Inservice Exam - 2005
Cranio-Facial

.Which of the following craniofacial anomalies is associated with orbital hypotelorism?

(A) Crouzon syndrome
(B) Frontonasal dysplasia
(C) Frontonasal encephalocele
(D) Trigonocephaly


The correct response is Option D.

Hypotelorism, a decrease in intraorbital distance, occurs with trigonocephaly caused by metopic synostosis and holoprosencephaly. In patients with metopic synostosis, growth is inhibited perpendicular to the synostotic metopic suture, resulting in decreased interorbital distance as well as narrowing of the forehead. Holoprosencephaly results from a breakdown in the formation of prechordal mesoderm, leading to deficiencies of the structures located in the midline and narrowing of interorbital distance.

Hypertelorism, an increase in interorbital distance, is associated with numerous craniofacial disorders, including frontonasal encephalocele and median facial clefts occurring secondary to incomplete fusion of the medial orbital walls. Patients with more severe forms of craniosynostosis, such as Apert or Crouzon syndrome, may also have orbital hypertelorism. The hypertelorism seen in patients with frontonasal dysplasia occurs as a result of excess bone formation.


References:
1. Kawamoto HK. Craniofacial clefts. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith’s Plastic Surgery. 5th ed. Philadelphia: Lippincott Williams & Wilkins;1997:349-363.
2. Ortiz-Monasterio F, Molina F. Orbital hypertelorism. Clin Plast Surg. 1994;21:599-612.
3. Tessier P. Anatomical classification of facial, craniofacial and latero-facial clefts. J Maxillofac Surg. 1969;4:69.




In patients with Binder syndrome, the most likely physical finding is hypoplasia of which of the following structures?

(A) Anterior cranial base
(B) Anterior nasal floor
(C) Anterior wall of the maxilla
(D) Medial orbital wall
(E) Nasal septum

The correct response is Option B.

A patient with Binder syndrome, or maxillonasal dysplasia, typically has a shortened nose with flattening of the nasal bridge and perialar regions. The columella is shortened, the nasolabial angle is acute, and the upper lip is convex. The anterior nasal spine and frontonasal angle are absent. Occlusion is Angle class III. Binder syndrome is caused by hypoplasia of the anterior nasal floor (fossa praenasalis) and localized symmetric maxillary hypoplasia in the region of the alar rims. Nasal views show a retracted columellar-lip junction, a perpendicular alar-cheek junction, a convex upper nasal tip with a wide, shallow philtrum, crescent-shaped nostrils without a sill, a low-set and flat nasal tip, and a stretched and shallowed cupid’s bow. The triangular flair typically seen at the base of the nose is instead absent.

In patients with Binder syndrome, the primary goal of surgery is increasing the length of the nose and the projection of the nasal tip. This can be achieved by performing Le Fort I osteotomy, Le Fort II osteotomy, or a combination of both procedures, as well as compensatory orthodontic treatment. Autogenous bone and cartilage grafts may be required to reconstruct the nose.


References:
1. Holmstrom H. Clinical and pathologic features of maxillonasal dysplasia (Binder’s syndrome): significance of prenasal fossa on etiology. Plast Reconstr Surg. 1986;78:559-567.
2. Posnick JC, Tompson B. Binder syndrome: staging of reconstruction and skeletal stability and relapse patterns after Le Fort I osteotomy using miniplate fixation. Plast Reconstr Surg. 1997;99:961-973.




Mutation of the fibroblast growth factor receptor (FGFR) has been most commonly associated with which of the following single-suture synostoses?

(A) Lambdoid
(B) Metopic
(C) Sagittal
(D) Squamosal
(E) Unicoronal


The correct response is Option E.

Mutation of FGFR3, located at chromosome 4p16, has been found to cause unicoronal synostosis. This suggests a genetic basis for certain forms of synostotic frontal plagiocephaly. FGFRs regulate cell growth and bony proliferation. Mutations in FGFRs have been associated with syndromic craniosynostoses, such as in Pfeiffer, Crouzon, and Jackson-Weiss syndromes.

Evaluation of patients with unicoronal synostosis showed more severe cranial dysmorphology and a higher number of surgical revisions in those with FGFR3 mutation for facial dysmorphology compared with those without the mutation. This finding has led to genetic screening for all patients with unicoronal synostosis to better counsel patients and anticipate surgical outcomes.


References:
1. Cassileth LB, Bartlett SP, Glat PM, et al. Clinical characteristics of patients with unicoronal synostosis and mutations of fibroblast growth factor receptor 3: a preliminary report. Plast Reconstr Surg. 2001;108(7):1849-1854.
2. Gripp KW, Stolle CA, McDonald-McGinn DM, et al. Phenotype of the fibroblast growth factor receptor 2 Ser351Cys mutation: Pfeiffer syndrome type III. Am J Med Genet 1998;78(4):356-360.
3. Gripp KW, McDonald-McGinn DM, Gaudenz K, et al. Identification of a genetic cause for isolated unilateral coronal synostosis: a unique mutation in the fibroblast growth factor receptor 3. J Pediatr. 1998;132(4):714-716.




Which of the following findings is commonly caused by nonsyndromic unicoronal synostosis?

(A) Anterior displacement of the ipsilateral ear
(B) Deviation of the root of the nose to the contralateral side
(C) Flattening of the ipsilateral aspect of the occiput
(D) Occlusal cant up on the ipsilateral side
(E) Recession of the contralateral forehead


The correct response is Option A.


Nonsyndromic unicoronal synostosis commonly causes anterior displacement of the ipsilateral ear toward the affected suture. It also typically results in ipsilateral flattening and contralateral bossing of the forehead and deviation of the root of the nose to the ipsilateral side toward the affected suture. Unicoronal synostosis does not typically affect occlusion on either side and is not likely to cause significant change in occipital shape.


References:
1. Bruneteau RJ, Mulliken JB. Frontal plagiocephaly: synostotic, compensational, or deformational. Plast Reconstr Surg. 1991;89:21-31.
2. Biggs WS. Diagnosis and management of positional head deformity. Am Fam Physician. 2003;67:1953-1958.




A 2-month-old infant has a facial cleft extending from the upper lip through the nasal ala and into the medial canthal region. Which of the following is the most appropriate Tessier classification of this cleft?

(A) No. 1
(B) No. 2
(C) No. 3
(D) No. 4
(E) No. 5

The correct response is Option C.

As shown below, the most appropriate classification for this cleft is Tessier number 3 because this is the only classification in which the cleft involves the nasal ala and medial canthus. A cleft classified as number 0 involves the midline of the nose. A cleft classified as number 1 or 2 involves the nasal ala but is medial to the eye. A cleft classified as number 4 or 5 is lateral to the nose and typically involves the lower eyelid.






References:
1. Kawamoto HK. The kaleidoscopic world of rare craniofacial clefts: order out of chaos (Tessier Classification). Clin Plast Surg. 1976;3:529-572.
2. Hunt JA, Hobar PC. Common craniofacial anomalies: facial clefts and encephaloceles. Plast Reconstr Surg. 2003;112:606-616.



In patients with Treacher Collins syndrome, which of the following is a characteristic skeletal finding?

(A) Brachycephaly
(B) Hypertelorism
(C) Macrogenia
(D) Malar hypoplasia
(E) Preaxial polysyndactyly

The correct response is Option D.
The characteristic skeletal finding in patients with Treacher Collins syndrome is hypoplasia of the malar bones, which often occurs in conjunction with clefting through the zygomatic arches. Patients also have hypoplasia of the maxilla and mandible and antegonial notching of the angle of the mandible. Occlusion is Angle class II; there is an anterior open bite and clockwise rotation of the occlusal plane. Effects on the temporomandibular joint are varied.

Brachycephaly, macrogenia, preaxial polysyndactyly, and hypertelorism do not occur in patients with Treacher Collins syndrome.


References:
1. Marsh JL, Celin SE, Vannier MW, et al. The skeletal anatomy of mandibulofacial dysostosis (Treacher Collins syndrome). Plast Reconstr Surg. 1986;78:460.
2. Posnik JC. Treacher Collins syndrome. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith’s Plastic Surgery. 5th ed. Philadelphia: Lippincott Williams & Wilkins; 1997:313.







A 4-month-old infant has had a mass on the central nasal bridge (shown above) since birth. Physical examination shows a mass measuring 0.5 _ 1 cm that is soft and minimally mobile with a central pore. MRI of the head is shown above. Based on these clinical findings, which of the following is the most likely diagnosis?

(A) Dermoid cyst
(B) Encephalocele
(C) Glioma
(D) Lipoma
(E) Vascular malformation

The correct response is Option A.

This infant has a nasoglabellar dermoid cyst with an intracranial component, which requires transcranial and local excision.

In pediatric patients, orbitofacial dermoid cysts vary in presentation and location. They typically fall into three subgroups: brow region, orbital region, and nasoglabellar region. Most dermoid cysts are located in the lateral brow region. Typically, dermoid cysts in the brow and orbital regions do not have intracranial extension and can be excised locally. However, 10% to 45% of nasoglabellar dermoid cysts have sinus tracts and occasional intracranial extension. For dermoid cysts in this region, further studies with MRI or CT are recommended to exclude intracranial extension.

Recent reports have shown frontotemporal dermoid cysts with sinus tracts that have intracranial extension. If a sinus tract with extension is encountered during local excision, further radiographic evaluation is warranted. Frontotemporal dermoid cysts may represent a distinct entity from dermoid cysts in the brow region.

References:
1. Bartlett SP, Lin KY, Grossman R, Katowitz J. The surgical management of orbitofacial dermoids in the pediatric patient. Plast Reconstr Surg. 1993;91(7):1208-1215.
2. Lacey M, Gear AJ, Lee A. Temporal dermoids: three cases and a modified treatment algorithm. Ann Plast Surg. 2003;51(1):103-109.




For each patient with coronal synostosis, select the most likely diagnosis (ABD).

(A) Apert syndrome
(B) Crouzon syndrome
(C) Pfeiffer syndrome
(D) Saethre-Chotzen syndrome


46 A 1-year-old infant has midface hypoplasia and axial skeletal deformities; the digits are normal


47 A 10-year-old boy has generalized acne and symmetric complex syndactyly


The correct response for Item 46 is Option B and for Item 47 is Option A.

Each of the patients described above has acrocephalosyndactyly, or a syndrome of craniofacial dysostosis. Patients with these syndromes have been shown to have “gain in function” anomalies of the fibroblastic growth factor receptors.
The 1-year-old infant has Crouzon syndrome, or acrocephalosyndactyly type II. This condition is characterized by hypoplasia of the midface, exorbitism, and axial skeletal deformities. The fingers and toes are typically unaffected.

The 10-year-old boy has findings consistent with Apert syndrome, or acrocephalosyndactyly type I, including bilateral complex syndactyly of the hands and feet and generalized acne. Mental deficiencies are also common.

Characteristic findings in patients with Pfeiffer syndrome, also known as acrocephalosyndactyly type V, include simple syndactyly and large, broad thumbs and great toes.

Saethre-Chotzen syndrome is also known as acrocephalosyndactyly type III. Affected patients typically have a low frontal hairline with backward sloping of the forehead, low-set ears, beaking of the nose, and ptosis of the eyelids. Simple syndactyly may also be seen.


References:
1. Bartlett SP, Mackay GJ. Craniosynostosis syndromes. In: Aston SJ, Beasley RW, Thorne CH, eds. Grabb & Smith’s Plastic Surgery. Philadelphia: Lippincott Williams & Wilkins; 1997:295-304.
2. Buchman SR, Muraszko KM. Syndromic craniosynostosis. In: Lin KY, Ogle RC, Jane JA, eds. Craniofacial Surgery: Science and Surgical Technique. Philadelphia: WB Saunders; 2002:252-271.