HEAD AND NECK SINUSES AND MASSES

chapter 75

HEAD AND NECK SINUSES AND MASSES Stephanie Acierno, MD, MPH  • ��� John �������� H. T. ������� �������������������� Waldhausen, MD

of the head and neck in children can be L esions subdivided by etiology as resulting from infection, trauma, or neoplasm, or being of congenital origin. The more common benign neoplasms, including hemangiomas, lymphangiomas, and cystic hygromas, are discussed in Chapter 74. Malignant neoplasms of childhood (e.g., neuroblastoma, lymphoma, and rhabdomyosarcoma), which occur as a primary or metastatic mass in the head and neck, lesions of the thyroid and parathyroid, and traumatic injuries of the head and neck, also are discussed in other chapters. In this chapter, common congenital head and neck malformations are described and inflammatory lesions are reviewed.

LESIONS OF EMBRYONIC ORIGIN Congenital cysts and sinuses that appear in the neck result from embryonic structures that have failed to mature or have persisted in an aberrant fashion.1,2 Successful treatment of a child with a mass or sinus in the head or neck requires accurate identification of the lesion as well as a planned course of therapy. Both diagnosis and therapy depend on a working knowledge of the embryologic origin and differentiation of the head and neck structures.3,4 This knowledge is particularly important because complete surgical resection of cartilaginous remnants, remnants of the branchial arch and cleft structures, and midline fusion abnormalities is imperative to avoid recurrence. Congenital lesions of the head and neck, in descending order of frequency, are thyroglossal duct cysts, preauricular pits and sinuses, branchial cleft anomalies, dermoid cysts, and median cervical clefts.

preschool-age children.1 Thyroglossal duct cysts also are common in young adults and, with the exception of thyroid goiter, are the most common midline neck masses in this age group.6

Embryology The embryogenesis of the thyroglossal duct is intimately involved with that of the thyroid gland, the hyoid bone, and the tongue.7 The foramen cecum is the site of the development of the thyroid diverticulum.7 In the embryo, this structure develops caudal to the central tuberculum impar, which is one of the pharyngeal buds that leads to the formation of the tongue.7 As the tongue develops, the thyroid diverticulum descends in the neck, maintaining its connection to the foramen cecum. During this time, the hyoid bone is developing from the second branchial arch. The thyroid gland develops between weeks 4 and 7 of gestation and descends into its pretracheal position in the neck.8 As a result of these multiple events occurring simultaneously, the thyroglossal duct may pass in front of or behind the hyoid bone, but most commonly it passes through it. Usually, the duct disappears by the time the thyroid reaches its normal position by 5 to 8 weeks’ gestation.5,9 Thyroglossal duct cysts never have a primary external opening because the embryologic thyroglossal tract never reaches the surface of the neck.8 Usually the thyroglossal tract becomes obliterated. If it persists, a cyst can be located anywhere along the migratory course of the thyroglossal tract in the neck (Fig. 75-1). Occasionally, the cysts attach to the pyramidal lobe of the thyroid or may be intrathyroidal.10 Complete failure of migration of the thyroid results in a lingual thyroid, which develops beneath the foramen cecum at the base of the tongue.11 In this instance, no thyroid tissue is found in the neck.11

Thyroglossal Duct Cyst

Clinical Presentation

One of the most common lesions in the midline of the neck is a thyroglossal duct cyst. Thyroglossal duct remnants are found in 7% of the population, although few become symptomatic.4,5 Although they are embryonic in origin, it is rare for these lesions to be found in the newborn period.1 More commonly, they are noted in

Two thirds of thyroglossal duct anomalies are discovered within the first 3 decades of life.5 Classically, the thyroglossal cysts are located in the midline at or just below the hyoid bone (Fig. 75-2). Suprahyoid thyroglossal cysts must be distinguished from submental dermoid cysts and from submental lymph nodes.12 997

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section 8  n  SKIN AND SOFT TISSUES DISEASES

A B C D

E

F

Figure 75-1.  Thyroglossal duct cysts can be located anywhere from the base of the tongue to behind the sternum. A and B, Lingual (rare). C and D, Adjacent to hyoid bone (common). E and F, Suprasternal fossa (rare). (From Welch KJ, Randolph JG, Ravitch MM, et al [eds]: Pediatric Surgery, 4th ed. Chicago, Year Book Medical, 1986, p 549.)

Rarely, the cysts are suprasternal in location. The initial sign is usually a painless mass in the midline of the neck, with 66% found adjacent to the hyoid bone.9 On physical examination, the thyroglossal duct cyst is smooth, soft, and nontender. To distinguish this lesion from the more superficial dermoid lesion, one should palpate the lesion while the child sticks out his or her tongue. Owing to its attachment to the foramen cecum, the thyroglossal duct cyst does not fully

Figure 75-2.  A classic thyroglossal duct cyst located in the midline just below the hyoid bone. Markings on the neck represent the thyroid, cricoid and tracheal cartilages.

move when the tongue protrudes. This maneuver is more reliable than asking the child to swallow and determining whether the mass moves with swallowing. Owing to the communication to the mouth via the foramen cecum, thyroglossal cysts can become infected with oral flora. One third of patients will pre­ sent with a concurrent or prior infection and a fourth will present with a draining sinus from spontaneous or surgical drainage of an abscess.9 Some patients may present with a foul taste in the mouth from spontaneous drainage of the cyst via the foramen cecum. The preoperative evaluation for a patient with a suspected thyroglossal duct cyst should include a complete history and physical examination. Patients with findings suggestive of hypothyroidism should undergo thyroid function testing and additional imaging to exclude a median ectopic thyroid. The incidence of ectopic thyroid tissue in or near the duct is reported to be from 10% to 45%. Some clinicians have advocated preoperative thyroid scanning or ultrasonography to eliminate the possibility of an ectopic thyroid gland masquerading as a thyroglossal duct cyst.13-17 Ultrasonography appears to be very accurate and avoids the need for irradiation and possible sedation in younger children.16 The anatomic location also may be useful in differentiating cysts and ectopic thyroid. Ninety percent of ectopic thyroid tissue lies at the base of the tongue, and thyroglossal duct cysts are rarely found there. Abnormal thyroid function tests, a suggestive history, or a solid mass evident on an ultrasound image should prompt a preoperative thyroid scan to ensure the lesion is not the only thyroid gland present, which occurs in less than 1% to 2% of patients with thyroglossal duct cysts.9,15,18 If ectopic thyroid tissue is found, the management becomes controversial, but some clinicians suggest a trial of medical suppression to decrease the size of the mass.

Treatment Elective surgical excision is advised to avoid the complications of infection and because of the small risk (<1%) of cancer developing in the cyst.15 The cyst and its cephalad tract are completely excised to the base of the tongue (Fig. 75-3). In 1920, Sistrunk described excision of the central portion of the hyoid bone as necessary treatment to prevent cyst recurrence.19 The operation must include resection of the central portion of the hyoid bone.20,21 Several other studies have shown that multiple smaller tracts can connect through the hyoid bone to the floor of the mouth, requiring wide resection of tracts above the hyoid.20-22 If these suprahyoid tracts remain, the incidence of recurrence increases.23 The best chance for successful resection is adequate wide resection at the initial procedure.22 As for all neck surgery, the patient should be supine with the neck slightly hyperextended (Fig. 75-4). The thyroglossal cyst is exposed through a transverse incision. The cyst has a characteristic appearance that is distinctly different from that of thyroid tissue. The dissection should continue cephalad to the hyoid, resecting a block of tissue along the proximal tract. Transecting the hyoid is simplified by using angled scissors, similar to Potts scissors, or by using a ­

chapter 75  n  HEAD AND NECK SINUSES AND MASSES

Figure 75-3.  Complete excision of a previously infected thyroglossal duct cyst. Surrounding skin was removed because of changes related to a previous infection. Note the well-defined tract leading toward the hyoid bone and the floor of the mouth. The operation was completed by excising the central portion of the hyoid bone and suture ligating the tract.

side-cutting bone cutter. The base of the tract at the floor of the mouth is ligated with absorbable suture. The wings of the hyoid are not approximated. The incision is copiously irrigated, and the wound is closed in layers. If the floor of the mouth is entered inadvertently, this can be repaired with absorbable suture. Occasionally, the dissection may be made easier by having the anesthesiologist place his or her finger at the base of the child’s tongue to identify the cephalad extent of the dissection. With complete excision, including the central portion of the hyoid bone, the risk of recurrence is low, 2.6% to 5.0%.5,9,23,24 Risk factors for recurrence include simple cyst excision alone (recurrence rates of 38% to 70%), intraoperative cyst rupture, presence of a cutaneous component, and postoperative wound infections.5,9,25 As mentioned, the cyst is usually connected to the foramen cecum by single or multiple tracts that pass through the hyoid. On histologic examination, the duct lining is ­stratified squamous epithelium or ciliated ­ pseudostratified

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columnar epithelium, with associated mucussecreting glands.9 The cyst contains a characteristic glairy mucus. Less than 1% have malignant tissue, which is most often papillary thyroid carcinoma. Infected cysts or sinuses should be managed by initially treating the infection. The usual route of infection is via the mouth. Thus, the common organisms are Haemophilus influenzae, Staphylococcus aureus, and Staphylococcus epidermidis.9 Needle aspiration may be required to decompress the cyst and allow for identification of the organism, but formal incision and drainage should be avoided. This may seed ductal cells outside of the cyst and increase recurrence rates.9 If incision and drainage is required, the incision should be placed so that it can be completely excised during a formal Sistrunk procedure once the infection clears. If a solid mass is found during thyroglossal duct cyst excision, it should be sent for frozen section to exclude median ectopic thyroid. If it is normal thyroid tissue and there is additional functional thyroid tissue in the normal location, a Sistrunk procedure with excision of the mass should be performed.9 If there is no other thyroid tissue present, management is controversial. One option is to leave the tissue in situ or reposition it into the strap muscles. This is attempted to prevent the patient from becoming permanently hypothyroid. However, most patients still require thyroid hormone therapy for hypothyroidism or to control the size of the ectopic thyroid. Because of this likely need for long-term therapy and possible malignant degeneration, some surgeons advocate complete excision of the ectopic thyroid tissue regardless of the presence of additional thyroid tissue.9

Remnants of Embryonic Branchial Apparatus Branchial anomalies comprise approximately 30% of congenital neck masses and can present as cysts, sinuses, or fistulas.5,26 They are equally common in males and females and present in childhood or early adulthood.

Embryology

Figure 75-4.  Positioning a child for a cervical operation. Hyperextension of the head with support under the shoulders and stabilization with a bean bag keeps the child in a stable position and facilitates exposure. The head of the bed should be elevated 30 degrees to decrease venous pressure in the neck.

During weeks 4 to 8 after fertilization, four pairs of well-developed ridges (branchial arches) dominate the lateral cervicofacial area of the human embryo.27 These four pairs are accompanied by two rudimentary pairs, which are analogous to the gill apparatus of lower forms.2,27 No true gill mechanisms are found in any stage of the human embryo. These pharyngeal arches and clefts are formed without a true connection between the outer ectodermal clefts and the inner endodermal pharyngeal pouches (Fig. 75-5). The mature structures of the head and neck are derivatives of several branchial arches and their intervening clefts.27,28 The branchial clefts and pouches are gradually obliterated by mesenchyme, but branchial cleft anomalies result if that process is incomplete.26 Each arch transforms during gestation into a defined anatomic pattern. Understanding this pattern and its relationship to normal neck structures is key in

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section 8  n  SKIN AND SOFT TISSUES DISEASES 1st branchial groove 2nd branchial arch

Pouch 2

Branchial arches 1 2 3 4

A

Cervical sinus

Tonsillar fossa

B

Sites of former openings of pharyngeal pouches

2

Tonsil

3

Pharynx

Cervical sinus 2nd, 3rd and 4th branchial grooves

Pouch 3 Pouch 4 Pouch 5 Esophagus

Internal branchial sinus

Skin of neck

Pouch 2 Pouch 3

External branchial sinus

Hyoid Figure 75-5.  A, The head and neck region of a 5-week-old embryo. B, Horizontal section through the embryo illustrating the relationship of the cervical sinus to the branchial arches and pharyngeal pouches. C, The adult neck region, indicating the former sites of openings of the cervical sinus and the pharyngeal pouches. The dotted lines indicate possible courses of branchial fistulas. D, The embryologic basis of various types of branchial sinuses. E, A branchial fistula resulting from persistence of parts of the second branchial cleft and the second pharyngeal pouch. F, Possible sites of branchial cysts and openings of branchial sinuses and fistulas. A branchial vestige also is illustrated. (From Moore KL: The Developing Human: Clinically Oriented Embryology. Philadelphia, WB Saunders, 1977.)

Pouch 1

Larynx

C Common carotid artery

Very rare type of internal branchial sinus

D

Area where auricular pits are commonly found

Tonsil

Sternocleidomastoid muscle

Palatine tonsil

Internal opening

Usual internal opening of fistula or sinus Branchial cyst

Pharynx Hyoid

Branchial vestige

Usual external opening of fistula or sinus

E

the diagnosis and treatment of these anomalies. Each anomaly is classified by the cleft or pouch of origin, which can be determined by the internal opening of the sinus as well as its relationship to nerves, arteries, and muscles. Careful attention to these relationships is necessary to prevent injury to surrounding tissues and ensure complete resection.26

Pathology Branchial anomalies are lined with either respiratory or squamous epithelium. Sinuses and fistulas usually have the former and cysts have the latter.26 One also can see lymphoid tissue, sebaceous glands, salivary tissue, or cholesterol crystals. Squamous cell cancer has been reported in adults, but it is rare and can be difficult to distinguish a primary branchiogenic lesion from a metastatic lesion from an occult primary lesion.5

F

Clavicle

Clinical Presentation Complete fistulas are more common than external sinuses. Both are more common than branchial cysts, at least during childhood.29,30 In adults, cysts predominate.29 By definition, all branchial remnants are truly congenital and are present at birth.30,31 Cysts are remnants of sinuses without an external opening and usually appear later in childhood than do sinuses, fistulas, and cartilaginous remnants, which are often found at birth.5,31 Sinuses have the persistence of the external opening only, whereas fistulas involve the persistence of the branchial groove with breakdown of the branchial membrane.5 Commonly, the tiny external opening of the fistula and the external sinuses remain unnoticed for some time. Spontaneous mucoid drainage from the ostium along the border of the ­ sternocleidomastoid

chapter 75  n  HEAD AND NECK SINUSES AND MASSES

usually heralds its presence and initiates the parent’s concern and the reason for the child’s referral. The first clinical presentation may be an infected mass as a result of the inability of the thick mucoid material to drain spontaneously. Infection is, however, less common in fistulas and external sinuses than in cysts.1 The cutaneous openings are occasionally marked by skin tags or cartilage remnants. The tract itself may be palpable as a cord-like structure ascending in the neck when the child’s neck is hyperextended and the skin is taut. Compression along the tract may produce mucoid material exiting from the ostium. The evaluation of these lesions starts with a thorough history and physical examination. Palpating the tract and observing the mucoid discharge can be confirmatory. Although colored dye or radiopaque material may be injected to delineate the tract, these manipulations generally are unnecessary. Upper endoscopy can be helpful to locate the pharyngeal opening. Both the pyriform sinus and tonsillar fossas should be examined. Cysts may be more difficult to diagnose. They lie deep to the skin along the anterior border of the sternocleidomastoid muscle.1 They can usually be distinguished from cystic hygromas, which are subcutaneous and can be transilluminated. Ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) can help define the lesion and can be particularly helpful in narrowing the differential diagnosis, but CT is most often used and can demonstrate a fistula in 64% of cases.32 A barium esophagogram has 50% to 80% sensitivity for third and fourth branchial fistulas.33 Whereas fine-needle aspiration is necessary in adults to rule out metastatic carcinoma, it is not necessary in children, and incisional biopsy should be avoided.26

Treatment The goal of treating all congenital neck sinuses, cysts, and fistulas is usually complete excision, done electively, when no inflammation is present.34 Timing of resection is controversial, with some advocating for early resection to prevent infection while others support waiting until 2 or 3 years of age.26,35,36 As with thyroglossal duct cysts, if the lesion is infected at clinical presentation, antibiotic therapy and warm soaks to encourage spontaneous drainage of mucoid plugs should precede definitive excision. Approximately 20% of lesions will have been infected at least once before surgery.35 Attempts at complete excision in an inflamed, infected field increase the risk of nerve injury and incomplete resection. Aspiration or a limited incision and drainage procedure is sometimes necessary to resolve the infection. Complete surgical excision is delayed until the inflammation subsides and the surrounding skin is supple. Endoscopic cauterization of fourth branchial cleft sinuses has been described either at the time of initial abscess drainage or 4 to 6 weeks later. Recurrence with this technique seems to be uncommon.37 Surgical resection is performed under general anesthesia with the patient positioned as shown in Figure 75-4. A small transverse elliptical incision is made

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around the external opening and deepened beneath the cervical fascia. The initial dissection is along the inferior border of the incision so that the ascending tract is identified from below and is not injured. Placement of a 2-0 or 3-0 monofilament suture or probe within the tract can facilitate this dissection. Dissection proceeds cephalad, staying on the tract until visualization of the most superior portion of the tract becomes difficult. At this level, a second, more cephalad, parallel “stair step” incision or extension of the original incision may be necessary for adequate exposure. If a second, more cephalad incision is needed, the tract is pulled subcutaneously through the second incision and the dissection is continued cephalad between the bifurcation of the carotid artery to the point where the tract inserts into the pharynx. The fistula is suture ligated with absorbable suture material. The ��������� incision� is closed in layers with absorbable sutures. No drains are needed if resection is complete. Recurrences are rare and imply that a portion of the epithelium-lined tract was overlooked. The incidence of recurrence is higher in cases of previously infected lesions. The specific embryology, anatomic presentation, and treatment for each type of branchial anomaly will now be discussed.

First Cleft Anomalies The first branchial arch forms the mandible and contributes to the maxillary process of the upper jaw.28,31,38 Abnormal development of the first branchial arch results in a host of facial deformities, including cleft lip and palate, abnormal shape or contour of the external ear, and malformed internal ossicles.28,31 The first branchial cleft contributes to the tympanic cavity, eustachian tube, middle ear cavity, and mastoid air cells. Microtia and aural atresia occur with failure of the first branchial cleft to develop.27,28 First branchial anomalies are rare and account for less than 1% of branchial cleft malformations.26 Cysts are seen as swellings posterior or anterior to the ear or inferior to the earlobe in the submandibular region. External openings, if found, are located inferior to the mandible in a suprahyoid position. One third open into the external auditory canal.6 The tract may be intimately associated with, or course through, the parotid gland. This and the proximity of the seventh cranial nerve make resection difficult, particularly in the younger patient who is likely to have a tract deep to the facial nerve.32 First cleft anomalies are classified as type I or type II (Figs. 75-6 and 75-7).5,26 Type I lesions are duplications of the external auditory canal, have ��������������������������������������������������� only ectoderm, course lateral to the facial nerve, and present as swellings near the ear. Type II consist of both mesoderm and ectoderm, can contain cartilage, pass medial to the facial nerve, and present as swellings inferior to the angle of the mandible or anterior to the sternocleidomastoid in a preauricular, infra-auricular, or postauricular position. First branchial anomalies are more common in females than males and are often misdiagnosed, leading to delay in excision.39 Presentation can include cervical, parotid, or auricular signs.

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section 8  n  SKIN AND SOFT TISSUES DISEASES

EAC

FBA

Facial n. Parotid

Figure 75-6.  Type I first branchial cleft anomaly (FBA). Note that the anomaly, located in the parotid gland, has no connection to the external auditory canal (EAC). (From Mukherji SK, Fatterpekar G, Castillo M, et al: Imaging of congenital anomalies of the branchial apparatus. Neuroimaging Clin North Am 10:75-93, 2000.)

EAC

Parotid

Facial n.

FBA

Figure 75-7.  Type II first branchial cleft anomaly (FBA). The anomaly connects with the external auditory canal (EAC) and extends deep into the parotid gland. (From Mukherji SK, Fatterpekar G, Castillo M, et al: Imaging of congenital anomalies of the branchial apparatus. Neuroimaging Clin North Am 10:75-93, 2000.)

Cervical signs include drainage from a pit-like depression at the angle of the mandible. Parotid signs result from rapid enlargement due to inflammation. Auricular signs can consist of swelling or otorrhea. Resection of first arch anomalies often requires at least partial facial nerve dissection and superficial parotidectomy. It is important to resect any involved skin or cartilage of the external auditory canal (Fig. 75-8). If it extends medial to the tympanic membrane, a second procedure may be necessary to remove the medial component. Tracts that go to the middle ear are more likely to travel deep or split around the facial nerve.39 Recurrence is common, and more than two procedures are often required for complete resection.40 Each repeat surgery places the facial nerve at greater risk from prior scarring, emphasizing the importance of complete resection at the first attempt.26

Second Cleft Anomalies The second arch forms the hyoid bone and the cleft of the tonsillar fossa.1,2 The second pouch gives rise to the tonsillar and supratonsillar fossa.26 The external ostium of the second branchial cleft is along the anterior border of the sternocleidomastoid muscle, ­generally at the junction of the lower and middle thirds.29 Because of its embryonic origin, the second cleft tract penetrates platysma and cervical fascia to ascend along the carotid sheath to the level of the hyoid bone. Remnants may be found anywhere along this course. The residual tract then turns medially between the branches of the carotid artery, behind the posterior belly of the digastric and stylohyoid muscles, and in front of the hypoglossal nerve to end in the tonsillar fossa (Fig. 75-9).29 Although the internal opening can be anywhere in the nasopharynx or oropharynx, it is most commonly found in the tonsillar fossa. Figure 75-10 demonstrates the four types of second arch anomalies. Type I anomalies lie anterior to the sternocleidomastoid muscle and do not come into contact with the carotid sheath. Type II lesions are the most common, passing deep to the sternocleidomastoid and anterior or posterior to the carotid sheath. Type III anomalies pass between the internal and external carotid arteries, ending adjacent to the pharynx. Type IV lesions are medial to the carotid sheath adjacent to the tonsillar fossa. Second branchial cleft anomalies represent 95% of all branchial cleft anomalies. About 10% of second branchial remnants are bilateral.29 These anomalies commonly present as a fistula or cyst in the lower, anterolateral neck. Fistulas are commonly diagnosed in infancy or childhood after presenting with chronic drainage from an opening anterior to the sternocleidomastoid muscle in the lower third of the neck. Cysts usually present during the third to fifth decades of life with an acute increase in size after an upper respiratory tract infection.5,26 The dissection of the tract follows the course as described above with care taken during the resection to protect the spinal accessory, hypoglossal, and vagus nerves. A finger or bougie in the oropharynx can help identify the opening in the

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*

Figure 75-8.  A, This young child presented with drainage from a first branchial cleft fistula. The ostium is marked with an arrow. B, In the operative photograph, the fistula has been dissected from its external opening (arrow) and is seen progressing toward the external auditory canal. The left ear (asterisk) has been elevated to improve visualization.

A

B

tonsillar fossa. The tract must be carefully ligated at this entry point.

Third and Fourth Cleft Anomalies Third and fourth branchial anomalies are rare. The third and fourth pouches form the pharynx below the hyoid bone; thus, these anomalies enter into the pyriform sinus. The third cleft migrates lower in the neck to form the inferior parathyroid glands and the thymus.7,29 The descent of the fourth cleft stops higher in the neck to form the superior parathyroid glands. The fourth pouch has added significance because its ventral portion develops into the ultimobranchial body, which contributes thyrocalcitonin-producing parafollicular cells to the thyroid gland.7 It is unusual to find cysts and sinuses from the third branchial cleft.2,28 When found, they are in the same area as those of the second cleft but ascend posterior to the carotid artery rather than through the bifurcation (Fig. 75-11).28 The fistula pierces the thyrohyoid membrane and enters the pyriform sinus. Fourth branchial fistulas are difficult to differentiate from other associated anomalies. Also, fourth pouch cysts are highly unusual and must be differentiated from laryngoceles. These tracts originate at the apex of the pyriform sinus, descend beneath the aortic arch, and then ascend anterior to the carotid artery to end in the vestigial cervical sinus of His (Fig. 75-12).41 Other anomalies arising from the third and fourth branchial pouches may appear as cystic structures in the neck. Thymic cysts may occur as a result of incomplete degeneration of the thymal pharyngeal duct or of progressive cystic degeneration of epithelial remnants of Hassall corpuscles.41 Most are found on the left side of the neck. Parathyroid cysts may be

First Branchial Cyst & Fistula

Second Branchial Fistula Third Branchial Fistula Figure 75-9.  A child with a cleft lip and remnants of the first three branchial systems. Note the important relation to the sternocleidomastoid muscle and the fistula’s origin. (From Welch KJ, Randolph JG, Ravitch MM, et al [eds]: Pediatric Surgery, 4th ed. Chicago, Year Book Medical, 1986, p 543.)

located anywhere around the thyroid gland or in the mediastinum. These are usually not associated with biochemical abnormalities, although reports of hyperparathyroidism secondary to functioning cysts have been seen. The etiology of these cysts is not clear, but they may be embryologic remnants of third and fourth branchial pouches or may represent cystic

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section 8  n  SKIN AND SOFT TISSUES DISEASES G H C

P

M

A M M

B

M

C

P

C

C

P

Figure 75-11.  Third branchial cleft anomaly. The cyst (C) is posterior to the sternocleidomastoid muscle, and the tract ascends posterior to the internal carotid artery. It then passes medially between the hypoglossal (H) and glossopharyngeal (G) nerves. It pierces the thyroid membrane (M) to enter the pyriform sinus. (From Mukherji SK, Fatterpekar G, Castillo M, et al: Imaging of congenital anomalies of the branchial apparatus. Neuroimaging Clin North Am 10:75-93, 2000.)

H

C

H

M

C

P

C

D Figure 75-10.  Types I to IV second branchial cleft anomalies. A, Type I: the cyst (C) is superficial to the sternocleidomastoid muscle (M). B, Type II: the cyst is adjacent to the carotid sheath. C, Type III: the cyst passes between the internal and external carotid arteries to the lateral wall of the pharynx (P). D, Type IV: the cyst is deep to the carotid sheath abutting the pharynx. (From Mukherji SK, Fatterpekar G, Castillo M, et al: Imaging of congenital anomalies of the branchial apparatus. Neuroimaging Clin North Am 10:75-93, 2000.)

degeneration of adenomas or gradual enlargement of microcysts.41 Both third and fourth cleft lesions can present at any age. In the neonate, both can present as tracheal compression or airway compromise owing to rapid enlargement. They can also present as cold nodules within the thyroid or as a thyroid abscess. Other initial presentations include recurrent upper respiratory tract infections or neck pain. Surgical therapy for third and fourth arch anomalies is similar to that for anomalies of the second arch, with a few notable exceptions. Endoscopy should be used to find the pyriform sinus entry point to allow cannulation of the tract to aid with dissection. Fourth arch anomaly resections require ipsilateral

C

Figure 75-12.  Fourth branchial cleft anomaly. The cysts (C) are located anterior to the aortic arch on either side. The tract hooks either the subclavian artery or the aortic arch, depending on the side, and ascends to loop over the hypoglossal nerve (H). (From Mukherji SK, Fatterpekar G, Castillo M, et al: Imaging of congenital anomalies of the branchial apparatus. Neuroimaging Clin North Am 10:75-93, 2000.)

­ emithyroidectomy for complete excision, and partial h resection of the thyroid cartilage may be necessary to expose the pyriform sinus.42

Preauricular Pits, Sinuses, and Cysts Embryology Preauricular pits, cysts, and sinuses are not of true branchial cleft origin.43 They represent ectodermal inclusions, which are related to embryonic ectodermal mounds (auditory hillocks) that essentially form the auricles of the ear.28,44 The sinuses are often short

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and end blindly. They never connect internally to the external auditory canal or eustachian tube.43 They characteristically end in thin strands that blend with the periosteum of the external auditory canal. Some authors propose that they are a marker of teratogenic exposure.44 Preauricular cysts are located in the subcutaneous layer superficial to the parotid fascia and may seem deeper if they become infected. These cysts and sinuses are lined with stratified squamous epithelium. They do not contain hair-bearing follicles, owing to their origin from the ectoderm associated with external ear formation.34

Clinical Presentation The estimated incidence of preauricular sinuses is 0.1% to 0.9% in the United States and as high as 4% to 10% in Africa.44 These cysts and sinuses are commonly noted at birth and are more common on the right side.44 The parent may remark about the familial and bilateral nature of these lesions.29 Preauricular sinuses usually do not drain. In those situations, excision is not required. However, parents may report that sebaceous-like material drains from the sinus. The presence of drainage is an indication for surgical excision. Sinuses that drain are often connected to subcutaneous cysts that have an increased likelihood of staphylococcal infection. Ideally, these lesions should be completely excised before becoming infected (Fig. 75-13). Prior infection increases the difficulty of complete surgical excision, which increases the risk of recurrence.

Treatment Complete surgical excision of the sinus tract and subcutaneous cyst to the level of the temporalis fascia is the treatment of choice in the uninfected draining sinus. It is important to avoid rupture of the sinus and to perform a complete excision to decrease the risk of recurrence.45 If infection supervenes, the lesion is treated with antibiotics and warm soaks to encourage drainage and control of the surrounding inflammation. Occasionally, as with infected branchial cysts, incision and drainage or needle aspiration may be required to control the infection. Surgical excision is often done through an elliptical incision with a small, chevron-shaped skin flap surrounding the sinus. The cyst is then dissected from the subcutaneous tissue and removed in its entirety.43 The cyst or sinus may have multiple branches, making complete resection difficult. Removal of a small bit of adjacent cartilage reduces the risk of missing one of these branching tracts.44 The incidence of recurrence is as high as 40%, owing to these multiple branches. As a result, some clinicians have advocated an extended preauricular incision to enhance exposure.45 Postoperative wound infection also is common.

Branchio-oto-renal Syndrome Branchio-oto-renal syndrome (Melnick-Frazier syndrome) is an autosomal dominant disorder that can occur with branchial fistulas and preauricular pits.

Figure 75-13.  An infected preauricular cyst. The pit anterior to the helix is difficult to see. Note the swelling and skin changes anterior to the tragus. Preauricular sinuses that drain sebaceous material should be excised electively. Warm compresses and antibiotics allowed the inflammation to diminish. The cyst and sinus were then completely excised.

It occurs in 2% of profoundly deaf students and has been mapped to chromosome 8q13.3, which has roles in cochlear and vestibular development and renal morphogenesis.46 The typical phenotype includes cup-shaped pinnas; preauricular pits; branchial fistulas; conductive, sensorineural, or mixed hearing impairment; and renal anomalies ranging from mild hypoplasia to agenesis. Hearing loss and preauricular pits are the most common associations, and 50% of patients have branchial cleft fistulas.46

Dermoid and Epidermoid Cysts Dermoid cysts embryologically represent ectodermal elements that either were trapped beneath the skin along median or paramedian embryonic lines of fusion or failed to separate from the neural tube.47-50 Dermoids are differentiated from epidermoids histologically by the accessory glandular structures found in dermoids.47 Dermoids contain sebaceous glands, hair follicles, connective tissues, and papillae.47 Both contain sebaceous material within the cyst cavity. Most dermoid or epidermoid cysts are diagnosed before the patient is 3 years of age.5 The most common location for dermoids in children is along the supraorbital palpebral ridge (Fig. 75-14). This lesion commonly appears as a characteristic swelling in the corner of the eyebrow and is most commonly first noticed at birth or within the first 1 to 3 months of life. Although commonly attached to the underlying bony fascia, this lesion is movable and nontender. Occasionally, the mass may be dumbbell shaped and penetrate through the orbital bone. Dermoids may

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capsule and avoid intraoperative rupture to decrease the risk of recurrence. Infection is possible secondary to repeated local trauma. Malignant degeneration of dermoids also is possible but rare.23 Complete surgical excision is curative.

Midline Cervical Clefts

Figure 75-14.  This infant presented with the classic finding of a dermoid cyst located along the supraorbital palpebral ridge (arrow).

occur along the midline or atypical locations such as the medial orbital wall, nose, floor of the mouth, or submental and submaxillary areas.51 Midline cysts can be confused with midline thyroglossal duct cysts. Dermoids, however, are more superficial and remain mobile when the tongue is forcibly protruded and will lack a deep-seated tract to the hyoid bone or other neck structures. Nasal dermoids may pre­ sent as a cyst or sinus anywhere from the glabella to the base of the columella.51 Any midline scalp lesion suspected of being a dermoid should undergo preoperative radiographic evaluation to evaluate for intracranial extension. This is especially important for nasal dermoids, which have been reported to extend to the cribriform plate in 12% to 45% of cases.51 The best way to evaluate for deep extension of a midline lesion is controversial. Both CT and MRI may be used in a complementary fashion, with CT better for evaluating bony abnormalities and MRI better for defining soft tissue structures. Some clinicians argue that CT alone is adequate; however, false-negative results have been reported.51 Dermoids and epidermoid cysts gradually increase in size owing to the accumulation of sebum.49 Infection is rare, but the cysts can rupture, resulting in granulomatous inflammation.5,49 Fine-needle aspiration may also be helpful in distinguishing an infected thyroglossal duct cyst from a ruptured dermoid.49 Surgical excision is the treatment of choice for all dermoids and epidermoids, especially those that are symptomatic, enlarging, or have ruptured. This has been most commonly performed as an open ­operation, although increasing experience with removing these lesions is accruing by using endoscopic minimally invasive techniques.52 Proponents of the open technique report good cosmetic results with minimal complications, whereas early reports with the endoscopic technique have reported a few partial facial nerve injuries especially early into the surgeon’s learning curve.53 It is important to completely remove the

Midline cervical clefts are rare congenital cervical anomalies that present at birth as a cutaneous ulceration with overhanging skin or cartilage tag in the anterior lower midline of the neck (Fig. 75-15). There may be a tract that extends downward into the skin connecting to the sternum or mandible, or it can end blindly. The embryologic origin is unknown but thought to be a “mesodermal fusion abnormality” involving the branchial arches.9 Most are sporadic but can be found with cleft abnormalities of the tongue, lower lip, or mandible. Early surgical excision at the time of diagnosis is recommended to avoid neck contractures or growth deformities of the sternum or mandible. This is achieved through complete excision of the skin lesion and the subcutaneous sinus to reduce the rate of recurrence. Stairstep incisions or a series of Z-plasty incisions may be required.9

Torticollis Etiology Torticollis in childhood may be congenital or acquired. Congenital torticollis resulting from fibrosis and shortening in the sternocleidomastoid muscle is the most common type.54-56 The shortening of the

Figure 75-15.  Congenital midline cervical cleft. (From Foley DS, Fallat ME: Thyroglossal duct cysts and other congenital midline cervical anomalies. Semin Pediatr Surg 15:70-75, 2006.)

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s­ ternocleidomastoid muscle characteristically pulls the head and neck to the side of the lesion. The resulting “mass” represents the fibrous tissue palpable within the muscle. The etiology of this “fibrous tumor” is debatable.57 The significant incidence of breech presentations and other abnormal obstetric positions has been used to support both the injury and the tumor etiology. Those who favor tumor see the abnormal presentation as the result of the fixed abnormal head position, whereas those who favor trauma see the difficult extraction as the cause of injury.55,58 No single theory completely explains this condition. The etiology of acquired torticollis includes cervical hemivertebra and imbalance of the ocular muscles. In children in whom no identifiable muscular etiology is found, a high likelihood exists of Klippel-Feil anomalies or other neurologic disorders as the cause.59 Acquired torticollis also should raise the suspicion of otolaryngologic infection, gastroesophageal reflux (Sandifer’s syndrome), or the possibility of a neoplastic condition as the underlying cause.60,61 Pathologically, the basic abnormality in congenital torticollis is endomysial fibrosis—the deposition of collagen and fibroblasts around individual muscle fibers that undergo atrophy.57 The sarcoplasmic nuclei are compacted to form “muscle giant cells,” which appear to be multinucleated. The severity and distribution of fibrosis differ widely from patient to patient. Some cases of fibrosis occur bilaterally. The fact that mature fibrous tissue is present even in the neonate suggests that the disease begins well before birth and probably does not result from a difficult delivery.

Diagnosis In a series of 100 infants with torticollis, 66% had a “tumor” in the muscle and the other 34% had fibrosis but no tumor.24,62 A more recent series of 624 cases from China noted only 35.4% with a tumor.63 In the typical case, the mass is not found in the neonatal period but is noted at the first “well-baby” checkup, some 6 weeks after birth. The infant has the characteristic posture, with the face and chin rotated away from the affected side and the head tilted toward the ipsilateral shoulder. Acquired torticollis may develop at any age. It is important to keep in mind the various causes of the acquired lesion. Its appearance depends on the severity of the lesion, the distribution of the fibrosis, and the child’s growth pattern. With time, facial and cranial asymmetry develop and a notable flattening of the facial structures on the side of the lesion occurs. This may become irreversible by age 12 years, although there have been reports of excellent results when the surgical procedure is performed after age 10 years.64,65

Treatment Experience with this condition has shown that 80% to 97% of affected infants do not require operative treatment.63,64 The key to successful treatment is early recognition and prompt physical therapy.56,66 The longer the shortening of the muscle persists, the more facial and cranial asymmetry develops, and the more the

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deeper cervical tissues become involved in the process. Ultrasonography may be used not only as a diagnostic tool but also to help determine which children may be more likely to need surgical therapy. In a study from China, the cross-sectional as well as longitudinal extent of fibrosis in the sternocleidomastoid muscle correlated well with the need for surgical intervention.67 In most instances, complete correction can be achieved by early range-of-motion and stretching exercises and positional changes with the infant in the crib. The parents should be taught to perform these exercises with the infant multiple times each day. One parent holds the child’s shoulder down against a firm surface, and the other rotates the head toward the opposite shoulder. When the child’s head is rotated toward the opposite shoulder, the muscle is gently kneaded along its entire course. Often one parent can accomplish the stretching exercises by placing the infant on his or her lap, turning the infant’s head, and gently extending the head and neck over the parent’s knees. An additional maneuver is rearranging the infant’s room, changing objects in the crib, and encouraging the infant to look toward the side opposite the involved muscle. One study showed a mean duration of 4.7 months for successful nonoperative resolution.68 Some clinicians have used botulinum toxin injections in select patients who have failed to improve after 6 months of aggressive physical therapy, avoiding surgery in 74% to 95% of subjects.69,70 Some clinicians have suggested that the criterion for operation, regardless of age, is the development of facial hemihypoplasia.66 In children with significant torticollis, facial hemihypoplasia is invariably present, not always with a linear relation between the two conditions.66 The muscle can be divided anywhere, but transection in the middle third, through a lateral collar incision, is the simplest and provides the most aesthetically acceptable scar.66,71 Through this incision, one can divide the fascia colli of the neck, which is often tight and may need to be divided anteriorly as far as the midline and posteriorly to the anterior ­border of the trapezius. Intensive physiotherapy, including full rotation of the neck in both directions and full extension of the cervical spine, is instituted as soon as possible. Occasionally, in an older child, a splint is used to provide overcorrection and stretching of the muscle.66,71

INFLAMMATORY LESIONS Cervical Adenopathy Enlarged cervical lymph nodes are by far the most common neck masses in childhood. In most instances they are the result of nonspecific reactive ­hyperplasia.1 The etiology is often viral or is related to an upper respiratory tract or skin infection. The adenitis resolves spontaneously. Many patients are initially seen with bilateral enlarged nodes. Because the anterior cervical nodes drain the mouth and pharynx, almost all

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Figure 75-16.  Acute suppurative cervical adenitis. Skin is shiny and taut over the centralized abscess cavity.

fluctuant, eventually leading to thinning of the ­overlying skin and abscess formation. Needle aspiration can be both diagnostic and therapeutic. Aspiration of the purulent material confirms the diagnosis. The material obtained can be cultured (Fig. 75-17). Frequently, needle aspiration and drainage of the purulent material coupled with judicious antibiotic therapy may alleviate the necessity of formal incision and drainage. Occasionally, repeated aspirations may be necessary. If the child appears toxic or is quite young, hospitalization and intravenous antibiotics, including a βlactamase–resistant antibiotic, may be helpful, but ­formal incision and drainage is often required. The node can be incised and the cavity packed loosely with a Silastic drain. The parent can be taught to perform irrigations through the drain, which encourages drainage of the residual debris. Usually, apparent improvement is evident in 2 to 3 days, although antibiotic therapy should be continued for 10 days. Complete resolution of the adenopathy may take weeks.

Chronic Lymphadenitis upper respiratory and pharyngeal infections have some effect on the anterior cervical nodes. Enlarged cervical lymph nodes are frequently palpable in children between ages 2 and 10 years. Palpable nodes are uncommon in infants. A mass in a child younger than 2 years old is more likely to be a cystic hygroma, thyroglossal duct cyst, dermoid cyst, or branchial cyst. The mass can often be diagnosed on clinical findings.72 Because the head contains so many structures through which bacteria or viruses may enter the body, the cervical lymph nodes frequently become involved in these cervicofacial infections and inflammatory diseases. Cervical nodes also may be the first clinical manifestations of various tumors, particularly those of the lymphoma group.1 The most frequent inflammatory lesion of the cervical lymph nodes is suppurative lymphadenitis (Fig. 75-16). Others of importance are cat-scratch disease, atypical mycobacterial lymphadenitis, and tuberculous lymphadenitis. Less common but important considerations in the differential diagnosis of cervical adenitis include Kawasaki’s disease and acquired immunodeficiency syndrome (AIDS).

Children occasionally have impressively enlarged nodes that do not seem to be acutely infected. The nodes are not as inflamed or as tender as those in acute bacterial adenitis. Progression to fluctuation is unlikely. The child with this type of lymphadenopathy must be evaluated for tuberculosis, atypical mycobacterial infection, and cat-scratch disease. Most children should receive a full 2-week course of an oral antistaphylococcal antibiotic. The same physician should examine the child on a number of occasions to assess the results of therapy. A single dominant lymph node present for longer than 6 to 8 weeks that has not responded to appropriate antibiotic therapy, should be completely excised, fully cultured, and submitted for histologic examination to exclude the diagnosis of malignancy. Nodes present in the supraclavicular space

Acute Suppurative Cervical Lymphadenitis The most common cause of acute lymphadenopathy is a bacterial infection arising in the oropharynx or elsewhere in the drainage area.73 The most common organisms are penicillin-resistant Staphylococcus aureus and Streptococcus hemolyticus, although cultures of the pus often yield a mixture of both or prove to be sterile.73 Staphylococcus may be more prevalent in infants.74 Anaerobes, although common in the oropharynx, are not common pathogens in cervical adenitis. The ­diagnosis is usually apparent. Fever is variable and ­usually mild. Initial treatment with antibiotics is often followed by resolution without suppuration. Without treatment, the node often enlarges and becomes

Figure 75-17.  Aspiration of purulent material confirms the diagnosis of suppurative lymphadenitis. Frequently, repeated aspirations may be necessary to remove the majority of debris and can often obviate the need for formal incision and drainage.

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and posterior triangle tend to be more of a concern for malignancy than those found in the submandibular or anterior triangle.

Mycobacterial Lymphadenitis Clinical Presentation The prevalence and the relative incidence of infections caused by different mycobacteria vary with the success of preventive health measures in particular populations.75 In developed countries, bovine mycobacteria have been eliminated from milk. Most mycobacterial lymphadenitis is caused by the atypical mycobacteria of the Mycobacterium avium-intracellulare-scrofulaceum (MAIS) complex.75 Internationally adopted terminology defines this group of 10 to 15 mycobacteria, which produce a specific and localized form of lymphadenitis.20,47,75 The portal of entry is primarily through the mucous membranes of the pharynx. Lymphadenitis resulting from infection with M. tuberculosis is thought to be an extension of a primary pulmonary infection and usually involves the supraclavicular nodes.76 Infection with the atypical strains usually involves higher cervical nodes, most commonly the submandibular or submaxillary.76 This finding is consistent with the etiology being a primary infection and not pulmonary disease. Infection is most commonly seen between ages 1 and 5 years; occurrence before age 1 year is rare. The disease involves unilateral nodes, and dissemination is rare. Atypical mycobacteria enter from the environment and are not contagious, although the reservoir may be the mouth and oropharynx of apparently healthy children.74 Person-to-person spread of disease has not been documented, and isolation is not necessary. Infection with atypical mycobacteria is generally limited to the lymph nodes. Pediatric patients with atypical mycobacterial lymphadenitis are usually asymptomatic. The nodes are usually nontender. Spontaneous regression of the atypical lymph node infection may occur but is likely to lead to breakdown of the nodes, resulting in sinus or fistula formation. Children with tuberculous scrofula usually are symptomatic. Most have pulmonary tuberculosis when the diagnosis is made.77 It is rare for the infection to progress from cervical adenopathy to pulmonary disease if the initial chest radiographs are clear. Degeneration of nodes with abscess and fistula formation is unusual.

Diagnosis In children, tuberculous or atypical mycobacterial lymphadenitis presents as a clinical picture of chronic lymph node hypertrophy.78 Pulmonary tuberculosis on chest radiograph helps to identify the cause of the cervical swelling. Patients with MAIS usually have a normal chest radiograph. Skin testing helps differentiate these diseases. All children with tuberculosis should show positive test results to second-strength purified protein derivative (PPD). Children with ­atypical mycobacterial infection have either a negative or a doubtful skin test. If the initial PPD is inconclusive, second-strength PPD may help ­ confirm the

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mycobacterial etiology. A history of familial exposure to tuberculosis should suggest tuberculosis as more likely than atypical mycobacteria. Although specific skin tests for atypical mycobacteria often provide positive results, it is difficult to obtain the appropriate antigen. Final diagnosis may depend on culture results or histopathology after excision of the involved nodes.79

Treatment It is important to distinguish tuberculous from MAIS lymphadenitis because the treatment is significantly different. In tuberculous infections, antituberculous chemotherapy is required, usually resulting in marked resolution of the lymphadenopathy within a few months. Chemotherapy is continued for 2 years.77 Surgical intervention in a human tuberculosis infection is confined to an excisional biopsy of a node if the diagnosis cannot be made on other grounds. Most children with tuberculous lymphadenitis respond well to chemotherapy with standard drugs. Treatment of MAIS infections is primarily surgical.80 Careful, thorough excision of the group of affected nodes (the one or two sentinel nodes) and adjacent smaller nodes is required. This procedure should ideally be performed before extensive ulceration of the overlying skin occurs. Standard chemotherapy for tuberculosis is of no value in MAIS infections except in patients in whom a draining sinus develops after primary excision of infected nodes.81 Children with atypical mycobacterial infection respond well to complete surgical excision without drug therapy. Some authors report successful treatment with antibiotics alone (e.g., clarithromycin, ethambutol, and rifampin) in patients whose lesions were too close to the facial nerve or other key structures.82

Cat-Scratch Disease The incidence of cat-scratch disease varies greatly in different parts of the world. In developed countries, cat-scratch disease is the most common cause of nonbacterial chronic lymphadenopathy.83 Bartonella henselae, a gram-negative rickettsial organism, is responsible for most cases of cat-scratch disease.84 The disease is usually transmitted via a superficial wound caused by a cat, dog, or monkey.85 A healthy kitten is the most frequent vector. The disease begins as a superficial infection or pustule forming in 3 to 5 days and is followed by regional adenopathy in 1 to 2 weeks. Generally, only one node is involved. Nodal involvement corresponds to the inoculation site and the nodes that drain it. The axilla is the most commonly involved area.1 The diagnosis can be made by a commercially available indirect fluorescent antibody test for detection of antibody. Histology findings are characteristic but not pathognomonic. Polymerase chain reaction studies for B. henselae on a fine-needle aspirate may be useful when the diagnosis is in question, although this technique is not readily available in all hospitals.86 Complete excision of the involved node may be needed to confirm the diagnosis. Patients ­usually have

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tender lymphadenopathy and few systemic symptoms. On rare occasions, complications include encephalitis, retinitis, and osteomyelitis. The delay between inoculation and subsequent lymphadenopathy can approach 30 days.85 Treatment of cat-scratch disease is most often symptomatic because the disease is usually self-limited. Lymphadenopathy resolves spontaneously over a period of weeks to months with only occasional suppuration. Specific antimicrobial therapy against B. henselae has not proved efficacious, although it is susceptible to many common antibiotics. Azithromycin, rifampin, ciprofloxacin, and tri­methoprim-sulfamethoxazole may be useful if ­antibiotics are needed.87,88

Lesions of the Salivary Glands Surgical lesions of the salivary glands in children are unusual. In this section we address benign and inflammatory conditions in these glands.

Ranula In children, prominent, glistening, cystic masses occasionally develop below the tongue in the floor of the mouth. These cystic lesions generally arise from the sublingual glands and are known as ranulas (Fig. 75-18).89 Most are simple cysts that result from the partial obstruction of the sublingual salivary duct. The traditional ranula is a simple cyst lined with salivary ductal epithelium. Occasionally, the sublingual duct can become completely occluded. The duct may ­rupture, which leads to the formation of a pseudocyst. The pseudocyst forms because amylase-­containing secretions extravasate and erode or “plunge” into the neck muscles. This leads to the condition known as “plunging ranula.”90,91 This lesion lacks a true epithelial lining.90

Many surgeons suggest marsupialization at the initial procedure for a simple ranula.92,93 By incising the cyst and draining the contents, the mass rapidly decreases in size. Suturing the epithelium back on itself allows the partially occluded duct to drain. Marsupialization alone has a fairly high recurrence rate, and complete resection or marsupialization with packing may be preferable.92,93 Concurrent resection of the ipsilateral sublingual gland has been shown to decrease the rate of recurrence (1.2% compared with 66%).93,94 Recent trials with picibanil (OK-432) similar to therapy for lymphangioma have been described with some success in Japan.95 The complex or plunging ranula requires a more extensive dissection into the neck to totally excise the pseudocyst and the atrophied sublingual gland.91 This may be accomplished using an intraoral approach but may require a cervical incision. Dissection may be tedious in this inflamed area because the hypoglossal and lingual nerves run beneath the sublingual gland and become entrapped in the mass.

Parotid Hemangioma This is the most common benign neoplasm affecting the major salivary glands and is seen most often in female infants at birth or within the first few months of life.96 It is usually confined to the intracapsular component of the gland and rarely involves the overlying subcutaneous tissues and skin. A surface sentinel lesion may be present. It appears as a spongy mass anterior to the ear. The diagnosis is usually evident on physical examination. Rarely is a cutaneous component present in the hemangioma. Growth may be rapid in the first few weeks of life. Ultrasonography is helpful, and MRI can be useful in establishing the diagnosis. Most parotid hemangiomas involute by age 4 to 6 years, and only 10% need surgical intervention. One series demonstrated that parotid hemangiomas, like other hemangiomas, respond to medical therapy with corticosteroids or interferon in 98% of cases, with surgical therapy being delayed until the involuting or involuted phase for reconstruction only.97 Surgical resection puts the seventh nerve at risk so it must be conducted with great care.

Sialadenitis

Figure 75-18.  A simple cystic ranula, located below the tongue, is arising from the sublingual glands.

Inflammation and swelling of the salivary glands are not common in children. Sialadenitis may appear as an acute suppurative infection, a chronic infection, or a granulomatous replacement of the gland. Acute suppurative sialadenitis is most frequently seen in infants. The organism most often involved is S. aureus, followed by Streptococcus and group D pneumococcus.98 The pathophysiology of chronic sialadenitis may involve duct ectasia, stricture, and sialolithiasis. Sialectasis, a saccular dilation of the small, intercalated ducts that connect acini with the striated ducts, is a common congenital abnormality of the gland. Sialolithiasis occurs much more commonly in the submandibular than in the parotid gland. Culture of material from the

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duct may not reveal pathogenic organisms. Recurrent bacterial infection without demonstrable obstruction is the primary problem in some cases.

Clinical Presentation Sialadenitis is characterized by episodes of pain that may last from 1 to 7 days. Swelling and pain are isolated to the anatomic distribution of the gland and do not involve the overlying skin and subcutaneous tissue. Secretions are thick and flocculent. Bilateral involvement may occur over time, although each acute episode tends to be unilateral.

Diagnosis Salivary gland abnormalities may follow diseases such as mumps. Tenderness may occur, with cystic or solid swelling of the gland. The pus may be seen draining from Warthin’s duct. Plain radiographs are useful in detecting radiopaque stones, which are seen four

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times more frequently in the submandibular than in the parotid gland.98 Sialography remains the definitive study for ductal abnormalities, although it is associated with some discomfort and may require general anesthesia in younger children. High-resolution ultrasonography may demonstrate ductal ectasia.98 CT has been used in children to evaluate vascularity and abscess formation. MRI may be useful in imaging the course of the facial nerve through the parotid gland.99 Incisional biopsy is rarely indicated. The utility of fineneedle aspiration is questionable.100

Treatment Antibiotics may be useful in both acute and recurrent sialadenitis. Nonspecific therapy with sialagogues, with massage of the gland, may be helpful. Sialolithotomy or dilation with removal of demonstrated calculi is usually curative. Radical surgical treatment is rarely necessary in children.