Direct integration of the inverse Radon equation for X-ray computed tomography.

A new mathematical appoach using the inverse Radon equation for restoration of images in problems of linear two-dimensional x-ray tomography is formulated. In this approach, Fourier transformation is not used, and it gives the chance to create the practical computing algorithms having more reliable mathematical substantiation. Results of software implementation show that for especially for low number of projections, the described approach performs better than standard X-ray tomographic reconstruction algorithms.

The characterization of flow signals from tubal and ovarian arteries using intraoperative continuous wave Doppler.

Ovarian vascular Doppler is a promising screening test for early ovarian cancer detection. However, disagreements on flow indices used, flow signal shapes and ovarian vessel localization cause continuing controversy. We aimed at clarifying some of this confusion by directly measuring the adnexal arterial blood flow during laparotomy. A 10-MHz continuous Doppler probe was used to examine adnexal vessels in 24 patients undergoing laparotomy for benign gynecological pathology. Resistance (RI) and pulsatility (PI) indices were calculated for each vessel and the shape of the flow signals was noted. The tubal arteries showed a low-velocity flow pattern with relatively high end-diastolic flow when compared to the ovarian artery signals obtained from the infundibulopelvic ligament.The mean RIs for the tubal artery and ovarian artery in the infundibulopelvic ligament were 0.59 +/- 0.02 and 0.73 +/- 0.02, respectively. The mean PIs for the tubal and ovarian artery in the infundibulopelvic ligament were 1.11 +/- 0.09 and 1.53 +/- 0.1, respectively. The tubal artery showed a significantly lower RI and PI when compared to the ipsilateral ovarian artery at the infundibulopelvic ligament (p < 0.001 and p = 0.002, respectively) and its hilar branches (p = 0.03 for RI and p = 0.03 for PI). We conclude that tubal artery flow signals, which are measured directly for the first time in this study, are characteristic and are distinct from the ovarian artery signals. Tubal artery signals might be erroneously picked up during transvaginal color Doppler sonography of the ovaries, especially in the presence of conditions causing a decreased impedance to blood flow in the pelvis, such as ovarian tumors. Recognizing the flow signal from the tubal artery may help in differentiating ovarian and tubal vessels detected during color Doppler sonography.

Endometrial and myometrial thickness and uterine blood flow in postmenopausal women: the influence of hormonal replacement therapy and age.

The aim of our study was to assess the age and hormonal influence on endometrial and myometrial thickness and uterine blood flow in postmenopausal women. One hundred and nine healthy postmenopausal women were examined by transvaginal ultrasonography and color Doppler ultrasonography. Twenty women (18.4%) were under continuous HRT for at least 1 year. In all patients, full thickness of the endometrium and half thickness of the myometrium was measured. Pulsed Doppler waveforms were used to calculate the RI for the left and right uterine arteries. Endometrium thickness in the groups without HRT did not change as the years of postmenopause progressed. This was also true for myometrial thickness. The resistance to blood flow in the uterine arteries remained the same as the postmenopause progressed, but with each 5 year analysis, the ability to see the uterine arteries decreased. The duration of the therapy did not affect the measured parameters. The thickness of the endometrium was larger in the groups with HRT in comparison with all groups without HRT (P < 0.01). Myometrial thickness and uterine blood flow are not affected and did not show any significant influence from HRT. In conclusion, continuous HRT significantly influences the thickness of the postmenopausal endometrium but not of the myometrium or the uterine artery blood flow.

[Synchronous multiple primary cancers of the colon]. / Cancere multiple primare sincrone ale colonului.

The authors report three cases with double synchronous primary cancers of the large bowel, representing 1,57% of the total 224 cases with colon and rectal cancers they have operated. In all the cases it was possible to perform surgical removal of the tumours by right hemicolectomy and segmental sigmoidectomy in two of the patients and rectosigmoidectomy in the third one. The clinical and prognostic characteristics confirmed the opinion, that has been advanced in the specialized literature, that these tumours are relatively benign.

[Unusual clinical and therapeutic aspects of intrathoracic goiter]. / Aspecte clinice si terapeutice particulare în gusile intratoracice.

Out of the 220 cases of goiters operated in the clinic 19 were partially or totally intra-thoracic, as follows: --totally intra-thoracic: 7 cases; --partially intra-thoracic: 12 cases, of which: mediastino-cervical: 2 cases; cervico-mediastinal: 10 cases. Five of the totally intra-thoracic goiters were in the anterior mediastinum, while two were in the posterior mediastinum, in a retro-oesophageal position. Three of the 19 intra-thoracic goiters were malignant. The symptomatology, the diagnosis and especially the therapeutical attitude are discussed.