Law et al.11 performed ultrasonography in 22 patients with a diagnosis of recurrent perianal sepsis or fistula in ano. Internal openings were defined as breaks in the mucosal layer. Fistula tracts created hypoechoic bands within the intersphincteric plane and usually communicated with a cavity or scar that appeared as hypoechoic areas. Hypoechoic defects within the EAS were interpreted as transsphincteric fistula tracts. All sonographic data were prospectively collected, and compared with surgical findings. Ultrasonography correctly identified the internal opening in 8 of 12 patients, the primary tract in 11 of 12 patients, a superficial abscess in 2 of 3 patients, and an intersphincteric abscess in 10 of 12 patients. The ultrasound, however, failed to identify an infralevator abscess in three patients and a supralevator abscess in two patients.

Cho12 defined the endosonographic criteria for an internal opening. He identified three criteria: intersphincteric tract, internal sphincter defect, and subepithelial breach.

The combination of all three findings yielded a 94% sensitivity, 87% specificity, 81% positive predictive value, and a 96% negative predictive value.

Choen et al.13 performed a prospective trial comparing the accuracy of digital examination and anal ultrasonog-raphy in defining the anatomy of the fistula. They discovered no statistical difference between the consultant or research fellow's digital assessment and ultrasonography in identifying intersphincteric and transsphincteric tracts. These investigators found ultrasonography to be of no help in identifying suprasphincteric and extrasphincteric tracts compared with the clinical examination, which was accurate in 78% of these cases. These authors therefore believed that ultrasonography had limitations in the evaluation of the complex fistula.

Yang et al.14 reported our initial experience with anal ultrasonography for anal fistulas. Sonographic data were compared with surgical findings in 11 patients with fistulas and 6 patients with a suspicion of abscess. In 82% of the patients, sonographic findings correlated with the operative findings. In one patient, a horseshoe fistula was incorrectly assessed as a lateral transsphincteric fistula, and in another patient with Crohn's disease, the primary tract was not visualized. We have since used hydrogen peroxide injection of the tract as an image-enhancement technique during anal ultrasonography for complex and recurrent fistulas.15 Fistula tracts typically have a hypoe-choic appearance. With the injection of hydrogen peroxide, the tract becomes hyperechoic as a result of the bubble-induced increased echogenicity. We believe this technique has helped us to identify tracts more easily. Poen et al.16 also have found hydrogen peroxide injection to be useful in delineating the anatomic course of perianal fistulas. In a study of 86 patients, endoanal ultrasound was able to identify 74 anal fistulas (43 transsphincteric, 11 intersphincteric, 6 suprasphincteric, 3 superficial, and 11 anovaginal tracts) of which surgery confirmed the type of fistula in 86% and the location of the internal opening in 81%.17

In evaluating rectovaginal fistulas, Yee et al.18 concluded that noncontrast endoanal ultrasound was not useful for the identification of the tract of the rectovaginal fistula. They found that the ultrasound study identified only seven of the rectovaginal fistulas. However, 23 sphincter injuries in 25 patients were identified, and they suggest that anal ultrasonography be used preoperatively in patients with rectovaginal fistulas to identify sphincteric defects.

The superiority of MRI over anal endosonography for the assessment of anal fistulae and abscesses has been controversial. Magnetic resonance imaging has been shown to be superior in some studies. For example, in a study of 39 patients conducted by Maier et al.,19 MRI demonstrated a sensitivity of 84% and a specificity of 68% in identifying fistula, whereas endoanal ultrasound showed a sensitivity of 60% and specificity of 21%. Meanwhile, another study evaluating fistulas and abscesses complicating Crohn's disease by Orsoni et al.20 demonstrated that anal ultra sound was more accurate than MRI with sensitivities of 89% and 48%, respectively, in identifying fistulas, and 100% and 55%, respectively, in identifying abscesses.

Herbal Remedies For Acid Reflux

Herbal Remedies For Acid Reflux

Gastroesophageal reflux disease is the medical term for what we know as acid reflux. Acid reflux occurs when the stomach releases its liquid back into the esophagus, causing inflammation and damage to the esophageal lining. The regurgitated acid most often consists of a few compoundsbr acid, bile, and pepsin.

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