Esophageal varices is a condition related to liver disease. 
Portal hypertension is the liver causes preexisting venous channels to dilate in an effort to decompress the high-pressure portal venous system. The result is esophageal and gastric varices.
The thin walled varices in the lower esophagus can bleed spontaneously. Bleeding may vary from oozing to hemorrhage. Band ligation or sclerotherapy Injection controls bleeding and prevents rebleeding.
Medication injected into the varices via an injection catheter inserted thru the endoscope, causes clotting of the varices. This is followed by a fibrotic reaction and eventual obliteration of the varix.