Circumventricular organs are those areas of the brain that lie outside the blood brain barrier. They contain receptors which detect changes in body fluids such as osmolality and glucose concentration. The circumventricular organs are:
-Subfornical organ
-Subcommisural organ
-Organum vasculosum of lamina terminalis
-Posterior pituitary
-Pineal gland
-Area postrema
-Median eminence

Boundaries of femoral ring are:

Medial – Lacunar ligament
Anterior – Inguinal ligament
Lateral – Septum separating it from the femoral vein
Posterior – Pectineus and covering fascia

Femoral hernia passes through the femoral ring.

Oesophageal hiatus is at T10 vertebral level. Structures passing through esophageal hiatus are:

Oesophagus
Oesophageal branches of left gastric artery and vein
Left and right vagus nerves
Lymphatics
Phreno oesophageal ligament

Q – AIIMS Nov 11, AIIMS Nov 06

Mnemonic for Structures passing through foramen ovale of skull is : OVALE
OVALE stands for:
O – Otic ganglion (Does not pass through it, but lies inferior to it)
V – V3 cranial nerve
A – Accessory meningeal artery
L – Lesser petrosal nerve
E – Emissary vein

MEDIAN TRAP:
Myxoedema
Edema premenstrually
Diabetes
Idiopathic
Acromegaly
Neoplasm
Trauma
Rheumatoid arthritis
Amyloidosis
Pregnancy
Mnemonic 2 - TRAMP:
T – Trauma (occupational)
R – Rheumatiod arthritis
A – Acromegaly
M – Myxoedema
P – Pregnancy
Mnemonic 3: ARMPIT 
A – Acromegaly
R – Rheumatiod arthritis
M – Myxoedema
P – Pregnancy
I – Idiopathic
T – Trauma (occupational)

Mnemonic for the branches of the coeliac arterial trunk is : Left Hand Side (LHS)
Left Hand Side stands for:
Left – Left gastric artery
Hand – Hepatic artery
Side – Splenic artery

Mnemonic for clinical features of Bell’s palsy is: BELL’S Palsy
B – Blink reflex abnormal
E – Earache
L – Lacrimation [deficient, excess]
L – Loss of taste
S – Sudden onset
Palsy of VII nerve muscles

Mnemonic for the nerves supplying the scalp is: GLASS
GLASS stands for:
G – Greater occipital/ Greater auricular
L – Lesser occipital
A – Auriculotemporal
S – Supratrochlear
S – Supraorbital

Mnemonic for Proximal attachment (origin) of deltoid muscle is : CLASP
CLASP stands for:
CL – Clavicle (anterior fibers of deltoid arise from the anterior border and superior surface of lateral third of clavicle)
A – Acromion (middle fibers of deltoid arise from the lateral border of acromion process of scapula)
SP – Spine of the scapula (posterior fibers of deltoid arise from the posterior border of spine of scapula)
Note : The fibers of the deltoid converge and is inserted into the deltoid tuberosity of humerus.

Mnemonic for Deep branches of Femoral artery is : “Put My Leg Down Please”
It stands for:
Put – Profundus femoris (deep femoral artery)
My – Medial circumflex femoral artery
Leg – Lateral circumflex femoral artery
Down – Descending genicular arteries
Please – Perforating arteries