Oesophagus

Question 1

How long is the oesophagus and what is it’s diameter?

Answer 1

25cm, 2cm

Question 2

What are the three constrictions of the oesophagus?

Answer 2

cervical - beginning of pharyngeo oesophageal junction caused by cricopharyngeusa muscle 15 cm from the incisors
thoracic - where it is crossed by the arch of the aorta 22.5cm from incisors
diaphragmatic - where it passes through the oesophageal hiatus 40cm from incisors

Question 3

what is the difference in the muscle in the top two thirds and the bottom third?

Answer 3

top - voluntary striated and bottom is smooth

Question 4

where does the oesophagus terminate?

Answer 4

where it enters the stomach at the cardiac orifice of the stomach to the left of the midline at the level of the 7th costal cartilage at the t11 vertebrae

Question 5

oesophagogastric junction

Answer 5

left of t11 vertebra on the horizontal plane that passes through the tip of the xiphoid process.

Question 6

where is the z line?

Answer 6

immeadiately superior to the oesophagogastric junction where the oesophageal mucosa abruptly changes to gastric mucosa

Question 7

blood supply to oesophagus

Answer 7

oesophageal branches of the aorta, inferior thyroid artery and the oesophageal branches of the left gastric artery

Question 8

venous drainage of the oesophagus

Answer 8

upper part -brachiocephalic vein
middle part - azygous vein
lower part - left gastric vein

Question 9

nerve supply

Answer 9

upper part is the recurrent laryngeal nerve

lower part is the oesophageal plexus from the vagus nerve

Question 10

histology

Answer 10

serosa on the outside - fibrous coat
apart from the thoracic part which is called the adventitia
muscularis externa -longitudinal and cirular
submucosa - fatty and alveolar CT, vessels, nerves, lymphatics
mucosa - longitudinal folds and lined with stratified squamous non keratinised epithelium