Cartoid Triangle

1. CAROTID TRIANGLE

2. BOUNDARIES
ANTERIORLY AND BELOW
SUPERIOR BELLY OF OMOHYOID

3. BOUNDARIES
ANTERIORLY AND ABOVE
POSTERIOR BELLY OF DIGASTRIC AND
STYLOHYOID MUSCLE

4. BOUNDARIES
POSTERIORLY
STERNOCLEIDOMASTOID MUSCLE

5. BOUNDARIES
ROOF
FORMED BY INVESTING LAYER OF DEEP
CERVICAL FASCIA

6. BOUNDARIES
FLOOR
FORMED BY THYROHYOID AND HYOGLOSSUS
ANTERIORLY AND POSTERIORLY BY MIDDLE
CONSTRICTOR AND INFERIOR CONSTRICTOR OF
THE PHARYNX.

7. CONTENTS OF THE CAROTID
TRIANGLE
1. INTERNAL JUGULAR VEIN
2. COMMON CAROTID ARTERY
3. EXTERNAL CAROTID ARTERY
4. INTERNAL CAROTID ARTERY
5. SUPERIOR THYROID ,LINGUAL, COMMON
FACIAL VEINS
6. VAGUS NERVE

8. CONTENTS OF THE CAROTID
TRIANGLE
7. SPINAL ACCESSORY NERVE
8.HYPOGLOSSAL NERVE
9. CERVICAL SYMPATHETIC CHAIN
10.ANSA CERVICALIS
11.LYMPH NODES

9. COMMON CAROTID ARTERY
COMMON CAROTID ARTERY DIVIDES INTO
EXTERNAL AND INTERNAL CAROTID ARTERY AT
THE LEVEL OF UPPER BORDER OF THYROID
CARTILAGE (C4 LEVEL)
AT ITS TERMINATION THERE IS A BULGE CALLED
CAROTID SINUS

10. COMMON CAROTID ARTERY
BEHIND THE TERMINATION THERE IS A SMALL
GREYISH YELLOW BODY CALLED CAROTID BODY.

11. CAROTID SINUS IMPORTANCE
PHYSIOLOGICAL IMPORTANCE OF THE CAROTID
SINUS IS THAT IT CONTAINS BARORECEPTORS
WHEN THERE IS INCREASE IN BLOOD PRESSURE
THERE IS REFLEX SLOWING OF THE HEART RATE
AND PERIPHERAL VASODILATATION.
CAROTID BODY CONTAINS CHEMORECEPTORS
WHEN THE ARTERIAL OXYGEN TENSION FALLS
THERE IS REFLEX INCREASE IN RESPIRATION

12. COMMON CAROTID ARTERY
•
BOTH THE CAROTID SINUS AND THE CAROTID
BODY ARE SUPPLIED BY GLOSSOPHARYNGEAL
NERVE

13. EXTERNAL CAROTID ARTERY
EXTERNAL CAROTID ARTERY GIVES THE
FOLLOWING BRANCHES IN THE CAROTID
TRIANGLE
1.SUPERIOR THYROID
2.LINGUAL
3.FACIAL
4.ASCENDING PHARYNGEAL
5.OCCIPITAL

14. CAROTID TRIANGLE
•
SUPERIOR THYROID, LINGUAL,COMMON
FACIAL VEINS DRAINS INTO THE INTERNAL
JUGULAR VEIN IN THE TRIANGLE

15. VAGUS NERVE
•
VAGUS NERVE DESCENDS BETWEEN THE VEIN
AND ARTERY WITHIN THE CAROTID SHEATH.
•
THE VAGUS NERVE GIVES PHARYNGEAL
BRANCHES AND SUPERIOR LARYNGEAL NERVE
WHICH DIVIDES INTO INTERNAL LARYNGEAL
NERVE AND EXTERNAL LARYNGEAL NERVE.

16. •
SPINAL ACCESSORY NERVE RUNS BACKWARDS
CROSSING THE INTERNAL JUGULAR VEIN.
•
HYPOGLOSSAL NERVE RUNS FORWARDS
CROSSING THE INTERNAL CAROTID ,EXTERNAL
CAROTID AND THE LOOP OF THE LINGUAL
ARTERY.

17. •
CERVICAL SYMPATHETIC CHAIN RUNS OUTSIDE
THE CAROTID SHEATH BEHIND THE ARTERY.

18. ANSA CERVICALIS
•
IS A NERVE LOOP LYING ON THE CAROTID
SHEATH OVER THE INTERNAL JUGULAR VEIN
.IT IS FORMED BY THE UNION OF DESCENDENS
HYPOGLOSSI AND DESCENDENS CERVICALIS .
•
SUPERIOR ROOT ARISES FROM THE
HYPOGLOSSAL NERVE.
•
IT CONTAINS C1 FIBRES
•
INFERIOR ROOT ARISES FROM APR OF C2 AND

19. •
RIBBON MUSCLES OR INFRAHYOID MUSCLES
•
THE RIBBON MUSCLES ARE
•
STERNOHYOID
•
STERNOTHYROID
•
SUPERIOR BELLY OF OMOHYOID
•
INFERIOR BELLY OF OMOHYOID

20. LYMPH NODES
•
CAROTID TRIANGLE HAS DEEP CERVICAL
LYMPH NODES ARE RELATED TO INTERNAL
JUGULAR VEINS

21. CAROTID TRIANGLE
THE COMMON CAROTID ARTERY DIVIDES INTO
EXTERNAL CAROTID ARTERY AND INTERNAL
CAROTID ARTERY, AT THE UPPER BORDER OF
THYROID CARTILAGE LEVEL i.e. 4th CERVICAL
VERTEBRA LEVEL.

22. CAROTID ARTERY
FROM SUPERIOR THYROID ARTERY THE
SUPERIOR LARYNGEAL ARTERY COMES OUT
WHICH ALONG WITH INTERNAL LARYNGEAL
NERVE PIERCES THYROHYOID MEMBRANE.

23. CAROTID TRIANGLE
THE THREE STRUCTURES SEEN IN CAROTID
TRIANGLE ARE COMMON CAROTID ARTERY,
VAGUS AND INTERNAL JUGULAR VEIN.
VAGUS IS SEEN BETWEEN INTERNAL JUGULAR
VEIN AND COMMON CAROTID ARTERY.

24. IN DISSECTION WE FIND THAT ANSA CERVICALIS
IS VERY SUPERFICIALLY PLACED AND IS THIN
AND SUPPLIES ALL STRAP MUSCLES.

25. CAROTID TRIANGLE
DEEP TO STERNOHYOID MUSCLE IS
STERNOTHYROID AND THYROHYOID.

26. BRANCHES OF SUPERIOR THYROID
ARTERY
1. SUPERIOR LARYNGEAL ARTERY
2. STERNOMASTOID BRANCH
3. GLANDULAR BRANCH ( SUPPLIES THYROID
GLAND)
4. INFRA HYOID BRANCH
5. CRICOTHYROID BRANCH

27. BRANCHES OF VAGUS
1.MENINGEAL
2. PHARYNGEAL
3. SUPERIOR LARYNGEAL
4. CARDIAC BRANCHES ( IN NECK)
5. RECURRENT LARYNGEAL

28. THANK
YOU
FOR
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HEARING !