Hydrogastric sonography in the preoperative staging of gastric cancer

Basic practices for gastrointestinal ultrasound

The standard diagnostic modalities for gastrointestinal (GI) diseases have long been endoscopy and barium enema. Recently, trans-sectional imaging modalities, such as computed tomography and magnetic resonance imaging, have become increasingly utilized in daily practice. In transabdominal ultrasonography (US), the bowel sometimes interferes with the observation of abdominal organs. Additionally, the thin intestinal walls and internal gas can make structures difficult to identify. However, under optimal US equipment settings, with identification of the sonoanatomy and knowledge of the US findings of GI diseases, US can be used effectively to diagnose GI disorders. Thus, the efficacy of GIUS has been gradually recognized, and GIUS guidelines have been published by the World Federation for Ultrasound in Medicine and Biology and the European Federation of Societies for Ultrasound in Medicine and Biology. Following a systematic scanning method according to the sonoanatomy and precisely estimating the layered wall structures by employing color Doppler make diagnosing disease and evaluating the degree of inflammation possible. This review describes current GIUS practices from an equipment perspective, a procedure for systematic scanning, typical findings of the normal GI tract, and 10 diagnostic items in an attempt to help medical practitioners effectively perform GIUS and promote the use of GIUS globally.

Efficacy of hydrogastric sonography and spiral Computed Tomography in staging of gastric carcinoma--a comparative study

OBJECTIVE

Accurate preoperative diagnosis and staging of patients with gastric cancer is essential for optimal treatment. The standard of care for staging gastric carcinoma is helical CT. This study was conducted to compare the efficacy of hydrogastric sonography (HGS) with that of helical CT in the staging of patients with gastric carcinoma.

METHODS

A total of 42 consecutive patients (29 men and 13 women) diagnosed with gastric carcinoma after endoscopy and biopsy were staged on the basis of TNM classification, preoperatively with HGS and helical CT and postoperatively with histopathologic examination (HPE). The findings of HGS and helical CT were compared with those on HPE with respect to TNM stage.

RESULTS

Regarding T stage, the accuracy of HGS was 78.6% (kappa = 0.68) and that of helical CT was 66.7% (kappa = 0.48). In evaluating the nodal status, the accuracy of HGS was 66.7% (kappa = 0.52) and that of helical CT was 54.6% (kappa = 0.39). Regarding distant metastases, accuracy was the same with HGS and helical CT (accuracy 95.2%, kappa = 0.89).

CONCLUSIONS

When compared with HPE, HGS was found to be more accurate than helical CT for assessment of T and N staging. Sonographic and helical CT were equally accurate for the assessment of M stage.

Hydrosonography of the gastrointestinal tract

OBJECTIVE

Bowel sonography has become accepted as a useful tool in several gastrointestinal disorders. Filling of the gut with echo-poor liquids has been proposed to achieve a detailed evaluation of the bowel. This article refers to a review made concerning the benefits and limits of hydrosonography of the gastrointestinal tract.

CONCLUSION

The use of a luminal contrast agent in bowel sonography may improve results but should be adopted on a case-by-case basis, according to the clinical context and the experience of the sonologist.

Thickening of the gastric wall on transabdominal sonography: a sign of gastric cancer

PURPOSE

To determine the value of a thickened gastric wall detected during transabdominal sonography (TAS) in the diagnosis of gastric cancer.

METHOD

This prospective study comprised 312 patients who underwent both TAS and endoscopy. Transverse TAS scanning was performed using a 3.5-MHz curved transducer to measure gastric wall thickness in the antrum and body of the stomach. Based on endoscopic and histologic findings, we classified the patients into 3 groups: normal or benign disease (BD), early gastric cancer (EGC), and advanced gastric cancer (AGC). TAS findings were then compared.

RESULTS

The thickness of the gastric wall was 4.9 +/- 1.6 mm in 262 patients with BD, 5.6 +/- 2.4 mm in 21patients with EGC, and 10.3 +/- 4.7 mm in 29 patients with AGC (p < 0.01). A gastric wall thickness of greater than 7 mm had a 75.0% sensitivity, 92.6% specificity, 50.0% positive predictive value, and 97.4% negative predictive value in the diagnosis of AGC.

CONCLUSION

Although not suitable as a screening method for gastric cancer, a thickening of the gastric wall of >7 mm may be a marker for AGC.

Tumor estromal gástrico de riesgo intermedio: diagnóstico mediante ecografía hidrogástrica

Evaluation of submucosal lesions of the digestive tract with conventional endoscopy is unsatisfactory since this technique does not allow direct observation or correct evaluation of the size and layer of origin of the tumor; therefore, in most patients an etiological diagnosis cannot be established with this procedure. However, in most patients, endoscopic ultrasonography can resolve these problems: to a fair degree of certainty, this technique can differentiate malignant from benign lesions, measure their size, and establish their layer of origin. Endoscopic ultrasonography is the technique of choice to establish the presence and characteristics of submucosal tumors and their suitability for treatment. Moreover, this procedure can identify tumors that can be removed endoscopically without excessive risk. Hydrogastric ultrasonography can be an effective substitute for echoendoscopy when evaluating submucosal lesions and for staging tumors of the gastric antrum when echoendoscopy is not available or in patients in whom it cannot be performed. Hydrogastric ultrasonography is safe, inexpensive and very well tolerated by patients. We present the case of a female patient with a gastric GIST that was evaluated using hydrogastric ultrasonography. The size, layer of origin, and malignancy of the tumor were accurately established.