Because the auricle develops from tissues of the branchial arches, it is not surprising that a significant percentage of microtic patients exhibit deficient facial components which originate from these embryological building blocks. Appearing as a flattened side of the face, this condition is known as hemifacial microsomia, and is basically an underdevelopment of the bony jaws and overlying soft tissues (see Fig. 3). The most complete genetic expression of this condition includes defects of the external and middle ear; hypoplasia of the mandible, maxilla, zygomatic, and temporal bones; macrostomia and lateral facial clefts; paresis of the facial nerve; and atrophy of facial muscles and parotid gland [67, 68, 70]; even the palatal muscles are weak on the involved side .
Fig. 3 - Patient with hemifacial microsomia.
|This condition is present to some degree in about one third of microtia patients, and consists of obvious bony and/or soft tissue deficiencies which make the side of the face appear flattened or distorted.|
In analyzing my own series of 1,000 microtia patients, I found that associated branchial arch deformities were common: 36.5 percent of my patients had obvious bony and/or soft tissue deficiencies, making the side of the face appear flattened or distorted. Of these, the family perceived the facial deformity as "'significant" in 49.4 percent of the cases. This obvious facial asymmetry is usually dealt with after the auricle is repaired . From my years of long-term observation of a multitude of patients, this asymmetry doesn't seem to worsen as the child grows, but instead grows proportionally in its relation with existing facial features. This has been borne out by a recent growth analysis investigation .
Overt facial nerve weakness was found in 15.2 percent of my 1,000 microtia patients, causing a weak smile or inability to close one eye completely. Of these, 42.6 percent had involvement of more than one nerve branch (see Table 2).
Table 2 - Associated Deformities
Author's Series of 1,000 Microtia Patients
|Branchial Arch Deformities|
|A. Obvious Bony and Soft Tissue Deficit
|Family perceives it as "significant"||49.4 %|
|B. Overt Facial Nerve Weakness||15.2 %|
|Of these, more than one branch involved||42.6 %|
|Cleft Lip and/or Palate||4.3 %|
|Urogenital Defects||4.0 %|
|Cardiovascular Malformations||2.5 %|
|Misc. Deformities||1.7 %|
Urogenital tract abnormalities increase in the presence of auricular deformities , particularly when the patient is afflicted with other manifestations of facial underdevelopment . Several of my patients have hypospadius or vaginal agenesis, and four percent have proven abnormalities of their collection systems, which include horseshoe kidney, ureteral duplication, unilateral renal agenesis and pelvic kidney. However, because the body has enough "reserve" to easily live with just one kidney, I have yet to see any microtia patient suffer any life-threatening renal consequences from these system abnormalities. A routine screening of the urine may detect silent hematuria or proteinuria, but as likely will show nothing. Recurring urinary tract infections in microtia patients prompt renal function studies, and one should start with a renal ultrasound before considering more invasive technique to detect these deformities. Because of the increased incidence of urogenital abnormalities in microtia patients, one might consider screening all of them with ultrasound.
Cervical spine anomalies are more common in microtic patients if other "midline defects" exist, such as cardiac or renal disorders or cleft lip and palate. Because associated neurologic symptoms are rare, the frequency of these vertebral abnormalities are probably underestimated in patients with microtia. Goldenhar Syndrome (oculoauriculovertebral dysplasia) is a condition in which the microtia patient has an ocular dermoid (tissue growth on the eye; see Fig. 4) and usually has cervical vertebral abnormalities . When one notes an ocular dermoid or detects limited range of neck motion in any microtia patient, one should investigate the renal function and evaluate the cervical spine as well. Regarding the latter, CAT scans will provide useful information for any physician caring for these patients . It is particularly wise to bring this condition to the anesthesiologist's attention during any kind of surgery, so that unusual neck manipulation is avoided during induction of anesthesia; and the child's head should not be forcibly turned, but instead, the head, neck, and body should be "log-rolled" as a unit for any turning maneuvers during surgery.
If there is any suspicion of neurological disturbances seen in these children, they should undergo CT scan, MRI, and appropriate neurologic examination .
Fig. 4 - An ocular dermoid.
|When a patient has microtia, and one notes such a tissue growth on the eye, then one should investigate for abnormalities of the spine in the neck as well. These three defects (ear, eye, and cervical spine) constitute Goldenhar Syndrome.|
Cleft lip and/or palate is seen in 4.3 percent of my patients, and 2.5 percent have cardiovascular malformations. The latter have included atrial and ventricular septal heart defects, dextrocardia, transposition of the great vessels, three-chambered heart, and patent ductus. If any signs or symptoms of these heart problems are noted, the pediatrician should consult with a cardiologist for appropriate steps in management.