Hydrocephalus: Diagnosis and Management

00:01 What about a non-communicating hydrocephalus? This can behave like a mass effect.

00:08 Mass such as a tumor or an extrinsic obstruction of the normal CSF drainage pathway.

00:14 Recall a few slides back, the choroid plexus, all the way to the subarachnoid space, is a defined pathway.

00:21 Any obstruction along that pathway can cause a non-communicating hydrocephalus.

00:26 Remember, the brain has had less time to compensate and more likely to develop intracranial hypertension.

00:34 Besides our physical and history, imaging diagnosis can be helpful.

00:39 Generally speaking, we get a CAT scan.

00:41 The arrow is pointing to you a very decreased amount of lateral ventricle space.

00:47 In this MRI image, you notice quite dilated ventricles.

00:52 This probably represents a CSF accumulation due to the lack of absorption rather than an obstruction.

00:58 Now, you’ve diagnosed hydrocephalus.

01:02 When do we need to treat it? Well, indications for treatment, which includes a ventricular peritoneal shunt, is when the patient becomes symptomatic.

01:11 In this shunt procedure, a catheter is placed between the ventricles, tunneled under the skin and introduced into the abdomen.

01:19 Although a fairly routine procedure, it does contain some complications.

01:23 Mostly, as you can imagine, if the catheter is in the abdomen, intestines can loop around it.

01:28 This catheter can be clogged and becomes dysfunctional.

01:32 It may need to be replaced.

01:34 Additionally, also remember, sometimes the ventricular peritoneal shunt is actually a ventricular plural shunt.

01:41 That's when the ventricular drainage catheter is placed into thoracic – into the thoracic space as opposed into the abdomen.

01:49 Some reasons that neurosurgeons may choose to place it into the thoracic space as opposed to the abdominal space is because of prior surgeries in the abdomen.

01:58 As we previously described, this catheter sits in the ventricle, is tunneled, as you can see in this schematic, either into the thoracic space or into the abdomen.

02:08 Now, it’s time to remind you of some clinical pearls and high-yield information on hydrocephalus.

02:14 Remember the classic findings of normal pressure hydrocephalus? Although rare, it's a popular test question.

02:21 It requires a high index of suspicion, so you as a clinician should think about normal pressure hydrocephalus.

02:28 If the clinical scenario presents with classic findings, you have your answer.

02:34 And remember, Arnold-Chiari syndrome.

02:37 This syndrome is a skull malformation that can cause cerebellar tonsils to displace inferiorly.

02:44 This actually causes an obstruction.

02:46 So, this would not be an example of normal pressure hydrocephalus.

02:50 This is so-called non-communicating hydrocephalus.

02:54 This is high-yield information.

02:56 I’d encourage you to commit it to memory.

02:59 Thank you very much for joining me on this discussion of hydrocephalus.