Endoscopic ultrasonography in the diagnosis and staging of neoplasms of the head and neck.

BACKGROUND AND STUDY AIMS: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a minimally invasive and highly accurate method of detecting mediastinal lymph-node metastases in gastrointestinal and lung cancer. Little information is available regarding the use of EUS-FNA to stage tumors in the head and neck region. This study reports experience with EUS in the diagnosis and staging of these tumors and their mediastinal spread. PATIENTS AND METHODS: The records of patients who underwent EUS for diagnosis and/or staging of head and neck tumors were reviewed. Referral criteria were suspected invasion of the esophagus by a lower-neck mass on cervical computed tomography (CT) or magnetic resonance imaging (MRI), or mediastinal lymphadenopathy > 10 mm on a chest CT. RESULTS: Thirty-two patients (23 men, nine women; mean age 65 years, range 44 - 80) were referred and underwent 35 EUS examinations. In one patient, EUS was not possible due to a benign esophageal stricture. In 17 patients with suspected esophageal invasion on CT scans, EUS demonstrated invasion of the esophagus in four cases and of the pleura in one; 12 tumors showed no visible invasion of adjacent structures. The other 17 examinations were carried out for suspected mediastinal metastatic disease. In eight cases, EUS-FNA confirmed metastatic disease, whereas only benign changes were shown in the other nine cases. EUS-FNA also provided the first tissue diagnosis in two primary tumors and identified malignancy in one patient with no CT suspicion of positive mediastinal lymph nodes. EUS avoided the need for more invasive investigations in all patients with mediastinal lymphadenopathy, and it changed the management in 12 of the 17 patients (71 %) with suspected esophageal invasion and in eight of the 17 patients (47 %) with suspected mediastinal disease. CONCLUSIONS: EUS with FNA provides a viable approach to the diagnosis and staging of tumors in the head and neck region when there is a suggestion of esophageal invasion on CT or MRI, or enlarged mediastinal lymph nodes. EUS with FNA may avoid the need for mediastinoscopy or other more invasive techniques for staging of these neoplasms.

Potassium recycling pathways in the human cochlea.

OBJECTIVES/HYPOTHESIS: Potential pathways for recycling potassium (K+) used in the maintenance of inner ear electrochemical gradients have been elucidated in animal models. However, little is known about K+ transport in the human cochlea. This study was designed to characterize putative K+ recycling pathways in the human ear and to determine whether observations from animal models can be extrapolated to humans. STUDY DESIGN: A prospective laboratory study using an immunohistochemical approach to analyze the distribution of key ion transport mediators in the human cochlea. METHODS: Human temporal bones were fixed in situ within 1 to 6 hours of death and subsequently harvested at autopsy. Decalcification was accomplished with the aid of microwaving. Immunohistochemical staining was then performed to define the presence and cell type-specific distribution of Na,K-ATPase, sodium-potassium-chloride cotransporter (NKCC), and carbonic anhydrase (CA) in the inner ear. RESULTS: Staining patterns visualized in the human cochlea closely paralleled those seen in other species. Anti-Na,K-ATPase stained strongly the basolateral plasma membrane of strial marginal cells and nerve endings underlying hair cells. This antibody also localized Na,K-ATPase to type II, type IV, and type V fibrocytes in the spiral ligament and in limbal fibrocytes. NKCC was present in the basolateral membrane of strial marginal cells as well as in type II, type V, and limbal fibrocytes. Immunoreactive carbonic anhydrase was present in type I and type III fibrocytes and in epithelial cells lining Reissner's membrane and the spiral prominence. CONCLUSIONS: The distribution of several major ion transport proteins in the human cochlea is similar but not identical to that described in various rodent models. These results support the presence of a complex system for recycling and regulating K+ homeostasis in the human cochlea, similar to that described in other mammalian species.

Microwave decalcification of human temporal bones.

OBJECTIVES/HYPOTHESIS: Morphological and immunohistochemical studies of human temporal bones are challenging as a result of difficulties in obtaining reliably fixed specimens and the lengthy time required for decalcification, typically 4 to 7 months. A novel method of processing human temporal bones using a microwave oven to accelerate decalcification is described. This procedure provides a rapid means of decalcifying temporal bones with good preservation of tissue morphology and antigenicity. METHODS: Human temporal bone specimens obtained at autopsy (n = 12, from specimens aged 43-91 y) were fixed within 6.5 hours of death by transtympanic perilymphatic perfusion of the inner ear. Decalcification was carried out using ethylenediaminetetra-acetic acid (EDTA) in a microwave oven and required only 3 to 6 weeks. Specimens were then dehydrated, embedded in paraffin, sectioned, and mounted on slides for morphological and immunohistochemical evaluation. RESULTS: Microscopic examination revealed no obvious artifacts attributable to the microwave decalcification process. The quality of morphological preservation was largely dependent on the postmortem fixation interval and adequacy of perilymphatic perfusion. Immunohistochemical analysis demonstrated strong positive staining for the enzyme Na,K-ATPase, an integral membrane protein. CONCLUSIONS: This study demonstrates that microwave decalcification provides an efficient and reliable means of processing human temporal bones for histological and histochemical examination. Decalcification time is significantly reduced with no apparent adverse effects on structural preservation or antigenicity.

Canalicular reticulum in vestibular hair cells.

A membrane limited system referred to as canalicular reticulum (CR) has been demonstrated in the apical cytosol of the cochlea's inner and outer hair cells. Similarities between cochlear and vestibular hair cells prompted investigation of the presence of CR in hair cells of the gerbil vestibular labyrinth. A method of fixation with glutaraldehyde followed by an osmium-ferrocyanide mixture demonstrated abundant CR in the apex of both type I and type II hair cells. The CR was closely associated with numerous Golgi zones in the apex of the vestibular hair cells, indicating its genesis from Golgi cisternae. Also preserved in upper cytosol were discrete complexes of mitochondria with granular reticulum. These complexes offered a possible site for generating the membrane in Golgi zones and CR. Single and parallel cisternae of granular reticulum were observed in the basal half of the hair cells together with numerous synaptic-like vesicles. These cisternae with their terminal blebbing and accompanying canaliculi were interpreted as novel structures mediating synaptic vesicle genesis in vestibular hair cells in a manner comparable to that postulated for cochlear inner hair cells.

Adjunctive procedures in surgery of the aging face.

Acceptance of surgical treatment for rejuvenation of the aging face has increased over the past two decades. Face lift (or rhytidectomy) and blepharoplasty remain the basic procedures used in this surgery. Adjunctive procedures such as forehead lift, lipo-suction, chemical peel, chin augmentation, cheek augmentation, collagen injections, hair transplant and permanent eyeliner have been developed to enhance the results of surgery for rejuvenation of the aging face. All of this surgery can be, and usually is, accomplished using local anesthesia with intravenous sedation in an ambulatory surgical facility.

Demoplastic fibroma of the mandible. A case report.

Case of a 4-year-old boy with a desmoplastic fibroma of the mandible. Desmoplastic fibromas are benign fibrous neoplasms which are easily confused with other fibrous tumors. Although benign, they usually display aggressive local tissue extension and frequently recur when treated conservatively. At the present time, wide, local excision appears to be the treatment of choice.