A simplified ingestion procedure for esophageal capsule endoscopy: initial evaluation in healthy volunteers.

BACKGROUND AND STUDY AIMS: Initial studies on esophageal capsule endoscopy (PillCam ESO) reported excellent sensitivity and specificity, but these were followed by mixed results in several subsequent studies, probably due to deviations from the recommended ingestion protocol and the inconvenience of capsule ingestion in the supine position. The aim of this study was therefore to test a simplified ingestion procedure (SIP) for PillCam ESO. PATIENTS AND METHODS: Using a cross-over study design, the SIP was prospectively compared with the original ingestion procedure for PillCam ESO in 24 healthy volunteers (15 men, nine women; mean age 44, range 27 - 70) and evaluated for: bubbles/saliva interference at the Z-line, Z-line circumferential visualization (quadrants), and convenience and ease of the ingestion procedure. All Rapid 4 videos were reviewed in a randomized manner and read by an experienced PillCam ESO reader blinded to the ingestion procedure used. RESULTS: It was found that the SIP significantly improved visualization in comparison with the original ingestion procedure, with less interference due to bubbles/saliva observed at the gastroesophageal junction ( P = 0.002) and improved visualization of the Z-line ( P = 0.025). Although the esophageal transit time was significantly faster with the SIP (3 : 45 min vs. 0 : 38 min; P = 0.0001), there were no differences in the number of Z-line frames/images captured. CONCLUSIONS: This new, simplified ingestion procedure for PillCam ESO provides significantly improved visualization of the Z-line in healthy volunteers. The overall test characteristics of PillCam ESO using SIP should be tested in patients with esophageal disease.

Measurement of cardiac function in conscious rats.

The goal of this study was to establish that 1. blood velocity profile in the rat aorta is parabolic, and 2. measure of left ventricular thickening fraction can be used in rats. Spontaneously hypertensive and normotensive Wistar Kyoto rats were instrumented with a 20-MHz pulsed Doppler flow probe around the thoracic aorta and a 20-MHz pulsed Doppler thickening probe on the left ventricle. Doppler frequency shifts were measured throughout the entire aorta diameter, and individual blood velocity profiles were constructed. It was demonstrated that blood velocity in the ascending aorta of rats is laminar; therefore, cardiac output can be measured using the pulsed Doppler method. In Wistar Kyoto rats, left ventricular thickening fraction was 24 +/- 1% and 25 +/- 1%, 2 and 3 weeks following surgery. In spontaneously hypertensive rats, left ventricular thickening fraction was 22 +/- 2%. Halothane depressed left ventricular thickening fraction, whereas isoproterenol increased left ventricular thickening fraction in conscious rats. Thus, pulsed Doppler technique is a valuable tool for evaluating cardiovascular function in conscious rats.

Endometrial laser intrauterine thermotherapy: the first series of 100 patients observed for 1 year.

OBJECTIVE: To describe a new instrument (GyneLase) that offers a new approach (endometrial laser intrauterine thermal therapy [ELITT]) to treatment of menorrhagia and to evaluate the efficacy of ELITT in the management of dysfunctional uterine bleeding. DESIGN: Prospective study. SETTING: University hospital. PATIENT(S): 100 premenopausal women with dysfunctional uterine bleeding were observed for 1 year. INTERVENTION(S): Intrauterine laser thermotherapy with a diode laser. MAIN OUTCOME MEASUREMENT(S): Amenorrhea rate after 1 year. RESULT(S): The amenorrhea rate after 1 year of follow-up was 71%, and the rate of amenorrhea/severe hypomenorrhea rate was >90%; these rates are much higher than those in the literature after such procedures as electrosurgery or intrauterine thermal balloon therapy. The ELITT procedure is an inherently safe and simple alternative, providing controlled and effective treatment of the entire endometrium. In contrast to traditional endometrial ablation using a neodymium yttrium-aluminum-garnet laser, the ELITT procedure does not require intensive training or hysteroscopic control; it is also far less risky, because the power used per unit area is 1,000 times lower. CONCLUSION(S): The ELITT procedure is a new nonhysteroscopic technique for endometrial ablation. The technique is very safe and offers the highest amenorrhea rate to date in the literature.

Endometrial laser intrauterine thermo-therapy (ELITT): a revolutionary new approach to the elimination of menorrhagia.

Various non-hysteroscopic procedures have been developed in the attempt to treat dysfunctional uterine bleeding that fails to respond to medical treatment efficiently and easily. Among these procedures is low-dose laser radiation of the endometrium with the diode source, which is characterized by the highest incidence of amenorrhea.

Parental attitudes toward obstetric ultrasound examination.

OBJECTIVE: The aim of the study was to assess the effect of ultrasound examination on parental attitudes and anxieties. MATERIAL AND METHOD: Ultrasound examinations were carried out on 1,089 pregnant women with uncomplicated pregnancies at a mean gestational age of 20.9 weeks (minimum 10 weeks). Before and after the ultrasound examination, patients completed a questionnaire comprising 26 five-point numerical scales relating to anxiety levels, and difference scores for pre- and post-scan levels of fears and anxieties were computed. RESULTS: We showed that the reduction of anxiety following ultrasound examination was inversely related to gestational age, but was unrelated to demographic or medical variables, such as the risk level at the time of the scan. Similarly, anxiety was not reduced because of the presence of the spouse, although the spouse's presence did significantly increase inter-partner bonding. CONCLUSION: This study showed that "routine" ultrasound scan may have significant psychological effects on parental attitudes toward each other and the fetus.

Ultrasonographic "endometrial three-layer" pattern: a unique finding in ectopic pregnancy.

Although diagnostic ultrasonography is playing an increasing role in the investigation of the patient with suspected ectopic pregnancy (EP), it has significant limitations in the very early stages of pregnancy. By sonographically exploring the intrauterine echoes in 45 cases of documented EP, we demonstrated a unique pattern in 28 cases (62.2%). A well-defined spheric structure forming an endometrial three-layer (ETL) pattern was seen, probably formed by a midline echo between the two adjacent edematous proliferative layers of the endometrium, the latter resembling the late proliferative endometrium. In 17 patients with a proved EP (37.8%), the ETL pattern was not demonstrated. However, the ETL was not demonstrated in all 40 cases of early intrauterine pregnancy and all 50 cases of miscarriage. These findings suggest a 100% specificity and a sensitivity of 62.2% for the ETL pattern in the diagnosis of EP.

Clinical relevance of myocardial "stunning".

Experimental studies have demonstrated that myocardium reperfused after reversible ischemia exhibits prolonged depression of contractile function ("stunning"). Despite the multiplicity of clinical situations in which myocardial stunning would be expected to occur, investigation of this phenomenon in humans has been hindered by several major problems, including the limited accuracy of the methods available to measure regional left ventricular function, the inability to quantify regional myocardial blood flow during acute ischemia, the difficulty in establishing with certainty, the beginning and end of an ischemic episode, and the uncontrolled influence of variables (such as preload, afterload, adrenergic tone, and inotropic therapy) that have a major impact on postischemic dysfunction. The main problem is to discern whether a reversible defect of contractility is caused by stunning, silent ischemia, or hibernation (i.e., chronic ischemia). This differential diagnosis requires the simultaneous measurement of regional myocardial function and flow, which thus far has not been generally possible. Despite these limitations, however, numerous clinical observations suggest that stunning does occur in various settings in which the myocardium is exposed to transient ischemia, including coronary angioplasty, exercise-induced angina, angina at rest (unstable or variant), acute myocardial infarction with early reperfusion, open-heart surgery, and cardiac transplantation. Recognition of this entity is important, amongst other reasons, because it is likely to cause significant morbidity and because it is potentially correctable with inotropic therapy or even preventable with antioxidant therapy. In addition, the appreciation of the phenomenon of myocardial stunning should allow the clinician to assess the efficacy of reperfusion therapy with greater accuracy and to recognize that patients should not be denied mechanical revascularization solely because of an abnormal left ventricular wall motion. Perhaps the most intriguing clinical implication of the concept of myocardial stunning is the possibility that in patients who exhibit frequent episodes of ischemia in the same territory, the myocardium may not be able to fully recover between episodes and thus may remain reversibly depressed for prolonged periods of time, or even chronically, which could account for some cases of "ischemic cardiomyopathy." Our understanding of myocardial stunning in humans is still relatively crude and will not significantly improve until studies are performed that measure simultaneously regional myocardial perfusion and function (so that stunning can be differentiated from silent ischemia and hibernation). Future important areas of research should also include the elucidation of whether stunning can become chronic and the evaluation of therapies (such as antioxidant treatments) designed to prevent this contractile abnormality.(ABSTRACT TRUNCATED AT 400 WORDS)

An ultrasonic method for measuring tissue displacement: technical details and validation for measuring myocardial thickening.

We have developed a method for measuring myocardial thickening from a single ultrasonic transducer attached to the epicardium. Displacement of the underlying myocardial tissue is measured by following the phase of the echoes within a sample volume range-gated across the myocardium. The output is in the form of an analog signal. To verify the accuracy, resolution, and limitations of the system, we derived the equations relating the position of a reflector to the phase of its echo and compared the system output in vitro to a known input using a single moving target and a random distribution of scatterers, and in vivo to that of an ultrasonic transit-time dimension gauge. The results demonstrate that the 10 MHz system can accurately follow the motion of single or multiple targets with a resolution of 0.02 mm. In 25 dogs myocardial thickening measured with the displacement system compared favorably in both waveform and magnitude with thickening measured by the two-crystal transit-time method. Applications for the displacement method include: quantification of regional ventricular function in animal models of cardiovascular diseases, measurement of endocardial to epicardial differences in the deformation of regional myocardium during the cardiac cycle, and evaluation of regional cardiac function in patients during and after corrective cardiac surgery.

Implantable sensor for intraoperative and postoperative monitoring of blood flow: a preliminary report.

We have developed an implantable 20 MHz Doppler flow sensor, to monitor blood flow in patients after operation. During surgery the sensor is wrapped around a blood vessel and secured in place with a releasable tie. No tissue puncturing techniques are required. The lead wires, together with a release cable, are exteriorized through the chest wall. Several days after operation, the tie is externally released, and the sensor is pulled out. Twenty-seven sensors were implanted in 24 dogs for up to 16 days. All were extracted successfully with minimal visible behavioral reaction in the awake dogs and caused no thrombosis or vascular damage. The Doppler velocity signals had excellent linear correlations (r = 0.99) with data from electromagnetic flow sensors and timed blood collections. In addition, the sensors were applied to coronary artery bypass grafts in 31 patients for up to 2 days after operation. High-quality signals were obtained, and intraoperatively recorded signals agreed well with simultaneous electromagnetic flow tracings. All sensors were extracted with minimal discomfort to the awake patients and with no complications. Thus, the implantable flow sensor is a safe, reliable, accurate, and simple method for intraoperative and postoperative monitoring of blood flow in vessels 2.5 to 5 mm in diameter.

An accurate, nontraumatic ultrasonic method to monitor myocardial wall thickening in patients undergoing cardiac surgery.

Measurement of systolic wall thickening by sonomicrometry provides an accurate index of regional left ventricular function, but the trauma of crystal insertion limits its widespread clinical use. The first clinical application of a 10 MHz ultrasonic Doppler probe that can be either sutured or applied by suction to the epicardium and can measure wall thickening at any depth of the left ventricular wall is described. In 18 dogs, measurements obtained with the suction probe correlated well (r = 0.97) with those of a previously validated sutured probe. To assess clinical feasibility, the probe was applied to the epicardium of patients undergoing coronary bypass surgery. Good quality wall thickening signals were obtained with no complications. Transmural left ventricular thickening fraction before bypass surgery was 34 +/- 3% (mean value +/- SE) at the mid-ventricular lateral wall, 33 +/- 4% at the anterior basal wall and 26 +/- 4% at the mid-ventricular posterior wall. Right ventricular thickening fraction averaged 25 +/- 3%. Endocardial thickening fraction tended to exceed epicardial thickening fraction, although the difference attained statistical significance (p less than 0.05) only at the anterior basal wall. On average, thickening fraction during the immediate postoperative period remained unchanged compared with the preoperative values, but a marked individual variability was observed, with 7 of 15 patients exhibiting a decrease and 8 an increase. Exteriorization of the wires attached to the sutured probe allowed continuous in situ monitoring of wall thickening in the postoperative period and subsequent removal of the probe. In six patients the crystal was left in place for 48 to 72 h after surgery and then removed without complications; good wall thickening signals were obtained for the entire period during which the probe was implanted. Thus, the Doppler probe is an accurate, atraumatic method for measuring right and left ventricular regional function. Transmural, endocardial and epicardial function can be mapped at various sites during surgery, and post-operatively one can monitor serial changes of regional function and assess the effects of cardioplegia and other therapeutic interventions. This technique should be useful for both investigative and clinical purposes.

An experimental study of pressure losses in pulsatile flows through rigid and pulsating stenosis.

The time-dependent pressure curves of a pulsatile flow across rigid and pulsating stenoses were investigated experimentally in a laboratory simulator of the outflow tract of the heart right ventricle. The experiments were performed within the range of physiological conditions of frequency and flow rate. The experimental setup consisted of a closed flow system which was operated by a pulsatile pump, and a test chamber which enabled checking different modes of stenosis. Rigid constrictions were simulated by means of axisymmetric blunt-ended annular plugs with moderate-to-severe area reductions. The pulsating stenosis consisted of a short starling resistor device operated by a pulsating external pressure which was synchronized by the pulsatile flow. It was found that the shape of the time-dependent pressure curve upstream of the stenosis was different in the case of rigid stenosis than in the pulsating one. Potential clinical applications of the work may relate to diagnosis of the type of stenosis in the congenital heart disease known as Tetralogy of Fallot.