Congenital Lesions of the Pediatric Head and Neck - HD

Congenital Lesions of the Pediatric Head and Neck

Hello, I'm Harriet Paul Thiel from Boston Children's Hospital, and I'm going to talk to you about congenital lesions of the pediatric head and neck.

I have no disclosures.

There are many congenital lesions of the pediatric head and neck, including vascular anomalies, both tumors and malformations, disorders of the thyroid gland that include dysgenesis and thyroglossal duct cyst, other non thyroidal cystic lesions, atopic thymus and cervical extension of the normal thymus fibromatosis coli and aggressive fibromatosis or desmoid tumors and other nonvascular tumors, both benign and malignant.

Vascular Anomalies

Nowadays, most people who are involved in the imaging of vascular anomalies use the International Society for the Study of vascular anomalies, or ISSVA classification that divides the anomalies into tumors and malformations.

Vascular tumors are characterized by endothelial hyperplasia, and include hemangioma and less common tumors, whereas the malformations are characterized by vascular dysmorphia genesis that demonstrate a normal endothelial cell turnover.

Vascular Tumors

What I will discuss with you today is few of the most common tumors hemangioma, both congenital and infantile forms, and kaposiform hemangioendothelioma or KHE.

Infantile hemangioma is the most common tumor of infancy with a perinatal incidence of one to 2.6%.

Approximately 4% of all Caucasian infants are affected in the first year of life with a lower incidence in darker skinned infants.

The female to male ratio varies between three and five to one.

There is an increased incidence in preterm infants weighing less than a thousand grams up to 30%.

In fact, there is no clear genetic predisposition, but several risk factors have been identified, including advanced maternal age placental abnormalities and multiple gestations.

30 to 50% of infantile hemangiomas are present at birth, and they may be cutaneous or subcutaneous.

The cutaneous lesions permeate the dermis, and as you can see here, the skin is raised, ated and crimson in color in the lower dermis, subcutaneous, or muscle, often present as raised bluish lesions with indistinct margins at about two to three months of age or later.

Here's an infantile hemangioma documented by ultrasound.

We see a hypoechoic lobulated mass that's very vascular with color doppler, and contains a prominent arterial flow on spectral analysis.

The majority of them are located in the head and neck region, with about a quarter on the trunk and the remainder on the extremities.

The increased risk of complications and need for treatment are correlated with size.

About 80% of hemangiomas are solitary and are GLUT1 positive.

On pathological staining, infants with multifocal lesions are more likely to have GI tract involvement, and they may have bleeding and anemia and greater than five skin lesions is an association with increased risk of hepatic hemangioma and patients may present between one and 16 weeks of age postnatally with hepatomegaly, congestive heart failure, anemia, or asymptomatic masses.

Here's a child with bilateral parotid swelling.

You can see that there's involvement of the skin and then this subcutaneous bluish discoloration.

The left and right parotid glands are markedly enlarged and largely replaced by the hypoechoic lobulated hemangiomas tissue.

Here is the color Doppler appearance of one of these lesions with prominent arterial flow and also venous flow as well.

And sometimes we can see arterial venous shunting by color doppler presumably due to micro fistula within the tumor.

Here's a typical MR appearance, homogeneous lobulated masses on T two weighting prominent vessels, flow voids with homogeneous enhancement after gadolinium administration.

Here's a patient with an ulcerated hemangioma, involvement of the skin and a very large lobulated, here, a somewhat heterogeneous mass by ultrasound with prominent vascularity.

These hemangiomas undergo a very well-defined clinical course.

The proliferative phase involves rapid growth during the first six to 12 months of life, followed by an involuting phase with slow regression over one to seven years, where the endothelial matrix is replaced by loose fibrous or fibro fatty tissue.

And finally, the involuted phase and about half of the patients the skin is almost normal, whereas in the remainder there may be laxity, yellowish discoloration, and scarring.

You'll notice in this child who had a very large hemangioma that involved the eye and has an abnormal inward gaze here, and these patients can develop amblyopia if they're not treated and this has to be looked out for.

Congenital hemangiomas are relatively uncommon.

They evolve in utero and they're fully grown at birth, and they may be detected prenatally as early as the 12th week of gestation.

They're usually solitary.

Unlike the infantile hemangiomas, they are GLUT1 negative on pathologic staining, and there appear to be two types based on their postnatal behavior, the so-called RICH or rapidly involuting congenital hemangioma and the NICH, the non involuting congenital hemangioma.

Here's a patient with an in-utero diagnosis of a large scalp mass.

We see there's some central necrosis, very vascular lesion with color and spectral doppler containing prominent pulsatile venous flow and arterial flow.

The patient also had an in utero MRI and here's the patient at birth.

The lesion is fully grown, and by MRI, we see a homogeneously enhancing mass with prominent central vasculature.

These patients may have associated malformations.

There's the so-called PHACES syndrome where the P stands for posterior fossa and other structural brain anomalies, H for hemangiomas of the cervical facial region, as we see here, A for arterial cerebral vascular anomalies, C for cardiac defects, aortic coarctation, and other aortic abnormalities.

E for eye anomalies and S for sternal defects and or supra umbilical.

There is a risk for stroke in these patients, and they should undergo MRI to assess the brain and cerebral vasculature, and also should undergo ophthalmologic endocrine and cardiac evaluation to rule out associated anomalies.

Patients with lumbosacral hemangiomas may have occult spinal dysraphism, including tethered cord and lipomeningocele.

Those with pelvic and perineal hemangiomas may have urogenital and anal rectal anomalies.

Here's a patient with a PHACES syndrome.

You see the hemangioma involving the skin and subcutaneous tissues of the face here, thickening prominent vessels.

There is absence of the vermis a very small cerebellar hemisphere, very prominent retro cerebellar fluid collection.

The carotid artery is small on this side.

There's prominent cortical veins and an ectatic basilar artery in this patient.

Here's a patient with a very prominent lumbosacral hemangioma.

Here we see a spinal ultrasound examination with prominent vessels in the spinal canal.

This was shown very well with color and spectral doppler.

And you'll notice that there's asymmetry of the kidneys.

There's a very small left kidney, and the patient went on to have an MRI.

Here we see some prominent vessels superficially on this transverse view.

We see them in the buttock region after gadolinium and the prominent intraspinal vessels on these MR images.

And there's actually even a tiny liver hemangioma.

Three and a half years later.

These vessels have regressed as the hemangiomas do undergo involution, as we've already discussed, and we can't see them any longer by MRI.

Most hemangiomas are small and regress without treatment.

It's important to refer these patients to a specialty center in the event of an equivocal diagnosis, a dangerous location as near the eye.

They're large, if they're very large in size, if they grow rapidly, or if there are potentials for other complications, such as skin ulceration, or congestive heart failure.

Hypothyroidism, abdominal compartment syndrome, which can occur with hepatic hemangiomas.

I'd like to now discuss kaposiform hemangioendothelioma.

60% of these present in the neonatal period with 93% presenting in infancy.

They're usually unifocal and present with an enlarging cutaneous lesion in three quarters.

Thrombocytopenia in just over half and musculoskeletal pain or decreased function in about a quarter.

They may affect the trunk, the shoulder, the thigh, or the retroperitoneum, and there's a spectrum of clinical behavior and pathological findings.

They may be locally aggressive, or they may be slow growing and benign, the so-called tufted hemangioma.

And here we have a couple of pathological slides.

Here's a patient with kaposiform hemangioendothelioma of the anterior abdominal wall.

We see it here on the ultrasound image.

Has a very different appearance from the typical infantile or congenital hemangiomas that I showed you earlier.

But prominent arterial and venous flow.

And here we see it by MRI, it on T one.

You see the flow voids here, some increased signal on inversion recovery and a mild degree of enhancement after gadolinium.

Vascular Malformations

Onto a discussion of vascular malformations.

These are localized or diffuse errors of embryonic development that affect about 1.2 to 1.5% of the population.

Most are sporadic, some are inherited and may affect any segment of the vascular tree, including the arteries, capillaries, venous, and lymphatic vessels.

They're categorized according to the predominant channel abnormality and flow characteristics.

Slow flow anomalies include capillary venous and lymphatic malformations, fast flow anomalies, arteriovenous malformations and fistulas.

There may be complex combined vascular malformations, and these do not undergo spontaneous regression.

Venous malformations are the most common vascular anomaly, with an incidence of one to two per 10,000 births and about a 1% prevalence.

They can be found throughout the body with about 40% occurring in the head and neck region.

95% of them are sporadic.

However, the TIE2 mutation has been identified in some hereditary cutaneous mucosal malformations.

The Glomu venous malformation being the most common.

Most of the venous malformations are solitary and range from a small, superficial and well circumscribed lesions to large infiltrating lesions that involve multiple soft tissue planes.

They're usually isolated, but some are associated with syndromes.

Here's a patient with a large venous malformation involving the floor of the mouth and the jaw.

You can see here by ultrasound that it consists of multiple vascular channels of different sizes, very prominent flow with color and venous waveforms identified with spectral analysis.

Here is an MRI showing the very extensive malformation and ultrasound was also used to access the malformation during sclerotherapy, which we see below.

Lymphatic malformations may be localized or diffuse.

They consist of dilated channels filled with proteinaceous fluid that are generally not connected to the normal lymphatic system.

They may be macrocystic, meaning that they're larger than one centimeter in diameter, microcystic or combined.

They may be diagnosed prenatally at birth or in early childhood.

About 48% of them occur in the head and neck region with the remainder in the trunk and extremities, in the thorax, and in the abdomen.

They grow with the child and may enlarge rapidly after hemorrhage or infection.

Here is a prenatal ultrasound scan of a patient with a large lymphatic malformation here.

See it coming off the skull.

Here's the trachea with part of the malformation, just enveloping it.

And here is just an high resolution image showing the channels of varying size.

MRI images, again, show how extensive this lesion is.

Here it is surrounding the trachea and we see it here at birth with some prominent bulges in the neck.

And again, cystic spaces of varying size.

Sono graphically.

Here is another patient with an enormous lymphatic malformation, very distorting.

You see that the patient is intubated, again, cystic spaces of varying size, some fluid, fluid levels because these lesions may hemorrhage.

Here you see again, the marked distortion of the cervical spine and the enormous malformation with some susceptibility artifact and fluid, fluid levels related to hemorrhage.

And the typical enhancement of the septations of the lesion after gadolinium administration.

Arteriovenous malformations consist of a direct communication between dysplastic arteries and veins without an intervening capillary bed.

The shunt is the nidus of the AVM, and these lesions have high flow physiology.

Most are sporadic, although heritable forms have been identified and about 40% are identified at birth.

Their behavior is unpredictable.

Most are dormant in infancy and childhood and enlarged during adolescence or following trauma or surgery, and they may exert a mass effect.

They may cause soft tissue destruction and bone erosion.

I've listed here some important complex combined malformations that include AVMs and other some of the other vascular anomalies, the Klippel-Trenaunay syndrome, which may be due to somatic mutations in the PI3KCA gene.

These patients have capillary lymphatic venous malformations with soft tissue and skeletal hypertrophy of the limbs and or trunk.

The CLOVES syndrome patient.

It's due to somatic mutations in the PI3KCA gene patients present with congenital lipomas overgrowth, vascular malformations, epidermal nevi, scoliosis, and skeletal and spinal anomalies, and the Parkes Weber syndrome, which is sporadic or inherited, where they have large cutaneous capillary malformations on the extremities, multiple micro AV fistulas and limb overgrowth.

And then finally, the capillary malformation arteriovenous malformation syndrome, or CM-AVM due to germline mutations in the RASA1 gene, where the patients have capillary malformations and high flow lesions, including AVMs, AV fistulas, and Parkes Weber syndrome.

So here's a patient with CLOVES syndrome diagnosed in utero.

We see this kind of delta shaped foot.

There's a gap which we'll see better postnatally between some of the toes.

There's truncal lymphatic malformations.

And here's the child at birth, a very high forehead, capillary malformations on the trunk and hands, I'll just go back here.

And a wide spacing between the digits, as you can see here in the hands and in the foot.

And here we see some of the typical MR features.

There's some scoliosis, truncal vascular anomalies.

Here we see lymphatic malformation with septal enhancement.

Here's a patient with CM-AVM.

You can see there's capillary malformations on the face and limbs and perineum.

And there's abnormal bones in the forearm.

Notice that they're deformed and sclerotic, and that's because of the presence of vascular malformation and a AVM in the forearm we see the vessels here, no mass high flow arterial wave forms.

And an MRA examination was done here, and we can see that there's an arteriovenous malformation in that arm with rapid venous drainage.

And after gadolinium administration, we see some abnormal enhancement of the musculature of that arm.

Thyroid Disorders

I'd now like to move on to a discussion of thyroid disorders, including dysgenesis, which may consist of hypoplasia or aplasia and thyroglossal duct cyst.

Congenital hypothyroidism is present in one per 4,000 infants.

It's twice as common in girls as in boys, and about 85% of cases are due to dysgenesis.

Ultrasound is very helpful in depicting thyroid size, which may be large, normal, small or absent, thyroid hemi agenesis, which is quite rare, or ectopic tissue, which is lingual in about 90% of cases.

So here's one example of a neonate with congenital hypothyroidism in the region of the thyroid bed, there's no thyroid gland, but lower down in the submental region, we see this tissue that looks similar to an echogenicity to what we would expect to see with a normal thyroid.

And this did indeed end up being a patient who had ectopic thyroid tissue.

The thyroglossal duct cyst comprises about 70% of all congenital neck masses and arises from remnants of the embryonic thyroglossal duct, which connects the foramen cecum at the tongue base to the thyroid gland secretions produced by the epithelial lining of the cyst cause enlargement.

And about 65% of these are infrahyoid, 20% suprahyoid, and 15% are located at the level of the hyoid bone.

And on clinical examination, these patients will have a midline or slightly off midline mass that moves with swallowing.

These cysts may contain ectopic thyroid tissue, and they're resected because of the risk of infection and malignancy, mainly papillary carcinoma.

And here we see a typical cystic mass.

We have some typical colloid artifacts with this ring down artifact that you see here.

And this is a clip scanning from superior to inferior in this patient who also has a normal looking thyroid gland, as we can see here.

And the patient did have an MRI, which shows the cyst, although I think the ultrasound shows the internal architecture better.

Other Cystic Lesions

Other cystic lesions of the neck include branchial cleft cyst, dermoids or epidermoids.

And I mentioned duplication cyst and bronchogenic cyst because they can occur, but they're quite rare.

And I won't discuss 'em further.

The embryological branchial apparatus consists of six paired mesodermal arches that are separated externally by five ectodermal lined branchial clefts, and internally by five endodermal lined pouches during development.

The first and second arches grow caudally and cover the third and fourth arches and their clefts.

And this cervical sinus is eventually obliterated.

The branchial cysts, sinuses, and fistulas develop when there's a failure of obliteration of the cervical sinus or of the first and second branchial cleft or pouch.

90% of all branchial abnormalities arise from the second branchial cleft, 8% from the first and the remainder from the third.

Branchial cleft cysts are the most common abnormality.

The second branchial cleft cyst is located in the lateral aspect of the anterior triangle of the neck and presents as a non-tender mass in the upper neck.

It may be bilateral.

There's no communication with the skin or pharynx, and these cysts are avascular unless they become infected, and where they may develop peripheral hyperemia and first branchial cleft cysts are located in and around the parotid gland.

Here's an example of a patient with a branchial cleft cyst.

We see a normal thyroid, and then here in the left neck we see a cystic structure with some surrounding hyperemia, some central debris.

In this patient who had an infected branchial cleft cyst, dermoid cyst contain two germ cell layers, the dermis and mesoderm, whereas the epidermoid cyst contains a single germ layer.

The ectoderm most occur adjacent to the orbit or the nose.

About 11% are located in the floor of the mouth in the submandibular space, and these lesions present as a painless midline mass.

Here is a child with a scalp cyst.

The dermoids in the epidermoids essentially have the same imaging appearance, well-defined iso or hypoechoic lesion adjacent to the soft tissues we see here.

They may contain keratin or sebaceous debris.

Neuro calcifications may be present.

Scalp lesions are painless, mobile rubbery masses that may slowly enlarge.

And it's important to determine whether the lesions that do involve the skull to determine whether or not they penetrate the brain.

And that's why this MRI examination is done.

And we can see that this particular lesion does not.

Ectopic Thymus and Cervical Extension of Normal Thymus

Ectopic thymus may result from failure of complete descent of the embryonic thymus into the mediastinum and presents as a midline or lateral neck mass.

Most patients are asymptomatic and the ectopic thymus usually extends inter medial to the carotid sheath and demonstrates no connection with the mediastinal thymic tissue.

So here we have a patient who has this nodule, which looks very similar to normal thymus except that it's in an abnormal location here.

We see it in the right neck on a transverse view.

And here's a normal thymic gland where you can also see this echogenic appearance.

The normal mediastinal thymus can intermittently herniate into the neck where the thymic tissue may lie above the level of the left brachiocephalic vein.

And the normal thymus can present as a midline or lateral neck mass that demonstrates anatomical continuity with the mediastinal thymus.

And here we can see this intermittent herniation, if you watch here, it herniates up into the neck.

Here we see it on sagittal view, a not uncommon mass that we see in pediatric imaging.

Fibromatosis Colli and Aggressive Fibromatosis

Fibromatosis colli is a benign lesion that results from co contracture of the sternocleidomastoid muscle.

The patients present soon after birth with torticollis or wry neck and a painless firm mass with the majority being right sided.

These usually regress with conservative therapy over four to eight months.

So here we see there's little asymmetry of the soft tissues here of the right neck.

And here you see the large sternocleidomastoid compared to the normal muscle on the left side.

Aggressive fibromatosis or desmoid tumor is a locally aggressive but histologically benign lesion that consists of fibrous tissue proliferation with an invasive growth pattern and a tendency to recur locally.

These lesions do not spread to distant locations, and they usually occur after puberty, but have been reported in infants and children.

Most cases are sporadic.

There is an association with familial adenomatous polyposis and is seen also in about 10% of individuals who have Gardner syndrome.

Here's a patient who had a cervical desmoid tumor, which we see very well on CT imaging of ultrasound was used during the time of biopsy.

Here we see the biopsy needle entering the mass.

It has a somewhat heterogeneous appearance.

Other Nonvascular Tumors

Finally, a few words about other nonvascular tumors that may occur in the head and neck region.

Teratoma benign tumor or malignant fibrous sarcoma, rhabdomyosarcoma and neuroblastoma.

Cervical teratoma is rare.

It occurs in about one in 40,000 live births and represents about five to 14% of all neonatal teratomas.

It arises from pluripotent cells of two or three germ layers, and about 90% of childhood teratomas contain all three germ layers with variable differentiation.

About 75 to 85% of head and neck tumors will contain neuroectodermal tissue, and most cervical teratomas are benign.

They usually present as a large infiltrative, cystic, and solid lesion.

In the anterolateral aspect of the neck, airway impingement is the most common cause of morbidity and prenatal identification aids and management at delivery.

And there's a near 100% mortality if these tumors are not immediately managed.

And by managed, I mean that the airway is maintained and they need to be resected.

So here's a neonate who was born via the EXIT procedure.

We see a very large mass.

Here is a catheter in the esophagus.

It was arising from the left thyroid lobe.

Here we see a coronal view.

This is the right thyroid lobe, very vascular mass.

Here we see it on a coronal MR sagittal.

It's going kind of fast, but it was arising from the left thyroid lobe.

And finally, a few words about neuroblastoma.

This is a malignancy of cells derived from the neural crest, which may present with cutaneous metastases, which are common and are seen as a presenting feature.

In about 30% of cases, the patients may have periocular ecchymosis that cause raccoon eyes.

As you can see here, here's a cutaneous metastasis.

And in this patient, there is involvement of the scalp.

And here we see the underlying scalp.

We see these round lobulated masses with flow by color doppler.

Here we have a couple of clips of CT scan, again showing these masses down at the skull base.

And here's a coronal view.

Here we see masses.

Summary

So in summary, I've reviewed with you some of the most common congenital lesions of the pediatric head and neck, including vascular anomalies, thyroid disorders, other cystic lesions, ectopic thymus, cervical extension of normal thymus, teratoma, and neuroblastoma.

Thank you.