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.

Evolution and regression of pancreatic calcification in chronic pancreatitis. A prospective long-term study of 107 patients

Pancreatic calcifications are virtually pathognomonic of chronic pancreatitis and develop in up to 90% of patients with alcoholic chronic pancreatitis in series with long-term results. We investigated the natural course of pancreatic calcification in a prospective longitudinal study over the past 23 yr. All patients were studied at regular intervals with particular regard to etiology, clinical findings, surgery, pancreatic function, and pancreatic calcification visible by x-ray (e.g., film series in three projections centered on the pancreas). We evaluated the findings of 107 patients with x-ray documentation of pancreatic calcification in at least three film series over a period of 4 yr or longer. Eighty-four patients had alcoholic chronic pancreatitis (group A) and 23 patients had nonalcoholic chronic pancreatitis (group B). Four hundred seventy-two film series of group A and one hundred forty-two film series of group B were reviewed independently by two expert teams. Both series were graded according to a score system in terms of intensity and distribution of pancreatic calcification (correlation of grading r = 0.91). The duration of calcification averaged 10 yr in group A and 12.6 yr in group B. Similar dynamic changes of pancreatic calcification were noted in groups A and B. Chronologically, three phases of evolution could be distinguished. After an initial increase (phase 1), greater than 50% of cases reached a plateau of stationary calcification (phase 2). Approximately one-third of cases showed a marked decrease of calcification in late phases of chronic pancreatitis (phase 3). Dissolution of pancreatic stones was related primarily to duration of chronic pancreatitis (duration of calcification and marked pancreatic dysfunction), and occurred frequently (but not exclusively) in patients after ductal drainage procedures. These results indicate that spontaneous dissolution of pancreatic stones is a rather common biologic phenomenon. The factors responsible for dissolution of stones remain to be elucidated.

MR and CT findings in infected ventricular aneurysm repair

The magnetic resonance findings in a case of infection at a ventricular aneurysm repair site 7 years following surgery are presented.

[An incidental finding of renal cysts: routine occurrence or a finding deserving clarification?]

Since the introduction of new non-invasive diagnostic techniques such as abdominal ultrasound and computerized tomography, simple renal cysts are diagnosed with increasing frequency. Over 30% of patients over 50 years of age are found to have simple renal cysts of different size. A cystic renal mass may represent a simple renal cyst without clinical relevance, a cystic renal carcinoma, early evidence of polycystic kidney disease in a young patient, a rare cause of renal hypertension, a source of infection in a symptomatic patient (infected renal cyst), or a manifestation of an infectious disease (renal abscess, echinococcus cyst). The differential diagnosis and management of a cystic renal mass therefore remain a clinical problem. In the past, surgical exploration of a cystic renal mass was frequently performed. Today, modern diagnostic techniques such as ultrasound-guided percutaneous cyst puncture with cytological analysis of the cyst content, or computerized tomography, are considered the methods of choice. They are particularly useful in case of doubt about the dignity of a cystic renal mass. The determination of renal venous renin levels may be useful in differentiating the causal role of a renal cyst in a patient with hypertension. The management of a cystic renal mass depends on the underlying disease.