Investigating the learning curve in endoscopic compared to microscopic myringotomy and ventilation tube insertion.

OBJECTIVE: Rate of learning is often cited as a deterrent in the use of endoscopic ear surgery. This study investigated the learning curves of novice surgeons performing simulated ear surgery using either an endoscope or a microscope. METHODS: A prospective multi-site clinical research study was conducted. Seventy-two medical students were randomly allocated to the endoscope or microscope group, and performed 10 myringotomy and ventilation tube insertions. Trial times were used to produce learning curves. From these, slope (learning rate) and asymptote (optimal proficiency) were ascertained. RESULTS: There was no significant difference between the learning curves (p = 0.41). The learning rate value was 68.62 for the microscope group and 78.71 for the endoscope group. The optimal proficiency (seconds) was 32.83 for the microscope group and 27.87 for the endoscope group. CONCLUSION: The absence of a significant difference shows that the learning rates of each technique are statistically indistinguishable. This suggests that surgeons are not justified when citing 'steep learning curve' in arguments against the use of endoscopes in middle-ear surgery.

Age, smoking and nasal ciliary beat frequency.

The nasal ciliary beat frequency of 120 individuals in a British urban population was determined from nasal brushings. These individuals formed part of a previous study which looked at nasal and middle ear ciliary beat frequency in 60 patients with middle ear disease and compared it to nasal ciliary beat frequency in 60 matched controls. The present study intended to investigate any changes in nasal ciliary beat frequency with age. Comparison was also made between patients who were habitually exposed to tobacco smoke and non-exposed individuals. Nasal brushings were taken from the inferior turbinate using a cytology brush and the beat frequency was determined using a computerized photometric technique. In the population studied ages ranged from 2 to 69 years (mean 10.9 +/- 19.7 years). The mean beat frequency of 120 individuals was 11.5 +/- 2.5 Hz (SD), range 5.5-19.2 Hz. There was no particular trend observed with regards to beat frequency and advancing age. Nasal ciliary beat frequency in tobacco smoke-exposed patients (whether active or passive smokers) was significantly less than that in non-smoke exposed controls (P = 0.02, Student's t-test).

Increase in epithelial mast cell numbers in the nasal mucosa of patients with perennial allergic rhinitis.

The aim of the study was to compare the numbers and distribution of mast cells in the nasal mucosa of perennial allergic rhinitis (PAR) patients and controls, as demonstrated by different staining methods for light microscopy. Biopsies of inferior turbinate mucosa were taken from 10 patients with PAR and 10 patients undergoing septoplasty or septorhinoplasty (control group). Sections for light microscopy were stained with azure A. chloroacetate esterase and an ABC immunohistochemical technique using antibody to tryptase. Three times more mast cells were found in the epithelium of PAR patients compared to controls using the immunohistochemical technique (p = 0.0074). This method demonstrated considerably more mast cells than the other stains. The increase in epithelial mast cells is consistent with the migration of mast cells seen in seasonal allergic rhinitis, and this may be important in the phenomenon of nasal priming seen after repeated antigen exposure.

Mucociliary function in patients with nasal polyps.

Patients with nasal polyposis complain of nasal blockage and rhinorrhoea, which may be due to impaired mucociliary clearance. The saccharine clearance time and ciliary beat frequency of samples of ciliated epithelium from patients with nasal polyps was measured. We also studied the effect of fluid from the oedematous stroma of nasal polyps and of histamine and prostaglandin (PG) D2, E2 and F2 alpha on the cilia from normal individuals. Polyp fluid was found to increase ciliary beat frequency. Histamine and PGD2 had no effect, but PGE2 and PGF2 alpha both increased ciliary beat frequency and so may cause the ciliostimulatory effect of polyp fluid. The saccharine clearance time was prolonged in three of nine patients, but ciliary beat frequency was only slightly reduced in one of these. Thus, where mucociliary clearance is reduced, it is likely to be due to abnormalities of mucus rather than impaired ciliary activity.

Multiple rice body formation in chronic subacromial/subdeltoid bursitis: MR appearances.

Multiple rice body formation is an unusual complication of chronic bursitis. Clinically and macroscopically, it can resemble synovial osteochondromatosis. Radiographic and MR appearances, however, may allow an accurate pre-operative diagnosis. The imaging features of two middle-aged women with multiple subacromial/subdeltoid bursa rice bodies are described.

Papillary carcinoma arising in a thyroglossal duct cyst: a case report and literature review.

Papillary carcinoma arising in a thyroglossal duct cyst is a rare finding. Less than 100 cases have been reported in the English literature. In most cases the diagnosis is only established after excision of a clinically benign thyroglossal duct cyst. The aetiology of such tumours is unclear but de novo origin and spread from a primary thyroid gland tumour has been suggested. This has important implications for therapeutic approaches. A further case of thyroglossal duct carcinoma is presented and the management is discussed on the basis of the current rationale for treatment of thyroid cancer.

Nasal and middle ear ciliary beat frequency in chronic suppurative otitis media.

The middle ear mucociliary system has been shown to have an important function in the clearance of effusions. Little is known, however, about its role in chronic suppurative otitis media (CSOM). The ciliary beat frequencies of middle ear mucosal biopsies and nasal brushings of 27 patients with CSOM were analysed using a computerized photometric technique. The ciliary beat frequency in the middle ear mucosa was significantly less than that in nasal mucosa. Frequency in ears of smoking patients was significantly lower compared with non-smoking patients. Nasal brushings were taken from 27 otherwise healthy age and sex-matched non-smoking controls and the ciliary beat frequency was very similar to nasal samples from patients with CSOM. Ear controls were obtained from otosclerotic patients undergoing tympanotomy and the beat frequency was significantly higher than in the ear of patients with CSOM. It is concluded that middle ear ciliary function is significantly reduced in CSOM, particularly in patients who smoke.

The effect of temperature on nasal ciliary beat frequency.

Using a photometric method of measuring ciliary beat frequency, the effect of temperature on ciliary activity was investigated. A linear increase in ciliary beat frequency between 19 degrees and 32 degrees C was found. Between 32 degrees and 40 degrees a plateau was reached in which temperature did not significantly affect frequency and above 40 degrees C the frequency began to decline. It is concluded that nasal cilia are not critically dependent upon temperature in the range 32 degrees and 40 degrees C, the temperature range in which this tissue normally operates.

Smoking and middle ear ciliary beat frequency in otitis media with effusion.

The middle ear mucociliary system has been shown to play an important role in clearing middle ear effusions. There is conflicting epidemiological evidence, however, as to whether exposure to tobacco smoke plays a significant role in persistence of middle ear effusion in patients with otherwise normal mucociliary function. Samples of middle ear mucosa from 33 patients with persistent otitis media with effusion (OME) were taken at myringotomy, together with corresponding nasal brushings. The aim of this study was to observe the mean ear ciliary beat frequency (CBF) and to compare it with nasal ciliary activity. Nasal brushings were collected from 33 age and sex matched non-smoking controls with no history of nasal atopy or topical nasal treatment. Ear CBF in OME was significantly reduced in comparison to paired nasal samples (p < 0.001). Ear CBF in adult OME patients who smoked or in children who were passive smokers was significantly less than in patients who were not exposed to cigarette smoke (p < 0.01). This study indicates that impaired ciliary function due to tobacco smoke exposure is an aetiological factor in persistent OME.

Surface morphology of middle ear epithelium in chronic ear disease.

The ultrastructural details of normal middle ear mucosa have been reported in detail in the literature. This study was aimed at investigating the superficial structure of middle ear epithelium with the scanning electron microscope in patients with persistent otitis media with effusion (OME) and chronic suppurative otitis media (CSOM), especially in the light of the authors' recent findings regarding decreased ciliary beat frequency (CBF) in patients exposed to tobacco smoke. Mucosal biopsies were taken from the anterior mesotympanum in four patients with OME and another four patients with CSOM. There was no significant abnormality of cellular surface structure in patients with chronic middle ear disease. Furthermore, no significant difference was observed between smoke exposed and nonsmoke exposed patients. It is concluded that the effect of tobacco smoke on CBF is functional and not related to any anatomical abnormality observed by scanning electron microscopy (SEM).

Simultaneous bilateral pleomorphic adenomas of the parotid glands with unilateral tyrosine rich crystalloids.

A case of simultaneous, bilateral pleomorphic adenoma of the parotid glands following irradiation to the head and neck for childhood Hodgkin's disease is presented. The tumour on the side given the highest radiation exposure contained so-called tyrosine rich crystalloids (TRCs). Simultaneous salivary gland neoplasms are rare; TRCs are also an unusual finding. Simultaneous pleomorphic adenomas with TRCs confined to one tumour have never been described, and any association between TRCs and irradiation has never been commented on. The precise nature of the TRCs remains obscure. Their unilateral distribution in this case supports the hypothesis that local factors are more important in their formation than systemic factors. In conjunction with other published work, this provides circumstantial evidence that irradiation may predispose to TRC deposition.

Primary malignant melanoma of the pharynx.

A case of primary malignant melanoma of the pharynx is presented. Mucosal melanomas of the upper respiratory tract are rare. They tend to present late and therefore the prognosis is generally poor. The initial mainstay of treatment is adequate surgical resection. Prognostic factors are less well documented than in cutaneous melanoma.

P53 overexpression and Epstein-Barr virus infection in undifferentiated and squamous cell nasopharyngeal carcinomas.

We have analysed 22 nasopharyngeal carcinomas (NPCs) for expression of the small nuclear Epstein-Barr virus (EBV)-encoded RNAs (EBERs) and for immunohistologically detectable overexpression of p53. In situ hybridization demonstrated expression of the EBERs in 13 undifferentiated NPCs while nine squamous cell NPCs were EBER-negative. These results therefore confirm our previous DNA-DNA in situ hybridization studies and demonstrate that in the nasopharynx EBV is exclusively associated with undifferentiated but not with squamous cell carcinomas. p53 overexpression was demonstrated by immunohistology in 5 of 9 squamous cell NPCs and in 9 of 13 undifferentiated NPCs. Thus, there appears to be no correlation of p53 overexpression with EBV infection. These results are unexpected in the light of previous studies demonstrating that the p53 gene in primary undifferentiated NPC is consistently in the wild-type configuration. By contrast, analyses of squamous cell carcinomas of the head and neck have demonstrated that p53 overexpression in these cases is the result of p53 gene mutation. Whilst more detailed genetic analysis is required, our results suggest that mechanisms other than mutation of the p53 gene may be responsible for the stabilization of the protein in cases of undifferentiated NPC. It is tempting to speculate that an EBV-encoded protein may be involved.

Computerized measurement of ciliary beat frequency.

We describe how ciliary beat frequency (CBF) of human respiratory epithelium in vitro can be robustly and quickly measured. The proven photometric technique has been improved by using a microcomputer to calculate and display the results. The software, which runs on an IBM-compatible PC, was developed using Borland Turbo Pascal and employs a fast Fourier transform routine to derive the CBF. Results are displayed almost as soon as a cell is identified under the microscope, and are in accordance with previous work. The technique can now be used diagnostically and for a variety of drug trials on respiratory epithelium.

Ciliary ultrastructure in nasal brushings.

Normal ciliary ultrastructure is thought to be necessary for effective function. There has been little or no attempt to quantify ultrastructural abnormalities in nasal disease and assess their significance. In this study we measured nasal ciliary function and examined ciliary ultrastructure in nasal brushings from 35 patients with perennial nasal symptoms refractory to treatment. Ultrastructural defects included microtubular abnormalities, compound cilia and ciliary 'blebs'. The incidence of abnormal cilia was 16.7%, compared with 9% in controls, but there was only a poor correlation between ultrastructural defects and ciliary beat frequency. One patient had primary ciliary dyskinesia (PCD) with a typical clinical history and immotile cilia. However, only secondary ultrastructural abnormalities were seen. We have been unable to show that ciliary ultrastructural defects form the basis of impaired function. In patients with suspected PCD, nasal brushings should be taken for functional and ultrastructural studies; ideally, a further sample should be obtained for examination of possible primary ultrastructural abnormalities.

Factors affecting ciliary function in vitro: a preliminary study.

Nasal ciliary function forms an important defence mechanism within the upper respiratory tract which has largely been ignored in recent years. The effects of various drugs used extensively in the treatment of diseases of the nose have not been fully established. Furthermore, the physiological control of ciliary activity is unclear. The aim of this study was therefore to investigate the effects of drugs on ciliary beat frequency in vitro using a photometric technique. A dose-dependent response to alpha and beta receptor drugs was found, cocaine hydrochloride achieved ciliostasis even at 40-fold dilution, and potassium ions, except at the limits of tolerance for excitable tissue, did not affect ciliary function. In conclusion, we suggest that alpha and beta receptors may be present on ciliated epithelium and be involved in the control of ciliary function in vivo. Ion fluxes across the ciliary cell membrane may also be important in ciliary activity akin to nervous tissue.

Ciliary beat frequency of nasal and middle ear mucosa in children with otitis media with effusion.

Impaired mucociliary function of respiratory tract mucosa is associated with secretory otitis media in some well recognized syndromes. Ciliary activity per se may now be assessed directly by determination of ciliary beat frequency by a photoelectric technique. 49 children with otitis media with effusion undergoing surgical treatment were studied. Middle ear mucosa and nasal epithelial cells were obtained by biopsy and cytological brushings respectively at the time of surgery (myringotomy +/- grommet insertion under general anaesthesia). From these samples mean nasal ciliary beat frequency was 11.0 Hz and mean middle ear ciliary beat frequency was 11.2 Hz. A positive correlation exists between mean ciliary beat frequency of nasal and middle ear samples from individual patients. A comparison of mean ciliary beat frequency between children who were effusion positive and effusion negative at the time of surgery revealed no statistically significant difference. In addition, no difference existed between those children with recurrent otitis media with effusion and newly presenting cases. No prima facie evidence exists of impaired ciliary function in this population of children with otitis media with effusion.

An animal investigation into the effects of tympanostomy on middle ear mucociliary function and cilia.

The effect of tympanostomy on guinea-pig middle ear mucosa with particular reference to mucociliary function and cilia was investigated. 13 guinea-pigs were used; 5 acted as the control group with no surgical intervention whilst the other 8 had perforations made in one tympanic membrane. 6 weeks later an attempt was made to measure mucociliary function in all the ears, but this was unsuccessful. However, it would appear that fashioning a perforation in the tympanic membrane causes no histological changes in this animal model.

Nasal mucociliary function: comparison of saccharin clearance with ciliary beat frequency.

Mucociliary clearance as measured by saccharin clearance time is in part dependent on the physiological characteristics of mucus and is partly dependent on ciliary function. This study compared the relationship between saccharin clearance time and ciliary beat frequency in 44 patients attending a rhinology clinic. Whilst saccharin clearance time may be used as a screening test for ciliary function there was no clear linear relationship between mucociliary clearance and ciliary beat frequency.