Sinus is a blind granulation tissue lined tract that connects a cavity. It is usually characterized by epithelial surface. Sinus can be in any part of body, and is common.
It is divided into:
- Congenital
- develop from embroyonic phase: urachal sinus, preauricular sinus
- Acquired
- Retained foreign body
- Malignancy
- Improper draiinage
- Inflammatory changes : Crohn's disease
- Chronic infection like TB, Dental abscess
Clinical Features:
- Discharge from opening
- No floor of cavity
- indurated raised edge
- indurated base
- non-mobile
- granulation tissue in lining
Investigation:
- Fistulogram/Sinusogram
- Discharge microscopy: for Gram's, AFB, Cultutre/Sensitivity, Cytology
- Biopsy
- CT sinogram
- Probing
Treatment:
- Main stay is treating the cause
- Can perform excision (if done sample should be sent for histopathology)