[Magnetic resonance with an endorectal coil and a fast spin echo sequence in the staging of prostatic carcinoma. The correlation with histopathological data]. / Risonanza Magnetica con bobina endorettale e sequenza Fast Spin Echo nella stadiazione del carcinoma prostatico. Correlazione con i dati istopatologici.

INTRODUCTION: We investigated the accuracy of endorectal coil Magnetic Resonance Imaging (MRI) and Fast Spin Echo (FSE) technique in staging prostate cancer. MATERIAL AND METHODS: MRI was performed in 70 patients with biopsy proved prostatic cancer. A total of 33 patients subsequently underwent radical prostatectomy. T2-weighted FSE sequences (TR 3400-4100, TE 120, Echo train length 13) were acquired in all patients. Axial, sagittal and coronal 4-5 mm images were obtained with 13-14 cm field of view and 256 x 256 matrix. Additional T1-weighted spin echo images were acquired in 9 patients. Lesion staging on MR images was performed according to the American Urological System. MR data were compared with the pathologic findings of whole-mount sections of the surgical specimens. RESULTS: Overall accuracy for endorectal coil MR imaging was 60%; ten cases were underestimated and 3 cases were overestimated. The sensitivity and the specificity of endorectal coil MRI in diagnosing capsular penetration were 77% and 81%, respectively. Seminal vesicle invasion was detected with 87% sensitivity and 96% specificity. CONCLUSIONS: Endorectal coil MRI provides a more accurate preoperative local staging.

[Evaluation of total and inflated lung volumes by a quantitative study using computerized tomography in patients with acute noncardiogenic pulmonary edema (ARDS)]. / Valutazione dei volumi polmonari totali e aereati mediante lo studio quantitativo con tomografia computerizzata nei pazienti con edema polmonare acuto non cardiogeno (ARDS).

Our study was aimed at developing a method to assess lung volumes and relative percentages of well-inflated lung parenchyma in Adult Respiratory Distress Syndrome (ARDS) patients by processing conventional CT examinations of the lung and at investigating the prognostic value of CT findings. Fourteen patients (5 women and 9 men, age range: 35-79 years) admitted to the intensive care unit January, 1992, to June, 1994, because of severe ARDS, and with lung injury scores exceeding 2.5, were submitted to CT. A homologous group of 14 patients matched for sex and age and with normal lungs was examined as a control group to investigate the accuracy of our method. Two examinations were obtained in 7 of 14 ARDS patients; the trend of lung volumes and of the relative rates of well-inflated parenchyma could thus be calculated. During the examination, we maintained in all ARDS patients the same ventilatory pattern used in the intensive care unit. Consequently, in 18/21 examinations scans and respiratory phases were not correlated. In the control group no statistically significant differences were observed between the scans obtained with (inspiratory apnea) and without coordination with the respiratory phase. As for lung volumes, our results in normal subjects showed a good correlation with normal spirometric data. In ARDS patients lung volumes, although reduced, did not correlate with prognosis. As for the percentage of well-inflated parenchyma in ARDS patients, we observed a good correlation with prognosis in the patients submitted to two examinations and, in all patients, a good correlation with D(A-a)O2 index (p < 0.05), PaO2/FiO2 index (p < 0.005) and with the rate of arteriovenous shunt (p < 0.001). In conclusion, our results show that CT of the lung is a reliable and repeatable method for the functional assessment of the lung in ARDS patients.

[CT-guided thoracic biopsy. Personal experience with DBNH Haaga 20 G needles]. / Biopsia toracica TC-guidata. Esperienza personale con ago tipo DBNH 20 G.

CT-guided fine-needle biopsy of the chest is nowadays a conventional diagnostic procedure, which can be furtherly improved so as to increase its diagnostic sensitivity and to reduce complications. We studied a series of possible improvements over a 2-year period (1990-1992). In our radiology department 164 CT-guided biopsies were performed in 130 men and 34 women. DBNH Haaga 20-G (15 cm) needles (Cook, Denmark) were used. This kind of needle is a coaxial cutting-edge needle used for simultaneous cytological and histological sampling. Exams were performed with a Philip Tomoscanner CX-S (scanning time: 2.8 seconds). Of 164 tissue samples, 153 (93.4%) were adequate for histological diagnosis. As for suspected neoplastic disease, our results demonstrated 108 true positives, 27 true negatives, 18 false negatives and no false positive. Sensitivity, specificity and diagnostic accuracy were 85.7%, 100% and 88.2%, respectively. In 24 cases there were minor complications--i.e., 5 cases of parenchymal hemorrhage and 19 cases of minor pneumothorax. In one case only there was major pneumothorax which required surgical drainage. On the basis of our experience, we suggest the use of such coaxial catheters as the DBNH Haaga type for the collection of both histological and cytological material because this needle reduces the need for repeated invasive and potentially dangerous maneuvers.

[Echography applied in dermatologic diseases. A comparative preliminary study of the use of high-frequency transducers]. / L'ecografia applicata alle malattie dermatologiche. Studio preliminare comparativo sull'impiego delle sonde con elevata frequenza.

Ultrasonography (US) was first used in dermatology in 1979. During the last few years, US has evolved thanks to technological progress and its use has been on the increase, in dermatology, to study both localized and diffuse skin diseases. In this paper, the authors review and compare the results obtained with a 20 MHz transducer with those obtained with 7.5 MHz and 10 MHz transducers in the study of skin alterations. Three parameters were considered: lesion identification, spatial evaluation and US structure. Fifty-eight cases of localized and 48 of diffuse skin diseases were examined. The localized forms were benign in nature in 18 patients (3 nevi, 2 seborrheic keratoses, 3 ulcus cruris cases, 6 sebaceous and 2 liquid cysts). The other 40 patients had malignant neoplastic lesions (16 epitheliomas, 13 primitive melanomas, 1 metastatic melanoma, 8 lymphomas and 2 Kaposi's sarcomas). The 48 cases of diffuse conditions included 27 systemic sclerosis, 18 psoriasis and 3 lichen planus cases. The comparative analysis of the results obtained using the different types of transducers in the study of localized dermatoses showed no differences in lesion identification and in the depiction of their US features. On the other hand, the 20 MHz transducer was much more accurate than the others as regards the spatial evaluation of the lesions measurable in millimeters, whereas it poorly demonstrated the lesions > 1.5 cm. However, only the 20 MHz transducer could demonstrate the US features of diffuse conditions.

Conflicting aspects of renal leiomyoma with different imaging techniques.

A case with benign renal leiomyoma examined by all the imaging techniques currently available is described. The aspects were conflicting, particularly with regard to sonography and magnetic resonance imaging, and the sole technique which provided more reliable information was the CT scan.

[Preoperative staging of rectal carcinoma by transrectal echography combined with pelvic computerized tomography]. / Staging preoperatorio del carcinoma rettale tramite ecografia transrettale associata a tomografia computerizzata della pelvi.

The accurate staging of rectal carcinoma is very important for treatment planning. The histological data obtained from the surgical specimens of 22 patients with rectal carcinoma were compared with pre- and postoperative endorectal US findings and with preoperative CT results. According to an adapted version of the Astler and Coller classification, the different degrees of tumor spread into the rectal wall were represented as follows: stage A: 1 patient; stage B1: 5 patients; stage B2: 6 patients; stage C1: 1 patient; stage C2: 8 patients and stage D: 1 patient. Preoperative staging, based on the overall results of CT and US, was in agreement with histology in 19 of 22 cases. Individual analysis of US and CT results, in comparison with histological data, showed US staging accuracy to be 77.3% (17/22 patients). US accuracy in demonstrating tumor spread into the rectal wall (stages A, B1, C1) was 100% (7/7 patients); US was 70% accurate in lymph node detection (7/10 patients) and 93.3% accurate in demonstrating perirectal infiltration (14/15 patients). CT diagnostic accuracy was 66.7% (10/15 patients) in the evaluation of perirectal lymph nodes, but tumor spread into the rectal wall (stages A and B1) could not be evaluated. While admitting the primary role of US in the staging of rectal carcinoma, according to our results a combination of US and CT yields a more accurate preoperative diagnostic picture.

Mutual contact of murine erythroleukemia cells activates depolarizing cation channels, whereas contact with extracellular substrata activates hyperpolarizing Ca2+-dependent K+ channels.

This study deals with the modulation of the plasma membrane potential (delta psi p) of murine erythroleukemia (MEL) cells by cell-substratum or cell-cell contact. delta psi p was determined by measuring the distribution of tetraphenylphosphonium (TPP+) across the plasma membrane; it appeared strongly, and inversely, influenced by the two types of cell contacts. Contact with the culture surface produced a delta psi p hyperpolarization directly proportional to average distance among the ideal centers of the cells on this surface (d) within the range 10-80 microns. A detailed mathematical analysis of the function delta psi p = f(d) is presented, as well as experiments involving the use of ionophores (valinomycin and A23187) and the conditioning of the culture surface. We concluded that the d-dependent hyperpolarization (dDH) was the result of a complex interplay between the activating properties of substratum on Ca2+-dependent K+ channels (KCa) and some substratum-adherent factors that are shed by MEL cells and antagonize KCa activation (substratum-attached cellular factors = SACF). By contrast, contact of the cells with each other, obtained by incubating MEL cells at d smaller than the average cell diameter (phi = 10 microns), produced a marked delta psi p depolarization. This intercellular contact-dependent depolarization (ICDD) was unaffected by valinomycin; it was abolished by substituting Na+ in the external medium with a nondiffusible cation (choline), which shows that ICDD was sustained by Na+ influxes, probably mediated by stretch-activated (s.a.) cation channels.

Commitment to differentiation of murine erythroleukemia cells involves a modulated plasma membrane depolarization through Ca2+-activated K+ channels.

The role of the plasma membrane potential (delta psi p) in the commitment to differentiation of murine erythroleukemia (MEL) cells has been studied by analyzing the ionic basis and the time course of this potential in the absence or the presence of different types of inducers. delta psi p was determined by measuring the distribution of tetraphenylphosphonium (TPP+) across the plasma membrane and displayed a 22-hour depolarization phase (from -28 to +5 mV) triggered by factors contained in foetal calf serum (FCS) and followed by a nearly symmetrical repolarization phase. After measuring the electrochemical equilibrium potential of Na+, K+, and Cl-, the relative contribution of these ions to delta psi p was evaluated by means of ion substitution experiments and by the addition of ion flux inhibitors (tetrodotoxin [TTX], 4-acetoamide-4'-isothiocyanostilbene-2,2'-disulfonate [SITS]) and ionophores (Valinomycin, A23187). The Na+ contribution to delta psi p appeared negligible, the potential being essentially generated by K+ and Cl- fluxes. When evaluated by a new mathematical approach, the effects of Valinomycin and A23187 at different times of incubation provided evidence that both the depolarization and the repolarization phase were due to variations of the K+ permeability across the plasma membrane (PK) mediated by Ca2+-activated K+ channels. All the inducers tested (dimethylsulfoxide [DMSO], hexamethylen-bis-acetamide [HMBA], diazepam), although they did not modify the ionic basis of delta psi p, strongly attenuated the depolarization rate of this potential. This attenuation was not brought about when the inducers were added to noninducible MEL cell clonal sublines. Cell commitment occurred only during the depolarization phase and increased proportionally to the attenuation of this phase up to a threshold beyond which the further increase of the attenuation was associated with the inhibition of commitment. The major role of the inducers apparently consisted of the stabilization of the Ca2+-activated K+ channels, suggesting that a properly modulated delta psi p depolarization through these channels is primarily involved in the signal generation for MEL cell commitment to differentiation.