Approach to leukocoria (pediatrics): Clinical sciences

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Introduction0:00–0:36

Leukocoria refers to a white or pale pupillary reflex and its presence suggests a structural abnormality within the visual axis.
It's important to identify underlying causes of Leukokoria promptly. Since these conditions can either be lethal or lead to profound visual impairment.
If left untreated, a thorough ophthalmologic exam can distinguish intraocular masses from other abnormalities involving the lens retina or vitreous.

History and physical0:36–2:50

When a pediatric patient presents with leukocoria first perform a focused history and physical examination including vision screening and direct ophthalmoscopy.
Now, here's a clinical pearl to keep in mind, you can look for Leukokoria by checking your patient's red reflex to do so dim the lights to ensure the pupils are dilated, then look through an ophthalmoscope while standing approximately 2 ft away from your patient view each eye separately and both eyes together.
During this test, light from the ophthalmoscope normally reflects back from the illuminated retina producing a reddish orange glow, a bilateral red reflex suggests the absence of structural pathology within the visual axis, but a white pale or absent reflex requires further examination.
Now, back to our patient history often reveals visual changes and in some cases, there's a family history of retinoblastoma during vision screening, you may identify vision loss and the exam will reveal a unilateral or bilateral white pupillary reflex.
This confirms leukocoria. So to find out what's causing it, refer your patient urgently for a complete ophthalmologic exam, including a dilated funduscopic exam with indirect ophthalmoscopy and a slit lamp exam.
Keep in mind that patients who cannot tolerate an office evaluation may require an exam under anesthesia. Here's a clinical pearl.
Although a white reflex raises concern for serious pathology, it can also represent a benign transient finding called pseudo Leukokoria.
Often seen as a flash photograph with direct ophthalmoscopy or in Children with asymmetric refraction. It can be difficult to distinguish pseudo leukokoria from true Leukokoria.
So it's best to follow up with a complete ophthalmologic evaluation. Now, whenever a child presents with Leukokoria, the first thing to think of is retinoblastoma.

Retinoblastoma2:50–5:26

So immediately assess for an intraocular mass retinoblastoma is the most common ocular tumor in Children. But the exam alone can't always distinguish this tumor from other intraocular masses like a granuloma caused by ocular larva migrans.
This is a manifestation of toxocariasis which occurs when a patient ingests the eggs of the roundworm, toxicara canis or toxicara CTI which are shed in dog and cat feces and can be found in the soil.
As the ingested eggs mature into larva, they travel to various organs including the eye. So if a mass is identified, your patient should be assessed for exposure to cats or dogs.
And for a history of a type of pika called geophagia or eating dirt. Since this increases the risk of toxocariasis and subsequent ocular larva migrans.
If there's no known exposure, consider retinoblastoma. These patients are typically under five years of age and most are younger than three history.
May also reveal strabismus, visual changes or a family history of retinoblastoma. Vision screening may demonstrate decreased visual acuity.
Ocular findings could be either unilateral or bilateral and may include orbital inflammation, blood in the anterior chamber, retinal detachment or vitreous inflammation.
Often one or more whitish gray or cream colored retinal masses will be seen. These findings are highly suggestive of retinoblastoma.
So an orbital ultrasound or MRI is needed for confirmation. Imaging will demonstrate an intraocular mass with calcifications, possibly with extraocular spread or optic nerve involvement.
These findings confirm retinoblastoma. Ok.
Here's your first high yield fact, retinoblastoma occurs when the tumor suppressor gene R B1 is altered either sporadically or through a germline mutation compared to Children with sporadic retinoblastoma.
Those with hereditary retinoblastoma are more likely to be diagnosed earlier, have bilateral disease and develop secondary malignancies such as sarcoma or melanoma.
Now, on the other hand, if your patient does have a known exposure to cats or dogs, consider ocular larva migrans caused by toxocariasis, affected.

Ocular larva migrans5:26–6:49

Patients are usually young Children with a cat or dog in the home and they may frequently play in a sandbox. Occasionally history reveals pika.
Some patients report visual changes, eye pain, redness or new onset strabismus. Physical exam typically reveals unilateral eye involvement.
Vision screening may show decreased visual acuity and fundoscopy may demonstrate tractional retinal detachment. If the patient has visceral larva migrans with other organ involvement such as hepatitis or pneumonitis.
They might also have skin lesions or signs suggesting systemic disease like fever, wheezing or hepatomegaly. Continued workup includes an orbital ultrasound or RIA CBC and a toxicara serology.
The imaging will show a subretinal thickening or nodule without calcifications. Labs might demonstrate eosinophilia or positive toxicara serology.
These findings confirm a diagnosis of ocular larva migrans, also known as ocular toxicariasis or larval granulomatosis. Ok.

Cataract6:49–8:21

Let's switch gears and move on to patients without an intraocular mass. Here, you should assess for a lens opacity and if present consider a cataract.
These patients frequently present with visual inattentiveness and sometimes nystagmus. Additionally, history may reveal an underlying condition such as prematurity, a genetic or metabolic disorder or a congenital infection.
Older Children might report trauma or chronic corticosteroid use a unilateral or bilateral lens opacity establishes the diagnosis of a cataract.
Here's a high yield fact, various conditions are associated with cataract formation including galactosemia, galactokinase deficiency, trisomy 1318 and 21 and Turner syndrome as well as congenital infections like toxoplasmosis, cytomegalovirus, syphilis, rubella, herpes simplex and varicella zoster virus.
Let's follow that up with a clinical pearl. Another cause of lens opacity is persistent fetal vasculature which occurs when persistent fetal blood vessels and fibrous tissue cloud the lens, unlike cataracts, this condition is usually found in otherwise healthy infants and is typically unilateral and associated with microphthalmia.
Now, let's move on to patients without lens opacity. At this point, you'll need to refer your patient to the ophthalmology team for a dilated eye examination to assess for retinal detachment.

Retinal detachment8:21–8:48

Because retinal detachment is almost always related to trauma or another condition, you'll need to look for an underlying cause.
Once the retinal detachment is confirmed, assess your patient's gestational age at delivery. If they were born, preterm, consider retinopathy of prematurity or rop history is likely to reveal a gestational age less than 32 weeks at delivery with low birth weight.

Retinopathy of prematurity8:48–9:33

These patients often have complications of prematurity like prolonged mechanical ventilation and hyperoxygenation. The exam typically demonstrates a bilateral symmetric white reflex.
While fundoscopy reveals a cloudy vitreous neovascularization of the retina and fibrous proliferation behind the lens. These findings support a diagnosis of rop the most common cause of severe visual impairment in Children.

Coats disease9:33–10:40

Now, let's discuss retinal detachment in patients who were born full term in this case, consider coats disease a disorder characterized by retinal te ectasias and subretinal exudates.
Most patients are previously healthy biological males who present after the first year of life history might reveal blurred vision and strabismus.
The exam typically reveals a yellowish reflex. While fundoscopy demonstrates retinal telangiectasias, subretinal lipid deposition, intraretinal and subretinal exudates and retinal hemorrhage with these findings, you can confirm a diagnosis of coats disease, also known as exudative retinopathy.
Here's another clinical pearl retinal dysplasia is another cause of leukocoria and retinal detachment. Usually it's part of a genetic condition such as Trisomy 13 Norrie disease, familial exudative vitreal retinopathy or incontinentia pigmenti.

Coloboma10:40–11:46

Ok. Let's look at patients without retinal detachment.
Here, you should assess for blood in the vitreous if no blood is present, consider coloboma. This congenital defect is caused by incomplete formation of the structures around or within the eye.
A coloboma of the retina or optic nerve often presents with visual deficits. While coloboma can be an isolated finding, it's often associated with genetic conditions such as Trisomy 13 or 18.
It can also present as a manifestation of charge syndrome, which stands for Coloboma heart anomalies, choanal atresia, restricted growth and mental development, genital hypoplasia and ear anomalies.
The exam will demonstrate either unilateral or bilateral eye involvement and findings could include peripheral visual field deficits, a wedge shaped retinal defect and in some cases, microphthalmus with these findings diagnose coloboma.

Vitreous hemorrhage11:46–12:27

Finally, if there's blood in the vitreous, consider a vitreous hemorrhage, these patients might have a history of trauma or an underlying condition associated with thrombocytopenia or coagulopathy, visualization of blood in the vitreous is enough to diagnose vitreous hemorrhage, but you may also detect red or white debris in the vitreous which further supports the diagnosis.
Here's one last clinical pearl. Whenever you see vitreous hemorrhage retinal hemorrhage or detachment or retinoschisis in a child under two years of age.
Be sure to evaluate for non accidental head trauma. All right, as a quick recap when a pediatric patient presents with leukocoria, refer your patient urgently for a dilated funduscopic and slit lamp exam.

Review12:27–13:12

First look for an intraocular mask to rule out retinoblastoma and assess for exposure to cats or dogs to rule out ocular larva migrans.
If you don't identify an intraocular mass, look for a lens opacity which indicates a cataract. Otherwise, retinal detachment can occur in patients with retinopathy of prematurity or coats disease.
Finally, a wedge shaped retinal defect suggests coloboma and the presence of vitreal blood indicates a vitreous hemorrhage.