Endoscopic ultrasonography (EUS) combines the advantages of conventional endoscopy with the capabilities of ultrasonography. EUS allows clinicians to see through the wall of the gastrointestinal tract. The close proximity allows the use of relatively high frequencies with the resulting increase in tissue contrast and resolution. Despite some limitations, this new modality does open new horizons in the diagnosis and characterization of upper gastrointestinal diseases.

The evaluation of large gastric folds poses a difficult diagnostic problem. Exploratory laparotomy with full-thickness gastric biopsy is frequently required in order to rule out malignancy. To examine the utility of endoscopic ultrasonography in the diagnostic evaluation of large gastric folds, 28 consecutive patients with endoscopically or radiographically diagnosed large gastric folds were studied; in most of these patients endoscopic biopsies had been inconclusive for malignancy. Sixteen subjects were women and 12 were men, with a mean age of 57 years (range, 23 to 84). All patients underwent endoscopic ultrasonography to determine the anatomic wall layer of enlargement; large-forceps biopsy with histopathologic review was then performed when appropriate. Endoscopic ultrasonography demonstrated enlargement of layer 2 only (deep mucosa) in 64% (18/28) of patients, primarily of layer 3 (submucosa) in 14% (4/28), and of layer 4 (muscularis propria) in 21% (6/28). Large-forceps endoscopic biopsy performed immediately after ultrasonography in 86% (24/28) revealed acute or chronic inflammation in 67% (16/24), malignancy in 16% (4/24), and Ménétrier's disease in 4% (1/24). The biopsy results of 3 patients (13%) were negative for malignancy, but because of ultrasonographic findings of wall thickening involving layers 3 and 4 (submucosa and muscularis propria), they underwent laparotomy, which revealed primary gastric adenocarcinoma. Endoscopic ultrasonography demonstrated gastric varices in 4 patients; biopsy specimens were not taken. One patient with gastric lymphoma had only a layer 2 abnormality, but the correct diagnosis was made by endoscopic biopsy. Malignancy did not develop in any of the patients with gastric wall thickening limited to layer 2 and negative biopsy results during a mean follow-up period of 35 months.(ABSTRACT TRUNCATED AT 250 WORDS)

PURPOSE Endoscopic ultrasonography (EUS) has been shown to determine accurately the depth of invasion of the stomach wall in gastric carcinoma. We undertook this study to determine if T (tumor) stage as determined by EUS correlated with recurrence after resection and could be used to identify patients preoperatively at high risk for recurrence. MATERIALS AND METHODS We reviewed the surgical pathology and obtained follow-up data from the first 50 patients who underwent preoperative EUS for staging of gastric carcinoma. Rotating sector-scan ultrasound endoscopes were used with switchable frequencies of 7.5 MHz and 12 MHz. RESULTS Of 50 patients, 43 underwent resection with curative intent and were available for follow-up. The concordance of EUS T stage with pathologic T stage in these patients was 86%. At a median follow-up duration of 25 months, only two of 13 patients with preoperative EUS stage T1 or T2 disease were found to have recurrence, while 23 of 30 patients with EUS stage T3 or T4 disease had recurrence (P = .0002) and 22 died. CONCLUSION We conclude that patients with a preoperative EUS stage T1 or T2 are at low risk for postoperative recurrence, while patients with EUS stage T3 or T4 are at high risk for early postoperative recurrence. The latter patients are reasonable candidates for controlled trials of alternative preoperative management programs, such as chemotherapy, in an effort to improve their poor prognosis.

Background. After a pancreatic endocrine tumor has been diagnosed on the basis of clinical signs and the results of laboratory tests, localization of the tumor by the usual imaging procedures fails in as many as 40 to 60 percent of patients. Endoscopic ultrasonography, a sensitive test for small carcinomas of the pancreas, might also be useful in patients with endocrine tumors of the pancreas that cannot be localized by conventional methods.Methods. We studied 37 patients later shown to have 39 endocrine tumors of the pancreas who had negative results on transabdominal ultrasonography and CT. All the patients underwent endoscopic ultrasonography, and 22 also underwent selective angiography. All the tumors were confirmed by surgical excision and immunohistologic examination; they consisted of 31 insulinomas, 7 gastrinomas, and 1 glucagonoma, 0.5 to 2.5 cm (mean, 1.4 cm) in diameter. All but one of the patients were cured of their disease, as ascertained by at least six months of clinical and laboratory follow-up.Results. Using endoscopic ultrasonography, we were able to localize 32 of the 39 tumors (sensitivity, 82 percent); no tumor was incorrectly localized. The size of the tumors was very similar (within 2 mm) to that predicted by endoscopic ultrasonography. Among the 22 patients who underwent both angiography and endoscopic ultrasonography, ultrasonography was significantly more sensitive than angiography for tumor localization (sensitivity, 82 percent vs. 27 percent). Among 19 control patients without pancreatic endocrine tumors, endoscopic ultrasonography was negative in 18 (specificity, 95 percent).Conclusions. Endoscopic ultrasonography is a highly sensitive and specific procedure for the localization of pancreatic endocrine tumors. It should be considered for the preoperative localization of such tumors once the clinical and laboratory diagnosis has been established.

Endoscopic ultrasonography combines the advantages of conventional endoscopy with the capabilities of ultrasonography. This permits the examiner to see through the wall of the gastrointestinal tract. The close proximity permits the use of relatively high frequencies, with the resulting increase in tissue contrast and resolution. There are limitations to its use, however, with the main one being a field of view limited to a 7-cm radius. Discussed in this article is its use for the gastrointestinal wall, the esophagus, the stomach, the duodenum, and the pancreas.

The proper diagnosis of submucosal upper gastrointestinal tract mass lesions by endoscopy or barium study is difficult. Differentiation between submucosal tumors, vascular structures, and extrinsic organs is often impossible. We performed endoscopic ultrasound examination of 91 patients with upper gastrointestinal submucosal mass lesions. Endoscopic ultrasound was accurate in determining the site of origin in 48 of 50 cases where pathology or angiography comparison was available. Leiomyoma, lipoma, varices, and carcinoma had characteristic ultrasonographic findings. Endoscopic ultrasound is a useful procedure in the evaluation of upper gastrointestinal submucosal mass lesions.

Fifty patients with esophageal cancer proved by means of biopsy underwent preoperative staging with endoscopic ultrasonography (US); in 42 of the patients, dynamic CT of the chest and abdomen was also performed. All results were compared with the findings at pathologic examination of resected specimens. In staging the depth of tumor growth, endoscopic US was significantly more accurate (46 of 50 tumors [92%]) than CT (25 of 42 tumors [60%]) (P less than .0003). In staging regional lymph nodes, it was more accurate (44 of 50 patients [88%]) than CT (31 of 42 patients [74%]), but this was not statistically significant. In staging distant metastases, however, CT was more accurate (38 of 42 patients [90%]) than endoscopic US (35 of 50 patients [70%]) (P less than .016). The highest concordance with surgical and pathologic findings in overall stage (36 of 42 tumors [86%]) occurred with the combined use of CT and endoscopic US, which was significantly more accurate than use of CT alone (27 of 42 tumors [64%]) (P less than .008).

Endoscopic sonography was used to examine the upper gastrointestinal tract of 550 patients referred for evaluation of abnormal findings seen on conventional endoscopy, upper gastrointestinal series, and CT. This essay illustrates the potential uses and limitations of this technique. Special emphasis has been given to the use of landmarks to facilitate orientation of the transducer in both the esophagus and stomach. Specific examples demonstrate involvement of individual layers of the bowel wall in both benign and malignant processes. It is stressed that this is a combined procedure requiring both an endoscopist and a radiologist. Endoscopic sonography is a valuable new technology with substantial potential in the evaluation of the upper gastrointestinal tract.

High-frequency endoscopic ultrasonography (EUS) was used to image the pancreas through the wall of the stomach and duodenum in 12 patients with clinically suspected pancreatic endocrine tumors. In another patient, endocrine tumors in the wall of the duodenum were imaged by EUS. The findings were compared with those obtained by dynamic computed tomography (all patients) and selective angiography (eight patients). Laparotomy was done in eight patients. In our 13 patients, EUS detected endocrine tumors of the pancreas and duodenum in ten patients. More than one tumor was evident in five patients, including one of two patients with multiple endocrine neoplasia syndrome type I. In the eight patients treated surgically, there was one false-positive finding as a result of hypertrophic peripancreatic lymph nodes and one false-negative finding, in retrospect obviously imaged but incorrectly interpreted. The technique of EUS imaged small tumors in the pancreas (0.5 to 2.0 cm in diameter) in five patients where dynamic computed tomography and selective angiography were negative, but surgery and pathologic examination confirmed the EUS findings. This technique appears to be an important new addition to the battery of tests used for preoperative localization of endocrine tumors of the pancreas.

Fifty consecutive patients with gastric adenocarcinoma proved by means of biopsy underwent preoperative staging with endoscopic ultrasonography (US). Dynamic computed tomography (CT) of the chest and abdomen was performed before surgery in 33 of the patients. In all 50 patients, the TNM classification of the American Joint Committee on Cancer was used to compare the imaging findings with pathologic findings in specimens resected at surgery. When the depth of tumor penetration was evaluated, the findings at endoscopic US and those at pathologic examination were concordant in 46 of 50 patients (92%), and the findings at dynamic CT and those at pathologic examination, in 14 of 33 patients (42%) (P < .00042). Evaluation of regional lymph node metastases showed a concordance of 78% with endoscopic US and 48% with dynamic CT (P < .038). Overall determination of stage with both dynamic CT and endoscopic US showed a concordance of 73%, compared with a concordance of 45% for dynamic CT alone (P < .028).

Gastric mucus and air bubbles are frequent sources of artifacts during endoscopic ultrasonography (EUS). To reduce these artifacts, we prepared a mucolytic-antifoam solution consisting of simethicone, acetylcysteine, and sodium bicarbonate and performed a prospective randomized and controlled trial comparing this solution (21 patients) to a placebo (22 patients) during EUS. Eight patients in the drug group received a perfect score for both mucolytic and antifoam effect compared with none in the placebo group (p < 0.001). For overall rating, the drug group received a total of 10 excellents and 9 goods compared with 9 goods, 10 satisfactories, and 1 unacceptable in the placebo group (p < 0.001). There were no complications associated with the solution. In conclusion, a mucolytic-antifoam solution improved endoscopic visualization and reduced artifacts during EUS study. Its routine use during EUS procedures is therefore recommended.

Endoscopic ultrasonography (EUS) with a 7.5 MHz transducer was used to examine the upper gastrointestinal tract in 40 patients who had resection of esophageal or gastric cancer, and symptoms suggesting recurrence. There were 24 patients with recurrent cancer in the area of the surgical anastomosis (based on endoscopic biopsy in 16, repeat endoscopy in 2, and surgery after negative endoscopy in 6), and 16 patients without anastomotic recurrence. With EUS, locally recurrent cancer was correctly identified by nodular hypoechoic thickening at the anastomosis in 23 of 24 patients with one false negative; absence of anastomotic recurrence was correctly diagnosed in 13 of 16 with three false positives (sensitivity, 95%; specificity, 80%; positive predictive accuracy, 88%; and negative predictive accuracy, 92%). High frequency EUS with limited depth of penetration is not effective for evaluation of distant metastases, but is ideally suited for diagnosis of locally recurrent esophageal and gastric cancer.

Ten years after right hepatic lobectomy for primary hepatocellular cancer, a 45-yr-old black woman presented with bleeding esophageal varices. After five endoscopic injection sclerotherapy procedures using sodium morrhuate, she developed fever and elevated white blood count. Reendoscopy, chest x-ray, and upper gastrointestinal contrast x-rays showed no local complication. Urine analysis was normal, but CT scans, renal sonograms, and white blood cell radionuclide scan demonstrated bilateral perinephric abscesses. Percutaneous abscess drainage grew Streptococcus pneumoniae, normally found in the nasopharyngeal flora, which was probably a result of hematogenous spread. The perinephric abscesses were successfully treated with percutaneous drainage and antibiotics. Renal infection should be considered as a possible locus of distant blood-borne infection in patients who develop fever after endoscopic injection sclerotherapy.