Sketchy Path: Neuro - "Hydrocephalus"

Question 1

CSF is made in the ______________.

Answer 1

choroid plexus, which is found in all four ventricles (though the largest part is in the lateral ventricles)

Question 2

The ________________ separate the lateral ventricles from the third ventricle.

Answer 2

interventricular foramina

Question 3

The _____________ is also called the aqueduct of Sylvius.

Answer 3

cerebral aqueduct (like the SiLVer fish leaping out of the pond)

Question 4

Review the three spots that lead from the fourth ventricle to the subarachnoid space.

Answer 4

• Foramen of Luscha (lateral)

* Foramen of Magendi (medial)

Question 5

What are arachnoid granulations?

Answer 5

Bits of arachnoid matter that connect to the dural venous sinuses

Question 6

The most common site of communicating hydrocephalus is clogged ______________.

Answer 6

arachnoid granulations (like the guy whose raft is getting sucked into the pipe –he is communicating his trouble on a walkie-talkie)

Question 7

List the causes of clogged arachnoid granulations.

Answer 7

• Meningitis (like the red spikes on the helmet)
• SAH (like the bleeding spider)
• Fibrosis from scars (fibrous seaweed)

Question 8

Where is the problem in non-communicating hydrocephalus?

Answer 8

Cerebral aqueduct (family stuck in cerebral aqueduct with mother who dropped her phone)

Question 9

Review the causes of non-communicating hydrocephalus.

Answer 9

• Chiari II (dad with II CHeRrIes)
• TORCH infections (tiki torches)
• Colloid cysts in the third ventricle (buoy with #3 on it)
• Extra-gonadal germ cell tumors (germinating trees)
• Posterior fossa tumors (crab on cerebral aqueduct rock)

Question 10

Patients with hydrocephalus typically report headaches that _______________.

Answer 10

are worse in the morning, because gravity helps drain the brain when you are standing

Question 11

Hydrocephalus causes what symptoms?

Answer 11

• Intracranial HTN symptoms (seizure, vomiting, papilledema, AMS, diplopia from abducens palsy)
• Headaches that worsen in the morning

Question 12

Increased pressure in the cerebral aqueduct can press on what structure?

Answer 12

The tectum (represented by the “proTECTed area” sign to the right of the cerebral aqueduct)

Question 13

Compression of the tectum leads to _______________.

Answer 13

vertical gaze palsy due to compression of the superior colliculus

(Think of the setting suns behind the “Call Us” sign near the proTECTed area sign.)

Question 14

In addition to vertical gaze palsy, _______________ is also a sign of Parinaud syndrome (the compression of the tectum).

Answer 14

poor pupillary contraction to light but not accommodation

Think of the beaver whose eyes are large even in the light next to the “accommodations available” sign.

Question 15

What are symptoms of hydrocephalus in children?

Answer 15

• Irritability
• Poor feeding
• Macrocephaly (due to incomplete fusion of cranial bones)

(Think of the baby with the large helmet and the other baby dropping the bottle.)

Question 16

Normal pressure hydrocephalus is thought to develop __________________.

Answer 16

over a long time (like the chronic clock) due to poor arachnoid drains (like the cracked arachnoid pipe)

Question 17

Why do symptoms arise in NPH?

Answer 17

The nerves stretch around the enlarging ventricles (like the guy stretching his chinstrap).

Question 18

The gait of NPH is often described as _________________.

Answer 18

wide-based, magnetic gait (like the old guy stretching his legs wide to get out of the raft and keeping one foot attached to the ground)

Question 19

Imaging of someone with NPH will show ventriculomegaly without ______________.

Answer 19

enlargement of the sulci (otherwise this would be hydrocephalus ex vacuo)