Subfreezing versus room-temperature balloon dilation of benign tracheal stenosis: a pilot study in rabbits.

We conducted an experiment to compare collagen deposition in tracheal stenoses dilated with room-temperature balloons and stenoses dilated with balloons at a subfreezing temperature (-10°C). Six New Zealand white rabbits underwent endoscopic tracheal injury. Tracheal dilation was performed at 3 weeks postinjury with either a room-temperature balloon or a vascular cryoplasty balloon. Five surviving rabbits were sacrificed at either 2 weeks (n = 3) or 4 weeks (n = 2) postdilation (1 rabbit that was not able to tolerate dilation was euthanized during the procedure). A blinded pathologist graded histologic sections of the injured tracheas for collagen content. The tracheal collagen deposits in the 3 animals sacrificed at 2 weeks postdilation were all graded as moderate. However, at the 4-week postdilation examination, there was a marked difference in collagen deposition between the rabbit that underwent room-temperature dilation and the rabbit that underwent subfreezing dilation; while the former showed moderate collagen deposition, the deposition in the latter was only mild. In conclusion, this pilot study showed that tracheal dilation with balloon cryotherapy decreased collagen deposition in the injured airway of 1 animal. Larger studies are required to determine whether balloon cryotherapy improves the long-term patency of immature tracheal stenosis.

A prospective study to evaluate the efficacy of isopropyl alcohol irrigations to prevent cerumen impaction.

We conducted a prospective crossover study to assess the safety and efficacy of 70% isopropyl alcohol delivered from a squeezable bottle with a specially designed tip as a weekly irrigant to reduce cerumen accumulation. Twenty patients were divided into 2 groups of 10 (20 ears in each group). The patients in group 1 instilled 70% isopropyl alcohol once a week for 2 months; this was followed by 2 months of no ear cleaning. The patients in group 2 performed the opposite routine. At each visit (0, 2, and 4 mo), cerumen accumulation was graded on a scale of 0 to 4, indicating 0, 25, 50, 75, and 100% occlusion, respectively. After the accumulation was graded, a cerumenectomy was performed. At the initial evaluation, the mean occlusion scores were 3.1 for group 1 and 3.3 for group 2-not a statistically significant difference. After the first 2 months of the study, there was a significant difference in occlusion scores between groups 1 and 2 (0.75 and 1.55, respectively; p < 0.0002). At 4 months, after the crossover, the occlusion scores were 1.15 and 0.95, respectively, not a significant difference (p = 0.38). At study's end, there were also significant differences within each group between occlusion scores obtained during the treatment and nontreatment periods (group 1: p < 0.02; group 2: p < 0.01). All patients tolerated the alcohol rinse well, and there were no cases of external otitis or other complications. We conclude that weekly irrigation with 70% isopropyl alcohol is safe and reduces the accumulation of cerumen in the external auditory canal. Routine use should decrease the number of office visits for cerumen removal and hearing aid cleaning.

Mixed hearing loss in iatrogenic tympanic membrane perforations over the round window niche and the immediate effect of paper patch myringoplasty.

OBJECTIVES: Report the immediate audiologic effect of paper patch myringoplasty to repair iatrogenic tympanic membrane perforations directly over the round window. METHODS: Retrospective case-control study of 15 patients treated for inner ear disease with a MicroWick and dexamethasone for 1 month, resulting in 2-mm perforations over the round window. Paper patch myringoplasties were performed to repair the perforations. Audiograms were performed before and immediately after the paper patch myringoplasty. RESULTS: After paper patch placement, there was a significant improvement in air-bone gap at 250 (p < 0.001), 500 (p = 0.003), and 1000 Hz (p = 0.004) and a significant improvement in bone conduction (BC) threshold at 250 (p = 0.002), 500 (p < 0.001), 1000 (p = 0.002), 2000 (p = 0.003), and 3000 Hz (p = 0.02). CONCLUSIONS: Paper patch myringoplasty improves both air conduction and BC hearing from small perforations over the round window. The decrease in BC hearing is a result of middle ear mechanics and is not a true sensorineural hearing loss.

Early posttreatment audiometry underestimates hearing recovery after intratympanic steroid treatment of sudden sensorineural hearing loss.

Objective. To review our experience with intratympanic steroids (ITSs) for the treatment of idiopathic sudden sensorineural hearing loss (ISSNHL), emphasizing the ideal time to perform follow-up audiograms. Methods. Retrospective case review of patients diagnosed with ISSNHL treated with intratympanic methylprednisolone. Injections were repeated weekly with a total of 3 injections. Improvement was defined as an improved pure-tone average ≥20 dB or speech-discrimination score ≥20%. Results. Forty patients met the inclusion criteria with a recovery rate of 45% (18/40). A significantly increased response rate was found in patients having an audiogram >5 weeks after the first dose of ITS (9/13) over those tested ≤5 weeks after the first dose of ITS (9/27) (P = 0.03). Conclusions. Recovery from ISSNHL after ITS injections occurs more frequently >5 weeks after initiating ITS. This may be due to the natural history of sudden hearing loss or the prolonged effect of steroid in the inner ear.

Induction of tracheal stenosis in a rabbit model-endoscopic versus open technique.

OBJECTIVE: To evaluate and compare open versus endoscopic methods of inducing tracheal stenosis in the New Zealand white rabbit model. STUDY DESIGN: Prospective randomized control, pilot study. SUBJECTS AND METHODS: Fifteen New Zealand white rabbits were used in the study. Induction of tracheal stenosis was performed through an open incision in 6 rabbits, an endoscopic approach was utilized in 8 rabbits, and 1 rabbit served as the control. The open approach was performed by brushing the tracheal mucosa 10 times through an anterior tracheotomy with a nylon brush. The endoscopic method was achieved using a rigid bronchoscope and at a measured distance below the cricoid cartilage, passing the same nylon brush four times in each of four quadrants. Repeat endoscopies for evaluation of stenosis progression were performed at 2 and 3 weeks on all rabbits. RESULTS: In the open group, we observed no stenosis with one mortality as a result of gastroenteritis due to antibiotic use. In the endoscopic group, all animals achieved some degree of stenosis by 14 days, with a mean airway narrowing of 43%. The two deaths in the endoscopic group occurred in the immediate postoperative period secondary to laryngeal edema. The endoscopic procedure was 5 minutes in duration. CONCLUSION: The endoscopic technique is an effective method of achieving circumferential tracheal stenosis in the rabbit model. Advantages include simple instrumentation, an endoscopic approach, potential for decreased costs, and more reliable results.

Initial clinical experience with balloon dilation in revision frontal sinus surgery.

OBJECTIVES: The purpose of this study was to determine whether balloon dilation is effective in revision frontal sinus surgery. METHODS: We retrospectively reviewed all patients who had previously undergone endoscopic frontal sinus surgery and had persistent sinusitis. All patients then underwent balloon dilation of the frontal ostium. Outcome measurements included endoscopic patency of the frontal ostium, Lund-Mackay scores, culture-positive postoperative infections, and subjective persistence of symptoms. RESULTS: Twenty-four frontal ostia and recesses were dilated in 13 patients. The mean follow-up was 13 months (range, 7 to 19 months). During follow-up, 21 of 24 ostia (86%) remained patent and 3 required additional procedures. Postoperative computed tomography scans were performed an average of 12 months after dilation (range, 6 to 18 months) in 9 patients (17 sinuses). The average Lund-Mackay score was 1.35 before dilation and 0.87 at follow-up (p = 0.0076), with 41% of sinuses (7 of 17) displaying radiographic improvement. The average number of postoperative infections was 2.07 (range, 0 to 7). Frontal headaches persisted in 38% of patients (5 of 13) at follow-up. CONCLUSIONS: Balloon dilation of the frontal ostia has a posttreatment patency rate comparable to those of other endoscopic revision techniques. Although it may not fully address the frontal sinus disease of all patients, it is a less invasive technique that may be helpful for some patients.

Computed tomography and otosclerosis: a practical method to correlate the sites affected to hearing loss.

OBJECTIVES: We present a practical method for correlating computed tomography (CT) scans with hearing loss in otosclerosis. METHODS: We reviewed the CT scans of 18 patients (34 ears) with clinical otosclerosis who were seen between 2007 and 2008. The scans were reviewed by an otologist in a clinical office setting, followed by a blinded radiologist working at an imaging workstation. The 5 most commonly affected sites in otosclerosis were evaluated for evidence of otospongiosis and then correlated with the degree of air-bone gap and sensorineural hearing loss. RESULTS: Positive CT findings were noted in 70.5% of ears, with a 94% concordance between readings. The sites affected included the ante fenestram (21 ears), round window niche (12), cochlear promontory (4), cochlear apex (3), and posterior fenestram (2). The average air-bone gap increased with each additional site of involvement within an otic capsule (p = 0.004). The bone conduction threshold also increased, on average, with each additional affected site (p = 0.047). CONCLUSIONS: Most patients with clinical evidence of otosclerosis have evidence of otosclerosis on CT that is readily detected in the office setting. Ears with more affected sites have a significantly greater degree of air-bone gap and sensorineural hearing loss.

High dietary intake of sodium selenite induces oxidative DNA damage in rat liver.

One mechanism for the cancer-chemopreventive effects of high selenium (Se) intake is hypothesized to be antioxidant protection of DNA. In this work we examine DNA oxidation in whole animals as a function of dietary Se intake and carcinogen administration. Weanling male Sprague-Dawley rats were fed a basal, Torula yeast-based, Se-deficient diet supplemented with 0, 0.15, or 2.0 ppm Se as sodium selenite for 10 wk. They were then injected with 0, 0.1, or 10 mg /kg body weight of the pro-oxidant carcinogen N-nitrosodiethylamine. High levels of carcinogen and high levels of selenite intake each increased concentration of 8-hydroxy-2'-deoxyguanosine in liver DNA. Se-dependent glutathione peroxidase I gene expression and enzyme activity were dramatically reduced by dietary Se deficiency but were unaffected by carcinogen administration. There were no significant main or interactive effects of Se or carcinogen on activity or gene expression of the DNA repair enzyme 8-oxoguanine glycosylase I. These results do not support the hypothesis that high Se intake may be cancer-preventive by inhibiting oxidative DNA damage. Rather than inhibiting oxidative DNA damage, these findings suggest that high dietary intake of inorganic Se may promote in vivo DNA oxidation.