[Contrast media-enhanced duplex ultrasonography of liver tumors]

The differentiation of focal liver processes is a daily clinical problem. A new option in addition to magnetic resonance tomography has been created with the development of new stable sonographic contrast agents. In this paper, Levovist was studied as a sonographic contrast agent in the detection of specific tumour perfusion patterns. All focal liver processes were proven by cytology or histology. In 19 of 22 cases there was a pathological diagnosis. In 5 of 7 haemangiomas a feeding vessel was visualised. In 3 focal nodular hyperplasias intense intratumoural enhancement was visible shortly after injection. In 2 cases of hepatocellular carcinomas tumoural neovascularisations were visualised which were not seen before the injection of Levovist. The new sonographic contrast agents provide better differentiation of specific perfusion patterns of liver tumours than normal duplex sonography.

[Non-invasive monitoring of intracranial pressure changes through the ear]

Otoacoustic emissions are low energy vibrations generated by the inner ear during the physiologic process of hearing. The authors measured transiently evoked otoacoustic emissions in normal hearing individuals placed in Trendelenburg position and during diagnostic elevation of intracranial pressure in neurosurgical patients. In Trendelenburg position and at elevated intracranial pressure and reproducible phase shift of otoacoustic emissions could be observed. This phase shift was linear to the pressure increase of intracranial liquids. According to the hypothesis of the authors intracranial pressure increase is transmitted to the inner ear (possibly by the cochlear aqueduct) and thereby the mechanical load on the stapes footplate is elevated. This, in turn, causes a stiffening of the annular ligament which changes the angle of the impedance vector and thereby the phase of the whole vibrating system. By measuring the phase of otoacoustic emissions it is possible to monitor intracranial pressure in various clinical states.

Intrasound vibration testing in acute ankle injuries

OBJECTIVES

To determine the accuracy of intrasound vibration testing (IVT) in comparison with plain radiography in the diagnosis of acute ankle fractures.

METHODS

A group-sequential, nonrandomized, double-blind, observational study design was used. A convenience sample of patients were studied, aged > or = 10 years, with acute ankle injuries, undergoing ankle radiography, evaluated at a community teaching hospital ED. Excluded were cases involving injuries of > 24 hours' duration, inadequate documentation, protocol violation, or positive IVT on the uninjured ankle. IVT was performed with the intrasound apparatus placed on the anterior and posterior aspects of the medial and lateral malleoli of the uninjured and injured ankles; positive IVT was defined as patient withdrawal secondary to pain.

RESULTS

Of 105 patients enrolled, 8 were excluded; 1 for inadequate documentation, 5 for protocol violation, and 2 for positive IVT of the uninjured ankle. Of the 97 patients analyzed, 13 had fractures identified by radiography, including 9 lateral malleolar, 1 medial malleolar, 1 bimalleolar, and 2 talar fractures. Only 5 of the 13 fractures were detected with IVT (sensitivity = 39%; 95% CI: 14-68%). Seventy of 84 nonfractured ankles had negative IVT (specificity = 83%; 95% CI: 74-91%). Of the 19 with positive IVT, 5 had fractures (positive predictive value of 26%; 95% CI: 9-51%). Of the 78 with negative IVT, 70 had no fracture (negative predictive value of 90%; 95% CI: 81-96%). Overall, 75 of 97 IVTs were correct (77%), most of which were among patients without fractures.

[Diagnosis of osteoporosis with ultrasound densitometry of the calcaneus]

PURPOSE

We evaluated the speed of sound (SOS) and broadband ultrasound attenuation (BUA) at the os calcis as an indicator of osteoporosis and observed the age-related changes in ultrasound values in normal women.

MATERIALS AND METHODS

BUA and SOS were measured in 236 women using the "Achilles" densitometer (Lunar, Madison, Ohio). From the BUA and SOS values the BUA/SOS Index ("Stiffness" Index) is calculated. We investigated 55 female patients with osteoporosis (aged 43-85 years) and 181 healthy women (aged 20-80 years).

RESULTS

Ultrasound values for women with osteoporosis were significantly lower than those for the normal control group. The Z-score compared with young normals was higher for the BUA/SOS Index (-3.1) than for BUA (-2.5) and SOS (-3.0). At a BUA/SOS Index of 68 the sensitivity was 85 %, and the specificity was 77 % for patients with osteoporotic fractures. We found a significant decline with age in SOS (r = -0.55), BUA (r = -0.50) and BUA/SOS Index (r = -0.57).

CONCLUSION

Ultrasound bone densitometry at the os calcis can be used as a screening test in the diagnosis of osteoporosis.

Development of a new Er: YAG laser conception for laser sclerostomy ab externo: experimental and first clinical results

The erbium:YAG laser is a preferable energy source for laser sclerostomy ab externo due to the high absorption of its radiation (2940-nm wavelength) in the aqueous parts of scleral tissue. It has thus far been a disadvantage that laser energy has to be transmitted from the laser source to the application site via very susceptible special optical fibers (ZrF). As a consequence of technical improvements, the laser source could be integrated into the application probe. Therefore, only a robust quartz fiber was necessary for contact application. A fiber diameter of 400 microns was chosen according to the experience gained in previous studies. A total of 24 eyes with chronical open-angle glaucoma were treated. A fistula end-point detection unit was developed for safe indication of a full-thickness perforation of the sclera. With a fiber diameter of 400 microns, a postoperative success rate of about 54% was achieved at 6 months follow-up. The automated full-thickness perforation detection prevented the application of additional, surplus laser pulses in the anterior chamber. The postoperative success rate could be improved over that achieved in previous studies. The new device/conception offers more technical reliability and is a further step toward minimally invasive fistulating laser surgery of open-angle glaucoma.

[Rapid determination of the value-determining components in sausage products by near-infrared transmission spectroscopy]

A rapid method for the simultaneous determination of water, fat, crude protein, connective-tissue-protein and connective-tissue-protein free meat protein in sausage products with the help of near-infrared transmission spectroscopy (NIT) is presented. The calibrations for the each constituent were achieved with the chemometric method "partial least squares" (PLS) and validated with the added samples. Correlation coefficients between the reference methods and NIT were > or = 0.95 for water, fat, crude protein and connective-tissue-protein frei meat protein, and > or = 0.86 for connective-tissue-protein. The precision of NIT was comparable with the reference methods.

Neuropsychological and neuroanatomical correlates of confabulation

In the present exploratory investigation we report nine confabulatory patients of comparable age, education, and general level of intelligence in the acute epoch of recovery after rupture and clipping of ACoA aneurysms. Five of the nine cases had "spontaneous" confabulation, severe anterograde amnesia, markedly poor attentional and executive functions, and denial of illness. These patients all had multiple lesions that involved basal forebrain, ventral frontal lobe, and striatum. The other four patients manifested only "momentary" or "provoked" confabulations. These patients also had severe anterograde amnesia but showed relatively mild deficits in executive functions. These patients had lesions restricted to the basal forebrain except for one who had additional orbital frontal damage. Analysis of these two groups of confabulatory patients suggests that there is a common profile of deficits and anatomic foundation associated with confabulation; "spontaneous" confabulation appears to require extensive, simultaneous disruption of medial basal forebrain and frontal cognitive systems resulting in profound executive and memory deficits, whereas more limited lesions to the basal forebrain or orbital frontal cortex will result in "transient" or "provoked" confabulatory responses and a more restricted profile of cognitive deficits.

Cochlear microphonics recorded from fetal and newborn sheep

PURPOSE

Sounds present within the uterus stimulate the fetal inner ear and central auditory pathway. This study was undertaken to determine the efficiency of transmission of exogenous airborne stimuli to the fetal inner ear. In this way, we may quantify the extent to which the fetal auditory system is isolated from sounds produced outside the mother.

MATERIALS AND METHODS

Cochlear microphonics were recorded from fetal and newborn sheep to evaluate the extent to which the fetus is isolated from sounds exogenous to the ewe. Electrodes were surgically placed in contact with the round window membrane in nine near-term fetal sheep. Cochlear microphonics were recorded in response to 1/3 octave-band noises (0.125 to 2.0 kHz) delivered through a loudspeaker 1.8 m from one side of the pregnant ewe. Sound pressure levels generated by the noises were simultaneously recorded ex utero with a microphone and in utero with a hydrophone previously sutured to the fetal neck. After cochlear microphonic amplitudes were recorded, the fetus was delivered through an abdominal incision. Recordings were repeated from the newborn lamb. Fetal sound isolation was calculated as the difference between the sound pressure levels that were necessary to evoke equal cochlear microphonic amplitudes from the fetus and from the newborn lamb.

RESULTS

The sound attenuation observed was variable for all frequencies. The fetus was isolated from external sounds by 11.1 dB for 0.125 kHz, 19.8 dB for 0.25 kHz, 35.3 dB for 0.5 kHz, 38.2 dB for 1.0 kHz, and 45.0 dB for 2.0 kHz.

CONCLUSIONS

Other investigators have demonstrated that the immature auditory system is more susceptible to damage produced by noise exposure than is the mature auditory system. Low-frequency noise produces damaged cells that later in life code higher frequencies. A possibility of fetal hearing loss produced by intense noise exposure needs more careful evaluation.

[Use of ultrasound in the surgical emergency unit]

The sonography is very important diagnostic method for the abdominal emergency cases. This diagnostic screening method should be available in the surgical emergency station. Liquid, abscesses, organ ruptures and also many inflammations can be diagnosed with this not invasive method. It is our opinion that a training program in sonography should be available for young surgeons for the judgement of the abdominal emergency cases.

[Consequences of interventional sonography for abdominal surgery]

The sonographic-radiologically guided puncture and catheter insertion enables certain palliative and curative therapeutic procedures to be performed. Liver abscesses represent the most common examples for this procedure, although interabdominal abscesses as well as pancreatic pseudocysts can also be treated successfully. In our collection of clinical cases various preformed pigtail catheters were employed using either the Seldinger-principle or, with help of a rigid needle, introduced directly into the lesion. Advantages of sonographically guided therapeutic interventions include quick implementation without radiation exposure, immediate recognition of possible complications as well as negligible expenditures. Ultrasonically guided therapeutic interventions should be undertaken only through the close collaboration between intervening radiologists and abdominal surgeons. Only so are they both low-risk and successful.

[Percutaneous pancreatic pseudocyst drainage: a combined sonographic-endoscopic procedure]

Certain pancreas-pseudocysts can be effectively drained either transgastrically or transduodenally using endoscopic procedures. Applicable methods include repeated fine needle punctures, insertion of a drainage tube or the percutaneous pseudocyst-drainage according to Hancke. The percutaneous sonographic pancreas-pseudocyst drainage represents an alternative or an adjunct to the classical surgical cyst drainage employing a cysto-jejunostomy or cysto-gastrostomy. The indications are analog to the surgical cysto-enterostomy, whereas the optimal method for each individual patient should be decided by interdisciplinary consultation. The following report presents 21 case studies of pancreas-pseudocysts which were treated conservatively using ultrasonographical procedures.

Transcatheter bronchial artery embolization in the multimodality management of massive hemoptysis

To illustrate the potential role of transcatheter bronchial artery embolization (TBAE) in the multimodality management of massive hemoptysis, we describe a case in which TBAE was successfully employed as the definitive therapy. In recent years, the technique of TBAE has joined the armamentarium of managing methods for massive hemoptysis. While massive hemoptysis has traditionally been defined in terms of the volume of blood produced within a period of time, with a rate of 600 ml in 24 hours the most commonly used definition, a more functional definition has been proposed: bleeding into the tracheobronchial tree at a rate that poses a threat to life. It is the life-threatening nature of this symptom that often results in the early involvement of thoracic surgeons in the care of these patients.

Physical exercise conditioning in the absence of weight loss reduces fasting and postprandial triglyceride-rich lipoprotein levels

The effect of physical exercise conditioning on fasting and postprandial lipoprotein levels was studied in six normolipidemic subjects. The study consisted of two phases: a baseline stabilization phase in which subjects maintained their regular physical activity and an exercise conditioning phase in which subjects had 29 exercise sessions during a 7-week period. Each of these sessions consisted of jogging on a treadmill for 30 minutes. The subjects averaged 15.2 miles/wk. To control for possible confounding factors, such as changes in diet composition and weight loss, we placed the subjects on a metabolic diet and increased their daily caloric intake during the exercise phase. At the end of each phase of the study, a vitamin A-fat loading test was done to specifically label and follow postprandial lipoprotein levels, and a maximum oxygen consumption test was done to evaluate the subjects' physical fitness. The exercise conditioning phase significantly increased the subjects' aerobic capacity and postheparin lipoprotein lipase activity, and the phase decreased fasting triglyceride levels. Physical exercise also significantly decreased chylomicron (Sf greater than 1,000) levels by 37%. In summary, this study suggests that physical exercise conditioning reduces fasting and postprandial lipoprotein levels by increasing the catabolism of triglyceride-rich particles. Because these particles may have a role in atherogenesis, this could be a major mechanism by which exercise prevents coronary heart disease.

[Ultrasonic study of the breast: examination technic--criteria for diagnosis]

Sonography of the breast is an important supplement of conventional mammography and allows for differentiation between solid and cystic lesions. Moreover, fine needle puncture under ultrasound guidance and permanent view is possible. Typical sonographical signs of benign and malignant focal lesions are demonstrated comparing them with corresponding mammograms. Ultrasound examination alone, however, is insufficient for screening of breast cancers.

Quantitative determination of verapamil and metabolites in human serum by high-performance liquid chromatography and its application to biopharmaceutic investigations

A specific and sensitive high-performance liquid chromatographic method for the quantitative analysis of verapamil and N-desmethylverapamil in human serum is described. The analytes were extracted from serum using diethylether under alkaline conditions, followed by back extraction into dilute hydrochlorid acid for chromatographic analysis on a reversed-phase column with a mobile phase consisting of acetonitrile, water and perchloric acid at a flow rate of 1 l/min. The analytes were detected by fluorescence detection, the influence of temperature on retention is discussed. The method is linear, quantitative and reproducible for two calibration ranges in serum (2.5 ng/ml-100 ng/ml and 12.5 ng/ml-500 ng/ml) using peak area ratios analyte/internal standard for quantification. At ultimate sensitivity, concentrations down to 250 pg/ml could be assayed. The method was selective to 6 other metabolites of verapamil and common exogenous interferences. It was applicated to the serum samples of a comparative 120 mg - verapamil hydrochloride tablet single dose two-way cross-over study comprising 18 volunteers. The pharmacokinetic data for both formulations are presented.