0:00

The most ominous of the causes of ocular

0:04

calcification is from retinoblastoma.

0:08

The calcification of retinoblastoma

0:10

may be chunky or can be fluffy.

0:16

The important thing about evaluation of patients and the

0:20

calcification associated with retinoblastoma

0:22

is to make sure that you don't get too

0:27

focused on the large tumor, such that you neglect the

0:35

second retinoblastoma

0:37

because of the implications of therapy.

0:40

This globe,

0:41

because over half of it is involved with retinoblastoma,

0:47

likely will require enucleation.

0:49

This globe also needs treatment, so that way it doesn't

0:52

grow in the same fashion as the left globe.

0:56

But this one may be able to be treated with local

0:59

therapy, as opposed to enucleation.

1:03

Retinoblastoma is one of the cancers that

1:07

can occur in the first year of life.

1:10

As I mentioned previously,

1:12

the entity may occur in one-third of cases

1:16

in a bilateral fashion. When it does,

1:18

we usually ascribe it to the familial form,

1:22

which is associated with the RB1 tumor suppressor gene

1:26

on the 13th chromosome.

1:29

90% of retinoblastomas calcify. And as I said,

1:33

there is a number of possible etiologies that may

1:37

lead to absence, red reflex, or leukocoria,

1:42

but most of these do not show calcification.

1:46

Therapy for retinoblastoma may include when a tumor

1:52

is unilateral and small in size, cryoablation,

1:57

laser photocoagulation, chemotherapy,

2:00

brachytherapy or plaque radiotherapy.

2:04

However, when the tumor is large and unilateral

2:08

and involves greater than half of the globe,

2:11

enucleation is typically performed.

2:14

In those cases of bilateral retinoblastoma,

2:18

as you saw in that last example,

2:20

enucleation occurs in the worst eye and then the smaller

2:24

tumor in the second eye is usually treated

2:27

with one of these entities.

2:29

What one doesn't want to have is to leave

2:31

a child who has bilateral blindness.

2:34

Here is an example of MRI in a 13-month-old child,

2:39

and we are looking at the FLAIR scan

2:44

and the post-gadolinium T1-weighted scan,

2:47

and then we have a separate child over here.

2:50

This patient has retinoblastoma,

2:54

which is bilobed in the left globe,

2:57

but also has an additional finding

3:00

in the contralateral globe.

3:02

So here is the temporal retinoblastoma of the second

3:08

eye, and the larger retinoblastoma of the left eye.

3:14

These are seen on post-gadolinium coronal

3:17

scans as showing contrast enhancement.

3:20

The child

3:22

seen in the lower image, on the right, was the example of

3:26

the case that was shown as a case study,

3:30

in which one has a very large retinoblastoma of the globe,

3:34

as well as spread along the optic nerve intracranially

3:40

and even affected, ultimately,

3:42

the optic chiasm on the images above.

3:46

As I mentioned,

3:47

leukocoria is the clinical symptom that typically

3:51

presents in the infant with retinoblastoma and

3:55

has a large differential diagnosis.

3:58

However, none of these entities will usually cause calcification.

4:04

The only other entity that can cause calcification

4:07

and is a tumor affecting the globe is the medulloepithelioma.

4:11

However, this tumor typically involves the

4:17

anterior segment and the uvea,

4:23

as you recall, consists of the ciliary apparatus,

4:27

the iris, and the choroid.

4:33

Retinoblastoma is the most common cause

4:36

of leukocoria in childhood.