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Graves disease is an organ-specific autoimmune disorder characterized by variable clinical and laboratory patterns and by alternating remissions and relapses. We investigated if a correlation exists between the hypervascular pattern of Graves disease, studied with color Doppler US (CDUS), and the degree of thyroid hyperfunction, estimated according to biohumoral parameters. We also investigated if CDUS can differentiate, with the help of pathologic correlations, the glandular histologic patterns recently reported in the literature in thyroidectomized patients. Forty-five patients with Graves disease were selected and submitted, in the same day, to CDUS and to a clinical biohumoral test, including hormone and antibody assays. Eight of these patients had undergone total thyroidectomy. The following variables were studied in each patient: US structure and glandular thickness, color spot distribution, VP, R1, T3, T4, TRab, Tmab, Tgab and patient's age. Thirty-three normal volunteers were also examined. CDUS demonstrated two patterns: pattern A consisted in many homogeneous and bilobed color spots all over the glandular structure; pattern B consisted in color spots areas and/or vascular bands surrounding avascular areas. Pattern A was seen in 13/45 patients (28.9%) and pattern B in 32/45 (71.1%). The subdivision into two groups showed significant differences from a statistical point of view (0.05 > p > 0.001) in relation to the following indices: Vp, T3 and gland size. Of the 8 patients submitted to total thyroidectomy, 3 had pattern A and 5 had pattern B at CDUS. Histology showed major differences between the two groups: thus, thyroidectomized patients with pattern B had thickened interlobular septa and more nodules. with reduced vascular component. Our study confirms that CDUS can diagnose hyperthyroidism; moreover, this technique seems to be capable of differentiating, with the help of color and flow velocity analyses, two different abnormal patterns, which we called A and B. The early results of this preliminary study seem to indicate that CDUS can show two distinct patterns of Graves disease, which differ from a histologic viewpoint and probably also in clinical aggressiveness.

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The goal of the study was to verify if echographic fine needle biopsy (US-FNB) improved the diagnostic accuracy of thyroid nodules with respect to a "blind" technique (B-FNB). The study group involved 6,693 patients who underwent aspiration biopsies (989 males and 5,704 females; mean age 46.3 +/- 13.7; range 5-88 years). Total biopsies were 7,952 as some patients underwent two or more biopsies in different nodules. 7,324 nodules with B-FNB and 628 nodules with US-FNB were studied; in this latter cases 136 nodules were not palpable. The diagnosis of malignancy was higher in US- FNB than B-FNB. However, non-diagnostic samples were more prevalent in US-FNB with respect to B-FNB. A histological diagnosis was available in 27 patients with US-FNB and 379 with B-FNB. In US-FNB, accuracy was 81.8%, sensitivity 86.6% and specificity 77.7%. In B-FNB, accuracy was 80.6%, sensitivity 85.1% and specificity 78.1%. These data show that US-FNB diagnostic accuracy was not better than B-FNB. The higher incidence of malignancy found in US-FNB was not dependent on better accuracy, sensitivity or specificity of the US-FNB technique with respect to the B-FNB examination. It is possible that the higher number of malignancies in patients studied with US-FNB was due to the fact that the US-FNB technique aspirated smaller nodules and particular areas of echographic suspicion, thus increasing the possibility of finding a malignancy. Based on our data, we feel that US-FNB results in a greater number of diagnostically inadequate samples. This may depend in part on the smaller size of the biopsied nodules (which are relatively more vascular than larger nodules) and in part on the greater difficulty in carrying-out this technique which directed towards particular echographic areas of suspicion resulting in greater biopsy blood contamination. The authors feel that US-FNB should be carried-out in all cases of non-palpable nodes found incidentally so as to rule out malignancy.

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To date, Doppler US has been rarely used to diagnose chronic renal transplant rejection because of its low sensitivity. Nevertheless, all the results have been obtained from the analysis of flow-metric indices, mainly considering the diastolic phase of the Doppler waveform, e.g., the resistance index (RI) and the pulsatility index (PI). This study was aimed at investigating if Doppler diagnostic accuracy in renal transplant monitoring can be increased by studying the systolic phase, considering peak arterial systolic velocity (Vp), acceleration time (AT) and acceleration index (AI). Seventy-six renal transplant recipients were examined with color-Doppler and duplex Doppler US, which showed 47 well-functioning and 29 hypofunctioning kidneys. The diagnosis was confirmed with perfusion scintigraphy with 99mTc DTPA, biopsy and 6-month clinical-laboratory follow-up. The means of Vp, AI, AT and RI relative to the group of patients with normal renal function were compared with those in the group of patients with chronic rejection. Critical values were measured at the segmental arteries (Vp = 70 cm/s, AI = 7 m/s2, AT = 100 ms), at the interlobar arteries (Vp = 45 cm/s, AI = 4 m/s2, AT = 100 ms) and at the arcuate arteries (Vp = 35 cm/s, AI = 3 m/s2, AT = 100 ms). On the basis of these values, normal functioning transplants were differentiated from hypofunctioning ones. RIs were altered (> 0.75) in 8 of 17 chronic rejections and in 3 of 47 normal transplants, with 47.1% sensitivity and 93.6% specificity. The combination of RI with Vp and AI strongly increased both sensitivity (100%) and specificity (82.98%). Combined AI and RI exhibited 94.1% sensitivity and 89.3% specificity. In conclusion, the indices of the ascending systolic phase, in peripheral vascular samplings, are clearly more efficacious than RI alone and index combination exhibits the highest diagnostic accuracy.

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This study was aimed at investigating role and efficacy of color-Doppler US in the characterization of thyroid nodules. Eight-three consecutive patients with only one solid thyroid nodule, not smaller than 0.8 cm, were examined. They were submitted to scintigraphy and laboratory tests first and then to color-Doppler US, to fine-needle biopsy and/or to histologic examinations. Color-Doppler US examinations were performed with a 7.5 MHZ linear probe, 5-MHz Doppler frequency, PRF = 0.8 KHz, 40-50 degrees insonation angle, wall filters at the lowest level, 2-5 mm sample volume, color and Doppler gains set at 30-50% and asynchronous data collection. The final diagnosis, made at cytology and/or histology, showed 43 follicular hyperplasias, 19 follicular adenomas and 21 carcinomas. The following US variables were considered: nodule size, site, margins and the possible presence of the "halo sign" pattern, with a special attention paid to micro-/macrocalcifications, signs of invasion of surrounding anatomic structures and possible adenopathies. With color-Doppler US, we studied presence and distribution of nodular vascularization, peak (Vp) and middle (Vm) velocity, resistive index (RI) and Doppler spectrum morphology. In agreement with the current literature, 3 patterns of nodular vascularization were considered: not apparent, or type I (3/83), which was found only in follicular hyperplasia; peripheral, or type II (46/83) and finally, peri- and intranodular, or type III (31/83). Hyperplasias exhibited a type I pattern rarely and exclusively and, if vascularized, they always exhibited Vp < 50 cm/s, Vm < or = 40 cm/s and mostly (39/40 RI < or = 0.75; adenomas were always vascularized, with Vp > 50 cm/s and mostly (18/19) RI < or = 0.75; primary or secondary tumors were always vascularized, with an extremely variable distribution, and if Vp < 50 cm/s, their RI > 0.75, while if Vp < 50 cm/s, their RI was independent of the threshold value of 0.75. These preliminary conclusions seem to confirm that vascular patterns alone are not particularly helpful, compared with B-mode US results, in distinguishing among thyroid nodules. Nevertheless, Vp and RI may be of great usefulness in the characterization of solid nodules and in the selection of the patients to submit to fine-needle biopsy.

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This study was aimed at finding a Doppler parameter to distinguish, among medical nephropathies, the ones with glomerular from those with vascular or tubulointerstitial involvement. Therefore, 32 patients (20 men and 10 women, average age: 43 years, range: 10-77 years) with clinical and laboratory signs of medical renal disease were examined with color-Doppler US. The resistive index (RI, n.v. < 0.70), as calculated from the Doppler waveform signal was especially considered to assess eventual significant changes differentiating renal diseases according to the different kinds of involvement. RI values were compared with renal biopsy findings, creatininemia levels and clinical and laboratory variables as hematuria and proteinuria. Histology diagnosed 18 glomerulonephritis, 4 glomerulonephritis with interstitial involvement and 10 vascular and tubulointerstitial nephroses, with 1 tubular necrosis. Doppler US demonstrated a normal RI value in 17/18 patients with glomerulonephrosis (mean value: 0.59 +/- 0.05). In one case only, even though biopsy indicated the involvement of one glomerulus only (membranous GN II stage), RI was high--i.e., 0.79. In 4 patients with simultaneous glomerular and interstitial involvement, the mean RI value was 0.17 +/- 0.01. In the 10 cases of tubulointerstitial or vascular nephrosis, the RI was 0.83 +/- 0.07. As far as the correlation between creatininemia levels and RI is concerned, in 8 patients with high values (1.5-8 mg/dl), the mean RI was 0.72 +/- 0.08 and only a weak correlation was found between the RI and the renal failure degree as expressed by creatininemia levels. Therefore, the RI seems to be related more to the site of the disease in the renal field than to renal failure degree. Doppler US seems to be capable of characterizing medical nephrosis, distinguishing glomerular from vascular or tubulointerstitial involvement. In this application area, the combined use of Doppler and color-Doppler US allowed each examination to be performed in a relatively short time--i.e., 30 minutes on the average.

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