Blindness due to electrocoagulation following functional endoscopic sinus surgery

A case is presented with irreversible blindness in one eye and restriction of the infratemporal visual field in the other eye, due to electrocoagulation performed for delayed bleeding after functional endoscopic sinus surgery (FESS). Although blindness due to rhinosurgery is a well-known, but rare complication, a review of the recent literature did not reveal a similar incident. The use of electrocoagulation especially under conditions of poor visualization, that may be the case in post-operative bleeding following (endoscopic) sinus surgery, is strongly discouraged.

MRI of acoustic schwannoma: a retrospective study of 89 tumours

Magnetic resonance imaging (MRI) is now considered the diagnostic study of choice for evaluation of patients with suspected acoustic schwannoma. This retrospective study of 118 MR examinations presents an analysis of the MR findings of 89 acoustic tumours in 86 patients. The method of examination included precontrast and gadolinium(Gd)-enhanced MRI in 72 and plain MRI in 14 patients. The common MR-appearances of acoustic schwannomas were: on T1-weighted images (WI) isointense (36%) or slightly hypointense (64%) relative to the brainstem; intense and homogeneous contrast enhancement in 62%; the shape of the tumour was round or oval in 71%; the tumour was centred at/or located in the internal auditory canal (IAC) in 80%. The small acoustic schwannomas were mostly round or oval in shape and showed homogeneous signal intensity (SI) both before and after Gd. The larger acoustic tumours were more heterogeneous in morphology and SI. The significance of these and other signs, early diagnosis and differential diagnosis are discussed.

Psychoacoustical tuning curves. Normative data for clinical use

This normative study presents a clinically applicable method with which to obtain Psychoacoustical Tuning Curves: data are obtained with clinical audiometers, and measurements are performed on normal-hearing non-trained volunteers. A simultaneous masking method with test frequency of 4,000 Hz was used, withmasking being incremented in 5 dB or 1 dB steps. One group of subjects was tested three times with 5 dB incrementing steps to evaluate the method's reproducibility. A second group of subjects was measured twice with 1 dB incrementing steps, to compare the reproducibility of the 1-dB step measurements, and the difference between the 1-dB step and 5-dB step measurements. All the data were evaluated as normative values. The method presented proves to have a good reproducibility. Although testing with 1-dB incrementing steps provides more accurate measurements and curves with steeper slopes, the 5-dB incrementing step method is more practicable. Interest variability evaluation indicates that differences between two measurements performed on the same person exceeding 120 Hz (2 SD) bandwidth can be interpreted as significant.

Aminoglycoside-induced ototoxicity

One of the major side effects of aminoglycoside antibiotics (AG) is ototoxicity. The authors review the literature revealing many controversies on every aspect of this side-effect. Although epidemiological studies have to face the problem of reliable evaluation techniques, the incidence of cochleo- and vestibulotoxic side-effects has been estimated at 7.5% for each. Netilmicin appears to be less ototoxic. No definite risk factors can be proposed, although age, length of therapy, bacteremia, fever, liver and renal dysfunction are probably very important parameters. Most pathological changes at the cochlear level follow a clear spatial sequence, showing unspecific, degenerative lesions, involving every structure of the cochlea. This makes it impossible to draw etiopathological conclusions. Recent pharmacokinetic studies have rejected the 'accumulation theory' of AGs in perilymph, while also in endolymph no accumulation can be found. Only a few data are available on inner ear tissue levels. Among the different pharmacodynamic hypotheses on the action of AGs, binding of the drug to acidic glycosaminoglycans in the stria vascularis, and interference by the drug with phosphoinositide metabolism in the hair cells seem to be of major importance.

Effect of topical levocabastine on allergic and non-allergic perennial rhinitis. A double-blind study, levocabastine vs. placebo, followed by an open, prospective, single-blind study on beclomethasone

Forty-four patients, with symptoms of nasal obstruction, sneezing, itching and/or rhinorrhea, were entered into a placebo-controlled, double-blind study to evaluate the clinical efficacy of a topical antihistamine drug, levocabastine, applied 4 times a day for 14 days. At the end of the treatment the placebo patients were treated with levocabastine and the levocabastine patients were treated with beclomethasone dipropionate in a single-blind design for another 14 days. This study showed that levocabastine is significantly more active than placebo with reference to nasal discharge and sneezing. Placebo application improved the symptom score. Levocabastine could not be proved to be more effective against nasal obstruction than placebo in the double-blind trial. In the single-blind set-up, levocabastine resulted in an additional improvement in the score for obstruction, after the placebo period. Although the allergic group tended to respond better, no statistically significant difference could be detected between allergic and non-allergic patients. After treatment with levocabastine, beclomethasone dipropionate administration could not improve the results for nasal discharge and sneezing. For nasal congestion, beclomethasone dipropionate proved to be superior to levocabastine.

The use of fluoroquinolones in chronic otitis suppurativa

The present review covers fluoroquinolone usage in chronic otitis suppurativa (COS) in case of chronic otitis media, cholesteatoma, radical mastoid cavity infection and chronic or relapsing otitis externa. A total of six publications were included in the final evaluation. Enoxacin was effective in 35%; ciprofloxacin (five publications) was used in 82 patients with 67% effectivity in otitis externa and otitis media and 61% effectivity in radical mastoid cavity infection. No serious adverse reactions were reported. The promising efficacy of otitis media and otitis externa and safety profile needs further confirmation in double blind prospective clinical studies, that will provide a firm basis for changing the current treatment schedules of COS.

A search for the most suitable imminent components and probe tone frequency in tympanometry

The relative occurrence of bell-shaped and various types of W-shaped susceptance-conductance and admittance-phase tympanograms at a probe-tone frequency of 660 Hz was determined from registrations on normal ears. The diagnostic value of the susceptance-conductance versus the admittance-phase representation of tympanograms was studied on pathological middle-ear systems. Using probe-tone frequencies from 510 Hz up to 910 Hz, tympanograms for all four imminent components were recorded on 10 pathological ears and the diagnostic value compared. From the combination of these studies we conclude that the admittance-phase approach at a probe tone frequency between 500 and 700 Hz is a good choice.

Incudo-stapedial joint pathology: a tympanometric approach

Two-component tympanometry with a high probe-tone frequency enables a better distinction to be made between mobile but normal middle-ear systems and middle-ear systems suffering from necrosis, luxation, or disruption. Susceptance and conductance tympanograms obtained from 14 patients with confirmed pathological middle-ear lesions and 8 postmortem temporal bones, experimentally manipulated either surgically or with a 1 N HCl solution, were compared to tympanograms obtained from 80 normal subjects of an earlier study. With a 660-Hz probe tone, normal middle ears generate bell-shaped or normal sharp W-shaped patterns, whereas the pathologies of the middle ear give rise to irregular multi-extrema tympanograms. The differences between the two types of multi-extrema curves are discussed in detail. The use of phase-angle tympanometry is recommended to enable a quick and accurate distinction between normal and abnormal types of multi-extrema tympanograms. This study also points out clearly that 220-Hz tympanograms do not allow clear differentiation between pathological and normal middle ears.