Lateral Ear Research Articles

Does Endolymphatic Sac Decompression Surgery with Local Steroids Prevent Bilateral Development of Ménière's Disease?

Objectives: Elucidate whether endolymphatic sac decompression surgery (ESDS) has the potential to prevent unilateral Ménière’s disease (MD) from becoming bilateral. Methods: Prospective case-control study. Between 1996 and 2008, we performed a glycerol test (G-test) and electrocochleography (ECoG) on 237 patients with intractable MD at a tertiary referral center. We performed ESDS on 179 patients (144 without endolymphatic hydrops and 35 with silent endolymphatic hydrops in the contralateral ear). The other 58 patients (40 without endolymphatic hydrops and 18 with silent endolymphatic hydrops in the contralateral ear) were given available medical treatments. All underwent regular follow-up for at least 5 years. Results: Altogether, 22.4% (53/237) of patients with clinically diagnosed unilateral intractable MD had silent endolymphatic hydrops in the contralateral ear using G-test and ECoG. In the nonsurgical group, 6 of 40 patients with unilateral MD without endolymphatic hydops in the contralateral ear developed bilateral disease, whereas in the surgical group, 12 of 144 patients did so ( P > .05). In the nonsurgical group, 9 of 18 patients with unilateral MD and silent endolymphatic hydrops developed the disease in the contralateral ear, whereas in the surgical group, 6 of 35 patients developed bilateral disease ( P < .05). Conclusions: The present findings suggest that ESDS may decrease the incidence of developing MD in silent endolymphatic hydronic contra lateral ears diagnosed with G-test and ECoG within the first 5 postoperative years.

Correction of asian short nose with lower lateral cartilage repositioning and ear cartilage grafting.

Asians with short nose lack the cartilage needed to extend the length of the nose. A rhinoplasty technique using lower lateral cartilage (LLC) repositioning and ear cartilage grafting allows for sufficient nasal lengthening and nasal tip mobility in the correction of short nose in Asians. Short nose was classified into 3 subtypes: type I, II, or III. During LLC repositioning, the LLC was separated from surrounding retaining structures, except at the footplate. The LLC was approximated medially and advanced with a Medpor strut. A silicone dorsal implant was inserted to suit the newly projected nasal tip. An ear cartilage onlay graft or ear cartilage extension graft was applied to further project and enhance the nasal tip and columella. Of the 854 primary rhinoplasty procedures performed on Asian patients between January 2008 and December 2011, 295 were performed on patients with short nose. LLC repositioning and ear cartilage onlay grafting were performed on 228 patients. LLC repositioning and ear cartilage extension grafting with or without ear cartilage onlay grafting were performed on 67 patients. Short nasal tip, alar retraction, and columellar retraction were corrected. Wound dehiscence with marginal necrosis occurred in 7 patients. One patient developed nasal infection. LLC repositioning and ear cartilage grafting aid in the correction of short nose in Asians. With LLC repositioning and ear cartilage grafting, the nasal tip can be positioned in accordance with the patient's anatomic limits. The entire nasal tip and columella can be lengthened, while the tip maintains its mobility.

Malignant Fibrous Histiocytoma/Undifferentiated High-Grade Pleomorphic Sarcoma of the Maxillary Sinus

Malignant fibrous histiocytoma (MFH) also known as undifferentiated high-grade pleomorphic sarcoma (UHPS) is a soft tissue sarcoma, composed of undifferentiated mesenchymal tumors possessed fibrohistiocytic morphology without definite true histiocytic differentiation. Head and neck localization is very rare, showing an incidence ranging from 4 % to 10 % in different series of investigations. The most frequent involved sites in UHPS are the neck and parotid, followed by the scalp, face, anterior skull base and orbit. Upper aerodigestive tract, lateral skull base and ear are rare locations. The incidence of the lymphatic metastases is also rare. The aim of this article is to report a case of UHPS in the maxillary sinus with palatal, orbital and ethmoidal involvement, with lymphatic metastasis and its surgical treatment. In addition, we review the literature of similar cases of the past 12 years.

Alterations in the Contra lateral Ear in Chronic Otitis Media.

Chronic otitis media (COM), a persistent and durable inflammation and infection of the middle ear, is a common disorder. Alterations in the contralateral ear in sufferers have been observed in recent years. Because only a few studies have been reported in this area, we performed this study in order to assess alterations in the contralateral ear of patients with COM. Cross-sectional and descriptive methods were used in 100 patients with COM who were selected for surgical treatment and admitted to hospital. An information form was completed for all patients including demographic data, medical history of otoscopy and paraclinical examinations such as pure tone audiometry (PTA), tympanometry, Schuller radiography, and high resolution computed tomography (HRCT). All data were processed using SPSS (version 18) software and descriptive statistical tests. According to otoscopy, PTA, tympanometry and graphical analysis, 60% of patients experienced disorders of the contralateral ear. Otoscopy analysis showed 54% of patients had a disorder of the contralateral ear, with the most common disorder being perforation of the ear drum. PTA showed a 48% incidence of contralateral ear problems (85% conductive hearing impairment; 12.5% sensorineural hearing impairment; 1.2% mixed). A total of 73.2% of patients with conductive hearing loss had a problem across all frequencies, while half of the patients with sensorineural hearing impairment had problems at frequencies greater than 1000 Hz. According to tympanometry, 38% of patients had problem in the contralateral ear. HRCT and Schuller graphical analyses indicated 31.5% and 36% occurrence of contralateral ear disorders, respectively. More than 50% of patients with COM in one ear have a chance of also presenting with the disease in the other ear. Outcomes of this study and previous studies have shown that COM should not be perceived as a disease limited to one ear, because in most cases the progress of the disease can affect both ears.

Evaluation of two doses of ceftiofur crystalline free acid sterile suspension for treatment of metritis in lactating dairy cows

The objectives of this study were to evaluate efficacy of a 2-dose regimen of ceftiofur crystalline free acid sterile suspension (CCFA-SS) for treatment of acute metritis in lactating dairy cows under field conditions and to provide additional safety and injection site tolerance data for injections at the base of the ear. Cows at 15 dairies with rectal temperature ≥39.5°C and fetid uterine discharge ≤10 d postcalving were randomly assigned by blocks of 2, based on order of entry and without regard to parity, to treatment with saline (1.5mL/45.5kg of body weight, n=509) or CCFA-SS (6.6mg of ceftiofur equivalents/kg of body weight, n=514). Treatments were administered by subcutaneous injection in the posterior aspect of the ear where it attaches to the head; the first dose was administered on study d 0 and the second dose was administered in the contra lateral ear on study d 3. Rectal temperatures were recorded on study d 1 to 4 and 5 or 6 and cows were clinically evaluated daily from study d 1 to 13. Cows that exhibited increased adverse clinical signs of poor health or complications associated with metritis were categorized as a treatment failure and administered escape therapy. Each cow received a veterinary physical examination on study d 5 or 6 to determine if she should be removed from the study and on study d 14 to determine clinical cure or failure to cure. Clinical cure was defined as rectal temperature <39.5°C and non-fetid and purulent or mucopurulent discharge on study d 14 and no escape therapy administered. The injection procedure was scored after each injection (study d 0 and 3) and injection sites and ear carriage were scored on study d 5 or 6, 14, and 57±3. Of the 1,023 cows enrolled, 7 were completely censored due to protocol deviations and 34 were removed for protocol deviations or medical conditions not related to metritis. Clinical cure rate was higher for CCFA-SS than for saline (74.3 vs. 55.3%) and rectal temperatures for each of study d 1 to 5 or 6 were lower for CCFA-SS than saline. Injection procedure indices showed that CCFA-SS could be practically and safely administered using commercial dairy facilities. Although injection site scores were higher for CCFA-SS than saline at study d 5 or 6 and 14, ≥98.6% of ears were normal on d 57±3. Thus, a 2-dose treatment with CCFA-SS given 72h apart increased metritis clinical cure rate and was well tolerated in dairy cows.

Application of fascia of the temporal muscle and cartilage of the auricular tragus in myringoplasty in children

Perforation of the tympanic membrane in children may be the cause of recurrent middle ear infection and loss of hearing. The aim of this study was to analyze the application of different reconstructive materials in surgical technique myringoplasty. We performed 88 myringoplasties due to auricular tragus perforation in 76 children (aged 4 to 16 years, mean 11.9 years) from July 2001 to July 2009. Age, gender, size and the site of perforation, status of the contra lateral ear, underlying cause of the perforations, surgical technique, preoperative and postoperative hearing levels and postoperative complications were recorded and analyzed. In performing myringoplasty we used fascia of the temporal muscle and cartilage of the auricular tragus. In 43 (48%) patients we used fascia of the temporal muscle and in 45 (52%) cartilage of the auricular tragus. Graft success was defined as an intact eardrum at 12 months postoperatively and improvement in the perception of air-bone gap of 10 dB, which we recorded in 73 (83%) cases. Re-perforations were recorded in 12 (13%) patients, of whom in 8 (18.6%) cases we used the temporal fascia and in 4 (9.3%) cases a tragal cartilage. Retraction of the tympanic membrane was recorded in 3 (4%) cases with the temporal fascia. Myringoplasty is a reasonably successful method with good functional results in pediatric patients. Risk factors of surgical failure are young age, the size of auricular tragus perforation and pathological conditions of the contra lateral ear. The tragal cartilage gives better results in cases with bilateral perforations because the possibility of retractions and re-perforations is lower. Relatively small number of patients is probably the reason that, exept for young age, differences between the two groups did not reach the level of statistical significance.

BAER Testing in a Dog with Bilateral External Ear Canal Atresia

A 3 yr old male castrated Labrador retriever presented for evaluation and treatment of bilateral atresia of the external ear canals. The owners reported that the dog could hear only loud and high-pitched noises. Computed tomography of the head revealed intact vertical and horizontal ear canals filled with debris and a debris-filled right tympanic bulla. Air- and bone-conducted brainstem auditory evoked response (BAER) testing revealed an elevated response threshold to air-conducted stimuli and greater amplitude waveforms evoked by bone-conducted stimuli. The ear canals were surgically corrected via lateral ear canal resection. BAER testing postoperatively revealed a decrease in the air-conducted BAER threshold. This case is an example of the use of bone-conducted BAER testing to aid in the diagnosis of conductive deafness, and in determining prognosis for normal hearing after surgical treatment of external ear canal atresia.

Grassy tillers1 promotes apical dominance in maize and responds to shade signals in the grasses

The shape of a plant is largely determined by regulation of lateral branching. Branching architecture can vary widely in response to both genotype and environment, suggesting regulation by a complex interaction of autonomous genetic factors and external signals. Tillers, branches initiated at the base of grass plants, are suppressed in response to shade conditions. This suppression of tiller and lateral branch growth is an important trait selected by early agriculturalists during maize domestication and crop improvement. To understand how plants integrate external environmental cues with endogenous signals to control their architecture, we have begun a functional characterization of the maize mutant grassy tillers1 (gt1). We isolated the gt1 gene using positional cloning and found that it encodes a class I homeodomain leucine zipper gene that promotes lateral bud dormancy and suppresses elongation of lateral ear branches. The gt1 expression is induced by shading and is dependent on the activity of teosinte branched1 (tb1), a major domestication locus controlling tillering and lateral branching. Interestingly, like tb1, gt1 maps to a quantitative trait locus that regulates tillering and lateral branching in maize and shows evidence of selection during maize domestication. Branching and shade avoidance are both of critical agronomic importance, but little is known about how these processes are integrated. Our results indicate that gt1 mediates the reduced branching associated with the shade avoidance response in the grasses. Furthermore, selection at the gt1 locus suggests that it was involved in improving plant architecture during the domestication of maize.

Mastectomy Approach With Y-Shaped Incision

To evaluate the access to axilla, postoperative complications, and cosmetic results of the modified radical mastectomy with a Y-shaped approach especially designed for women with obesity. One hundred seventeen consecutive women with obesity with infiltrating breast cancer were studied. All of them were not eligible for breast-conserving therapy and underwent modified radical mastectomy. Operation was performed using a surgical technique designed to improve the axillary clearance and to eliminate the lateral dog ear deformity. Two oblique incisions were added to the traditional transverse Stewart incision at the lateral part forming the Y-shaped approach. After lateral flap retraction, the axillary dissection was done. Before closing the wound, the triangular flap was advanced medially, whereas superior and inferior areas of redundant skin overlying the latissimus dorsi muscle were excised. No intraoperative complications were observed. In each case, the axillary dissection (with level 3 node clearance when needed) was performed with ease. The wound was healed by primary adhesion, giving an excellent cosmetic result without lateral dog ear deformity. Skin flap necrosis was found in 2 elderly patients. Wound hematoma and surgical site infection developed in 1 patient each. Necrosis of the apex of axillary triangle occurred in one woman with diabetes. These rare complications were managed successfully in all the cases. The Y-shaped approach for modified radical mastectomy is a simple and safe technique. It facilitates the wide access to axilla and improves cosmesis in women with obesity by eliminating lateral dog ear deformity.

Urotensin‐II Induces Ear Flushing in Rats

While investigating the effects of systemic urotensin II (U-II), a potent vasoactive peptide acting at the UT receptor, we observed ear pinna flushing after systemic administration to conscious rats. In the present study, U-II-induced ear flushing was quantified in terms of ear pinna temperature change and potential mechanisms were explored. U-II-induced ear flushing was quantified by measuring lateral ear pinna temperature changes and compared to that of calcitonin gene-related peptide (CGRP), a known cutaneous vasodilator. Further, the effects of a variety of pharmacological agents on U-II-induced ear flushing were explored. Subcutaneous injection of U-II (9 microg kg(-1))produced localized ear pinna flushing with an onset of approximately 15 min, a duration of approximately 30 min and a maximal temperature change of 9 degrees C. In contrast, CGRP caused cutaneous flushing within multiple cutaneous beds including the ear pinna with a shorter onset and greater duration than U-II. A potent UT receptor antagonist, urantide, blocked U-II-induced ear flushing but did not affect CGRP-induced ear flushing. Pretreatment with indomethacin or L-Nomega-nitroarginine methylester (L-NAME) abolished U-II-induced ear flushing. Mecamylamine or propranolol did not affect this response to U-II. Direct intracerebroventricular injection studies suggested that the ear flushing response to U-II was not mediated directly by the CNS. Our results suggest that U-II-induced ear flushing and temperature increase is mediated by peripheral activation of the UT receptor and involves prostaglandin- and nitric oxide-mediated vasodilation of small capillary beds in the rat ear pinna.

The physoclistous swim bladder of chaetodontid butterflyfishes: Implications for acoustic function

Butterflyfishes (genus Chaetodon) have a swim bladder lateral line connection (laterophysic connection, LC), hypothesized to convert sound-induced oscillations of the swim bladder into fluid flow in the lateral line system and/or ear. Evaluation of LC function is dependent upon an understanding of swim bladder acoustics, which is a function of swim bladder anatomy. We used several anatomical methods (including CT) to describe swim bladder and tunica externa and tunica interna morphology (including gas gland/rete mirabile complex and the oval, responsible for gas secretion and resorption) in Chaetodon and Forcipiger. Swim bladder and tunica externa morphology differ between Chaetodon spp. with different LCs morphologies. A perforated transverse diaphragm divides the gas volume into two compartments. The gas gland/rete mirabile complex is in the ventral midline of the anterior compartment; it varies in morphology and is largest in species with a direct LC. The oval, defined by an extensive capillary network, occupies the entire tunica interna of the posterior compartment, so that diaphragm position determines oval size. These data raise questions about swim bladder structure-function relationships with respect to the reception and transduction of acoustic stimuli in coral reef fishes. [Work supported by NSF Grant IBN-0132607 to J.F.W.]

Twenty-four hours or 10 days? A prospective randomised controlled trial in children comparing head bandages following pinnaplasty

The perceived benefits of bandaging for 10 days following pinnaplasty have been questioned by previous studies. The problems arising from these dressings are many [Powell BWEM. The value of head dressings in the postoperative management of the prominent ear. Br J Plast Surg 1989;42:692-4. Bartley J. How long should ears be bandaged after otoplasty? J Laryngol Otol 1998;112:531-2. Wong MC, Sylaidis P. Head dressings for pinnaplasty: a tradition not supported by evidence. Br J Plast Surg 2001;54:81-2], including their slippage [Powell BWEM. The value of head dressings in the postoperative management of the prominent ear. Br J Plast Surg 1989;42:692-4. Bradbury ET, Hewison J, Timmons MJ. Psychological and social outcome of prominent ear correction in children. Br J Plast Surg 1992;45:97-100. Jeffery SLA. Complications following correction of prominent ears: an audit review of 122 cases. Br J Plast Surg 1999;52:588-90]. Eighty children were recruited into a prospective randomised controlled trial comparing the use of a head bandage for only 24 h with a standard practise of a 10-day head bandage. A preoperative measurement of the lateral ear projection (LEP) was made. The outcome measures recorded during the two planned postoperative visits at 10 days (visit 1) and 2 months (visit 2) were: patient satisfaction score, LEP, complications and any unscheduled hospital visits associated with the surgery. There was no significant difference in LEP and patient satisfaction between the two groups at both the scheduled postoperative visits. Differences between the groups in the number of unscheduled visits (p=0.21) did not reach statistical significance. The findings indicate that it is safe and effective to use head bandage for only 24 h following surgical correction of prominent ears. This study shows no benefit from the application of a formal head bandage for any longer than 1 day.

Muscle‐derived stem cells used to treat skin defects prevent wound contraction and expedite reepithelialization

Stem cells derived from adult tissues may serve as cell therapy to enhance the healing process in skin wounds. This study was designed to evaluate the use of autologous muscle-derived stem cells in an experimental skin wound model in terms of their efficiency at promoting tissue repair/regeneration. Muscle-derived cells obtained from the dorsal muscle of New Zealand rabbits were cultured in vitro for 2 weeks. The cell population was identified using the satellite markers CD34, m-cadherin and Myf5, and the proliferative capacity of the adult stem cells was determined. The population was then fluorescently labeled with PKH26 and seeded onto a circular 2 cm diameter defect created on the dorsal side of the ear of the rabbit from which the cells had been harvested. Similar defects on the contra lateral ears were left untreated to form the control group. Fourteen days later, specimens were taken for light, transmission, and scanning electron microscopy, as well as for immunolabeling with antibodies against vimentin, alpha-actin, desmin, myosin, fibronectin, and cytokeratin 14. Areas of wound contraction and reepithelialization were determined by image analysis. Wound contraction was significantly greater in the control than the treatment group (p<0.05); control specimens also showed more myosin expression. Reepithelialized areas were significantly greater in the treatment group (p<0.05). Control wounds showed nonepithelialized areas and inflammatory granulation tissue. Reepithelialization occurred as epidermal tongues of fusiform cells. Our findings indicate that the use of autologous stem cells on skin wounds expedites and improves the organism's natural healing process.

Vestibular Schwannoma in the Only Hearing Ear: Cochlear Implant or Auditory Brainstem Implant?

To explore the dilemma faced by neurotologists confronted with the patient who develops a vestibular schwannoma in the only hearing ear, the other having been deaf from birth, and to consider the choice between auditory rehabilitation using a cochlear implant (CI) on the congenitally deaf side and an auditory brainstem implant (ABI) on the tumor side. A record review of two patients born deaf in one ear and who developed a vestibular schwannoma in the contra lateral ear, who then received a CI in the congenitally deaf ear. Tertiary referral center with special experience in vestibular schwannoma surgery, neurofibromatosis type 2 management, and cochlear implantation. Neither patient was a good CI user. At 1 year postimplant, they both scored 0% on abbreviated words and 0% and 7%, respectively, on Bench Kowal Bamford sentences. They scored 54% and 57%, respectively, on City University of New York sentences with lip-reading, and both had fair access to environmental sound scoring at 45% each. The results from cochlear implantation in the congenitally deaf ear in these patients were poor and suggest that stimulus deprivation in the early stages of the maturation of the auditory pathways is important even for a unilateral hearing loss. Unfortunately, the factors that predict a good ABI result are not known. In these circumstances, the authors advocate the insertion of an ABI at the time of tumor removal, retaining the option of CI in the congenitally deaf ear in the event of a poor outcome with the ABI.

Relative Processing Demands Influence Cerebral Laterality for Verbal-Motor Integration in Persons with Down Syndrome

The study of cerebral specialization in the Down syndrome (DS) population has revealed an anomalous pattern of organization. In particular, dichotic-listening studies have suggested a left-ear/right hemisphere dominance for speech perception, whereas motor control research has revealed a left hemisphere dominance for executive-motor control. In the present investigation, we employed a recent adaptation of the dichotic listening procedure to examine interhemispheric integration during the performance of a lateralized verbal-motor task. Specifically, using the selective dichotic-listening procedure, participants were required to complete a rapid left or right hand pointing movement to one of two pictorial icons corresponding to the word presented to their precued ear. We observed that persons with DS (N = 17) and age-matched controls (N = 35) exhibited a right-ear advantage (REA) for our dichotic-aiming task. While these results appear to contradict previous dichotic listening studies, we propose that the manifestation of a lateral ear advantage in the DS population may have more to do with the response requirements of the task than with the characteristics or complexity of the stimulus material.

Sensorineural hearing loss in patients with chronic otitis media

Objectives: Chronic otitis media is currently associated with an increase in air conduction thresholds. However, a few groups reported a decrease in sensorineural function in these patients. This study evaluates the occurrence of sensorineural hearing loss in patients with chronic otitis media. Methods: The records of patients with unilateral chronic otitis media were reviewed. Eighty-four patients met the inclusion criteria that were normal otoscopy and normal hearing in the contra lateral ear. Bone conduction threshold averages were calculated over 500 Hz, 1000 Hz, 2000 Hz, 3000 Hz and 4000 Hz frequencies. We compared the bone conductions threshold averages between the normal ear and the ear with chronic otitis media. Thresholds were examined separately for each frequency. Results: The bone conduction threshold averages in the normal side were smaller than those of the chronic otitis media ear. The threshold shift was statistically significant in each frequency ( P < 0.001 t Student test) but in 500 Hz ( P = 0.16). There were no differences between the groups when we analyzed the role of age or in the role of the cholesteatoma presence in the sensorineural hearing loss. Conclusions: This study shows that chronic otitis media is associated with decrease in cochlear function. Neither the presence of cholesteatoma in the middle ear nor the patients’ age showed any influence in the sensorineural hearing loss.

Surgical management of 43 cases of chronic otitis externa in the dog

Over a seven-year period, chronic otitis externa was surgically managed in 43 dogs at the University Veterinary Hospital of University College Dublin. Lateral ear canal resection (LECR) was undertaken in nine of the 43 dogs: results were unsatisfactory, with a failure of the surgery in five of eight dogs and one dog lost to follow-up. Once end-stage otitis externa, with or without otitis media, is diagnosed, total ear canal ablation and lateral bulla osteotomy (TECA/LBO) is the best treatment option. In this series, 37 of 43 dogs underwent TECA/LBO and of the 29 dogs for which follow-up results were obtained 27 (93%) had an excellent or improved outcome to surgery. Complications following all procedures were most common in cases with a concurrent dermatopathy; therefore, definitive diagnosis and medical treatment for skin and ear disease is essential.

Cerebral specialization and verbal-motor integration in adults with and without Down syndrome

Persons with Down syndrome (DS) tend to exhibit an atypical left ear–right hemisphere advantage (LEA) for the perception of speech sounds. In the present study, a recent adaptation of the dichotic listening procedure was employed to examine interhemispheric integration during the performance of a lateralized verbal-motor task. Although adults with DS ( n=13) demonstrated a right ear–left hemisphere advantage in the dichotic-motor task similar to their peers with ( n=14) and without undifferentiated developmental disabilities ( n=14), they showed an LEA in a free recall dichotic listening task. Based on a comparison of the laterality indices obtained from both dichotic listening procedures, it appears that the manifestation of lateral ear advantages in persons DS may dependent on the response requirements of the task.

The laterophysic connection: A novel specialization thought to enhance sound pressure sensitivity in butterflyfishes (Chaetodontidae, Chaetodon)

Morphological specializations that enhance sound reception have been described among fishes, but sources of behaviorally-significant sound stimuli and sound transduction mechanisms are known for very few bony fishes. Butterflyfishes in the genus Chaetodon have a unique sensory specialization, the laterophysic connection (LC), defined anterior swim bladder extensions (horns) in association with medial openings in the lateral line canals of the cranial supracleithral bones. The LC is hypothesized to enhance sensitivity of both the lateral line and ear to sound pressure. Variation in LC morphology among species is defined by variation in soft tissues and is thought to be functionally significant. Preliminary field studies demonstrate that C. multicinctus produces sounds during agonistic interactions, thus providing a source of potentially relevant sound stimuli. Presence of an inflated swim bladder in close proximity to well-developed supracleithral openings in pelagic tholichthys stage individuals (15 mm SL) and horn development at the end of the tholichthys stage (25–29 mm SL) in C. ocellatus suggests that sound may also play an important role in the early life history of Chaetodon. [Work supported by the NSF IBN-9603896 to J.F.W.]

Lateral ear canal resection and segmental pinnal excision in a horse to remove a sarcoid

Lateral ear canal resection and segmental pinnal excision in a horse to remove a sarcoid