Effect of perilymphatic fistulas on evoked otoacoustic emissions in the guinea pig.

Round window perilymphatic fistulas were surgically created in 20 guinea pigs. Distortion product otoacoustic emissions (DPOAEs) at 2fl - f2 were recorded prior to and immediately following laceration of the round window. The stimuli were equal level sinusoids (f1 < f2) with f2 ranging from 2 to 10 kHz, a fixed f2:f1 ratio of 1.25, and stimulus levels (L2 = L1) ranging from 20 to 80 dB SPL. After an 18-day survival period, emission measurements were repeated, and fluorescein was infused into the cerebrospinal fluid to verify patency or closure of the fistula. Nine animals demonstrated patent fistulas, whereas 11 had closed fistulas. There was a statistically significant reduction in DPOAE amplitude after an acute fistula across all stimulus levels (p < .001). At 18 days the DPOAE amplitudes in animals with healed fistulas could not be differentiated from controls, whereas DPOAE amplitudes in animals with patent fistulas were statistically different from controls (p < .05). The results suggest that evoked otoacoustic emissions may be useful in detecting perilymphatic fistulas.

Correlation between stroboscopy and electromyography in laryngeal paralysis.

Twenty patients with vocal fold motion impairment were reviewed to correlate the findings of electromyography (EMG) and stroboscopy. The causes of motion impairment were idiopathic, previous surgery with recurrent laryngeal nerve injury, neck and skull base trauma, and neoplasm. The EMG studies were analyzed to assess the status of innervation of the immobile vocal fold. The presence or absence of the mucosal wave prior to therapeutic intervention was determined with stroboscopic examination. Eight of 10 patients with EMG evidence of reinnervation or partial denervation were found to have mucosal waves, and 3 of 10 patients with EMG evidence of denervation were found to have mucosal waves. Six patients developed mucosal waves after surgical medialization, despite evidence of denervation by EMG criteria. These findings support the premise that tension and subglottic pressure, rather than status of innervation, determine the presence of the mucosal wave.

Vertically fused tracheal cartilage. An underrecognized anomaly.

Anterior vertical fusion of the tracheal cartilages with normal pars membranacea is a rarely described tracheal anomaly. We report four cases of this anomaly, three associated with craniosynostosis syndromes and one with Goldenhar's syndrome. The anomaly was documented at postmortem examination in one case, both endoscopically and at tracheotomy in two cases, and endoscopically in one case. Documentation from gross postmortem photographs, photomicrographs, and intraoperative endoscopic photographs is presented so that the anatomical aspects of this anomaly can be thoroughly understood and recognized. All four newborn patients developed recurrent lower respiratory tract infections, reactive airway disease, and chronically retained secretions attributable to this anomaly. Neither tracheal stenosis nor stridor was encountered. In the three surviving patients, the infections grew less frequent and less severe in later childhood. These observations suggest that this tracheobronchial anomaly may be associated with a variety of craniofacial syndromes and may alter airflow dynamics in a way that predisposes to retained secretions and chronic pulmonary disease.

Pentoxifylline in the nonoperative management of intermittent claudication.

To assess the clinical effectiveness of pentoxifylline (Trental) in the treatment of intermittent claudication and ischemic rest pain, 129 patients were retrospectively interviewed with respect to compliance and improvement of symptoms. Risk factors for the development of atherosclerosis were tabulated, as was the severity of symptomatic lower extremity peripheral vascular insufficiency. The duration of pentoxifylline treatment was 35.8 +/- 45.0 weeks (mean +/- 1 S.D.). Forty-eight percent of the patients discontinued pentoxifylline on their own, most commonly because of side effects (13%) or perceived lack of improvement (23%). Of those patients taking pentoxifylline for eight weeks or more (n = 110), 64% noted some improvement, with 31% reporting increased claudication distance and 52% reduced claudication pain. Pentoxifylline provided pain relief in 52% of patients with ischemic rest pain (n = 27). Neither diabetes, hypertension, concomitant antiplatelet therapy, the severity of claudication, nor pretreatment ankle-brachial Doppler pressures were related to treatment outcome. Increased daily walking exercise during treatment was associated with successful outcome (p = 0.04). Clinical response to pentoxifylline was inversely related to the number of cigarettes smoked daily in those with 1 block claudication (n = 71, p = 0.05). Pentoxifylline was not very effective in increasing reported claudication distance. This review suggests that pentoxifylline may be of value for patients with ischemic rest pain when arterial reconstruction is not possible. Whether pentoxifylline is useful adjunctive therapy for intermittent claudication requires further scrutiny.