1. PILONIDAL SINUS IMAGING CHALLANGE DIFFERENTIATE Pilonidal sinus from fistula in ano. MERCURY IMAGING INSTITUTE SCO 172-173 SEC 9C CHANDIGARH MERCURY IMAGING CENTRE SCO 16-17 SEC 20D CHANDIGARH

2. RADIOLOGICAL RESPONSIBITY Mathematical Assesment DEFINE THE SEPSIS TRACT / SECONDARY TRACT , RAMIFICATIONS. LOCULI EXTENT ( SACRUM / COCCYX ) SITE ( NATAL CLEFT , PERIANAL , ISHIOANAL , ISCHIO RECTAL , SUPRALEVATOR , INTERSPINCTERIC ) EXTERNAL OPENING USE THE ANAL CLOCK PILONIDAL SINUS ( POSTERIOR TO THE ANAL OPENING). INTERNAL OPENING ENTERIC –SUPPORTS FISTULA IN ANO. Definition to help. Natal cleft : The area of buttock 2 cm posterior to the anal opening Perianal : The area with in 2cm of the anal opening

3. MRI CAN SUPPORT DIFFERENTIATION PILONIDAL SINUS FISTULA IN ANO NATAL CLEFT SEPSIS EXTENSION TO COCCYX EXTENSION TO SACRUM NO INTERSPHINCTERIC SEPSIS NO ENTERIC COMMUNICATION MAY HAVE ISCHIOANAL,PERIANAL,SUPRA-LEVATOR SEPSIS FOLLICULITIS AS ETIOLOGY INTERSPHINCTERIC SEPSIS ENTERIC COMMUNICATION MAY HAVE PERIANAL/ISCHIOANAL/ SUPRALEVATOR SEPSIS. INFECTION IN THE CRYPTOGLANDULAR GLANDS AT DENTATE LINE AND EXTENSION OUTWARDS IS CONSIDERED AS ETIOLOGY.

4. PRESENT CASE CLINICAL BRIEF MOST IMPORTANT IMAGING PLANE 26 YR FEMALE WITH ? PILONIDAL SINUS ? FISTULA IN ANO. ON DIGITAL RECTAL EXAMINATION NO INTERNAL ENTERIC OPENING APPRECIATED IN THE STUDY. SAGITTAL SECTION LONG AXIS OF THE ANAL CANAL

5. NATAL CLEFT SEPSIS WITH LOCULI AND TRACT REACHING THE MEDIAL SIDE OF THE LEFT LABIA

6. PERINATAL SEPSIS WITH LOCULI AND TRACT REACHING THE MEDIAL SIDE OF THE LEFT LABIA. DIFFUSE NATURE OF THE SEPSIS APPRECIATED

7. TRACT ABUTING THE EXTERNAL ANAL SPHINCTER THE INTERSPHINCTERIC PLANE IS NORMAL. EXTERNAL ANAL OPENING

8. LONGITUDINAL EXTENT OF THE TRACT ABUTING THE EXTERNAL ANAL SPHINCTER LOCULI IN THE TRACT RAMIFICATIONS IN THE TRACT ISCHIO ANAL FAT EXTERNAL ANAL SPHINCTER

9. EDUCATION : Natal cleft sepsis with external opening posterior to the anal canal and extension of the sepsis to the coccygeal / sacral region with no interspincertic sepsis and no enteric communication suggest PILONIDAL SINUS as possibility .The fistula in ano near always has intersphincteric sepsis . Primary tract with ramifications / Enetic communication support fistula in ano . Ishioanal , ishiorectal ,translevator , suprasphicteric sepsis can be seen in both the conditions but intersphicteric sepsis is seen only in fistula in ano.