Internal Capsule

Question 1

Internal capsule

Answer 1

Broad projection fibers bundle

Question 2

Site

Answer 2

1. Lies between lentiform nucleus (lateral) and caudate head and thalamus (medial)
2. Almost completely divides corpus striatum into 2 parts
3. Continuous above with corona radiata and below with basis pedunculi of midbrain cerebral peduncles

Question 3

Shape

Answer 3

In horizontal section, it has V shaped appearance:
1. Short anterior limb
2. Apex (genu)
3. Longer posterior limb
4. Retro-lenticular part
5. Sub-lenticular part

Question 4

Short anterior limb site

Answer 4

Lies between lentiform nucleus (lateral) and caudate nucleus head (medial)

Question 5

Short anterior limb contents

Answer 5

1. Fronto-pontine fibers
2. Anterior thalamic radiation

Question 6

Genu site

Answer 6

1. Angle at junction of anterior and posterior limbs
2. Fits into interval between caudate head (in front) and thalamus (behind)

Question 7

Genu contents

Answer 7

Cortico-nuclear fibers

Question 8

Longer posterior limb site

Answer 8

Lies between lentiform nucleus (lateral) and thalamus (medial)

Question 9

Longer posterior limb contents

Answer 9

1. Frontopontine fibers
2. Corticospinal fibers
3. Corticorubral fibers
4. Corticostriate fibers
5. Superior thalamic radiation

Question 10

Retrolenticular part site

Answer 10

Lies behind lentiform nucleus

Question 11

Retrolenticular part contents

Answer 11

1. Optic radiation
2. Parietopontine fibers
3. Occipitopontine fibers

Question 12

Sublenticular part site

Answer 12

Lies below lentiform

Question 13

Sublenticular part contents

Answer 13

1. Auditory radiation
2. Temporopontine fibers

Question 14

Blood supply

Answer 14

1. Anterior cerebral artery
2. Middle cerebral artery
3. Anterior choroidal artery

Question 15

Anterior cerebral artery supply

Answer 15

Posterior part of anterior limb is supplied by the central branches

Question 16

Middle cerebral artery supply

Answer 16

Posterior part of anterior limb, genu and anterior part of posterior limb are supplied by the central branches

Question 17

Anterior choroidal artery

Answer 17

Branch of the ICA
Posterior part of posterior limb, retrolentiform and sublentiform