Richard Jh Smith

Localization of Usher syndrome type II to chromosome 1q

Usher syndrome is characterized by congenital hearing loss, progressive visual impairment due to retinitis pigmentosa, and variable vestibular problems. The two subtypes of Usher syndrome, types I and II, can be distinguished by the degree of hearing loss and by the presence or absence of vestibular dysfunction. Type I is characterized by a profound hearing loss and totally absent vestibular responses, while type II has a milder hearing loss and normal vestibular function. Fifty-five members of eight type II Usher syndrome families were typed for three DNA markers in the distal region of chromosome 1q: D1S65 (pEKH7.4), REN (pHRnES1.9), and D1S81 (pTHH33). Statistically significant linkage was observed for Usher syndrome type II with a maximum multipoint lod score of 6.37 at the position of the marker THH33, thus localizing the Usher type II (USH2) gene to 1q. Nine families with type I Usher syndrome failed to show linkage to the same three markers. The statistical test for heterogeneity of linkage between Usher syndrome types I and II was highly significant, thus demonstrating that they are due to mutations at different genetic loci.

Cystic fibrosis--an otolaryngologic perspective.

Cystic fibrosis (CF) is the most common lethal genetic disorder in white patients. The protean manifestations of the disease result from exocrine gland dysfunction and include chronically debilitating pulmonary and pancreatic compromise and clinically inconsequential (although diagnostically extremely important) sweat electrolyte abnormalities. The subject of this article is the otolaryngologic manifestations of the disease, based on a retrospective analysis of 450 cases. Nasal polyposis and sinusitis occurred in 10% and 11% of patients, respectively, and polypectomy was, after laparotomy, the most common surgical procedure these children underwent. The extent of intranasal surgery for polyposis was found to be inversely proportional to the recurrence rate. A simple polypectomy was relatively ineffective treatment; when performed in conjunction with a Caldwell-Luc and either an intranasal or extranasal ethmoidectomy, the recurrence rate was less than 13%. Otologic problems, found in 8% of patients, included chronic otitis media (2.5%) and acute otitis media (5.5%). Only five patients required pressure-equalizing tubes. Recent genetic advances of immense importance are also described. Although the basic gene defect has yet to be elucidated, by use of a technique known as restriction-fragment-linked polymorphism, the gene associated with CF has been found in the middle of the long arm of chromosome 7. By following gene markers closely associated with this gene, it is possible to do carrier tests within affected families and, if certain criteria are met, perform prenatal diagnosis. Eventual isolation and characterization of the gene will follow, hopefully making prevention possible and treatment more effective.

Current management of laryngeal and laryngotracheoesophageal clefts

Laryngeal and laryngotracheoesophageal clefts (L-LTEC) are uncommon anomalies in neonates that cause significant morbidity secondary to aspiration, pneumonia, and respiratory distress. Other anomalies of development, such as esophageal atresia and tracheoesophageal fistula (EA-TEF), are observed in 20% of patients with L-LTEC and often confuse the radiographic and clinical picture. Repair of L-LTEC depends on the length and location of the cleft, associated anomalies, and concurrent systemic illness. For type I L-LTEC, endoscopic repair occasionally is possible with microsurgical instrumentation. With types II to IV L-LTEC, an open approach must be used. Tracheotomy is a universal requirement, often for extended periods of time. Reported here is our experience with four cases of L-LTEC managed over the past 7 years at Texas Childrens Hospital.

Head and neck manifestations of neurofibromatosis

Neurofibromatosis is a neurocutaneous systemic disease that occurs in 1:2500 to 3300 live births. Prevalence figures have shown it to be as common as cystic fibrosis or Downs syndrome and more than twice as common as muscular dystrophy. In this study, our experience with 257 cases of neurofibromatosis seen since 1972 is reviewed. Intracranial, bony, and extracranial anomalies are described in the 223 patients (87%) who presented with, or ultimately developed, head and neck manifestations of the disease. The most common intracranial tumor was optic glioma, found in 35 patients (14%), 19 younger than 10 years of age. Acoustic neuromas were diagnosed in eight individuals (3%) and were bilateral in three. The most common skull anomaly was macrocephaly, noted 78 times (30%). Absence of the sphenoid wing occurred in 11 patients (4%) and 19 others (7%) had facial asymmetry due to other skull abnormalities. Extracranial manifestations included neurofibromas of the plexiform and nonplexiform type, Lisch nodules, and cafe‐au‐lait spots.

Lymphangioma. An otolaryngologic perspective

Lymphangiomas are relatively rare congenital hamartomas of the lymphatic system usually diagnosed in infancy and early childhood. Although the precise pathogenesis has not been clearly defined, abnormal development leads to formation of fluid-filled sinuses lined by vascular endothelium. In the head and neck, lymphangioma may encroach on vital structures and infiltrate surrounding tissues making complete surgical removal difficult. A number of children (n = 137) with lymphangioma have been treated at Texas Childrens Hospital from 1972-1985. In 45 (33%), the tumors were diagnosed at birth and in an additional 51 (37%), by two years of age. Commonly affected areas included the head and neck (45%), trunk (26%), and axilla (17%). Mediastinal involvement occurred in 4%. Surgical removal was the preferred treatment method and with complete removal the recurrence rate was 6%; known incomplete removal increased this rate to 35%. Although lymphangiomas are slow growing, early removal was preferable: recurrences increased as the time interval between tumor identification and surgical intervention lengthened. Size fluctuation with a history of infection, another unfavorable prognostic factor, also increased recurrence rate.

Craniocervical Necrotizing Fasciitis

Craniocervical necrotizing fasciitis (CCNF) is a severe, progressive bacterial infection of the cervical fascia. The most significant manifestations of this disease are extensive fascial necrosis with widespread undermining of the surrounding tissues and extreme systemic toxicity. We are adding three cases to the 29 previously reported cases of CCNF. We will discuss the regional anatomy, focusing on the relationship of the cervical fascial planes to vital structures. Available data suggest that CCNF is a synergistic infection produced in most instances by a combination of facultative anaerobic and obligate anaerobic organisms. Although antimicrobial therapy should provide broad-spectrum activity against mixed flora, treatment also includes aggressive excision and debridement of involved fascia, subcutaneous tissue, and necrotic skin.

Airway compression secondary to left atrial enlargement and increased pulmonary artery pressure

Although congenital cardiac defects are infrequently considered a cause of major airway compression in neonates and infants, patients with left-sided cardiac enlargement can develop compression of the left mainstem bronchus. This is a consequence of the intimate relationship of the trachea and left mainstem bronchus to the left atrium, left pulmonary veins and left pulmonary artery. If the mean pulmonary arterial pressure, mean left atrial pressure and carinal angle are increased, the likelihood of major airway compression is high.

Burkitt's lymphoma

Cancer is the second leading cause of death in children and, among cancers, lymphoma is the third most frequently diagnosed type. The majority of these are non-Hodgkins lymphomas (NHL). Although NHL have been grouped in a variety of confusing ways, recent research in cytogenetics and immunology, coupled with a better understanding of the normal pathways of lymphoid differentiation, has greatly lessened this confusion. Burkitts lymphoma (BL) is a type of B-cell NHL which is sub-classified as either endemic (African) or non-endemic (American). Kinetic studies have demonstrated a doubling time of only 24 h. As a result of this extremely rapid growth, symptomatic complaints occur early in the disease course. Structures contiguous to the primary become compressed and metabolic derangements occur. Signs of chronic debilitation such as cachexia, diarrhea, generalized lymphadenopathy, and weight loss usually are not found. Thirteen cases of American BL have been treated since 1980 at the Texas Childrens Hospital and form the basis of this review. Ten patients had obstructive abdominal symptoms including constipation and pain, and 3 had masses in the neck, maxilla, or tonsil. Systemic manifestations included ascites, jaundice, fever, and hepatosplenomegaly. Two patients ultimately developed central facial nerve paralysis.

Thyroid nodules in children.

Thyroid nodules are infrequently encountered in children. During the era of low-dose therapeutic irradiation, the incidence of malignancy in these lesions was 40% to 70%. Recent studies suggest that this incidence is declining, resulting in a concomitant relative increase in the proportion of benign nodular conditions. There is also a heightened awareness that secondary thyroid neoplasms may occur in children surviving primary malignant diseases. Records of 38 children treated surgically at Texas Childrens Hospital between 1972 and 1984 have been reviewed to determine the incidence of benign vs. malignant pathosis and to study the role of prior irradiation or chemotherapy in the pathogenesis of thyroid disease. Benign conditions were diagnosed in 27 children (71%), with diffuse hyperplasia (10 children, 26%) and follicular adenoma (8 children, 21%) occurring most frequently. Thyroid carcinoma was diagnosed in the remaining 11 children (29%). All of these patients were euthyroid at presentation, none had received multimodal therapy for a prior malignant condition, and only one had a history of head and neck irradiation in infancy for a treatment of a benign condition (a congenital hemangioma). The clinical presentation, diagnostic evaluation, and surgical management of these patients are reviewed and closely parallel those of patients in other recently published series. No conclusions can be drawn regarding the development of thyroid neoplasia following multimodal therapy for primary disease; however, this incidence must be very low.

Benign parotid diseases of childhood

A 25‐year retrospective study of 63 pediatric surgical cases of benign parotid disease was done. Inflammatory disorders accounted for 34 of the cases. The remaining 29 non‐inflammatory conditions included vasoformative, solid, and cystic lesions and were nearly always asymptomatic.