- Email: [email protected]
Developmental anomalies of the skin
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37 (2013) 20–25
Available online at www.sciencedirect.com
www.elsevier.com/locate/semperi
Developmental anomalies of the skin Jane Sanders Bellet, MDn Departments of Dermatology and Pediatrics, Duke University Medical Center, Durham, NC
article info
a bs t r a c t This paper focuses on the diagnosis and management of developmental anomalies of the
Keywords:
skin that may be seen early in life. Common locations include the head, nose, preauricular
Developmental anomalies
area of the face, neck, and spine. Those that occur in or near the midline can be more
Cephalocele
serious because of possible intracranial connections. Radiologic imaging of the areas of
Aplasia cutis congenita
involvement is often important; computed tomography (CT) scans can delineate bony
Dermoid cyst
defects; whereas, magnetic resonance imaging (MRI) more clearly defines intracranial
Spinal dysraphism
connections. Occult spinal dysraphism can be suspected when certain cutaneous signs are present. & 2013 Elsevier Inc. All rights reserved.
Developmental anomalies of the skin A number of developmental anomalies involve the skin and may be seen early in life. Common locations include the head, nose, preauricular area of the face, neck, and spine. Some lesions can occur in more than one location. Those that occur in or near the midline, especially involving the head, nose, and spine, can be more serious because of possible central nervous system connections. Current thought is that the neural tube fuses in noncontinuous, discrete segments, predisposing these anomalies to occur with higher frequency at the intervening junctions.1 This discussion focuses on the diagnosis and management of these anomalies.
Head Cephaloceles A cephalocele is a protrusion of intracranial structures through a defect in the skull and occurs because of abnormal separation of neuroectoderm from surface ectoderm in early gestation.2 The sac contains neural tissues and is usually covered by skin. The lesions may be classified by the contents n
of the sac and the location of the cranial defect through which the protrusion occurs.3 A cranial meningocele contains only meninges and cerebrospinal fluid, while a cranial encephalocele (meningoencephalocele) not only contains meninges and cerebrospinal fluid, but also cerebral or cerebellar tissue. A cranial encephalocystocele contains portions of the ventricles, sometimes with choroid plexus.3 The most common presentation of an encephalocele is a soft, skin colored or bluish compressible mass that can transilluminate. The size varies from a few millimeters to more than 5 cm.3 The mass can enlarge with straining or crying, confirming a central nervous system (CNS) connection. Cephaloceles occur most commonly in the occipital area of the scalp, but they also occur in the frontoethmoidal area, and less frequently in the parietal, lateral, and skull base areas.3 Occipital cephaloceles are usually in the midline, but also can occur up to 3 cm lateral to the midline. Frontoethmoid lesions can involve the nasofrontal, nasoethmoid, and naso-orbital areas. Parietal lesions usually occur near the anterior or posterior fontanelle, while lateral ones are found along the coronal or lambdoid sutures.3 An external mass is rarely seen with a skull base cephalocele, unless it is so large that it protrudes through the nares.3 All suspected cephaloceles require radiologic evaluation, usually a combination of computed tomography (CT) and magnetic resonance imaging (MRI). CT is most useful to assess
Correspondence address. 40 Duke Medicine Circle, Box 3252, Durham, NC 27710. E-mail address: [email protected]
0146-0005/13/$ - see front matter & 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.semperi.2012.11.006
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defects of the skull, while MRI is more helpful to determine if an intracranial connection exists. The treatment is surgical.
Dermoid cysts and sinuses Though dermoid cysts are congenital lesions, they may not be noticed until early childhood, when they begin to grow.4 Abnormal embryologic development along embryonic fusion lines, either on the face or along the neural axis, determines their location.4 They may involve the scalp, face, nose, neck, and spine. The most common location on the scalp is the area overlying the anterior fontanelle at the junction of the sagittal and coronal sutures, and on the face is the area of the lateral eyebrow. They are smooth, firm, noncompressible, skincolored or bluish nodules that vary in size from less than 1–4 cm. They do not transilluminate or enlarge with crying or straining.4 Dermoid sinuses are usually midline tracts that connect the dermoid cyst to the skin surface. They may be found on the occipital scalp, nose, and spinal axis.4 Purulent material may drain if the cyst or sinus becomes infected, and there is a risk of meningitis if there is communication with the CNS. For this reason, all midline dermoid cysts and sinuses require radiologic imaging prior to surgical excision. MRI is most sensitive in determining whether there is a connection to the CNS, while CT is better able to delineate bony defects. Lesions involving the lateral eyebrow do not require any imaging because they do not connect to the CNS (Fig. 1). The treatment of dermoid cysts and sinuses is surgical excision.
Aplasia cutis congenita Aplasia cutis congenita (ACC) is the localized absence of skin that can occur anywhere on the body including the face, trunk, and extremities, but the most common area is the vertex of the scalp.2 There is no single cause, and Frieden has proposed a classification system of nine groups based on the affected body area and the presence or absence of associated abnormalities.4,5 ACC usually presents as an isolated finding with a round to oval, well-demarcated, scar-like, weeping or granulating, hairless defect that usually varies in size from 1 to 3 cm. The lesions are usually single, but may be multiple. Some lesions present with a thin membrane (membranous
Fig. 1 – Dermoid cyst, lateral eyebrow.
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or bullous ACC) and the most common location is on the scalp at or near the vertex. Hair does not grow within the membrane, however a ring of long, thick, often darker colored hairs (hair collar sign) can be found growing around the membrane (Fig. 2). Some believe that this defect is not a form of ACC, but rather a forme fruste of a neural tube defect with improper closure of ectoderm, and suggest that an MRI be performed to determine whether there is a defect in the skull and any connection to the CNS.6 Biopsy, drainage or excision of these lesions should not be undertaken without prior imaging. Any overlying crust or scab should not be manipulated, particularly over the area of the sagittal sinus, because fatal hemorrhage can occur (Fig. 3).3 The small superficial lesions tend to gradually heal in the weeks to months following birth often leaving a scar. The treatment of these lesions involves gentle cleansing and petrolatum or topical antibiotic ointment. Larger areas of involvement which are associated with defects of the skull and have a connection to the CNS require surgery to prevent complications such as meningitis, sagittal sinus thrombosis, and hemorrhage.7 Though ACC is usually an isolated finding or an autosomal dominant trait, it also may be seen in several syndromes. For example, if limb anomalies are present, Adams–Oliver syndrome, consisting of neurologic and cardiac abnormalities in association with transverse limb defects should be considered.8 Orbital cysts, skin tags, and cerebral malformations in conjunction with aplasia cutis congenita raise the possibility of Delleman syndrome (oculocerebrocutaneous syndrome).9 ACC can also be associated with fetus papyraceus (trunk and extremities), epidermolysis bullosa, maternal methimazole ingestion, prenatal herpesvirus infections, and trisomy 13.
Heterotopic brain tissue Heterotopic brain tissue refers to the presence of meningothelial and/or glial tissue found in the subcutaneous tissue or dermis. It is a rare lesion that occurs most often on the scalp, usually in the parietal or occipital areas and is often midline. The firm or cystic mass may be red, blue, or skincolored. Although it does not contain any hair, it may be surrounded by a ring of dark, coarse hairs (hair collar sign). This sign may also be seen with other scalp defects such as cephaloceles and membranous ACC. Because an intracranial
Fig. 2 – Aplasia cutis congenita with hair collar sign.
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Fig. 3 – Aplasia cutis congenita with hemorrhagic crust overlying the superior sagittal sinus. connection can exist, MRI should be performed prior to surgical excision.10
Nose Nasal encephalocele These midline lesions always have a connection to the CNS. When the dura retracts during embryogenesis, the connection to the CNS remains. They present at birth or in early infancy as soft, compressible, bluish masses involving the nasal bridge. They contain cerebrospinal fluid and transilluminate. They may also be pulsatile and can enlarge with crying or straining. MRI locates the lesion and delineates the connection to the CNS, and CT better determines any bony defects. Biopsy of these lesions is strongly contraindicated. The treatment is surgical excision.
Nasal glioma A nasal glioma is a midline lesion that contains rests of ectopic neural tissue. Only rarely does a stalk connect these lesions intracranially.11,12 They are firm, noncompressible, skin-colored or bluish nodules that do not transilluminate. They most commonly occur on the nasal bridge; however, they also can be seen along the inner canthus, on the nasal tip, or within the nose. Hypertelorism may be present secondary to widening of the nasal bone. MRI should be performed to locate the lesion and determine if there is an intracranial connection. The treatment is surgical excision.
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Fig. 4 – Nasal dermoid cyst with pit. When a dermoid cyst and/or sinus is suspected, CT is most useful to look for bony defects, whereas an MRI is more conclusive in determining the presence of intracranial connection. Any manipulation such as probing, biopsy, or excision should not be undertaken until the results of imaging are known. The treatment is surgical excision to prevent infection and damage to the nasal architecture.
Preauricular area Pits and accessory tragi (tags) Skin pits are small (1–2 mm) and usually occur on the anterior margin of the ascending helix or in the preauricular area. They can be superficial or extend into the pinna and are usually asymptomatic, unless they become infected.15 Surgical treatment is not usually required, unless they become chronically infected.2 Accessory tragi (skin tags) are skin-colored papular lesions that also occur in the preauricular area; they can be unilateral or bilateral (Fig. 5). Some are composed of only dermis, but many contain a cartilaginous core. Surgical excision is usually for appearance, unless they become infected recurrently. In most children with an isolated pit or tag, there are no other associated abnormalities. However, hearing loss may occur in some infants with isolated preauricular pits and tags, and testing of hearing has been recommended for these
Nasal dermoid cysts and sinuses These midline cysts appear as mobile, noncompressible, nontender, subcutaneous nodules that can occur anywhere from the glabella to the tip of the nose. A pit or sinus is often present (Fig. 4). A few hairs may be seen at the opening and sometimes a keratinaceous discharge can be expressed.13 Sinus tracts may end superficially or in deeper nasal structures and can become infected. They also can extend intracranially in 25% of the cases, and these patients are at risk for the development of bacterial meningitis and brain abscess.14
Fig. 5 – Accessory tragi.
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patients.16,17 There is controversy about whether there is an increased incidence of urinary tract abnormalities in infants with isolated preauricular pits and tags and whether renal ultrasound should be performed.17,18 Wang et al. recommend that a renal ultrasound should be performed in patients with a preauricular pit or tag who have one or more of the following: other malformations or dysmorphic features; a family history of deafness, auricular and/or renal malformations; or a maternal history of gestational diabetes.19 If multiple accessory tragi are present, often unilaterally, along with either a malformed ear, nose, lip, or mandible; or hearing loss or limbal dermoids, the diagnosis of Goldenhar (oculoauriculovertebral) syndrome should be considered.
Periauricular cysts and sinuses—First branchial cleft defects (type I) See discussion of branchial system anomalies in the Neck section.
Neck Thyroglossal duct cysts These skin-colored, soft, round to oval, 1–2 cm cystic nodules appear in the midline or just lateral to the midline, anywhere from the hyoid bone to the suprasternal notch. They often move upward with swallowing or protrusion of the tongue due to attachment to the hyoid bone,7 except for those located in the lower part of the neck. They may be first noticed at birth, in infancy, or in childhood and are the most common anomaly of the anterior neck. Ultrasound can identify the presence of a normal thyroid gland.20 If a normal thyroid gland cannot be identified, radioisotope scanning of the neck should be considered to determine whether the mass contains ectopic thyroid tissue, which may be the only source of thyroid hormone.21 Thyroid function test results can be normal if the ectopic thyroid is producing enough hormone. Surgical excision is recommended to prevent infection and the uncommon complication of thyroid carcinoma. Thyroid hormone replacement is necessary after excision, if the mass contains the only functioning thyroid tissue.
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Branchial system anomalies22 Anomalies of the branchial system consist of sinuses, fistulas, and cysts. The most common defects arise from the second branchial system. Those of the first branchial system are less common, while third and fourth branchial defects are even rarer. First branchial defects can be seen on the face and neck. There are two anatomical types of first branchial cleft defects. In type I, the cyst or sinus opening occurs medial, inferior, or posterior to the ear cartilage and pinna, and any sinus tract is parallel to the external auditory meatus. In type II, the cyst or sinus opening is in the anterior portion of the neck always superior to the hyoid bone, and the sinus or fistula continues over the angle of the mandible terminating near the external ear canal. Because these defects can be close to the facial nerve, they should be excised before they become infected. Second branchial defects appear in the neck. Sinuses and fistulas have an opening to the skin that can occur between the middle and lower third of the anterior sternocleidomastoid muscle (anterior triangle of the neck) below the level of the hyoid bone, and an internal opening can occur in the tonsillar fossae. Cysts may occur anywhere along the sinus tract, but their location is commonly in the anterior triangle of the neck, below the hyoid bone. An external opening of a third branchial anomaly occurs in the same area as those associated with a second branchial anomaly; however, the internal opening occurs within the piriform sinus. The sinus tract terminates in the anterolateral area of the neck. Though cysts can occur anywhere along the tract, they commonly occur in the lower aspect of the anterior cervical triangle. The sinus tract of a fourth branchial anomaly terminates in the anterior inferior area of the neck. The external opening of a sinus tract is often seen in the newborn period with the secretion of mucus-like material. In contrast, a branchial cleft cyst may not be diagnosed for years until the cyst enlarges or becomes infected. MRI is useful in determining the presence of unsuspected sinus tracts. Contrast material may be injected into an external opening to outline the tracts. The treatment of these cysts and sinus tracts is surgical excision.
Dermoid cysts Midline cervical clefts These lesions are round to oval, firm, 1–2 cm nodules which occur in the midline, anywhere from the mandible to the lower part of the neck. They are often mistaken for thyroglossal duct cysts because some of them move with swallowing. An ultrasound is normally performed to help differentiate this lesion from a thyroglossal duct cyst. Because dermoid cysts of the neck do not connect to the CNS, no further imaging is necessary. This is in contrast to midline scalp and nasal dermoid cysts, where intracranial connections can occur and further investigation is necessary prior to any intervention. The treatment of dermoid cysts of the neck is surgical excision.
Though the cause of these rare lesions is unknown, they may be due to abnormal first or second branchial arch development.7 They present in the midline of the anterior aspect of the neck anywhere between the mandible and sternum with a skin-colored appendage superiorly, a sinus inferiorly, and atrophic skin in between.7,23 They can also be associated with other midline lesions such as clefting of the lower lip, tongue, and mandible as well as midline neck hypoplasia.24 The treatment is surgical excision to prevent infection and neck contracture secondary to tethering of the mandible due to a midline fibrous band.23
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Congenital cartilaginous rests of the neck (wattles) This rare anomaly may represent a branchial arch remnant or ectopic auricular tissue.25 These soft, mobile, skin-colored nodular appendages may contain cartilage and can occur anywhere in the neck, but are most commonly seen over the lower half of the sternocleidomastoid muscle. They are present at birth and can be either single or multiple, unilateral or bilateral. Surgical excision of these lesions is usually for appearance. They do not require imaging prior to removal, since no deep connection exists.
Bronchogenic cysts and sinuses These cysts may develop from ectopic components of the tracheobronchial tree or from abnormal branchial arch development.15 They usually present early in life as a nodule or draining sinus over the suprasternal notch. They neither connect to deeper structures nor are they usually associated with other malformations.4 Surgical excision should be performed to prevent recurrent infection.
Spine Incomplete fusion of midline mesenchymal, bony, and neural structures produces a number of spine anomalies termed spinal dysraphism.7 The most common open or non-skincoveredlesions are myelocele and myelomeningocele, while the most common skin-covered ones include dermal sinus, spinal lipoma, meningocele, diastematomyelia, neurenteric cyst, and tight filum terminale or tethered cord.26 The nonskin covered anomalies appear as protruding spinal masses and are obvious at birth. The skin-covered anomalies may present with cutaneous findings that suggest the presence of an underlying spine abnormality (occult spinal dysraphism). Failure of neural tube separation from the overlying ectoderm and the abnormal insertion of mesoderm between these layers can produce these findings.27 The most common location is the lumbosacral area, but the cervical and thoracic areas can also be involved. There should be a high index of suspicion for spinal dysraphism with the following midline cutaneous findings: lipomas; localized lumbosacral hypertrichosis or aplasia cutis; dermoid cyst or sinus; deep and large dimples (40.5 cm) located above the gluteal crease (42.5 cm from the anus)7,15,28; infantile hemangiomas (44 cm); and acrochordons (skin-colored papules or nodules), tails (a finger-like appendage), and pseudotails (stump-like structure).7,15,28 Cutaneous findings with a lower index of suspicion for spinal dysraphism include hyper-pigmentation or hypo-pigmentation, congenital melanocytic nevi, telangiectasia, capillary malformation (port-wine stain), and small sacral dimples with a visible base o2.5 cm from the anus.7,28 More than one finding can occur and this increases the likelihood of an underlying defect (Fig. 6).28 Capillary malformations (nevus flammeus) of the posterior cervical area are not associated with spinal dysraphism.15,28 At birth or early in life, other findings may be seen that suggest the possibility of spinal dysraphism. These include unequal size of the buttocks, an asymmetric gluteal cleft, a
Figure 6 – Multiple congenital lumbosacral anomalies (segmental hemangioma, asymmetric gluteal cleft, atypical dimple, and pseudotail) overlying an occult lipomyelomeningocele. (Courtesy of Richard Antaya, MD.) palpable vertebral defect, and anorectal malformations such as imperforate anus and cloacal exstrophy.29 A history of recurrent urinary tract infections; urinary and/or fecal incontinence; back pain; weakness, atrophy, or decreased sensation in lower extremities; an abnormal gait; or scoliosis may also indicate the presence of spinal dysraphism. These findings are sometimes difficult to ascertain in a very young child. Before 6 months of age, ultrasound of the spine can be performed as a screening procedure before ossification of the vertebrae occurs,30 however MRI is more sensitive and should be considered when there is a high index of suspicion. If spinal dysraphism is found on ultrasound, an MRI should be performed. In older infants and children, MRI is the imaging study of choice. The treatment of spinal dysraphism is surgical.
r e fe ren c e s
1. Nakatsu T, Uwabe C, Shiota K. Neural tube closure in humans initiates at multiple sites: evidence from human embryos and implications for the pathogenesis of neural tube defects. Anat Embryol (Berl). 2000;201(6):455–466. 2. Paller A, Mancini A. In: Cutaneous Disorders of the Newborn. Hurwitz: Clinical Pediatric Dermatology. Philadelphia: Elsevier Saunders; 2006 17–47. 3. Kollias S, Ball W. Congenital malformations of the brain. In: Ball WS, Pediatric Neuroradiology. Philadelphia: LippincottRaven; 1997. p. 91–174. 4. Kos L, Drolet B. Developmental abnormalities. In: Eichenfield LF, Frieden IJ, Esterly NB, Neonatal Dermatology, 2nd ed., Philadelphia: Elsevier Saunders; 2008. p. 113–130. 5. Frieden IJ. Aplasia cutis congenita: a clinical review and proposal for classification. J Am Acad Dermatol. 1986;14(4):646–660. 6. Drolet B, Prendiville J, Golden J, Enjolras O, Esterly NB. ’Membranous aplasia cutis’ with hair collars. Congenital absence of skin or neuroectodermal defect? Arch Dermatol. 1995;131(12):1427–1431. 7. Hamm H. Developmental Abnormalities. In: Irvine A, Hoeger P, Yan AC, Harper’s Textbook of Pediatric Dermatology, 3rd ed., Chichester, UK: Wiley-Blackwell; 2011. p. 10.1–10.22.
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8. Mempel M, Abeck D, Lange I, Strom K, Caliebe A, Beham A, et al. The wide spectrum of clinical expression in Adams–Oliver syndrome: a report of two cases. Br J Dermatol. 1999;140(6):1157–1160. 9. McCandless SE, Robin NH. Severe oculocerebrocutaneous (Delleman) syndrome: overlap with Goldenhar anomaly. Am J Med Genet. 1998;78(3):282–285. 10. Rogers GF, Mulliken JB, Kozakewich HP. Heterotopic neural nodules of the scalp. Plast Reconstr Surg. 2005;115(2):376–382. 11. Smith Jr. KR, Schwartz HG, Luse SA, Ogura JH. Nasal gliomas: a report of five cases with electron microscopy of one. J Neurosurg. 1963;20:968–982. 12. Karma P, Rasanen O, Karja J. Nasal gliomas. A review and report of two cases. Laryngoscope. 1977;87(7):1169–1179. 13. Farvolden D, Sweeney SM, Wiss K. Lumps and bumps in neonates and infants. Dermatol Ther. 2005;18(2):104–116. 14. Paller AS, Pensler JM, Tomita T. Nasal midline masses in infants and children. Dermoids, encephaloceles, and gliomas. Arch Dermatol. 1991;127(3):362–366. 15. Howard R. Cutaneous markers of congenital malformations: diagnosis and management. Adv Dermatol. 1999;15:1–30. 16. Roth DA, Hildesheimer M, Bardenstein S, et al. Preauricular skin tags and ear pits are associated with permanent hearing impairment in newborns. Pediatrics. 2008;122(4):e884–e890. 17. Kugelman A, Tubi A, Bader D, Chemo M, Dabbah H. Preauricular tags and pits in the newborn: the role of renal ultrasonography. J Pediatr. 2002;141(3):388–391. 18. Kohelet D, Arbel E. A prospective search for urinary tract abnormalities in infants with isolated preauricular tags. Pediatrics. 2000;105(5):E61.
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19. Wang RY, Earl DL, Ruder RO, Graham Jr. JM. Syndromic ear anomalies and renal ultrasounds. Pediatrics. 2001;108(2):E32. 20. Ahuja AT, Wong KT, King AD, Yuen EH. Imaging for thyroglossal duct cyst: the bare essentials. Clin Radiol. 2005; 60(2):141–148. 21. Joseph J, Lim K, Ramsden J. Investigation prior to thyroglossal duct cyst excision. Ann R Coll Surg Engl 2012;94(3):181–184. 22. Cunningham MJ. Congenital malformations of the head and neck. In: Cotton R, Myers C, Practical Pediatric Otolaryngology. Philadelphia: Lippincott-Raven; 1999. p. 663–680. 23. Gardner RO, Moss AL. The congenital cervical midline cleft. Case report and review of literature. Br J Plast Surg. 2005;58(3):399–403. 24. Gargan TJ, McKinnon M, Mulliken JB. Midline cervical cleft. Plast Reconstr Surg 1985 Aug;76(2):225–229. 25. Clarke JA. Are wattles of auricular or branchial origin? Br J Plast Surg 1976;29(3):238–244. 26. Egelhoff JCPE, Coly BD. The spine. In: Ball WS, Pediatric Neuroradiology. Philadelphia: Lippincott-Raven; 1997. p. 717–778. 27. Khwaja O. Disturbances of the neural tube and spinal closure. In: Rudolph CD, Rudolph’s pediatrics, 22nd ed., New York: McGraw Hill Medical; 2011. p. 2154–2155. 28. Drolet B. Birthmarks to worry about. Cutaneous markers of dysraphism. Dermatol Clin. 1998;16(3):447–453. 29. Karrer FM, Flannery AM, Nelson Jr. MD, McLone DG, Raffensperger JG. Anorectal malformations: evaluation of associated spinal dysraphic syndromes. J Pediatr Surg. 1988;23(1 Pt 2):45–48. 30. Rohrschneider WK, Forsting M, Darge K, Troger J. Diagnostic value of spinal US: comparative study with MR imaging in pediatric patients. Radiology 1996;200(2):383–388.
M I N A R S I N
PE
R I N AT O L O G Y
37 (2013) 20–25
Available online at www.sciencedirect.com
www.elsevier.com/locate/semperi
Developmental anomalies of the skin Jane Sanders Bellet, MDn Departments of Dermatology and Pediatrics, Duke University Medical Center, Durham, NC
article info
a bs t r a c t This paper focuses on the diagnosis and management of developmental anomalies of the
Keywords:
skin that may be seen early in life. Common locations include the head, nose, preauricular
Developmental anomalies
area of the face, neck, and spine. Those that occur in or near the midline can be more
Cephalocele
serious because of possible intracranial connections. Radiologic imaging of the areas of
Aplasia cutis congenita
involvement is often important; computed tomography (CT) scans can delineate bony
Dermoid cyst
defects; whereas, magnetic resonance imaging (MRI) more clearly defines intracranial
Spinal dysraphism
connections. Occult spinal dysraphism can be suspected when certain cutaneous signs are present. & 2013 Elsevier Inc. All rights reserved.
Developmental anomalies of the skin A number of developmental anomalies involve the skin and may be seen early in life. Common locations include the head, nose, preauricular area of the face, neck, and spine. Some lesions can occur in more than one location. Those that occur in or near the midline, especially involving the head, nose, and spine, can be more serious because of possible central nervous system connections. Current thought is that the neural tube fuses in noncontinuous, discrete segments, predisposing these anomalies to occur with higher frequency at the intervening junctions.1 This discussion focuses on the diagnosis and management of these anomalies.
Head Cephaloceles A cephalocele is a protrusion of intracranial structures through a defect in the skull and occurs because of abnormal separation of neuroectoderm from surface ectoderm in early gestation.2 The sac contains neural tissues and is usually covered by skin. The lesions may be classified by the contents n
of the sac and the location of the cranial defect through which the protrusion occurs.3 A cranial meningocele contains only meninges and cerebrospinal fluid, while a cranial encephalocele (meningoencephalocele) not only contains meninges and cerebrospinal fluid, but also cerebral or cerebellar tissue. A cranial encephalocystocele contains portions of the ventricles, sometimes with choroid plexus.3 The most common presentation of an encephalocele is a soft, skin colored or bluish compressible mass that can transilluminate. The size varies from a few millimeters to more than 5 cm.3 The mass can enlarge with straining or crying, confirming a central nervous system (CNS) connection. Cephaloceles occur most commonly in the occipital area of the scalp, but they also occur in the frontoethmoidal area, and less frequently in the parietal, lateral, and skull base areas.3 Occipital cephaloceles are usually in the midline, but also can occur up to 3 cm lateral to the midline. Frontoethmoid lesions can involve the nasofrontal, nasoethmoid, and naso-orbital areas. Parietal lesions usually occur near the anterior or posterior fontanelle, while lateral ones are found along the coronal or lambdoid sutures.3 An external mass is rarely seen with a skull base cephalocele, unless it is so large that it protrudes through the nares.3 All suspected cephaloceles require radiologic evaluation, usually a combination of computed tomography (CT) and magnetic resonance imaging (MRI). CT is most useful to assess
Correspondence address. 40 Duke Medicine Circle, Box 3252, Durham, NC 27710. E-mail address: [email protected]
0146-0005/13/$ - see front matter & 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1053/j.semperi.2012.11.006
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defects of the skull, while MRI is more helpful to determine if an intracranial connection exists. The treatment is surgical.
Dermoid cysts and sinuses Though dermoid cysts are congenital lesions, they may not be noticed until early childhood, when they begin to grow.4 Abnormal embryologic development along embryonic fusion lines, either on the face or along the neural axis, determines their location.4 They may involve the scalp, face, nose, neck, and spine. The most common location on the scalp is the area overlying the anterior fontanelle at the junction of the sagittal and coronal sutures, and on the face is the area of the lateral eyebrow. They are smooth, firm, noncompressible, skincolored or bluish nodules that vary in size from less than 1–4 cm. They do not transilluminate or enlarge with crying or straining.4 Dermoid sinuses are usually midline tracts that connect the dermoid cyst to the skin surface. They may be found on the occipital scalp, nose, and spinal axis.4 Purulent material may drain if the cyst or sinus becomes infected, and there is a risk of meningitis if there is communication with the CNS. For this reason, all midline dermoid cysts and sinuses require radiologic imaging prior to surgical excision. MRI is most sensitive in determining whether there is a connection to the CNS, while CT is better able to delineate bony defects. Lesions involving the lateral eyebrow do not require any imaging because they do not connect to the CNS (Fig. 1). The treatment of dermoid cysts and sinuses is surgical excision.
Aplasia cutis congenita Aplasia cutis congenita (ACC) is the localized absence of skin that can occur anywhere on the body including the face, trunk, and extremities, but the most common area is the vertex of the scalp.2 There is no single cause, and Frieden has proposed a classification system of nine groups based on the affected body area and the presence or absence of associated abnormalities.4,5 ACC usually presents as an isolated finding with a round to oval, well-demarcated, scar-like, weeping or granulating, hairless defect that usually varies in size from 1 to 3 cm. The lesions are usually single, but may be multiple. Some lesions present with a thin membrane (membranous
Fig. 1 – Dermoid cyst, lateral eyebrow.
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or bullous ACC) and the most common location is on the scalp at or near the vertex. Hair does not grow within the membrane, however a ring of long, thick, often darker colored hairs (hair collar sign) can be found growing around the membrane (Fig. 2). Some believe that this defect is not a form of ACC, but rather a forme fruste of a neural tube defect with improper closure of ectoderm, and suggest that an MRI be performed to determine whether there is a defect in the skull and any connection to the CNS.6 Biopsy, drainage or excision of these lesions should not be undertaken without prior imaging. Any overlying crust or scab should not be manipulated, particularly over the area of the sagittal sinus, because fatal hemorrhage can occur (Fig. 3).3 The small superficial lesions tend to gradually heal in the weeks to months following birth often leaving a scar. The treatment of these lesions involves gentle cleansing and petrolatum or topical antibiotic ointment. Larger areas of involvement which are associated with defects of the skull and have a connection to the CNS require surgery to prevent complications such as meningitis, sagittal sinus thrombosis, and hemorrhage.7 Though ACC is usually an isolated finding or an autosomal dominant trait, it also may be seen in several syndromes. For example, if limb anomalies are present, Adams–Oliver syndrome, consisting of neurologic and cardiac abnormalities in association with transverse limb defects should be considered.8 Orbital cysts, skin tags, and cerebral malformations in conjunction with aplasia cutis congenita raise the possibility of Delleman syndrome (oculocerebrocutaneous syndrome).9 ACC can also be associated with fetus papyraceus (trunk and extremities), epidermolysis bullosa, maternal methimazole ingestion, prenatal herpesvirus infections, and trisomy 13.
Heterotopic brain tissue Heterotopic brain tissue refers to the presence of meningothelial and/or glial tissue found in the subcutaneous tissue or dermis. It is a rare lesion that occurs most often on the scalp, usually in the parietal or occipital areas and is often midline. The firm or cystic mass may be red, blue, or skincolored. Although it does not contain any hair, it may be surrounded by a ring of dark, coarse hairs (hair collar sign). This sign may also be seen with other scalp defects such as cephaloceles and membranous ACC. Because an intracranial
Fig. 2 – Aplasia cutis congenita with hair collar sign.
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Fig. 3 – Aplasia cutis congenita with hemorrhagic crust overlying the superior sagittal sinus. connection can exist, MRI should be performed prior to surgical excision.10
Nose Nasal encephalocele These midline lesions always have a connection to the CNS. When the dura retracts during embryogenesis, the connection to the CNS remains. They present at birth or in early infancy as soft, compressible, bluish masses involving the nasal bridge. They contain cerebrospinal fluid and transilluminate. They may also be pulsatile and can enlarge with crying or straining. MRI locates the lesion and delineates the connection to the CNS, and CT better determines any bony defects. Biopsy of these lesions is strongly contraindicated. The treatment is surgical excision.
Nasal glioma A nasal glioma is a midline lesion that contains rests of ectopic neural tissue. Only rarely does a stalk connect these lesions intracranially.11,12 They are firm, noncompressible, skin-colored or bluish nodules that do not transilluminate. They most commonly occur on the nasal bridge; however, they also can be seen along the inner canthus, on the nasal tip, or within the nose. Hypertelorism may be present secondary to widening of the nasal bone. MRI should be performed to locate the lesion and determine if there is an intracranial connection. The treatment is surgical excision.
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Fig. 4 – Nasal dermoid cyst with pit. When a dermoid cyst and/or sinus is suspected, CT is most useful to look for bony defects, whereas an MRI is more conclusive in determining the presence of intracranial connection. Any manipulation such as probing, biopsy, or excision should not be undertaken until the results of imaging are known. The treatment is surgical excision to prevent infection and damage to the nasal architecture.
Preauricular area Pits and accessory tragi (tags) Skin pits are small (1–2 mm) and usually occur on the anterior margin of the ascending helix or in the preauricular area. They can be superficial or extend into the pinna and are usually asymptomatic, unless they become infected.15 Surgical treatment is not usually required, unless they become chronically infected.2 Accessory tragi (skin tags) are skin-colored papular lesions that also occur in the preauricular area; they can be unilateral or bilateral (Fig. 5). Some are composed of only dermis, but many contain a cartilaginous core. Surgical excision is usually for appearance, unless they become infected recurrently. In most children with an isolated pit or tag, there are no other associated abnormalities. However, hearing loss may occur in some infants with isolated preauricular pits and tags, and testing of hearing has been recommended for these
Nasal dermoid cysts and sinuses These midline cysts appear as mobile, noncompressible, nontender, subcutaneous nodules that can occur anywhere from the glabella to the tip of the nose. A pit or sinus is often present (Fig. 4). A few hairs may be seen at the opening and sometimes a keratinaceous discharge can be expressed.13 Sinus tracts may end superficially or in deeper nasal structures and can become infected. They also can extend intracranially in 25% of the cases, and these patients are at risk for the development of bacterial meningitis and brain abscess.14
Fig. 5 – Accessory tragi.
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patients.16,17 There is controversy about whether there is an increased incidence of urinary tract abnormalities in infants with isolated preauricular pits and tags and whether renal ultrasound should be performed.17,18 Wang et al. recommend that a renal ultrasound should be performed in patients with a preauricular pit or tag who have one or more of the following: other malformations or dysmorphic features; a family history of deafness, auricular and/or renal malformations; or a maternal history of gestational diabetes.19 If multiple accessory tragi are present, often unilaterally, along with either a malformed ear, nose, lip, or mandible; or hearing loss or limbal dermoids, the diagnosis of Goldenhar (oculoauriculovertebral) syndrome should be considered.
Periauricular cysts and sinuses—First branchial cleft defects (type I) See discussion of branchial system anomalies in the Neck section.
Neck Thyroglossal duct cysts These skin-colored, soft, round to oval, 1–2 cm cystic nodules appear in the midline or just lateral to the midline, anywhere from the hyoid bone to the suprasternal notch. They often move upward with swallowing or protrusion of the tongue due to attachment to the hyoid bone,7 except for those located in the lower part of the neck. They may be first noticed at birth, in infancy, or in childhood and are the most common anomaly of the anterior neck. Ultrasound can identify the presence of a normal thyroid gland.20 If a normal thyroid gland cannot be identified, radioisotope scanning of the neck should be considered to determine whether the mass contains ectopic thyroid tissue, which may be the only source of thyroid hormone.21 Thyroid function test results can be normal if the ectopic thyroid is producing enough hormone. Surgical excision is recommended to prevent infection and the uncommon complication of thyroid carcinoma. Thyroid hormone replacement is necessary after excision, if the mass contains the only functioning thyroid tissue.
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Branchial system anomalies22 Anomalies of the branchial system consist of sinuses, fistulas, and cysts. The most common defects arise from the second branchial system. Those of the first branchial system are less common, while third and fourth branchial defects are even rarer. First branchial defects can be seen on the face and neck. There are two anatomical types of first branchial cleft defects. In type I, the cyst or sinus opening occurs medial, inferior, or posterior to the ear cartilage and pinna, and any sinus tract is parallel to the external auditory meatus. In type II, the cyst or sinus opening is in the anterior portion of the neck always superior to the hyoid bone, and the sinus or fistula continues over the angle of the mandible terminating near the external ear canal. Because these defects can be close to the facial nerve, they should be excised before they become infected. Second branchial defects appear in the neck. Sinuses and fistulas have an opening to the skin that can occur between the middle and lower third of the anterior sternocleidomastoid muscle (anterior triangle of the neck) below the level of the hyoid bone, and an internal opening can occur in the tonsillar fossae. Cysts may occur anywhere along the sinus tract, but their location is commonly in the anterior triangle of the neck, below the hyoid bone. An external opening of a third branchial anomaly occurs in the same area as those associated with a second branchial anomaly; however, the internal opening occurs within the piriform sinus. The sinus tract terminates in the anterolateral area of the neck. Though cysts can occur anywhere along the tract, they commonly occur in the lower aspect of the anterior cervical triangle. The sinus tract of a fourth branchial anomaly terminates in the anterior inferior area of the neck. The external opening of a sinus tract is often seen in the newborn period with the secretion of mucus-like material. In contrast, a branchial cleft cyst may not be diagnosed for years until the cyst enlarges or becomes infected. MRI is useful in determining the presence of unsuspected sinus tracts. Contrast material may be injected into an external opening to outline the tracts. The treatment of these cysts and sinus tracts is surgical excision.
Dermoid cysts Midline cervical clefts These lesions are round to oval, firm, 1–2 cm nodules which occur in the midline, anywhere from the mandible to the lower part of the neck. They are often mistaken for thyroglossal duct cysts because some of them move with swallowing. An ultrasound is normally performed to help differentiate this lesion from a thyroglossal duct cyst. Because dermoid cysts of the neck do not connect to the CNS, no further imaging is necessary. This is in contrast to midline scalp and nasal dermoid cysts, where intracranial connections can occur and further investigation is necessary prior to any intervention. The treatment of dermoid cysts of the neck is surgical excision.
Though the cause of these rare lesions is unknown, they may be due to abnormal first or second branchial arch development.7 They present in the midline of the anterior aspect of the neck anywhere between the mandible and sternum with a skin-colored appendage superiorly, a sinus inferiorly, and atrophic skin in between.7,23 They can also be associated with other midline lesions such as clefting of the lower lip, tongue, and mandible as well as midline neck hypoplasia.24 The treatment is surgical excision to prevent infection and neck contracture secondary to tethering of the mandible due to a midline fibrous band.23
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Congenital cartilaginous rests of the neck (wattles) This rare anomaly may represent a branchial arch remnant or ectopic auricular tissue.25 These soft, mobile, skin-colored nodular appendages may contain cartilage and can occur anywhere in the neck, but are most commonly seen over the lower half of the sternocleidomastoid muscle. They are present at birth and can be either single or multiple, unilateral or bilateral. Surgical excision of these lesions is usually for appearance. They do not require imaging prior to removal, since no deep connection exists.
Bronchogenic cysts and sinuses These cysts may develop from ectopic components of the tracheobronchial tree or from abnormal branchial arch development.15 They usually present early in life as a nodule or draining sinus over the suprasternal notch. They neither connect to deeper structures nor are they usually associated with other malformations.4 Surgical excision should be performed to prevent recurrent infection.
Spine Incomplete fusion of midline mesenchymal, bony, and neural structures produces a number of spine anomalies termed spinal dysraphism.7 The most common open or non-skincoveredlesions are myelocele and myelomeningocele, while the most common skin-covered ones include dermal sinus, spinal lipoma, meningocele, diastematomyelia, neurenteric cyst, and tight filum terminale or tethered cord.26 The nonskin covered anomalies appear as protruding spinal masses and are obvious at birth. The skin-covered anomalies may present with cutaneous findings that suggest the presence of an underlying spine abnormality (occult spinal dysraphism). Failure of neural tube separation from the overlying ectoderm and the abnormal insertion of mesoderm between these layers can produce these findings.27 The most common location is the lumbosacral area, but the cervical and thoracic areas can also be involved. There should be a high index of suspicion for spinal dysraphism with the following midline cutaneous findings: lipomas; localized lumbosacral hypertrichosis or aplasia cutis; dermoid cyst or sinus; deep and large dimples (40.5 cm) located above the gluteal crease (42.5 cm from the anus)7,15,28; infantile hemangiomas (44 cm); and acrochordons (skin-colored papules or nodules), tails (a finger-like appendage), and pseudotails (stump-like structure).7,15,28 Cutaneous findings with a lower index of suspicion for spinal dysraphism include hyper-pigmentation or hypo-pigmentation, congenital melanocytic nevi, telangiectasia, capillary malformation (port-wine stain), and small sacral dimples with a visible base o2.5 cm from the anus.7,28 More than one finding can occur and this increases the likelihood of an underlying defect (Fig. 6).28 Capillary malformations (nevus flammeus) of the posterior cervical area are not associated with spinal dysraphism.15,28 At birth or early in life, other findings may be seen that suggest the possibility of spinal dysraphism. These include unequal size of the buttocks, an asymmetric gluteal cleft, a
Figure 6 – Multiple congenital lumbosacral anomalies (segmental hemangioma, asymmetric gluteal cleft, atypical dimple, and pseudotail) overlying an occult lipomyelomeningocele. (Courtesy of Richard Antaya, MD.) palpable vertebral defect, and anorectal malformations such as imperforate anus and cloacal exstrophy.29 A history of recurrent urinary tract infections; urinary and/or fecal incontinence; back pain; weakness, atrophy, or decreased sensation in lower extremities; an abnormal gait; or scoliosis may also indicate the presence of spinal dysraphism. These findings are sometimes difficult to ascertain in a very young child. Before 6 months of age, ultrasound of the spine can be performed as a screening procedure before ossification of the vertebrae occurs,30 however MRI is more sensitive and should be considered when there is a high index of suspicion. If spinal dysraphism is found on ultrasound, an MRI should be performed. In older infants and children, MRI is the imaging study of choice. The treatment of spinal dysraphism is surgical.
r e fe ren c e s
1. Nakatsu T, Uwabe C, Shiota K. Neural tube closure in humans initiates at multiple sites: evidence from human embryos and implications for the pathogenesis of neural tube defects. Anat Embryol (Berl). 2000;201(6):455–466. 2. Paller A, Mancini A. In: Cutaneous Disorders of the Newborn. Hurwitz: Clinical Pediatric Dermatology. Philadelphia: Elsevier Saunders; 2006 17–47. 3. Kollias S, Ball W. Congenital malformations of the brain. In: Ball WS, Pediatric Neuroradiology. Philadelphia: LippincottRaven; 1997. p. 91–174. 4. Kos L, Drolet B. Developmental abnormalities. In: Eichenfield LF, Frieden IJ, Esterly NB, Neonatal Dermatology, 2nd ed., Philadelphia: Elsevier Saunders; 2008. p. 113–130. 5. Frieden IJ. Aplasia cutis congenita: a clinical review and proposal for classification. J Am Acad Dermatol. 1986;14(4):646–660. 6. Drolet B, Prendiville J, Golden J, Enjolras O, Esterly NB. ’Membranous aplasia cutis’ with hair collars. Congenital absence of skin or neuroectodermal defect? Arch Dermatol. 1995;131(12):1427–1431. 7. Hamm H. Developmental Abnormalities. In: Irvine A, Hoeger P, Yan AC, Harper’s Textbook of Pediatric Dermatology, 3rd ed., Chichester, UK: Wiley-Blackwell; 2011. p. 10.1–10.22.
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8. Mempel M, Abeck D, Lange I, Strom K, Caliebe A, Beham A, et al. The wide spectrum of clinical expression in Adams–Oliver syndrome: a report of two cases. Br J Dermatol. 1999;140(6):1157–1160. 9. McCandless SE, Robin NH. Severe oculocerebrocutaneous (Delleman) syndrome: overlap with Goldenhar anomaly. Am J Med Genet. 1998;78(3):282–285. 10. Rogers GF, Mulliken JB, Kozakewich HP. Heterotopic neural nodules of the scalp. Plast Reconstr Surg. 2005;115(2):376–382. 11. Smith Jr. KR, Schwartz HG, Luse SA, Ogura JH. Nasal gliomas: a report of five cases with electron microscopy of one. J Neurosurg. 1963;20:968–982. 12. Karma P, Rasanen O, Karja J. Nasal gliomas. A review and report of two cases. Laryngoscope. 1977;87(7):1169–1179. 13. Farvolden D, Sweeney SM, Wiss K. Lumps and bumps in neonates and infants. Dermatol Ther. 2005;18(2):104–116. 14. Paller AS, Pensler JM, Tomita T. Nasal midline masses in infants and children. Dermoids, encephaloceles, and gliomas. Arch Dermatol. 1991;127(3):362–366. 15. Howard R. Cutaneous markers of congenital malformations: diagnosis and management. Adv Dermatol. 1999;15:1–30. 16. Roth DA, Hildesheimer M, Bardenstein S, et al. Preauricular skin tags and ear pits are associated with permanent hearing impairment in newborns. Pediatrics. 2008;122(4):e884–e890. 17. Kugelman A, Tubi A, Bader D, Chemo M, Dabbah H. Preauricular tags and pits in the newborn: the role of renal ultrasonography. J Pediatr. 2002;141(3):388–391. 18. Kohelet D, Arbel E. A prospective search for urinary tract abnormalities in infants with isolated preauricular tags. Pediatrics. 2000;105(5):E61.
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19. Wang RY, Earl DL, Ruder RO, Graham Jr. JM. Syndromic ear anomalies and renal ultrasounds. Pediatrics. 2001;108(2):E32. 20. Ahuja AT, Wong KT, King AD, Yuen EH. Imaging for thyroglossal duct cyst: the bare essentials. Clin Radiol. 2005; 60(2):141–148. 21. Joseph J, Lim K, Ramsden J. Investigation prior to thyroglossal duct cyst excision. Ann R Coll Surg Engl 2012;94(3):181–184. 22. Cunningham MJ. Congenital malformations of the head and neck. In: Cotton R, Myers C, Practical Pediatric Otolaryngology. Philadelphia: Lippincott-Raven; 1999. p. 663–680. 23. Gardner RO, Moss AL. The congenital cervical midline cleft. Case report and review of literature. Br J Plast Surg. 2005;58(3):399–403. 24. Gargan TJ, McKinnon M, Mulliken JB. Midline cervical cleft. Plast Reconstr Surg 1985 Aug;76(2):225–229. 25. Clarke JA. Are wattles of auricular or branchial origin? Br J Plast Surg 1976;29(3):238–244. 26. Egelhoff JCPE, Coly BD. The spine. In: Ball WS, Pediatric Neuroradiology. Philadelphia: Lippincott-Raven; 1997. p. 717–778. 27. Khwaja O. Disturbances of the neural tube and spinal closure. In: Rudolph CD, Rudolph’s pediatrics, 22nd ed., New York: McGraw Hill Medical; 2011. p. 2154–2155. 28. Drolet B. Birthmarks to worry about. Cutaneous markers of dysraphism. Dermatol Clin. 1998;16(3):447–453. 29. Karrer FM, Flannery AM, Nelson Jr. MD, McLone DG, Raffensperger JG. Anorectal malformations: evaluation of associated spinal dysraphic syndromes. J Pediatr Surg. 1988;23(1 Pt 2):45–48. 30. Rohrschneider WK, Forsting M, Darge K, Troger J. Diagnostic value of spinal US: comparative study with MR imaging in pediatric patients. Radiology 1996;200(2):383–388.