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Two new stonefly species, Anacroneuria segnini Stark and Maldonado sp. n. and A. cacute Stark and Maldonado sp. n. are described from Venezuela. Nymphal descriptions based on reared specimens are given for A. segnini, A. muesca Stark, A. paleta Stark, two unassociated females, and an additional species being described by colleagues. [ABSTRACT FROM AUTHOR]

Notalina roraima Holzenthal 1986 was described on the basis of a single holotype specimen from the Pantepui Region. The species is a member of the endemic Neotropical long-horned caddisfly (Trichoptera: Leptoceridae) subgenus Notalina (Neonotalina) Holzenthal 1986. We present new records of this species and describe some morphological variation in the male genitalia. Moreover, we describe and illustrate the larva of this species and include information of its habitat. We also differentiate it from N. morsei, the only larva of the subgenus Neonotalina described until now.

Aim of the Study: To evaluate the indications for open surgical biopsy of breast lesions resulting in a benign histologic report., Methods: A consecutive series of 754 benign breast biopsies was collected from six Italian centers previously participating in a multicenter study on the benign/malignant biopsy ratio. Histologic diagnosis, diagnostic tests performed, final clinical diagnosis and the indication for surgical biopsy were compared., Results: Fibrocystic alterations represented the most frequent histologic type (43.2%), followed by fibroadenomas (34.5%). Atypical hyperplasia, phyllode tumors and cancer-like lesions (radial scar, sclerosing adenosis) accounted for a minority of cases. The diagnostic approach was different among centers, with mammography, ultrasonography or cytology being underused in some of them. Suspicion of cancer was an indication for surgical biopsy in 66.7% of cases. In the remaining cases the final report was negative or benign, but biopsy was advised for growing lesions (11.3%) or for cosmetic (3%) or psychological reasons (8.2%). In 4% of cases surgical biopsy was presumably advised for the concurrent influence of high-risk conditions such as previous breast cancer (0.7%), family history of breast cancer (2%) or contralateral synchronous breast cancer (1.3%). In 6.8% of the cases biopsy was advised elsewhere for unknown reasons. The indications for biopsy differed among centers, with one center having a low rate of suspicious cases (37%) and a high rate of reported "cosmetic" or "psychological" reasons (47%)., Conclusions: Leaving aside differences in diagnostic approach and aggressiveness, two thirds of all lesions were biopsied in order to exclude cancer. The routine use of a more complete diagnostic protocol and/or alternative methods to obtain a histologic diagnosis (e.g. core biopsy) might substantially reduce the need for open surgical biopsy.

The role of Doppler techniques in the differential diagnosis of benign from malignant solid breast lesions remains to be defined; indeed, it is still debated whether the diagnostic findings of Doppler US add further information to mammographic and B-mode US results. We investigated the diagnostic effectiveness of Doppler techniques in the differential diagnosis of breast nodules, especially in a selected group of patients with questionable diagnosis because of atypical morphological features or benign appearance detected in women over 40 years old. Color Doppler studies were performed on 111 breast nodules with solid features at US; 53 vascularized lesions were also studied with duplex Doppler. All the nodules were submitted to biopsy, which demonstrated 6 nonvascularized lesions to be complicated cysts. There were 105 solid breast nodules (65 benign and 40 malignant). Color Doppler US showed vascular signals in 71% of benign nodules, mainly at the periphery. 12% of benign nodules had Doppler signals of malignancy at color Doppler US; 92% of malignant lesions was vascularized, with irregular intratumoral signals in 37% of them. The peak systolic velocity and the resistive index were higher in malignant tumors (p < 0.02); peak systolic velocity changed in malignant lesions according to tumor size (p < 0.01). Color Doppler correctly suspected malignancy in 62% of the nodules with questionable features; conversely, 31% of the nodules with questionable findings and no color Doppler signs of malignancy proved malignant at biopsy. In conclusion, the role of Doppler studies remains currently limited in the differential diagnosis of solid breast lesions.

To compare the diagnostic value and the role of plain radiographic magnification and of ultrasonography (US) in breast cancer evaluation, 83 malignant tumors were studied with mammography, plain radiographic magnification and US. Microcalcifications were not included in our study. All tumors subsequently underwent histology or cytology. In our series, the malignant nature of the lesion was unquestionably proved in 53% of cases while a possible malignancy was suspected in 36% and a benign nature was incorrectly suspected in 11% of cases with mammography. The diagnostic value of plain radiographic magnification was compared with that of US; breast patterns, mammographic and clinical findings were considered. As for breast patterns, plain radiographic magnification was more accurate in evaluating fatty breast than both mammography and US, allowing the correct diagnosis of 58% of questionable mammographic findings, vs. 33% of US. On the contrary, US was more accurate in dense breasts, allowing the correct diagnosis of 77.7% of mammographic misdiagnoses vs. 33.3% only of plain radiographic magnification. As far as mammography is concerned, US was more accurate than plain radiographic magnification in the assessment of round masses (71.4% vs. 38.1%, respectively), whereas plain radiographic magnification was more accurate than US in stellate masses (100% vs. 92.7%, respectively). As far as clinical findings are concerned, plain radiographic magnification sensitivity was substantially the same in the assessment of symptomatic and asymptomatic lesions (91.5% vs. 89%, respectively), whereas US sensitivity was higher in symptomatic (97%) than in asymptomatic (69%) lesions. The rate of false-negative US diagnoses (14.4%) was higher than those of mammography and of plain radiographic magnification. Negative US findings must be considered with caution and are not sufficient to settle a radiologic doubt.

Recently, 20 breast centers in Friuli Venezia Giulia have been investigated for the mammography optimization program known as DQM (Dose and Quality in Mammography). This was the second trial, the first one dating 1987-1988 and including only 10 centers. The chosen parameters were evaluated by means of a performance phantom containing 15 details, a Victoreen 660 ionizing camera, a star pattern and several plexiglass phantoms of different thickness. Statistical-methodological data were collected by means of a questionnaire. The results of the trial were communicated to each center as well as directions for future improvements. All centers were found to use mammographic equipment with a molybdenum anode and the film-screen combination; 18 center use grids daily, while 11 can perform direct radiographic magnification. Only 40% of the examined centers use a dedicated daylight printer. The overall quality of the radiographic image was seen to be acceptable, as 8 or more details of 15 hidden in the phantom were visualized, in 16 of 20 centers. The mean glandular dose was below the minimum threshold in all centers: in 45% of cases it was below 1.5 mGy. The setting of the automatic exposition control system was found to be poor, especially that of the adjustment related to breast thickness. Acceptability thresholds were met only by 31% of the examined centers (density variations < 20%). Notwithstanding the identification of areas where improvements can be made also from a methodological point of view, we can conclude that the quality provided by regional breast centers is definitely adequate. Good image quality and acceptable doses were observed in 80% of the centers. The results are significant and encouraging when compared with those from the first DQM trial carried out in our region, which confirms the value of periodical quality programs.

The US findings in the kidneys of diabetic patients were studied. Diabetic subjects without clinical or laboratory signs of nephropathy were investigated by means of US in order to detect early anatomical lesions predictive of renal injury. The kidneys of cadaver diabetics were also studied to correlate US and histologic patterns. US alterations were observed in half of the cases: they were diffuse in 9% of cases and focal in 39%--hyperechoic spots and hyperechoic juxta-medulla. Focal spots are more common in juvenile-onset diabetics and they are correlated with the age of diabetes. At histology the above US patterns were correlated with the vascular wall alterations typical of diabetic nephropathy. Diffuse alterations are not specific. The authors conclude by suggesting US as a prognostic test for diabetic nephropathy.

US plays an extremely important role in the diagnosis of renal masses. However, a number of diagnostic difficulties still exists in both identification of the mass and definition of its nature. The most frequent causes of diagnostic errors are discussed. Errors may be due to the radiologist, to technical limitations, and to the lesion itself. The radiologist is responsible for inexperience and negligence (incorrect application of the technique, limited clinical information, poor knowledge of US findings). Technical limitations are due to poor spatial and contrast resolution, to extremely fat patients, and to artifacts. As far as lesions are concerned, cystic and solid masses must be distinguished, since the problems are different. As for cystic lesions, problems are relative to their visualization and to the definition of their nature in cases of atypical or complex cysts, due to the complexity of some US findings. The latter involve both cystic wall and content and are related to calcifications, septa, vegetations, blood, purulent debris. In case of solid masses, problems concern the identification of small renal tumors, the differentiation among the various anatomical variants, the differential diagnosis of benign from malignant tumors, and the evaluation of tumor extent. The authors conclude that, whereas operator-dependent errors can be avoided, those inherent to technical parameters and to the lesion itself represent the diagnostic limitation of US.

In recent years some structures or features such as the "inter-renuncular septum", the "echogenic triangle" and the "echogenic line" have been described to support the concept of a kidney resulting from the fusion of two masses or renunculi. To clarify this concept and to understand the meaning of the above echographic features better, the authors have examined prospectively by sonography the kidneys of 50 children, 200 adults with a single collecting system, 25 adults with a duplicated collecting system and 32 cadavers. Furthermore, to help explain the sonographic features, we have examined 32 cadaver kidneys with sonography and 10 cadaver kidneys with magnetic resonance imaging (MRI). The sonographic, MRI and anatomical correlations have shown that the "echogenic triangle" and the "echogenic line" are not renuncular residuals, but simply an extension of the hilar fat visible when the renal sinus is rather deep. The intermediate cortical mass is not a septum dividing the kidney into an upper and lower renunculus, but a column of parenchymal tissue crossing the renal sinus, which, from an anatomical point of view, is an accessory renal lobe. The presence of two renunculi, suggested in a previous study with cortical nephrotomography, has not been confirmed.

A new technique of mictional cystourethrography has been developed. The examination is performed with the patient sitting on a radiolucent chair with the feet high on a footstool, in order to avoid the superimposition of the femoral heads in the lateral projection. Fifty patients were examined, 26 of whom were continent and 24 incontinent. The technique allowed the evaluation of the site of the bladder neck, of vesico-urethral angles, and of the urethra. The investigation made it possible to obtain accurate information on the position of the vesical floor relative to the inferior margins of the obturator foramina. It was thus possible to correlate the position of the bladder floor with the clinical symptomatology: in our experience the position of the bladder floor was higher in incontinent that in continent patients. A low position of the bladder baseplate was usually associated with incontinence. Other parameters turned out to be less specific. This paper emphasizes the simplicity and the reproducibility of our technique, which allows a reduction of X-ray exposure dose.

The authors evaluated 177 cases of expansive lesions observed in diffusely dysplasic breast. The size of the lesions was less or equal to cm 2. They found that mammography had its diagnostic difficulties in benign lesions such as fibroadenomas and fibrocystic disease. Ultrasonography was carried out on 106 of those patients. The sensitivity of ultrasonography was the same for the definition of benign and malignant lesions. Moreover, it was not modified by the diffuse dysplasia.

Ecological energetics of Chaoborus brasiliensis from Lake Valencia, Venezuela, were studied between February 1979 and February 1980. Direct measurements were made of the respiration rate, assimilation efficiency, and growth rate of all 4 larval instars and of the pupae. For the larval stages, respiration increased as the 0.67 power of body mass. Respiration rates of the larvae, when corrected for body size and temperature, were extraordinarily low by comparison with the rates for most aquatic insects. The respiration rates of pupae were 3 times as high as those of larvae the same size. Assimilation rates increased significantly with body size for the larvae and differed slightly but significantly among food types. Assimilation efficiencies fell within the expected range for carnivores. The growth efficiencies were exceptionally high for instars II-IV by comparison with other small aquatic organisms. High growth efficiency for Chaoborus brasiliensis, and possibly for Chaoborus generally, is explained by a very low maintenance cost and may be a significant explanation for the wide distribution and high degree of ecological success in this primary carnivore of plankton communities.

The purpose of our study was to compare the ultrasound findings in malignant breast masses (which underwent biopsy) with their histological appearance. In our activity of breast sonography, we observed that the same histological type of breast cancer often shows a different ultrasonic image. The main difference concerns the sonic attenuation or increase through the neoplastic mass. The histological examination took into account the amount of stroma and cells and the architectural pattern of the lesion. Comparing these features with the ultrasonic image, it has been shown that sonic transmission is related more to the architectural pattern than to the fibrous content of the neoplastic tissue.

It is widely known that an early detection of breast cancer, when still asymptomatic, can improve the prognosis. Screening is thus suggested, and mammography should be the methodology of choice. Therefore, we tried to evaluate the best mammographic approach to the screening of breast cancer. Since January 1st, 1986, we have changed our mammographic procedures: the results obtained have been compared with those previously acquired. Through the evaluation of the different parameters we observed that: 1) the best results in patients screened for the first time can be obtained by using the cranio-caudal and the oblique mammographic views; 2) in the follow-up the oblique view can be used alone--which must then be compared with the oblique view of the first exam. This new mammographic approach makes it possible for us to reduce the exposure-dose to the patient and to the population, as well as the time and the cost of the screening. Moreover, the number of examinations can be increased by 20%. These results are extremely interesting, since mammography is now as sensitive as ever.

An evaluation of the urethra has been made in patients who underwent open surgery or endoscopic resection of the prostate, by means of transrectal echography (EG). The technique used is described; studies have been performed both in basal conditions and in various functional phases, including micturation. Echographic findings are compared to those achieved with micturating cystourethrography (MCU). In case of total prostatectomy EG and MCU findings are similar, showing the surgical bladder neck and the urethral aspect even during micturation. EG shows furthermore possible liquid fluid collections. In partial prostatectomies EG and CUM findings differ, showing the first, besides the site of the surgical intervention, the possible presence of calculi, while CUM findings do not differ from those visible in total prostatectomies. Conclusions are that for the whole study of the urethra CUM is necessary, while for the study of the prostatic region EG gives more information. Therefore EG is proposed as method complementary to CUM in the evaluation of the proximal urethra.