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Biomedical subjects

L Solbiati

Publications and source records attributed to L Solbiati.

At least 19 recordsLinked to original sources
PubMed1992

Carotid body tumors: US evaluation.

The ultrasound (US) findings in 20 patients with 23 carotid-body chemodectomas were reviewed. Twenty-two of 23 tumors could be seen at US; the remaining lesion could not be differentiated from surrounding enlarged lymph nodes resulting from thyroid cancer. The lesions were solid, slightly heterogeneous masses that ranged in size from 1.2 to 5.0 cm and were located within the carotid bifurcation. Pulsed Doppler analysis of blood flow within the tumor mass was possible in eight patients with nine chemodectomas, and low-resistance waveforms were obtained from multiple sites within the mass in all cases. The diagnostic possibility of a chemodectoma has to be considered when a solid mass is detected within the carotid bifurcation. On the basis of these findings, as US diagnosis was possible in 18 of 20 patients in the authors' series. Doppler analysis of the mass to evaluate intratumor blood flow is helpful in differentiating chemodectomas from other solid, nonhypervascular masses.

Adult↗
PubMed1992

Ultrasound-guided percutaneous fine-needle ethanol injection into parathyroid glands in secondary hyperparathyroidism.

To reduce parathyroid hormone concentrations in uraemic patients refractory or hyporesponsive to calcium supplements and active metabolites of vitamin D, we developed in 1982 a new parathyroid ablative technique consisting of percutaneous fine-needle ethanol injection (PFNEI) into enlarged parathyroid glands under ultrasonic guidance. Fifty uraemic patients have been treated. Decreases in carboxy terminal parathyroid hormone (PTH) were 50% or more in 13 of 50 patients followed up (26%) at 1 month, in 13 of 48 (27%) at 6 months, and in 9 of 25 (36%) at 12 months. Decreases of 30% or more in PTH were obtained in 21 of 50 (42%), in 25 of 48 (52%), and in 15 of 25 (60%). In 'responsive' patients, serum total alkaline phosphatase was significantly reduced [from 579 +/- 645 U/l to 360 +/- 354 U/l (P less than 0.01) at 6 months, and to 273 +/- 311 U/l (P less than 0.01) at 12 months] and bone isoenzyme decreased similarly [from 482 +/- 608 U/l to 256 +/- 344 U/l (P less than 0.005), and to 225 +/- 354 U/l (P less than 0.01)]. The best results were in seven patients who had relapsed after subtotal parathyroidectomy. Declines in PTH of 30% or more were observed in four of seven patients at 1 month, in six of the seven (85%) at 6 months, and in all four patients seen after 12 months. The treatment corrected hypercalcaemia, making it possible to start or to increase daily vitamin D treatment. Side-effects were mild, rare, and transient.

Adult↗
PubMed1992

[Contrast media in echography].

In medical US, the use of specific contrast media to increase the echogenicity of structures and organs changes their absorption of the US beam, and modifies the through-transmission velocity. This can be of great diagnostic value. Contrast media can help depict vessels and cavities, increase the sensitivity of Doppler examination, and make the differentiation of normal and pathologic tissues easier. The products which are currently available do not completely fulfill the needs of clinical researchers. The first papers reporting on some clinical applications of these contrast media in humans are now appearing in literature. Contrast media for diagnostic US can be classified in five groups: 1) free gas bubbles; 2) stabilized gas bubbles; 3) colloidal suspensions; 4) emulsions; 5) aqueous solutions. These agents are quite different, as to both chemical and physical features and distribution within living tissues. Different clinical applications are thus possible for each of them; a unique contrast medium which will meet all the needs of the various clinical situations seems inconceivable at present. Most probably, a variety of products will develop, each with its own application field; in clinical practice, it seems likely that different products will be used, according to the specific clinical needs.

Blood Vessels↗
PubMed1992

[Color-Doppler instruments: their design principles and modes of use].

The use of color-Doppler US equipment allows the clinician to evaluate, at the same time and within the same image, both shape and structure of the examined organs and the flow patterns in the vessels within them. Such information as direction and velocity of blood flow are displayed with a variety of intravascular colors, according to a conventional code. Moreover, this diagnostic method can provide physiological and anatomical pieces of information in the same image and is therefore widely used in medical imaging. However, the images obtained by means of color-Doppler units are not always easy to understand and diagnostic misinterpretations may occur. In this paper we will summarize the physical and technological principles on which such units are based. In the first half of paper, the problems relative to acquisition and construction of the images are presented, together with the different technical approaches used to obtain flow velocity information. Moreover, the relationships between the "black-and-white" and the "color" parts of the images are described. The principles according to which color is assigned to vessels are reported, together with the patterns exhibited by a vessel according to the type of transducer used to examine it. The non-linear correlation between the color scale and flow velocities is also discussed. The second half of the paper deals with technical parameters of color-Doppler scanning, discussing the criteria of choice of transducers, the determination of Doppler angle, the setting of both wall filters and scanning depth. The problem of pulse repetition frequency (PRF) setting is also addressed; this parameter is especially critical in color-Doppler studies. The authors believe that careful setting of all examination parameters and the good knowledge of the physical and technological factors underlying color-Doppler images are the basis for a correct and useful approach to this fascinating technique.

Blood Vessels↗
PubMed1992

Ultrasonography of the neck.

The anatomic and pathologic involvement of the structures in the neck can be accurately studied with small parts ultrasonography. The thyroid and parathyroid glands and nodal chains are treated in this article; masses of the neck spaces are not considered because of their relative rarity.

Humans↗
PubMed1991

Lissencephaly in two brothers detected by US. A "pseudo-liver" pattern.

We report on two cases of lissencephaly in two brothers studied by high frequency ultrasound and subsequently confirmed by CT and, in one case, by post-mortem study. In addition to well known sonographic and CT signs described in the literature, a typical structural change of the brain (named "pseudo-liver") was detected using high-frequency sonography.

Brain↗
PubMed1989

Sonographic appearance of primary retroperitoneal cysts.

The sonographic findings observed in four patients with primary retroperitoneal cysts were reviewed. All lesions presented as fluid-filled masses with anechoic content and regular margins; all increased through transmission. Preoperative location of the cysts within the retroperitoneal space was possible in all cases by either real-time ultrasound (US) analysis of the different relationships of the kidneys and the cysts during respiratory movements or the anterior displacement of surrounding structures. A differential diagnosis among retroperitoneal lesions containing fluid is difficult and cannot be obtained with imaging methods alone. However, preoperative knowledge of both the retroperitoneal location of the disease process and its fluid content may help to narrow the diagnostic possibilities, thus allowing the surgeon to more accurately plan the therapeutic approach to the patient.

Adult↗
PubMed1987

240 hepatocellular carcinomas: ultrasound features, tumor size, cytologic and histologic patterns, serum alpha-fetoprotein and HBs Ag.

Two hundred and forty cases of hepatocellular carcinomas (HCC), diagnosed by ultrasonography and fine needle biopsy, were studied. The following parameters were investigated: 1. echo features (240 cases) - hypoechoic, 54; hyperechoic, 56; complex, 112; isoechoic with halo, 18; 2. tumor size (240 cases) - single tumor under 4.5 cm, 30; single tumor over 4.5 cm, 74; multiple masses or diffuse, 136; 3. cytologic pattern (240 cases) - well and medium differentiated, 144; pleomorphic, 43; poorly differentiated, 28; unclassified, 25; 4. histologic pattern (157 cases) - trabecular, 74; solid, 42; acinar, 1; mixed, 2; unclassified, 38; 5. alpha-fetoprotein (AFP) level (185 cases) - under 20 ng/ml, 79; between 20 and 320 ng/ml, 40; over 320 ng/ml, 66; 6. HBs Ag (208 cases) - present in 56 cases; 7. cirrhosis (102 cases) - present in 79 cases. Some of the above parameters were correlated with one another. There was: 1. a highly significant frequency of the hypoechoic feature among small HCC; 2. a percentage of AFP-producing tumors increasing with tumor size; 3. no relationship between AFP production and cytologic or histologic pattern; 4. no relationship between tumor size and cytologic or histologic pattern. However, among the small HCC, all the 9 HCC with a diameter of less than 3 cm showed a trabecular pattern and well-differentiated cells. Cirrhosis was present in every patient with a small HCC. Since the discovery of a small HCC is an incidental ultrasonographic finding in the context of severe liver disease, ultrasonographic monitoring of cirrhotic patients is the best available strategy to screen for small HCC.

Adult↗
PubMed1987

Normal anatomy and pathologic changes of the small bowel mesentery: US appearance.

The ultrasonographic (US) appearance of the normal small bowel mesenteric leaves was evaluated in two in vitro studies and in 30 patients. Such structures had an elongated shape, echogenic surfaces, and small vessels in their center and could be recognized in 28 of the 30 patients. They did not show active movements, and at their distal end, the small bowel loops could be seen and peristalsis detected. Doppler signals were obtained from the small vascular structures in their center in three additional cases. On the basis of these anatomic findings, pathologic changes such as lymphoma, desmoid tumor, metastatic lesions, dilated vessels, and edema could be detected in 15 patients. When examining with US patients with diseases prone to involve the mesentery, careful attention should be given to this structure, since useful information about the abdominal spread of the disease can be obtained.

Adult↗
PubMed1986

Percutaneous interstitial chemotherapy of a small hepatocellular carcinoma under ultrasound guidance.

A small (less than 3 cm) inoperable hepatocellular carcinoma was treated with percutaneous interstitial chemotherapy (PIC). 5-Fluorouracil was injected by a fine needle under ultrasound guidance. After 3 months a fine needle biopsy (FNB) yielded fibronecrotic material. After 18 months another FNB yielded steatosis and dysplastic cells and the lesion showed no increase in size. PIC could be an interesting alternative treatment for small tumors unresponsive to conventional therapies.

Administration, Cutaneous↗
PubMed1986

Fine-needle aspiration biopsy of bowel lesions under ultrasound guidance: indications and results.

Twenty-four patients with bowel lesions that could be imaged on a sonogram underwent ultrasound-guided fine-needle aspiration biopsy. Indications for biopsy included: poor condition of the patient precluding the use of barium studies and/or endoscopy (9 cases) or hindering technically adequate examinations (3); nonspecific radiographic images (6); inability to obtain an adequate biopsy sample during endoscopy (6). The results of biopsy were correct in the 18 cases proven by surgery or autopsy; in the remaining 6 patients, histologic results were considered conclusive, and were later confirmed by clinical, radiographic, and ultrasound follow-up. Fine-needle aspiration biopsy may be considered a simple, rapid, and accurate diagnostic procedure when an alternative approach to the study of gastrointestinal tract lesions is needed.

Adenocarcinoma↗
PubMed1986

The sonographic appearance of duodenal lesions.

The sonographic findings in 17 patients with duodenal tumors and in one patient with a benign ulcer and stricture of the duodenum were reviewed. An abdominal mass was detected sonographically in all patients; in 15 of 18 cases, such lesions presented high-level central echoes and hypoechoic periphery. Identification of the duodenal origin of the disease was possible by sonography in only 16 of 18 patients: by evaluation of the relationship of the mass with abdominal vessels in eight patients; by demonstrating that the lesion was continuous with a normal duodenum in seven patients; or by demonstrating the mass within the duodenum itself in one patient. Signs and symptoms of duodenal tumors are usually nonspecific, and sonography can be used as the first imaging method in these cases. A careful analysis of the relationship of the tumor to surrounding structures may allow correct identification of its origin.

Adenocarcinoma↗
PubMed1985

The thyroid gland with low uptake lesions: evaluation by ultrasound.

An ultrasound examination was performed in 401 patients who had isotopically cold, solitary lesions of the thyroid gland. Of the parameters studied, the level of echoes was the most useful in making the sonographic diagnosis: the rate of malignancy was extremely low both in hyperechoic and echo-free lesions. The presence of a peripheral, complete "halo" appeared to be helpful in differentiating benign lesions from malignant lesions. Approximately 20-25% of the lesions thought to be solitary on the radionuclide study were found to be multinodular on US. When fine-needle aspiration biopsy was used with US the need for surgical exploration of the thyroid gland was obviated in selected cases.

Adenocarcinoma↗