Gastrointestinal Flashcards
4 muscles of mastication
Temporalis (close)
Masseter (close)
Lateral pterygoid (open)
Medial pterygoid (close)
Nerve supply of the muscles of mastication
CNV3
Mandibular division of the trigeminal nerve
Function of superior cavity of TMJ
Tanslation
Function of inferior cavity of TMJ
Rotation
Course of CNV3
From Pons
Through foramen ovale
To muscle of mastication and sensory area
Types of fibres in CNV3
Sensory and motor fibres
Innervation of posterior 1/3rd of the tongue
Taste and general sensation
CNIX
Innervation of anterior 2/3rds of the tongue
Taste CNVII
General sensory CNV3
Types of fibre in CN7
Special sensory
Sensory
Motor
Parasympathetic
Course of CN7
From pontomedullary junction
Through temporal bone vie internal acoustic meatus then stylomastoid foramen
To anterior tongue, muscles of facial expression and glands in the floor of the mouth
Connects CNVII to the lingual nerve (CNV3)
Chorda tympani
Innervation of sublingual and submandibular salivary gland
CNVII
Innervation of superior half of oral cavity
CNV2
Innervation of inferior half of oral cavity
CNV3
Innervation of sensory part of gag reflex
CNIX
Innervation of motor part of gag reflex
CNIX and CNX
Local anaesthetic for endoscope blocks action potential in which nerves?
CNV2, CNV3, CNVII, CNIX
Course of CNV2
From pons
Through foramen rotundum
To sensory area (mid-face)
Types of fibres in CNV2
Sensory fibres
Types of fibres in CNIX
Special sensory, sensory, motor, visceral afferent, parasympathetic
Course of CNIX
From medulla
Through jugular foramen
To posterior wall of oropharynx, parotid gland, post. 1/3rd of the tongue
Parotid gland
Crosses the face and secretes into mouth opposite upper 2nd molar
Submandibular gland
Enters floor of mouth and secretes via lingual caruncle
Sublingual gland
Lays in floor of mouth and secretes via several ducts superiorly
Innervation of parotid gland
CNIX
Innervation of submandibular gland
CNVII
Innervation of sublingual gland
CNVII
Innervation of the tongue muscles (except palatoglossus)
CNXII
Type of fibres in CNXII
Motor
Course of CNXII
From medulla
Through hypoglossal canal
To extrinsic and intrinsic muscles of the tongue
Innervation of the circular constrictor muscles of the pharynx
CNX
Innervation of the longitudinal muscles of the pharynx
CNIX and CNX` (mainly)
Innervation of orbicularis oris
CNVII
Nerve supply to oesophagus
Oesophageal plexus
Constrictions of the oesophagus
Cervical constriction by criciopharyngeus muscle
Thoracic constrictions by arch of aorta and left main bronchus
Diaphragmatic constriction from passing through diaphragm
Foregut
Oesophagus to mid-duodenum
Liver + gall bladder
Spleen
1/2 of pancreas
Midgut
Mid-duodenum to proximal 2/3rds of transverse colon
1/2 of pancreas
Hindgut
Distal 1/3rd of transverse colon to proximal 1/2 of anal canal
Intraperitoneal organs
Liver + gall bladder Stomach Spleen 1st part of the duodenum Jejunum Ileum Caecum Transverse colon Sigmoid colon
Retroperitoneal organs
Kidneys Adrenal gland Pancreas Ascending colon Descending colon 2nd-4th part of duodenum
Area of communication between greater and lesser sac
Omental foramen (of winslow)
Peritoneal ligaments
Hepatogastric ligament
Hepatoduodenal ligament
Gastrosplenic ligament
Splenorenal ligament
Placement of needle in paracentesis and the vessel that it avoids
Placed lateral to the rectus sheath
Avoids inferior epigastric artery
Origin of inferior epigastric artery
Arises from external iliac artery medial to the deep inguinal ring
Route of sympathetic nerves from CNS to abdominal organs (5)
1) Leave spinal cord between T5 and L2
2) Enter sympathetic chains
3) Leave sympathetic chains within abdominopelvic splanchnic nerves
4) Synapse at prevertebral ganglia anterior to the aorta
5) Take part in periarterial plexuses towards organs
Route of sympathetic nerve fibres for adrenal gland from CNS to abdominal organs
1) Leave spinal cord at T10-L1
2) Enter abdominopelvic splanchnic nerves
3) Carried with periarterial plexuses to adrenal gland
4) Synapse directly onto cells
Route of parasympathetic nerves from CNS to abdominal organs (vagus) (3)
1) Presynaptic fibres enter abdominal cavity on surface of oesophagus
2) Travel into periarterial plexuses
3) Synapse on ganglia on walls of organs
Route of parasympathetic nerves from CNS to abdominal organs (pelvic splanchnic nerves)
1) S2, 3 and 4 exit spinal cord to innervate smooth muscle/ glands of descending colon to anal canal
Entry level of foregut structure to spinal cord
T6-T9
Entry level of midgut structures to spinal cord
T8-T12
Entry level of hindgut structure to spinal cord
T10-L2
Thoracoabdominal nerves
7th-11th intercostal nerves
Abdominal body wall nerves
Thoracoabdominal nerves Subcostal nerve (T12 anterior ramus) Iliohypogastric nerve (Half of L1 anterior ramus) Ilioinguinal nerve (half of L1 anterior ramus)
Entry level of visceral afferents from appendix)
T8-T10
Liver is protected by which ribs
7-11
How many veins do the hepatic veins from the liver come together as before entering the IVC
3
Level of exit of coeliac trunk from abdominal aorta
T12
Spleen is protected by which ribs
9-11
Which sac are the hepatorenal and sub-phrenic recesses located within
Greater sac
Lowest part of the peritoneal cavity when the patient is supine
Hepatorenal recess
Entry point to spinal cord of visceral afferents from gallbladder
T6-T9
4 parts of the duodenum
Superior part
Descending
Horizontal
Ascending
Exocrine cells of the pancreas
Acinar cells
Endocrine cells of the pancreas
Islets of langerhans
Level of exit point of SMA from aorta
L1 vertebral level
Which sac are the paracolic gutters part of?
Greater sac
Skin around umbilicus anastomoses
Para-umbilical veins drain to hepatic portal vein
Small epigastric veins drain to caval system
Distal end of oesophagus anastomoses
Inferior part drains to hepatic portal vein
Superior part drains to azygous vein
Rectum/anal canal anastomoses
Rectum and superior anal canal drain to IMV
Inferior part of GI tract drains to internal iliac veins
Level at which sigmoid colon becomes rectum
Anterior to S3
Point at which rectum becomes anal canal
Anterior to tip of the coccyx
Nerve supply of levator Ani
Nerve to levator ani and pudendal nerve
Location of internal anal sphincter
Superior two thirds of anal canal
Location of external anal sphincter
Inferior two thirs od anal canal
What muscle is the external anal canal continuous with
Puborectalis
What nerve stimulates contraction of the external anal sphincter?
Pudendal nerve
What nerve stimulates contraction of the internal anal sphincter?
Sympathetic nerves
Which type of nerve fibres stimulate structures in the pelvis?
Sympathetic, parasympathetic and visceral afferent
Which type of nerve fibres stimulate structures in the perineum?
Somatic motor and somatic sensory
Vertebral level of sympathetic fibres travelling to IMA
T12-L2
Vertebral level of somatic motor pudendal nerve fibres
S2, S3, S4
Vertebral level of somatic motor fibres in nerve to levator ani
S3, S4
Vertebral level of visceral afferents and parasympathetic fibres from and to the rectum/ anal canal
S2-S4
Point of exit from pelvis of pudendal nerve
Greater sciatic foramen
Point of entry into perineum of pudendal nerve
Lesser sciatic foramen