Abdomen Anatomy Flashcards
What structure pierces the buccinator muscle?
Stensen’s (parotid) duct
Name the bones that make the hard palate?
Maxillary bone (anteriorly) Palatine bone (posteriorly)
The soft palate (uvulae) has 5 muscles. 4 of which are innervated by the vagus nerve what is the only muscle of the soft palate not innervated by the vagus nerve?
Tensor veli palatini muscle – Trigeminal nerve
What is the function of the tensor veli palatini?
Tenses the soft palate, flattens it and prevents food from entering the nasal cavity. (Tensor = tense, Veli = veil, Palatini = palate)
The tongue is divided into the anterior 2/3 and the posterior 1/3 by the ‘V’ shaped terminal sulcus. The foramen caecum lies at its apex. What is the embryological significance of this structure?
This was the site at which the embryonic thyroid gland originated before descending down into the neck. In some individuals, the duct connecting the duct to the thyroid (thyroglossal duct) does not obliterate
What nerve supplies the motor innervation to the tongue?
Hypoglossal nerve (CNXII)
What nerve gives the general + special sensation to the posterior 1/3 of the tongue?
Glossopharyngeal nerve (CNIX)
What nerve gives the general sensation to the anterior 2/3 of the tongue?
Trigeminal nerve (Specifically the lingual branch of V3)
What nerve gives the special (taste) sensation to the anterior 2/3 of the tongue?
Chorda tympani branch of the facial nerve (CNVII)
Name the 3 salivary glands?
Parotid, submandibular, and sublingual
Name the 3 structures travelling through the parotid gland?
1) External carotid artery 2) Facial nerve 3) Retromandibular vein
What is the innervation of the parotid gland?
Glossopharyngeal nerve (NOT FACIAL)
What are the 4 parasympathetic cranial nerves?
3 (Oculomotor), 7 (Facial), 9 (Glossopharyngeal), and 10 (Vagus)
What is the innervation of the submandibular and sublingual glands?
Facial nerve
The Parotid (Stensen’s) duct will pierce the buccinator and enter the oral cavity at what location?
Adjacent to upper second molar
What are the 3 divisions of the pharynx?
Nasopharynx, Oropharynx, Laryngopharynx
What are the borders of the nasopharynx?
Base of skull (Choanae) 🡪 Soft palate
What are the borders of the oropharynx?
Soft palate 🡪 Epiglottis
What are the borders of the laryngopharynx?
Epiglottis 🡪 Cricoid cartilage (C6)
What structure lies in the most posterior aspect of the nasopharynx and what structure does it sit close to?
Adenoids (pharyngeal tonsil)
Opening of the eustachian tube
What is the clinical correlate of the relationship between the adenoids and eustachian tube?
Enlarged adenoids can compress opening of the eustachian tube -> middle ear infection
What gives the sensory innervation to the nasopharynx?
Maxillary nerve (V2 of trigeminal nerve)
What two folds (of muscle) sit anterior and posterior to the palatine tonsil?
Palatopharyngeus (Sitting posterior, closer to the pharynx) and Palatoglossus (Sit anterior, closer to the glossus or tongue)
What is the sensory innervation of the oropharynx?
Glossopharyngeal nerve
What is the sensory innervation of the laryngopharynx?
Vagus nerve
What is the valleculae?
This is a space that sits anterior to the epiglottis – it is clinically relevant as food and foreign bodies can get caught here
What are the 4 constrictions of the oesophagus?
Importance of these constrictions?
As it crosses the: Arch of aorta, Left main Bronchus, Cricoid cartilage + Diaphragm (ABCD)
Most likely sites for a bolus of food to become trapped
Which part of the stomach is guarded by the lower oesophageal sphincter?
Cardia
Damage to the lower oesophageal sphincter predisposes you to which condition?
GORD 🡪 Barrett’s oesophagus
What is the pathophysiology behind Barrett’s oesophagus?
Reflux of gastric acid contents leads to metaplasia where the usual stratified squamous epithelium is replaced by the columnar epithelium you would usually see in the stomach. In about 10% of the patients with Barrett’s oesophagus, Dysplasia occurs (leading to oesophageal cancer)
The final portion of the stomach is named the pylorus and it controls the emptying of gastric contents into the duodenum. How may you get malfunctioning of the pyloric sphincter?
Hypertrophy of the Pyloric sphincter leading to pyloric stenosis. Seen in paediatrics with the classic ‘projectile vomiting’ and the ‘olive shaped mass’ on abdominal palpation
Which part of the duodenum is the only part to be intraperitoneal?
First (superior) part. Parts 2-4 are retroperitoneal
On the second part of the duodenum we find the major and minor duodenal papillae. What structures open up here?
Major duodenal papillae – Ampulla of Vater/Hepatopancreatic ampulla.
Minor duodenal papillae – accessory pancreatic duct
The Ampulla of vater/Major duodenal papillae marks the beginning of which portion of the gut?
Midgut
What is the blood supply to the uncinate process + head of the pancreas?
Pancreatoduodenal artery 🡪 gastroduodenal 🡪 common hepatic N.B the pancreatoduodenal A can also be subdivided into the anterior + posterior divisions with the posterior division coming off the SMA. This is beyond the scope of the session.
What is the blood supply of the neck body and tail of the pancreas?
Splenic artery
Most duodenal ulcers occur posteriorly (95%) and can often lead to haemorrhage. The reason for this is that they can erode into a blood vessel that runs posteriorly to the duodenum. Name this artery?
Gastroduodenal artery
At what vertebral level does the Coeliac trunk (the blood supply to the foregut) come off of the abdominal aorta?
T12
What are the 3 branches of the coeliac trunk?
1) Common Hepatic 2) Left gastric 3) Splenic
What is the sympathetic innervation to the stomach and foregut?
Greater splanchnic nerve (T5-T9)
How does the rotation of the stomach affect the position of where the left and right vagus nerve sits?
As the stomach rotates over to the right-hand side of the body 🡪 Left vagus nerve sits anteriorly to the stomach, right vagus nerve sits posteriorly to the stomach
Which lobe of the liver sits adjacent to the gallbladder?
Quadrate lobe
The liver develops within what structure?
Ventral mesogastrium
Which ligament separates the right and left lobe of the liver?
Falciform ligament
The falciform ligament continues as what structure?
Ligamentum teres (round ligament)
What was the round ligamentum embryological remanent?
Umbilical vein
The ligamentum venosum is adjacent to the caudate lobe of the liver. What was the name of this structure during embryonic development?
Ductus venosum
What was the function of the Ductus venosum?
A vessel that connected the umbilical vein to the IVC. This allows the venous circulation to bypass the hepatic circulation and go straight to the IVC
Name the portal triad?
Proper Hepatic Artery, Common Bile duct, Hepatic portal vein
Name the two portions of the lesser omentum?
Hepatogastric ligament + Hepatoduodenal ligament
What runs within the free edge of the lesser omentum (aka the hepatoduodenal ligament)?
Portal triad