congenital esophageal stenosisesophageal stenosis surgerydistal esophageal stenosissevere neuroforaminal stenosisbilateral neuroforaminal stenosislumbar neuroforaminal stenosisstricture and stenosis of esophaguscongenital esophageal strictureintrinsic mild stenosis of esophagusesophageal narrowingcardiovascular stenosisurethral stenosis treatment