GI Flashcards
Mylohyoid Muscle
floor of the mouth
Vestibule
area in front of the teeth, behind the lips
Oral cavity
area within the teeth
Teeth and gingivae nerve supply
superior and inferior alveolar nerves and maxillary and mandibular branches of trigeminal
Teeth and gingivae blood supply
superior and inferior alveolar vessels
Intrinsic tongue muscles
change shape of the tongue
Extrinsic tongue muscles
move the tongue itself
What is the root of the tongue anchored to?
mandible and hyoid bones
What epithelium are the tongue and palate covered by?
Keratinised stratified squamous epithelium
What covers the tongue surface
papillae bearing taste buds
Where are vallate papillae found?
at the root of the tongue
Vascularature of the tongue?
Artery- lingual artery (frome external carotid). Vein- lingual vein (to IJV)
Motor supply of tongue
hypoglossus (CNXII) apart from palatglossus which is vagal (CNX)
Sensation supply of tongue
post 1/3 glossopharyngeal, anterior 2/3 lingual mandibular of trigeminal nerve (CNV)
Taste supply of the tongue
post 1/3 glossopharyngeal, anterior 2/3 chorda tympani branch of the facial nerve (CNVII)
Temporomandibular joint
bilateral synovial articulation between mandible and temporal bone
What are the muscles of mastication
Massater, Temporalis, Medial and pterygoids
Styloglossus
raises posterior part of tongue during swallowing
Palatoglossus
raises posterior part of tongue during swallowing
What closes the laryngeal orifice
aryepiglottic and oblique arytenoids
What muscles make up the soft palate
tensor and levator veli palatine, palatoglossus, palatopharyngeus and uvular
What makes up the hard palate
palatal process of the maxilla and the horizontal palatine bones
What vessel supplies the palates
branches of the maxillary artery
What innervates the palates
pharyngeal plexus, other than the tensor veli palatini which is supplied by CNV3
What muscles make up the external layer of the pharynx
smooth muscle constrictors- superior, middle and inferior
What muscles make up the internal layer of the pharynx
palatopharyngeus, salpingopharyngeus, stylopharyngeus
What 2 groups of muscles make up the larynx?
Suprahyoid and Infrahyoid
What are the suprahyoid muscles, and what do they do?
mylohyoid, geniohyoid (goes around digastric tendon), digastrics (ant. + post. bellies). All act to elevate the larynx/hyoid
What are the infrahyoid muscles, and what do they do?
Sternohyoid (top layer), omohyoid (loop to scapula), sternothyroid and thyrohyoid. All act to depress the larynx/hyoid
Parotid gland location
side of cheek, duct opens on inside of cheek wall (beside 2nd upper molar)
Parotid gland innervation
glossopharyngeal nerve (otic ganglion)
What runs through the parotid gland?
facial nerve (chorda tympani), external carotid artery (maxillary and temporal branches) and retromandibular vein
Submandibular duct location
beneath jawline, duct opens lateral to lingual frenulum.
Sublingual duct location
below the tongue, duct opens around the underside of the tongue
Sublingual duct innervation
facial nerve, chorda tympani, submandibular ganglion innervation
What are the 4 narrowings of the oesophagus
cricopharyngeal spinchter (cervical), aortic arch and left main bronchus (thoracic), esophageal hiatus (diaphragmatic) and the GO junction
Where does the oesophagus begin
C6- level of the cricoid cartilage
Oesopaheal mucosa epithelium
stratified squamous
Oesophageal mucosa epithelium
stratified squamous
Relations of oesophagus
anterior to vertebral fascia, posterior to trachea
Where does the oesophagus enter the abdomen, and what with
Through right crus of diaphragm with vagus nerve at T10
Oesophageal blood supply?
Upper 1/3 inferior thyroid artery, middle 1/3 off thoracic aorta, lower 1/3 left gastric artery
Oesophageal lymph drainage
Posterior mediastinal nodes
Where is the lesser omentum found?
between stomach and liver
What is the lesser sac?
subsection of peritoneal cavity- posterior to stomach ad anterior to retroperitoneal organs
What is the greater omentum
2 double layers (4 layers) over the abdominal organs
What connects the greater and lesser sacs?
Omental foramen/epiploic foramen/foramen of Winslow
Sign of upper GI malignancy
Enlarged supraclavicular lymph node
How many parts in the duodenum
4-superior, descending, inferior, ascending
Which parts of the duodenum are retroperitoneal
2nd + 3rd
Which parts of the duodenum are intraperitoneal
1st + rth
Duodenum epithelium?
Columnar with villi and circular folds
What is the function of the duodenum
regulation of stomach emptying, mucus/enzyme/bile secretion
What is the Sphincter of Oddi?
The major duodenal papilla
What is the Sphincter of Vater
comes form the common bile duct and creates a small bulge in the duodenal wall
What is duodenal secretion stimulated by
secretin and the PSNS
What is the blood supply and innervation of the duodenum
Dual, 1st + 2nd parts and pancreas from coeliac axis and 3rd + 4th parts superior mesenteric axis
Pancreas Relations (internal)
Head lies in curve of duodenum, tail in splenic hilum. In foregut, epigastric region. Retroperitoneal.
Where does the duct of the pancreas open?
At the major duodenal papilla.
What is pancreatic secretion stimulated by?
cholecystokinin (endocrine) and PSNS
What is the pancreas blood supply?
splenic artery (along ant/sup pancreas) and the superior anterior pancreatic-duodenal arteries. Corresponding veins drain to portal system.
Where is the spleen located.
Under 9th/10th//11th ribs on LHS. Foregut. Intraperitoneal.
Spleen bloody supply
splenic artery and vein
Where is the gallbladder
behind the tip of 9th costal margin on RHS
What is inflammation of the gallbladder called?
Murphy’s sign
Where is the pancreas found? (surface)
Neck overlies L1-L2, neck at L1, transpyloric plane
Lobes of the liver
left, right, caudate and quadrate
Liver location
foregut, intraperitoneal (covered by peritoneum aisde from bare area)
Where does the falciform ligament attach to?
abdominal wall and diaphragm
What is the porta hepatis
a deep fissure in the inferior surface containing the L + R hepatic arteries and the hepatic portal vein
Ligamentum teres
obliterated umbilical vein
Ligamentum arteriosum
obliterated ductus venosus
Gall bladder location (internal)
foregut, intraperitoneal
What stimulates secretion of the gallbladder
cholecystekinin
Blood supply of the gall bladder
branch of the right hepatic artery
Gallstones risk factors
Fat, Fair, Female, Fertile, Forty (+OCP and rapid weight loss)
What can gallstones be made of?
cholesterol/mixed/pigment
What is the arcuate line
lower edge of posterior sheath, ends about 1/3 way between umbilicus and pubic crest
Where does the inguinal ligament attach?
Attaches the ASIS to the pubic tubercle
Where does the deep inguinal ring run?
Through the transversalis fascia, lateral to inferior epigastric vessels
Where does the superficial inguinal ring run?
through the aponeurosis of the external oblique
What forms the superior border of the inguinal canal?
Lowe edge of internal oblique, transvere abdominis
What forms the inferior border of the inguinal canal?
Inguinal Ligament
What forms the posterior border of the inguinal canal?
Transversalis Fascia (laterally), Conjoint tendon (medially)
What forms the anterior border of the inguinal canal?
Skin, superficial fascia and aponeurosis of the external oblique
What is contained in the inguinal ligament? (Male and female)
Male: spermatic cord
Female: round ligament of uterus
What is the mid-inguinal point and what can be found there?
Halfway between ASIS + pubic symphysis.
Femoral artery passes just underneath it.
What is the mid-point of the inguinal ligament and what can be found there?
Halfway between ASIS and the pubic tubercle.
Opening to inguinal canal is just above this point.
What region is prone to herniation?
The inguinal region- deep inguinal ring (espedcially in males) and femoral canal.
Where are direct inguinal hernias from?
Hasselbach’s triangle
Where are indirect inguinal hernias from?
Usually due to embryonic failure to close inguinal ring.
How can you identify the jejunum?
Large, closely set folds. Darker colour, greater vasculairty from vasa recta (straight vessels). No Peyer’s patches.
What can you identify the ileum?
No folds in the terminal ileum. Paler colour, reduced vascularity, less vasa recta more arcades (complex). Peyer’s patches (looks white)
Where can you find the jejunum?
LUQ/Umbilical region. Intraperitoneal- attached by mesentery.
Where can you find the ileum?
RLQ/Suprapubic region. Intraperitoneal- attached by mesentery.
What is diverticular disease?
Multiple/single mucosal hernias through bowel wall muscle. Normally sigmoid/descending colon.
Where can you see the aorta on a radiograph?
behind diaphragm at T12
Where can you see the coeliac trunk on a radiograph?
at upper L1
Where can you see the SMA on a radiograph?
at lower L1
Where can you see the renal arteries on a radiograph?
at L2
Where can you see the IMA on a radiograph?
at L3
Where can you see the bifurcation to common iliac arteries on a radiograph?
at L4
Where does the greater omentum attach to on the large bowel?
Transvere colon
Which parts of the large bowel are retroperitoneal?
Ascending and descending
Which parts of the large bowel are intraperitoneal?
Transverse and Sigmoid
What are the taeni coli
3 longitudinal muscle bands that have a ‘purse string’ effect
What is the rectum?
A dilatable ‘holding area’ above the levator ani in the pelvis
What is the blood supply of the rectum?
superior rectal artery (from IMA) and the middle rectal artery (from internal iliac)
Where does lymph from the rectum drain?
Upper (canal) –> inferior mesenteric nodes
Lower (canal) –> internal iliac nodes
Where does the anal canal travel?
Anorectal ring –> anus
What is the pectinate line?
Was an embryological division. Divides the upper and lower anal canals
What is the blood supply + drainage of the upper anal canal?
Superior rectal artery, super rectal vein
What is the blood supply + drainage of the lower anal canal?
Inferior rectal artery, inferior rectal vein
What is the innervation of the upper anal canal?
Autonomic innervation from hypogastric plexus
What is the innervation of the lower anal canal?
somatic innervation by inferior rectal nerves
What is the function of the puborectalis
aids anal continence
What is tenesmus
a feeling of incomplete evacuation
What are portosystemic anastomoses?
Hole between systemic and portal circulation. Can be oesophageal (varices), rectal, paraumbilical, retroperitoneal, intrahepatic.
