The uncinate process: a histological and morphological study.

The uncinate process (UP) has become a familiar anatomical landmark to otolaryngologists due to the increasing popularity of functional endoscopic sinus surgery (FESS) in recent years. This study examines the histological and morphological features of UPs removed from a group of patients undergoing FESS operations for chronic sinusitis. The structure of the UP by light microscopy (LM) is reported. A relatively high proportion of goblet cells and seromucous glands was noted. Scanning electron microscopy (SEM) identified four surface cell types on the UP. Furthermore, four categories of surface morphology were noted. The most common appearance was of predominantly ciliated cells. A nonciliated surface ultrastructure is associated with a longer history of sinonasal symptoms and a higher incidence of surgical intervention.

Histopathologic consequences of surgical approaches to the singular nerve.

Selective sectioning of the singular nerve has proven successful in the relief of incapacitating benign positional vertigo (BPV), presumably on the histopathologic basis of posterior ampullary cupulolithiasis. Although the surgical techniques of transmeatal and the recently introduced retrosigmoid IAC approach have been well described, little has been written about the singular nerve's anatomical relationships determined histologically for each surgical approach. The anatomical relationships of the singular nerve in both the transmeatal and retrosigmoid IAC approaches are discussed. Histologic evidence presented suggests that other mechanisms may also be ultimately responsible for improvement in the symptoms of BPV following transmeatal surgery. Moreover, the high incidence of injury to the endolymphatic duct during retrosigmoid surgery raises questions about the exact role of the endolymphatic duct and sac in inner ear homeostasis.

The early development of sino-nasal mucosa.

The development of human nasal mucosa was studied in 20 fetal heads between 8 and 24 weeks of gestation. Initially the nasal cavity is lined by a single layer of flattened cells, which produces two to three layers of undifferentiated spherical cells. Olfactory epithelium lines the cranial portion of the human fetal nasal cavity at 8 weeks of gestation. Pseudostratified ciliated cuboidal or columnar epithelium appears at 9 weeks of gestation in the nasal cavity and between 14 and 16 weeks of gestation in the primitive ethmoid sinuses and maxillary sinus infundibulum. Goblet cells and glandular acini appear between 12 and 14 weeks of gestation. Initially these goblet cells/glands are found predominantly in the anterior nasal cavity but are more evenly distributed at 24 weeks of gestation. The epithelial development of the nasal septum generally precedes that of the lateral nasal wall. This study documents nasal mucosal maturation and associated anatomic development in the human fetus.

The incidence and distribution of cupular deposits in the labyrinth.

Findings of large basophilic staining deposits on the cupula of the posterior semicircular canal ampulla have been used in part to explain the clinical phenomenon of benign positional vertigo (BPV). Although it is generally agreed that cupulolithiasis may involve other canal ampullae, the precise nature, distribution, and origin of these deposits remains unclear. In order to provide a better understanding of this finding, a series of 566 temporal bone specimens from the Ear Pathology Research Laboratory at the University of Toronto were reviewed. The results from this survey and speculations concerning the nature and formation of these deposits are discussed.

Histopathology of the temporal bone in osteogenesis imperfecta congenita: a report of 5 cases.

The histopathologic findings in 8 temporal bones from 5 patients with osteogenesis imperfecta congenita are reported. The otic capsule, bony walls of middle ear, and ossicles showed evidence of both deficient and abnormal ossification. Microfractures were found in the otic capsule and in the anterior process and handle of the malleus, in addition to their common location at the crura of the stapes. The cochlear and vestibular end-organs appeared normal. Pathologic changes compatible with otosclerosis were not seen. The possible implication of these changes on hearing and balance is discussed.

The embryonic development of the lateral nasal wall from 8 to 24 weeks.

This histological study of 20 fetal heads aged between 8 and 24 weeks of gestation demonstrates and describes the embryonic development of the lateral wall of the nose. The three turbinates (inferior, middle, and superior) arise as soft-tissue swellings (preturbinates) by 8 weeks' gestation. A cartilage capsule surrounds the nose at 8 weeks and by 9 weeks, medially directed flanges of cartilage have invaded all three preturbinates. The uncinate process arises from the medial surface of the lateral cartilaginous capsule and is first identifiable by 10 weeks. An "air space" progressively develops from 11 to 12 weeks lateral to the cartilaginous uncinate process and from this space, the embryonic channel to the maxillary sinus develops. The embryonic woven bone of the maxilla can be identified from 9 to 10 weeks and enlarges both absolutely and relatively to the nasal cavity, so that by 13 to 14 weeks, this expanding bone forms the lateral wall of the inferior meatus as the cartilaginous nasal capsule regresses.

Severe sensorineural hearing loss caused by lightning. A temporal bone case report.

To our knowledge, this article represents the second temporal bone case report in the literature of profound bilateral sensorineural deafness resulting from a lightning strike to the neck. Initial survival permitted antemortem audiologic testing, the results of which suggested severe cochlear abnormalities. Both temporal bones showed widespread inner-ear changes with absent organs of Corti, rupture and collapse of Reissner's membrane, strial degeneration, and a decreased spiral ganglion cell population. The occurrence of inner-ear trauma with an intact tympanic membrane and normal middle-ear structures suggests that a mechanism other than blast injury was responsible for the pathologic changes in this case.

Maxillary sinus hypoplasia, embryology, and radiology.

Maxillary sinus hypoplasia has been observed in up to 10% of radiological studies of the face or head. Although this may be a coincidental finding, it has been associated with chronic sinusitis and facial pain. Associated abnormalities of the lateral nasal wall, orbit, and ostiomeatal complex are common. The importance of this condition is, first, in the differential diagnosis of an "opaque" maxillary sinus and, second, as a potential hazard to the orbit of such patients, should they undergo functional endoscopic sinus surgery.

The influence of angiographically demonstrated coronary collaterals on the results of stress echocardiography.

Previous studies using thallium-201 scintigraphy have suggested that angiographic coronary collaterals can protect against the development of stress-induced perfusion abnormalities, but the effect of collaterals on stress echocardiography (SECHO) has not been determined. In this study, 21 consecutive patients referred for cardiac catheterization underwent SECHO and coronary angiography. Of the 21 study patients, there was a total of 16 significantly obstructed coronary arteries (> or = 70% stenosis) in 14 patients. SECHO revealed stress-induced wall motion abnormalities in the distribution of seven of nine obstructed coronary vessels without angiographic collaterals, but in only one of seven vessels with collaterals (p < 0.05). Six of eight obstructed vessels not associated with a stress-induced wall motion abnormality had collaterals, whereas only one of eight obstructed vessels associated with a stress-induced wall motion abnormality had collaterals. We conclude that (1) angiographically demonstrated coronary collaterals can protect against the development of stress-induced wall motion abnormalities despite the presence of a high-grade coronary artery obstruction, and (2) the lack of a stress-induced wall motion abnormality on SECHO in the perfusion territory of an obstructed vessel may suggest the presence of adequate collateral perfusion.

Surfactant in middle ear effusions.

Evidence from animal studies suggests that substances that lower surface tension are present in the middle ear cleft, where they may facilitate opening of the eustachian tube. The purpose of this study was to investigate whether or not surface-tension-lowering substances are present in middle ear effusions. Aspirates from children and adults with secretory otitis media--both serous otitis media and mucoid otitis media--were analyzed by means of two-dimensional thin-layer chromatography. Phospholipids, the major components of pulmonary surfactant, were present in appreciable quantities in all aspirates. Differences in total phosphate content and phospholipid composition were found when effusions from adults and children were compared.

Sudden hearing loss due to AIDS-related cryptococcal meningitis--a temporal bone study.

We have presented the clinical history and temporal bone findings in a patient who manifested sudden hearing loss, and who subsequently was found to have cryptococcal meningitis associated with AIDS. The histopathologic findings are similar to earlier reports in patients without AIDS. Because cryptococcal infection is so much more common in AIDS patients than in the general population, it must be considered a causative factor when presented with an AIDS patient with progressive or sudden hearing loss. This offers the patient a chance for timely and effective treatment.

Pharyngeal suspension suture with repose bone screw for obstructive sleep apnea.

OBJECTIVE: Multilevel surgery for obstructive sleep apnea syndrome (OSA) may improve success. This study's goal is to prospectively evaluate the feasibility and short-term subjective effectiveness of a new tongue-suspension technique. METHODS: A multicenter nonrandomized open enrollment trial used the Repose device to treat tongue obstruction in 39 snoring and OSA patients. Outcomes include 1- and 2-month subjective reports of general health, snoring, and sleep. RESULTS: Twenty-three patients completed 1 month and 19 completed 2 months of follow-up. In OSA patients, activity level, energy/fatigue, and sleepiness improved. Two-month outcomes were less (activity level, energy/fatigue, and sleepiness). Fewer changes were observed in snorers than in OSA patients. There were 6 complications (18%), including sialadenitis (4), gastrointestinal bleeding (1), and dehydration (1) after the procedure. CONCLUSION: A pharyngeal suspension suture changes subjective outcomes. Improvement is incomplete. The procedure is nonexcisional, but significant complications may occur. Further evaluation is required to demonstrate effectiveness.

Computer generated three-dimensional reconstruction of the bony labyrinth in Mondini's dysplasia.

The bony labyrinth obtained at necropsy in four cases was studied by a new computer-generated three-dimensional (3-D) system. One case was normal (control) and the other three were histopathologically confirmed cases of Mondini's dysplasia. In case 1, the cochlea had only 2 turns and the lateral semicircular canal did not make a circle but appeared as a spherical mass projecting from the utricle even though the posterior semicircular canal made a normal circle. In case 2, there were no turns in the cochlea even though the semicircular canals and the vestibule appeared normal. In case 3, the cochlea showed 1 to 1 and 1/2 turns and the semicircular canals were premature showing only bud-like projections. This 3-D imaging system, which utilizes the toggling method, provides a way of obtaining satisfactory images without markers, and the time required to obtain these 3-D images was reduced by using a video camera instead of a digitizer. One of the problems associated with the use of 3-D imaging is the long processing time. We resolved this by inputting the section images with a video camera and by picking up structures using density segmentation instead of tracing with a digitizer.

The function of migratory epidermis in the healing of tympanic membrane perforations in guinea-pig. A photographic study.

During observations on healing traumatic perforations in guinea-pig tympanic membranes, a specific appearance was seen on the surface of the epidermis as it closed the perforations. In this experiment, this pattern was identified on 15 tympanic membranes in 10 guinea pigs, and serial photography was used to record the healing process in 6 perforations over 5 days. This study shows that epidermis accumulates at the inferior margin of the perforation (the side from which it migrates) and then closes over the defect. Epidermal migration appears to be a key factor in this healing process.

An ink impregnation study of the migratory skin in the external auditory canal of the guinea-pig.

If the tympanic membrane or attic skin is wounded with a fine needle dipped in ink, ink particles are introduced into the epidermis and underlying tissue. These particles are subsequently taken up by cells in the epidermis and dermis. In this experiment the distribution of ink within the skin of ear canal was studied in nineteen guinea-pigs, one to ten days after wounding. Examination of the intact canal reveals that ink becomes distributed along a precise line from the wound to the point of desquamation. On sectioned tissue, the ink in this line is found to be mainly intracellular, initially in the epidermis, and subsequently in the upper dermis. When considered with other evidence, these results indicate that migration probably occurs in the deeper layers of the epidermis, and that it stops at the junction of the deep and superficial parts of the ear canal.

Bone resorption in chronic otitis media. The role of mast cells.

Twenty-two surgical specimens of eroded middle ear ossicles were removed from patients with chronic otitis media, with and without cholesteatoma. By using specific mast cell stains, increased numbers of mast cells were found in connective or granulation tissue adjacent to eroded surface of the bone. Mast cells possess the biological machinery necessary for enhancing bone resorption, and the population density of mast cells is increased in a variety of disorders that are associated with bone resorption. It is hypothesized that mast cells contribute to bone resorption in chronic otitis media, and the possible mechanisms by which mast cells exert their action are discussed.

Casts and crusts of the tympanic membrane.

Casts and crusts of the tympanic membrane were removed from patients with previous otitis media. Casts are formed of adherent keratinocytes in a matrix of dried exudate. Detachment from the drumhead leaves the underlying epidermis intact. Casts are defined as those crusts that have detached spontaneously from the surface of the drum. A mechanism based on epithelial proliferation induced by inflammation within the middle ear, with subsequent keratinocyte retention and thickening, is proposed.

Histamine levels in middle ear effusions.

The presence of histamine in 131 middle ear effusions was determined by the fluorometric assay technique. This potent mediator of inflammation was found in significant amounts in most of the samples, suggesting that it may play an important role in the pathogenesis of otitis media with effusion. It is postulated that mast cells located in the lamina propria of the tympanic mucoperiosteum are triggered to degranulate and release histamine by anaphylatoxin derived from activation of the complement system.

In situ localization of F-actin in the normal and injured guinea-pig tympanic membrane.

Although cell migration is an important function of the epithelial cells of the tympanic membrane (TM), little is known about the distribution of the F-actin cytoskeleton, a contractile protein important in cell motility. The purpose of this experiment was to study the in situ localization of F-actin in the epithelial cells of the TM. F-actin, localized using Rhodamine-phalloidin, was present as a thin cortical band at the margin of both the mucosal cells on the inner side of the drum, and the suprabasal cells of the epidermis. The basal cells showed diffuse circumferential F-actin staining sometimes appearing as short microfilaments. Following a full thickness injury, changes in the distribution of F-actin could be observed with in situ localization. While the diffuse F-actin staining of the basal cells was reduced, both long F-actin microfilament bundles extending parallel to the long axis of the cell and focal aggregates of F-actin were prominent. The suprabasal cells became elongated, and while the F-actin remained localized to the cell margin, faint central F-actin microfilaments were observed. The staining of the mucosal cells remained unchanged. This study showed that the guinea pig TM is a useful model to study the distribution of epithelial F-actin in situ under normal and repair conditions, and that the basal cell layer may be important in regulating migration in the epidermis.

Diagnostic imaging of fungal sinusitis: eleven new cases and literature review.

Fungal sinusitis should always be considered in the differential diagnosis of chronic or recurring sinusitis resistant to adequate medical treatment. A high index of suspicion is necessary for the diagnosis, and the clinical examination is rarely conclusive. The definitive diagnosis depends on the pathologist in most cases. We reviewed retrospectively the imaging findings, specifically computed tomography (CT) and magnetic resonance (MR), in a series of fungal sinusitis patients. Non-enhanced CT scan is more sensitive than conventional X-ray in detecting the classical focal areas of hyper-attenuation and calcification seen in soft-tissue masses of fungal sinusitis. MR findings of hypo-intense signals on T1-weighted sequences which progress to signal-void area on T2-weighted sequences, are characteristic features of fungal sinusitis; however, it is reserved for cases where intracranial invasion is suspected or CT findings are inconclusive.