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.

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.

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.

High-resolution sonography of the recurrent laryngeal nerve: anatomic and pathologic considerations.

During sonographic examination of the neck using high-resolution small-parts equipment, the minor neurovascular bundle may be identified in virtually all patients. Postmortem studies in three cadavers demonstrated that this structure is actually the recurrent laryngeal nerve (RLN). Furthermore, findings observed during sonographic examinations of the neck in nine patients with RLN paralysis of unknown origin were reviewed. Compression, displacement, or infiltration of the nerve from thyroid (seven cases) or parathyroid (two cases) nodules were noted, and this allowed the site and cause of the paralysis to be identified.

Percutaneous ethanol injection of parathyroid tumors under US guidance: treatment for secondary hyperparathyroidism.

In 12 patients with secondary hyperparathyroidism, 13 parathyroid tumors detected with the use of sonography and confirmed by fine-needle aspiration biopsy were treated by percutaneous injection of absolute ethanol under ultrasonographic guidance. Indications for this procedure were recurrence of parathyroid tumors after previous subtotal surgery, high surgical risk, or refusal of surgery. Significant volume reductions were recorded for the larger glands; in the smaller ones, structural changes were observed as well. Clinical and biochemical therapeutic effects were obtained in most cases of single hyperplastic glands treated. Percutaneous alcoholic ablation of enlarged parathyroid glands can be used in cases of secondary hyperparathyroidism when surgery is contraindicated or problematic; it can also improve responsiveness to medical therapy, delaying the need for surgery.

Fine-needle biopsy of hepatic hemangioma with sonographic guidance.

Thirty-three focal hepatic lesions later proven to be hemangiomas underwent sonographically guided fine-needle aspiration biopsy. Indications for cytologic assessment were an atypical sonographic pattern in 11 cases, the need to differentiate from liver metastases in 12 patients with a history of neoplasm, and other indications in 10. The aspirated material consisted of blood alone in 24 cases; in the other nine cases, endothelial cells and/or agglomerates of capillaries were demonstrated also, and this was considered to be diagnostic. In one case, intratumoral bleeding was demonstrated sonographically, but no treatment was needed. The possible angiomatous nature of an hepatic lesion should not be considered an absolute contraindication to biopsy, provided that a fine needle is used and the optimal route to the lesion is chosen.

Sonographically guided fine-needle aspiration biopsy of adrenal masses.

Percutaneous fine-needle aspiration biopsy of solid adrenal masses was performed under real-time sonographic guidance in 18 patients. Cellular material was aspirated in all cases. Cytologic examinations were correct in 11 metastatic deposits, three primary adrenal adenocarcinomas, and one pheochromocytoma. One subsequently proven primary adenocarcinoma was not diagnosed. In two cases of adenoma, normal adrenal cells were aspirated. Percutaneous aspiration of adrenal masses is recommended when the precise nature of the lesions is clinically required. The simplicity and speed of fine-needle aspiration biopsy under sonographic control and its high diagnostic accuracy and safety suggest its use as a routine procedure in the management of patients with adrenal masses well depicted by sonography.

Intussusception of the bowel: a new sonographic pattern.

The ultrasonic findings in a case of small bowel intussusception in an adult patient are presented. The sonographic features vary with the scanning plane. Scans along the longitudinal axis of the involved segment show a diagnostic pattern, not previously described: three parallel stripes of low echogenicity delineating two reflective areas.