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What is Rigid esophagoscopy is not done in -a) Cervical spine rigidity b) Aortic aneurysmc) Carcinoma esophagus d) Esophageal webe) Lung abscess and explain in detail?
Contraindications of esophagoscopy (rigid type):

Trismus
Aneurysm of aorta
Receding mandible
Advanced heart, liver, kidney diseases (relative contraindication).
Diseases of cervical spine, e.g. cervical trauma, spondylitis, TB, osteophytes, kyphosis, etc.