[Leiomyosarcoma of the pulmonary artery]. / Leiomyosarkom der Pulmonalarterie.

In a 58-year-old man, a leiomyosarcoma was found to be the cause of unclear thoracal pain on the right side. The initial diagnose was an embolus of the pulmonary artery. The MRI showed a suspicious area similar to an intravasal tumor.

[Ultrasound examination of the female breast: comparison of 7.5 and 13 MHz]. / Ultraschalluntersuchung der weiblichen Brust: Vergleich von 7.5 und 13 MHz.

PURPOSE: We investigated whether the high resolution ultrasound (13 MHz-scanner) shows smaller lesions and better differentiation than the 7.5 MHz-scanner. METHOD: Prospectively, sonography was performed on forty-seven patients with a 7.5 MHz-scanner as well as with a 13 MHz-scanner in identical slices. RESULTS: Obviously we could obtain more exact diagnoses by using the high resolution scanner. In two patients additional satellite of the primary tumor could be found. In four patients, unclear sonographic findings could be identified as cysts. A disadvantage in the usage of the 13 MHz-scanner is that mastopathy and benign lesions are more difficult to diagnose. With the high resolution more details could be seen although the inhomogeneity as well as the irregularity of the margins are seen more clearly and, therefore, the physician has to reestimate his point of view. To optimize the quality of the pictures made by high resolution ultrasound, it is necessary to regulate the system, which sometimes is quite difficult. CONCLUSION: The recognition of smallest lesions and the reliable presentation of cysts indicates that the 13 MHz-scanner is a good additive diagnostic parameter to the 7.5 MHz-scanner. Therefore, this method may become important for diagnosing multicentrity within carcinomas.

Calibration of measurements in vivo of fluorescein in the cornea.

Quenching of fluorescence of fluorescein is not observed with broad field fluorophotometers. Fluorophotometric equipment which measures the fluorescence in a tiny spot has, however, been reported to underestimate the molarity of fluorescein in the rabbit corneal stroma by as much as a factor of two. In this experiment, quenching was measured in the rabbit cornea with two scanning fluorophotometers. The quenching was measured by four different techniques: (1) by elution of fluorescein, (2) by elution of albumin, (3) by polarization of fluorescence, and (4) by spectrofluorophotometry. It was estimated by all four methods that quenching in the living rabbit cornea with these instruments is approximately 20%. Taken together, the four experiments suggest that the quenching of fluorescence of fluorescein can be explained entirely on the basis of the interaction of fluorescein and albumin in the stroma.

The effects of withdrawal of timolol in chronically treated glaucoma patients.

The dynamics of aqueous humor were studied before and after discontinuing timolol maleate in chronic users. Nineteen patients (mean length of treatment, 44 months) were studied by measuring their baseline intraocular pressure (IOP) and aqueous humor flow during treatment and 2 days to 6 weeks after discontinuing the drug. Flow did not increase significantly until 4 days after discontinuing timolol, and IOP did not increase significantly until 14 days later. Flow did not revert to its normal rate for 2 to 6 weeks. Intraocular pressure was 15% lower and the flow 24% lower during maintenance treatment than 1 month after discontinuing timolol. This comparison demonstrates the efficacy of chronic treatment. Recovery of aqueous flow is slow after stopping timolol. This finding suggests that lower or less frequent doses than are customarily used might be equally efficacious. If timolol is discontinued before filtration surgery, its effects will remain for 2 to 4 weeks.