High-resolution Real-time Sonography Research Articles

Acute and perforated appendicitis: Current experience with ultrasound‐aided diagnosis

The clinical value of high-resolution real-time sonography for the diagnosis of acute and complicated appendicitis was prospectively investigated in 857 patients admitted with suspected appendicitis. The ultrasound findings were correlated with history and physical examination on admission. Sonography was able to make the diagnosis of appendicitis with a sensitivity of 89.7%, a specificity of 98.2%, an overall accuracy of 96.3%, and a positive and negative predictive value of 93.6% and 97%, respectively. Routine use of ultrasound before making therapeutic decisions has reduced the rate of unnecessary laparotomies from 20.3% to 11.3%. In 48 (24.7%) of 194 patients with proven appendicitis, the disease had progressed to perforation at laparotomy. History and clinical findings on admission classified 30 (62.5%) of these patients as "highly suspect;" however, 9 (18.8%) were classified as "equivocal" and 9 (18.8%) as "very unlikely." Only half (48%) of the patients with appendiceal rupture had white blood cell counts higher than 13,000/mm3 or fever above 38 degrees C (50%). Sonography enabled the visualization of the inflamed appendix and/or appendicular abscess in 44 (91.7%) patients with perforation. In 47 of 48 patients with appendiceal rupture, the ultrasound-aided diagnosis was made on hospital admission. Thus, the incidence of complicated appendicitis (24.7%) in our study population must be attributed to disease progression before admission and preclinical diagnostic delay.

Sonography versus palpation in the detection of regional lymph-node metastases in patients with malignant melanoma

High-resolution real-time sonography was done in 217 patients with malignant melanoma to compare its value in detecting regional lymph-node metastases with that of palpation. Lymph-node metastases were found in 29 patients by ultrasound whereas, by palpation, metastases were detected in 15 patients only. The presence of metastases was proven by histopathology after surgical lymphadenectomy in these ultrasound positive cases. Thus sonography was superior to palpation, and in addition permitted distinction between metastatic changes and inflammatory lymph-node enlargement. Ultrasound is recommended for preoperative staging as well as in postoperative monitoring of patients with malignant melanoma.

Sonographically guided arthrocentesis of the hip.

High-resolution real-time sonography not only provides a noninvasive means of diagnosing hip effusions, but also provides easy access for arthrocentesis. Nineteen sonographically guided hip arthrocentesis were performed in 18 patients. In 13 of 19 patients aspirated, capsular distension was present. In 10 of 19 patients, fluid could be aspirated from the joint space (volume varying from 1 to 9 mL). Saline lavage was performed in 12 of the 19 joints needled. Intra-articular location was confirmed by observation during distension on real-time images or by successful aspiration. Sonographically guided arthrocentesis has potential advantages over conventional fluoroscopic techniques. These include a lack of ionizing radiation, superior visualization of needle location within the joint capsule, and the ability to diagnose soft tissue and periarticular abnormalities generally not seen fluoroscopically.

Simple Cyst of the Testis

We report 5 cases of simple cyst of the testis, the largest series to date, and review the literature. Included are 2 autopsy cases, a case of a multilocular simple cyst and 1 case treated nonoperatively. Based on our experience, simple cyst of the testis should be suspected particularly in an enlarged but otherwise palpably normal testis. High resolution real-time scrotal sonography revealing an anechoic mass in the testis with well defined walls, and enhanced posterior through transmission and edge shadowing is diagnostic for a simple cyst. An asymptomatic simple cyst of the testis may be treated with observation alone. The symptomatic simple cyst should be treated ideally with local parenchyma-sparing excision.

The use of preoperative localization of adenomas of the parathyroid glands by thallium technetium subtraction scintigraphy, high-resolution ultrasonography, and computed tomography : Roses DF, Sudarsky LA, Sanger J, et al. (New York University Medical Center, 530 First Avenue, New York, NY 10016, U.S.A.) Surg Gynecol Obstet 1989;168:99–106

Thirty-six patients with primary hyperparathyroidism were studied preoperatively by thallium-201 and technetium-99m pertechnetate subtraction (Tl-201/Tc-99m) scintigraphy, high-resolution real time ultrasonography and computed tomographic (CT) scanning. None of the patients had had previous surgical treatment of the parathyroid or thyroid glands. All of the patients underwent systematic bilateral exploration of the neck. All of the patients were successfully explored and 41 abnormal parathyroid glands were identified. Five patients had two adenomas. In six instances, adenomas were identified in ectopic anatomic sites. The sensitivity of correctly localizing the abnormal glands with these techniques was 49 per cent for the Tl-201/Tc-99m scintigraphy, 34 per cent for ultrasonography and 41 per cent for CT scanning. The Tl-201/Tc-99m scintigrams detected two of the six ectopically located adenomas, CT detected one, while ultrasound detected none. The five patients with multiple adenomas were not accurately identified as having multiple gland enlargement by any of these studies. Therefore, preoperative localization studies with these three techniques did not provide reliable information for initial bilateral exploration of the neck.

Detection of muscle, vein and artery infiltrations of cervical lymphatic metastases

In a prospective study, 15 patients with squamous cell carcinomas of head and neck and clinical fixed cervical lymph node metastases were examined to determine the value of computed tomography, magnetic resonance imaging and high resolution real time ultrasonography in preoperative recognition of muscle and vessel infiltration. The preoperative findings were compared with the microscopic results of neck specimens and the operative reports. For each diagnostic method sensitivity, specificity, and effectivity were calculated. Ultrasonography, magnetic resonance imaging and computed tomography can assess muscle infiltrations as well. Metastatic infiltrations of carotid arteries are best recognised by ultrasonography and magnetic resonance imaging. Both methods are more valuable than computed tomography. All methods are unsuccessful in detecting infiltrations of the jugular vein. In conclusion, metastatic infiltrations of surrounding tissue, as described by imaging methods, are rarely confirmed by histological results.

High-resolution Real-time Sonography in the Evaluation of Carotid Atherosclerosis

High-resolution real-time sonography (HRS) is usually performed in patients with occlusive cerebrovascular disease. Unfortunately, there is no standard imaging technique for carotid imaging. In this report, an imaging technique for detecting carotid plaques is introduced. At first, to get the most suitable image of the carotid bifurcation in the longitudinal projection, examination was carried out with a 7.5 MHz probe. The probe should maintain constant movement with the same slow speed to detect details of the plaque. The ultrasonic images were recorded with a video tape recorder simultaneously. After that, the most suitable multiple consecutive planes (5 to 7 planes) were re-photographed. Postoperatively, the detailed ultrasonographic images were reviewed and compared with the patho-morphological findings of the planes. A 57-year-old patient with an episode of amaurosis fugax was reported. He had ulcerated and calcified plaques in the left cervical carotid artery. The postoperative macro- and microscopic findings showed good correlations to the display of images at the preoperative ultrasonic examinations. The echo-density of all atheromatous plaques except for those accompanied by calcification, was lower than that of the normal media. It was very difficult to distinguish a true ulceration from a necrosis (or a bleeding space) in the arterial wall. In this case the detailed and consecutive display of the high-resolution B-mode scan was a very useful method to identify a fine structure of atheromatous plaques of the arterial wall in the cervical carotid artery.

Indium-111-labeled platelet scintigraphy in carotid atherosclerosis.

We evaluated platelet accumulation in carotid arteries by means of a dual-radiotracer method, using indium-111-labeled platelets and technetium-99m-labeled human serum albumin, in 123 patients (92 men, 31 women; median age 60 years). Sixty patients had symptoms of transient ischemic carotid artery disease, and 63 patients with peripheral arterial occlusive disease served as controls. Antiplatelet treatment with acetylsalicylic acid was taken by 53 of the 123 patients. In 36 of the 60 symptomatic patients, platelet scintigraphy was repeated 3-4 days after carotid endarterectomy. Comparison of different scintigraphic parameters (platelet accumulation index and percent of the injected dose of labeled platelets at the carotid bifurcation) showed no significant differences between symptomatic and asymptomatic patients, and the severity of stenosis and the presence of plaque ulceration also had no influence on the parameters. There was no difference between patients with a short (less than 4 weeks) or long (greater than 4 weeks) interval from the last transient ischemic attack to scintigraphy and no difference between patients with or without antiplatelet treatment. Classifying the patients according to plaque morphology judged by high-resolution real-time ultrasonography also demonstrated no differences. No significant correlation was found between any scintigraphic parameter and other platelet function parameters such as platelet survival time, platelet turnover rate, and concentration of platelet-specific proteins. Quantification of platelet deposition after carotid endarterectomy in 36 patients demonstrated a significant increase of the median platelet accumulation index and the percent injected dose index. There were no significant differences between patients receiving high-dose (1.0 g/day) or low-dose (1.0 g/day) acetylsalicylic acid in scintigraphic results.(ABSTRACT TRUNCATED AT 250 WORDS)

High resolution real time sonography in sports specific muscle injuries. Sonomorphologic-anatomic correlation and diagnostic criteria

In 250 examinations of 86 patients, high resolution real time sonography with a 7.5 MHz linear transducer proved to be a readily available, low-cost and significantly relevant imaging method in diagnosis and follow-up of muscular lesions in sportsmen. The method offers a high measure of safety in excluding rupture or in enabling differential diagnosis between partial muscular rupture and muscular spasm, so that the choice of treatment can be decisively influenced by sonography. Hence, rapid rehabilitation, which is so essential in competitive sport, is speeded up even further. In extensive ruptures or rupture haematoma, therapeutic ultrasound-guided puncture can be performed or indication for surgery can be facilitated in subtotal or complete tears of a muscle that is important for high-level performance.

Peripheral nerves of the extremities: imaging with US.

High-resolution real-time ultrasonography (US) was used to evaluate peripheral nerves of the extremities in healthy subjects and in 11 patients with a mass developed from a peripheral nerve. The normal median and ulnar nerves in the upper extremity and the normal sciatic and external popliteal nerves in the lower extremity were seen, all having an echogenic fibrillar echotexture. Pathologic findings included nine cases of benign tumor (four schwannomas, three neurofibromas, two traumatic neuromas), one of neurilemmitis, and one of tuberculoid leprosy. All lesions were hypoechoic. Three of the four schwannomas had well-defined contours, and two were associated with a typical distal sound enhancement. Neurofibromas and traumatic neuromas were less sharply delineated. Inflammatory conditions were characterized by a hypoechoic, thickened nerve. US was effective in imaging nerve masses in the extremities, and large normal nerves can now be demonstrated with high-resolution US.

Sonographic evaluation of the rotator cuff: Correlation with arthroscopy

High-resolution real-time sonography has been reported as a non-invasive means of evaluating the integrity of the rotator cuff. Fifty-two patients underwent both sonographic and arthroscopic evaluation of the rotator cuff. There were 42 men and 10 women with an average age of 47 years (range 28-71 years). The duration of shoulder pain averaged 24 months (range 3 months to 9 years). Thirty-five rotator cuff tears were noted arthroscopically. Twenty-seven of the tears were diagnosed by sonography for a sensitivity rate of 77%. Eleven of the 17 intact rotator cuffs were normal by sonography for a specificity rate 65%. The overall accuracy of sonography was 73% and the predictive value of a positive sonogram was 82%. Sonography appears to be a good initial screening examination in evaluating the integrity of the rotator cuff. It is noninvasive and relatively inexpensive. Technical limitations of this technique as well as the experience of the radiologist in performing and interpreting the examination play a major role in the accuracy of this test. As instrumentation improves and as experience in using this technique increases, we expect the accuracy of sonography in detecting tears of the rotator cuff to continue to improve.

High-resolution real-time ultrasonography: A new tool in the diagnosis of acute appendicitis

A prospective study was performed to assess the sensitivity and specificity of ultrasonographic evaluation in 44 patients with suspected appendicitis. We found ultrasonographic evaluation to have a sensitivity rate of 89 percent, a specificity rate of 86 percent, and an overall accuracy rate of 87 percent. These results are very similar to those in other recently reported studies. We also identified certain patients in whom nondiagnostic studies are likely. Our results suggest that ultrasonographic evaluation may be of particular use in selected patients who do not demonstrate the classical signs and symptoms of acute appendicitis.

Sonographic diagnosis of subclavian and internal jugular vein thrombosis.

Seven patients with internal jugular and/or subclavian vein thrombosis were studied with real-time sonography and venography. High-resolution real-time sonography was used to tabulate morphologic parameters (venous size, shape, intraluminal echoes, and presence of collateral veins), as well as physiologic parameters (mobile venous valves, distention, compressibility, pulsation). Chronic venous thrombosis was characterized by the presence of collateral veins, spread of the thrombus to other major veins, and loss of normal vascular landmarks with poor visualization of the actual thrombus, the "cut-off sign." Acute catheter-induced thrombosis was confined to one vessel, and the thrombus was seen clearly in all cases. Two new signs of thrombosis, the absence of the beating venous valve and the "cut-off sign," are particularly useful in the sonographic diagnosis of internal jugular vein thrombosis.

Testicular tumors: prospective analysis of real-time US patterns and abdominal staging.

Echomorphologic features of 57 testicular lesions (48 neoplasms, nine benign lesions) were analyzed prospectively by means of high-resolution real-time ultrasonography (US). There was a broad spectrum of texture patterns for testicular malignancies, 92% of which exhibited a predominantly decreased echogenicity compared with that of normal tissue. US findings alone could not be used to make a specific prediction of malignant disease or to classify a neoplasm histologically. However, different kinds of tumors exhibited characteristic echomorphologic features that corresponded to their gross morphologic appearance; a knowledge of these echomorphologic features is extremely useful for the US differentiation of tumors from nonneoplastic scrotal pathologic conditions. All neoplasms in this series displayed distinct abnormalities in parenchymal texture, and all were detected with US. The sensitivity and predictive value of a normal sonogram were as high as 100%. With regard to the detection of retroperitoneal lymph node metastases from testicular tumors, abdominal US had an overall accuracy rate of 96% and was of superior diagnostic value compared with bipedal lymphangiography.

Histologisch kontrollierter Vergleich von Palpation und Sonographie bei der Diagnose von Halslymphknotenmetastasen*

During a period of 2 1/2 years palpation and high-resolution real-time sonography were carried out in 83 non-selected patients with head and neck carcinomas to diagnose metastatic involvement of cervical lymph nodes. The findings were compared with the results of the microscopic examination of the lymph nodes from the neck dissection specimen. Sonography is characterized by a high sensitivity in the detection of lymph node metastases. The relatively low specificity of this method proves that many enlarged but not metastatically involved lymph nodes are also displayed by ultrasound. Although there are no specific echomorphological criteria permitting a reliable identification of lymph node metastases, their sonographic visibility cannot be determined only by the size of the lymph node. Lymph node metastases less than 1.5 cm in diameter, in particular, can be detected more often by ultrasound than by palpation. Therefore, it can be presumed that pathological transformations besides the reactive hyperplasia occurring during metastatic involvement will also influence the echographic representation of lymph nodes. The accuracy data of other methods used for detecting lymph node metastases (computed tomography and lymphoscintigraphy) were compiled from the literature and compared with those of palpation in more than 5000 patients. Basing on our experiences with sonography in this field we tried to assess the chances and limitations of ultrasound in the pretherapeutic diagnosis of cervical lymph node metastases.

Acute appendicitis: high-resolution real-time US findings.

High-resolution, real-time ultrasonography (US) with graded compression was used to evaluate 90 patients with clinically suspected acute appendicitis. US visualization of a noncompressible appendix was the primary criterion for a diagnosis of acute appendicitis. The overall sensitivity was 89%, the specificity was 95%, and the accuracy was 93%. When the results in women were analyzed separately (n = 49), the overall accuracy was 96%. Several important limitations of US scanning were encountered. There were three false-positive examinations in patients with a sonographically visible appendix whose symptoms spontaneously resolved. Another patient had a normal compressible appendix with a thin (2-mm), symmetric wall surrounded by ascites. There were three nondiagnostic studies (3%) due to inability to compress the cecum and right lower quadrant adequately because of exquisite tenderness (two patients) or massive ascites (one patient). When interpreted in light of the clinical examination, sonography should significantly reduce the rate of false-negative appendectomies, particularly in women.

Safe jugular and subclavian venipuncture under ultrasonographic guidance

Although jugular and subclavian venipuncture is a valuable technique and frequently utilized, blind venipuncture is at times associated with complications such as arterial puncture, pneumothorax, and malpositioning of catheters. We performed venipuncture under the guidance of high-resolution real-time ultrasonography, and these catheter-related complications were prevented. Jugular, subclavian and innominate veins and arteries, the pleura, and the lung are all delineated by supraclavicular and subclavicular scanning, and the needle and catheter can also be visualized. Ultrasonographically-assisted jugular and subclavian venipuncture is a simple and helpful procedure to carry out safe venipuncture. This method is particularly recommended for less experienced physicians and for more accurate puncture in patients with distorted cervical or subclavicular anatomic characteristics.

Hepatic cavernous hemangioma: diagnosis with 99mTc-labeled red cells and single-photon emission CT.

During the performance of high-resolution real-time abdominal sonography, small echogenic hepatic masses are frequently discovered. A second imaging test to confirm the suspected diagnosis of hemangioma is often required. Planar labeled red-cell imaging will often not detect hemangiomas smaller than 3 cm. We studied 14 patients with labeled red-cell scintigraphy and single-photon emission CT (SPECT). Six hemangiomas were diagnosed by SPECT that would have been missed by planar imaging alone. All six were smaller than 2.5 cm. With the addition of SPECT, labeled red-cell scintigraphy has specificity and sensitivity that make it at least as reliable as dynamic CT for the noninvasive diagnosis of hepatic cavernous hemangioma.

Fine-needle biopsy of parathyroid adenomas.

High-resolution real-time sonography was performed in 15 cases of clinically and chemically suspected primary hyperparathyroidism and in 20 patients with different thyroid nodules. The suspected enlarged parathyroid glands and the thyroid nodules were percutaneously punctured under sonographic control. Concentrations of parathyroid hormone, human thyroglobulin, and human calcitonin were measured in the aspirate, and immunocytology was performed. The mean concentration of the aspirated parathyroid hormone in the parathyroid glands was 4,013.6 pmol/l +/- 4,519 (SD) as compared with 14.9 pmol/l +/- 8.7 in the thyroid nodules. Thyroglobulin was present in the aspirated fluid of parathyroid adenomas located behind the thyroid (mean +/- SD, 398.1 ng/ml +/- 317). In comparison, the aspirated thyroglobulin from the thyroid nodules averaged 9,689.7 ng/ml +/- 3,732. Immunocytology for parathyroid hormone was positive in 14 of the 15 biopsied specimens. Of 15 patients who were scanned for suspected hyperparathyroidism, six had concomitant thyroid nodules. It is concluded that the measurement of high concentrations of parathyroid hormone in the aspirate from a cervical mass, with sonographic control of needle position and/or positive immunocytology provides absolute localization of parathyroid tissue.

Real-time sonography in the diagnosis of neck cysts

The diagnostic possibility of high resolution real time sonography has been investigated in 31 patients with cysts in the neck. The method is of special value preoperatively by demonstrating neighbouring structures, such as the parotid and thyroid glands and the major vessels in the neck; it contributes to differential diagnosis and surgical planning. Lateral cysts, because of their contents, may be highly echogenic and may be difficult to distinguish from lymphomas. The differential diagnosis of various cysts in the neck is discussed. An important aspect of sonography of the neck is the experience of the operator and his detailed knowledge of the local anatomy.