss in ion homeostasis.     

High speed diffusion magnetic resonance imaging of ischemia and spontaneous periinfarct spreading depression after thromboembolic stroke in the rat.

Spontaneous episodes of transient cell membrane depolarization (spreading depression [SD]) occur in the surroundings of experimental stroke lesions and are believed to contribute to infarct growth. Diffusion-weighted imaging (DWI) is capable of detecting the water shifts from extracellular to intracellular space associated with SD waves and ischemia, and can make in vivo measurements of these two features on a pixel-by-pixel basis with good temporal resolution. Using continuous high speed DWI with a temporal resolution of 12 seconds over a period of 3 hours, the in vivo contribution of spontaneous SDs to the development of ischemic tissue injury was examined in 8 rats using a thromboembolic stroke model. During the observation period, the initial lesion volume increased in 4 animals, remained unchanged in 1 animal, and decreased in 3 animals (most likely because of spontaneous clot lysis). Irrespective of the lesion evolution patterns, animals demonstrated 6.5 +/- 2.1 spontaneous SDs outside of the ischemic core. A time-to-peak analysis of apparent diffusion coefficient (ADC) changes for each SD wave demonstrated multidirectional propagation patterns from variable initiation sites. Maps of the time constants of ADC recovery, reflecting the local energy supply and cerebral blood flow, revealed prolonged recovery times in areas close to the ischemic core. However, repetitive SD episodes in the periinfarct tissue did not eventually lead to permanent ADC reductions. These results suggest that spontaneous SD waves do not necessarily contribute to the expansion of the ischemic lesion volume in this model.     

Mortality and two year outcome of infants of birthweight 500-1500 g: relationship with neonatal cerebral ultrasound data

Cranial ultrasounds were performed on 218 (96%) of 227 liveborn infants of birthweight 500-1500 g delivered in the Royal Women's Hospital, Melbourne, Australia, in an 18-month period concluding in March 1982. Seventy-two (31.7%) of the children died; 28 children (38.9%) had cerebroventricular haemorrhage, 35 (48.6%) showed no bleeding and there were nine (12.5%) with no data. Paired necropsy and ultrasound data were congruent in 22 (88%) of 25 children. One hundred and forty-eight (95.5%) of 155 survivors were seen at 2 years of age. Forty-one (28%) had cerebroventricular haemorrhage; nine children (6%) had both ventricular dilatation and haemorrhage and two had ventricular dilatation alone. Apart from a marginal advance in gestation and higher number of immigrant and less educated mothers in children without cerebroventricular haemorrhage, all other perinatal, biographical and social variables between those with haemorrhage and those without were similar. The major handicap rate overall was 14.2% (21 patients). The children with cerebroventricular haemorrhage had a trend for greater prevalence of handicap and lower mean Bayley psychological scores. This was even more evident with ventricular dilatation being present. Of children with major handicap 57.1% (12/21) had normal serial ultrasound findings during their primary hospitalization. Major handicap occurred in 15% (3/20) of children with grade 1 haemorrhage, 23.5% (4/17) with grade 2 or 3 bleeds and 25% (1/4) of those with grade 4 haemorrhage. Laterality of cerebral palsy did not correlate with ultrasound findings. Ultrasound findings did not improve statistical prediction of deaths or major handicap.