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Saturday, March 31, 2018

Tongue anatomy

                    https://anatomyaiimsrajesh.blogspot.com/            

                               Tongue

​ Highly muscular organ of Deglutition, taste and speech.
● Divided in two parts by Sulcus
   Terminalis(V shaped) with median
   depression￾ForamenCaecum [upper end
   of embryonic thyroid diverticulum
   (thyroglossal duct).
1. oral ( presulcal) part- anterior ⅔ rd. papilla present here.
2. pharyngeal(post sulcal part)- posterior ⅓ rd. devoid of papillae.

Muscles of Tongue​:
1. Intrinsic: superior and inferior
    longitudinal, transverse and vertical
2. Extrinsic: 4 pair of muscles
    a) Genioglossus- protrude its apex from
         mouth, also diverses tongue to
         opposite side.
    b) Hyoglossus- depresses tongue.
    c) Styloglossus- up and backward
        movement.
    d) Palatoglossus- elevates root of tongue.

Chondroglossus- also present nearly similar to hyoglossus but has separate fibers.

Note: All muscles of tongue supplied by Hypoglossal nerve except Palatoglossus.

Palatoglossus is supplied by pharyngeal plexus (formed by IX, X and superior cervical sympathetic ganglia).


Arterial supply​: ​
  Lingual artery- branch from anterior
                surface of external carotid artery.

3 branches:
    dorsal lingual,
    sublingual and
    deep lingual artery.

Venous Drainage​:​
   Lingual veins
   Joins facial and anterior division of
   Retromandibular vein to form common
   facial vein.
   Finally drains into Internal jugular vein.

Lymphatic Drainage​:​
  Lingual tonsils
  present in mucosa of pharyngeal part of
  dorsal surface Of tongue

 lymphatic vessels.

Anterior part drain in-
  marginal and central vessels
Posterior part drain in -
  Dorsal lymph vessels
Central part drain in-
  bilaterally- important to dissect both
  side in malignancy.

Finally all drain in submental, submandibular, jugulo-omohyoid and jugulo-digastric nodes.


Sensory Innervation of tongue (for general sensation):
Anterior 2/3rd-
    Lingual Nerve branch of mandibular
    division of trigeminal nerve.
Posterior 1/3rd-
    Glossopharyngeal nerve.
Near valleculae-
    Internal laryngeal branch of Vagus.

Taste:
Salt( NaCl), Sour(acidic),Sweet(sugar), Bitter( quinine) and Umami( delicious taste)

Innervation of Tongue for Taste sensation​:
1. Chorda Tympani​-
   A branch of VIIth nerve, travels via
   Lingual nerve & supplies anterior
   part of tongue excluding circumvallate
   papillae.

Note: Lingual nerve gives only sensory innervation- no taste sensation.

2. Facial nerve​-
    also innervates inferior part of soft palate
    for taste sensation.

3. Glossopharyngeal nerve​-
    Taste sensation in circumvallate papillae,
    post sulcal part of Tongue , palatoglossal
    arch and oropharynx.

4. Vagus Nerve​-
    Extreme pharyngeal part of tongue and
    epiglottis via internal laryngeal branch.


Thank you all,
Questions and suggestions are always welcomed.

Dr. Rajesh Kumar
Resident
Department of Anatomy
AIIMS, New Delhi

Cerebellar peduncles

Peduncle      Afferent              Efferent

Superior cerebellar peduncle

Afferent
  1.Ventral spinocerebellar tract
  2.Tectocerebellar fibers
  3.From locus Coeruleus
     (noradrenergic)
  4. Trigeminothalamic fiber

Efferent
  1. Cerebellothalamic fibers
  2. Cerebellorubral fibers

Middle cerebellar peduncle

Afferent
Pontocerebellar fibers

Inferior cerebellar peduncle

Afferent
  1.Olivocerebellar fibers
  2.Dorsal spinocerebellar tract
  3.Cuneocerebellar fibers
  4.Vestibulocerebellar fibers
  5.Arcuate nucleus
  6.Trigeminal sensory nucleus
  7.Precerebellar reticular nucleus

Efferent
  Cerebellovestibular fibers


Thank you. .
Soon visit for further facts.

Questions and suggestions are always welcomed.
Dr. Rajesh Kumar
Resident
Department of Anatomy
AIIMS, New Delhi

Foramina in skull

Foramen or canal Structures passing through
1. Carotid Canal
    Internal carotid artery and
    sympathetic plexus around artery

2. Foramen Lacerum
    Generally filled with cartilage
    no structure passes through it.
    Sometimes, Nerve of pterygoid
    canal(vidian nerve) passes.

3. Petrotympanic fissure
    Chorda tympani nerve
    Anterior ligament of malleus &
    Anterior tympanic branch of Maxillary
    artery.

4. Foramen magnum
     1. Anterior part-​ apical ligament of dens,
                                    vertical band of
                                    cruciate ligament,
                                    membrana tectoria.
     2. Posterior part-​ lower part of medulla,
                                     meninges.
     3. Through subarachnoid space-​ Spinal
                                                accessory nerve,
              anterior and posterior spinal artery,
                                    Vertebral arteries and
                 sympathetic plexus around artery.

5. Hypoglossal canal -
      Hypoglossal nerve,
      meningeal branch of hypoglossal nerve,
      meningeal branch of ascending
      pharyngeal artery &
      emissary vein

6. Stylomastoid foramen -
       Facial nerve,
       stylomastoid branch of posterior
       auricular artery

7. Mastoid canaliculus(Arnold’s canal)
        Auricular branch of vagus(Arnold’s
        nerve or Alderman’s nerve)

8. Tympanic canaliculus
        Tympanic branch of IXth
        (Jacobson’s nerve)

9. Incisive foramen
        Terminal part of greater palatine
        vessels and nasopalatine nerve

10. Greater palatine foramen
        Greater palatine vessel and
        anterior palatine nerve

11. Lesser palatine foramen
      Middle and posterior palatine nerves

12. Palatovaginal canal
      Pharyngeal branch of pterygopalatine
      ganglia & pharyngeal branch of
      maxillary artery

13. Vomerovaginal canal
      Generally closed,
      sometimes pharyngeal branch of
      pterygopalatine ganglia

14. Foramen of vesalius (emissary
       sphenoidal F)
       Emissary vein connecting cavernous
       sinus with pterygoid plexus of veins

15. Foramen caecum
      Generally closed,
      occasionally veins from nasal mucosa to
      superior sagittal sinus.
      Failure of closure causes Nasal dermoid
      and nasoethmoidal encephalocoele.

16. Foramen rotundum
      Maxillary nerve
17. Dorello’s canal
       Interdural space near petrous apex,
       petroclival venous confluence,
       filled with blood from sinuses.
18. Facial hiatus
      Greater petrosal nerve

19. Foramen ovale-
      MALE-
      mandibular nerve,
      accessory meningeal artery,
      lesser petrosal nerve &
     emissary vein connecting cavernous
     sinus with pterygoid venous plexus.

20. Foramen spinosum-
      Middle meningeal vessels and
      meningeal branch of mandibular nerve
      (nervous spinosus)

21. Jugular foramen- three parts by
       intrajugular process
      1. Anterior part-
          inferior petrosal sinus &
          meningeal branch of ascending
          pharyngeal artery
      2. Middle part-
          IX,X & XI th cranial Nerves
      3. Posterior part-
          Internal jugular vein & meningeal
          branch of occipital artery

22.  Internal acoustic meatus-
       VII & VIIIth nerve,
       nervus intermedius &
       labyrinthine vessels.



Thank you. .
Soon visit for further facts.

Questions and suggestions are always welcomed.
Dr. Rajesh Kumar
Resident
Department of Anatomy
AIIMS, New Delhi