Kenneth R. Whittemore

A normative study of tympanic membrane motion in humans using a laser Doppler vibrometer (LDV).

Laser Doppler vibrometry was used to measure the sound-induced tympanic membrane (TM) velocity, assessed near the umbo, in 56 normal hearing human subjects at nine sound frequencies. A second series of measurements was made in 47 subjects with sensorineural hearing loss (SNHL). Each set of measurements has features in common with previously published results. The measured velocity magnitude (normalized by the stimulus sound pressure) at any one frequency ranged among subjects by factors of 3-0.3 (+/-10 dB) from the mean and the phase angle of the normalized velocity ranged from +/-15 degrees around the mean at low frequencies to more than +/-200 degrees around the mean at 6 kHz. Measurements repeated after intervals of minutes to months were generally within 40% in magnitude (+/-3 dB) and 20 degrees in phase. Sources of variability included the effect of small differences in the location of the measurement on the TM and small static middle-ear pressures. No effects of stimulus level, ear sidedness (right or left), gender, age or the presence or absence of SNHL were found. These results provide a baseline normal response for studies of TM velocity with conductive hearing losses of different etiologies.

Nonsteroidal Anti-inflammatory Drugs and Postoperative Bleeding Following Adenotonsillectomy in Pediatric Patients

OBJECTIVE To assess the effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on bleeding for pediatric adenotonsillectomy in a retrospective study, based on the common practices at 2 different tertiary care facilities. DESIGN A retrospective study. SETTING Two different tertiary care facilities. PATIENTS Children up to 16 years of age, who underwent elective adenotonsillectomy or tonsillectomy, were included in the study. All indications for adenotonsillectomy, and all surgical techniques were included. Children with a bleeding tendency, and those with contraindications to the use of NSAIDs (eg, because of allergy), were excluded from the study. INTERVENTIONS Nonsteroidal anti-inflammatory drugs. MAIN OUTCOME MEASURE Postoperative bleeding in patients. RESULTS A total of 1160 patients were selected who met the criteria: 673 patients underwent an adenotonsillectomy or tonsillectomy and did not receive any preoperative and postoperative ibuprofen, and 487 patients underwent routine adenotonsillectomy or tonsillectomy and were given postoperative ibuprofen. We noted a 0.7% postoperative bleeding rate in patients who were not allowed to take ibuprofen perioperatively. There was a 1.0% postoperative bleeding rate in patients who were allowed to take ibuprofen perioperatively (P = .75). CONCLUSION Ibuprofen is not a contraindication to adenotonsillectomy or tonsillectomy and should be used in the control of postoperative pain if it is indicated in the patient.

Calbindin D-28k immunoreactivity in the medial nucleus of the trapezoid body declines with age in C57BL/6, but not CBA/CaJ, mice.

This study compared calbindin D-28k immunoreactivity in the medial nucleus of the trapezoid body (MNTB) in young (3-4 month old) and old (24-26 month old) CBA/CaJ mice, and young (3-4 month old), middle-aged (6.5-8.5 month old), and old (24-29 month old) C57BL/6 mice. C57BL/6 mice exhibit progressively more severe peripheral (sensorineural) hearing loss between 4 and 12 months of age, whereas CBA/CaJ mice show little change in peripheral sensitivity until very late in life. We obtained auditory brainstem response audiograms on all subject mice. Old CBA mice were selected for study whose audiograms matched those of young CBA and C57 controls. Middle-aged C57 mice showed elevated thresholds indicative of peripheral degeneration. Brain sections were reacted with anti-calbindin D-28k (CB). Staining patterns in Nissl and anti-CB material were characterized and cells were counted. We found no significant change in the number of CB+ cells or the total number of cells in the MNTB of old CBA mice compared to young controls. However, the mean number of CB+ cells decreased by 11% in middle-aged, and by 14.8% in old C57 mice. Since the decline in C57 mice was significant by 6.5-8.5 months of age, the decrease could be the consequence of a loss of input from the cochlear nucleus where cell numbers are known to decline by this age in this strain. The total number of neurons in MNTB assessed from Nissl material showed a more modest 7.1% decline with age in C57 mice, implying that the greater loss of CB immunoreactive cells with age cannot be completely attributed to a reduction in the total number of cells.

Enlarged vestibular aqueduct: Review of controversial aspects†‡

To review the controversial aspects of the enlarged vestibular aqueduct syndrome.

Acoustic mechanisms: Canal wall-up versus canal wall-down mastoidectomy ☆ ☆☆ ★ ★★

The contribution of the middle ear air spaces to sound transmission through the middle ear in canal wall-up and canal wall-down mastoidectomy was studied in human temporal bones by measurements of middle ear input impedance and sound pressure difference across the tympanic membrane for the frequency range 50 Hz to 5 kHz. These measurements indicate that, relative to canal wall-up procedures, canal wall-down mastoidectomy results in a 1 to 5 dB decrease in middle ear sound transmission below 1 kHz, a 0 to 10 dB increase between 1 and 3 kHz, and no change above 3 kHz. These results are consistent with those reported by Gyo et al. (Arch Otolaryngol Head Neck Surg 1986;112:1262-8), in which umbo displacement was used as a measure of sound transmission. A model analysis suggests that the reduction in sound transmission below 1 kHz can be explained by the smaller middle ear air space volume associated with the canal wall-down procedure. We conclude that as long as the middle ear air space is aerated and has a volume greater than 0.7 ml, canal wall-down mastoidectomy should generally cause less than 10 dB changes in middle ear sound transmission relative to the canal wall-up procedure. (Otolaryngol Head Neck Surg 1998;118:751-61.)

Imaging and review of a large pre-auricular pilomatrixoma in a child

A 10-year-old girl presented with a mildly tender mass in the right preauricular region. The mass became larger, and the overlying skin turned purple. There was no clinical response to a course of either cephalexin or clarithromycin. The remainder of the head and neck examination was normal including normal facial nerve function. Lyme titers and a computed tomographic (CT) scan with contrast of the facial region were obtained. The CT scan demonstrated the lesion to be superficial to the parotid gland. The lyme titer was elevated and doxycycline was begun. The mass appeared to reduce in size after doxycycline treatment, but then grew and turned erythematous. The lesion was surgically excised and was vascular with calcification and cheesy inclusions. The mass was quite close to the skin and the clinical diagnosis at the time of surgery was a pilomatrixoma, which was corroborated on pathological evaluation.

Clinical Uses of Cervical Vestibular-Evoked Myogenic Potential Testing in Pediatric Patients

AbstractTo demonstrate the feasibility and clinical significance of cervical vestibular-evoked myogenic potential (cVEMP) test in pediatric patients.Retrospective review study was conducted in a pediatric tertiary care facility. A total of 278 patients were identified with adequate data, including medical notes, results of cVEMP, and imaging studies.Among the total of 278 pediatric patients, only 3 children were not able to finish the cVEMP test successfully. In about 90% of the cases, the cVEMP test was requested to investigate a patient’s hearing loss and/or vestibular complaints. Over 90% of the cVEMP tests were ordered by specialists such as pediatric otolaryngologists or otologists. Obtained cVEMP results provided useful information in clinical diagnosis and management in all cases.It is feasible to conduct cVEMP testing in children, including infants, and cVEMP testing can provide valuable information in the diagnosis and management of hearing loss and vestibular impairment. This simple and noninvasive test should be embraced by pediatric professionals.

PHOTOSENSITIZATION AND TISSUE DISTRIBUTION STUDIES OF THE PICKET FENCE PORPHYRIN, 3,1-TPRO, A CANDIDATE FOR PHOTODYNAMIC THERAPY

Abstract— From a structurally distinct set of o‐substituted tetraphenylporphyrins, the picket fence porphyrin (PFP), 3,1‐meso‐tetrakis(o‐propionamidophenyl)porphyrin (3,1‐TPro) has been selected as a potential candidate for use in the photodynamic therapy (PDT) of cancer. In this report, the time‐dependent tissue distribution of 14C‐labeled 3,1‐TPro is described along with the results of various treatment regimens. The tissue distribution of radiolabeled 3,1‐TPro is comparable to that of other porphyrin photosensitizers with the advantage of being most effective at 4 h and being cleared rapidly from most tissues. The results of the various treatment regimen experiments, as well as other studies, indicate that the 3,1‐TPro mechanism of action is similar to that of other photosensitizers, but may include some minor differences. The conclusion is that 3,1‐TPro and other PFP offer a class of effective photosensitizers that may be exploited for their structural versatility, straightforward synthesis leading to a compound of high purity and known structure, and stability (both in terms of shelf‐life and in vivo metabolism) as potential candidates for PDT.

What is the role of tympanostomy tubes in the treatment of recurrent acute otitis media

BACKGROUND Approximately 90% of children will experience at least one bout of acute otitis media (AOM). An infection will most commonly occur within the first 2 years of life, with the highest incidence between 6 to 12 months of age. Recurrent AOM (rAOM) is generally defined as a child having a minimum of three bouts of AOM in a 6-month period or four bouts in 1 year. Treatment options for children with rAOM include episodic treatment with analgesics alone or antibiotics, prophylactic antibiotic therapy, or myringotomy with or without tympanostomy tube (TT) placement. Current guidelines by the American Academy of Pediatrics and the American Academy of Otolaryngology–Head and Neck Surgery are outlined in Table I.

Pediatric hearing assessment by auditory brainstem response in the operating room

OBJECTIVES To investigate the factors contributing to the discrepancies between auditory brainstem response (ABR) thresholds obtained in the operating room (OR) and hearing outcomes obtained in the follow-up period and to explore the benefits and limitations of performing ABR in the OR. METHODS A retrospective review study was conducted in a pediatric tertiary care facility. A total of 116 patients were identified with complete records, including OR-ABR results, medical examination and surgical procedure notes, and follow-up medical/audiological evaluation. Patients were divided into three groups: (1) 58 patients with middle ear effusion underwent myringotomy and tube placement, (2) 12 patients underwent myringotomy without tube placement, (3) 46 patients underwent ear examination only without effusion found. OR-ABR results were compared to audiological follow-up evaluations and analyzed for each group. RESULTS In patients with middle ear effusion and tube placement, the average threshold difference between OR-ABR and follow-up audiological evaluation was 9.7 dB (± 12.7), with highest discrepancy of 45 dB. On the other hand, in patients with dry ears and/or no tube placement, the average threshold difference was only 3.8 dB (± 8.6). Moreover, the discrepancy was more prominent in patients with mucoid effusion and larger at lower frequency, i.e., 1000 Hz. CONCLUSIONS The hearing thresholds estimated by ABR testing in the OR can be elevated and follow-up hearing evaluation after tube placement is needed. While ABR testing is valuable in the assessment of pediatric patients, especially for children who are difficult-to-test or have complicated medical conditions, caution should be taken when interpreting OR-ABR results.