Pediatric Epistaxis-Effectiveness of Conservative Management.

OBJECTIVES: Epistaxis is an emergency medical condition that sometimes requires admission to the emergency department. Pediatric epistaxis differs from epistaxis in the older population in terms of etiology, severity, and management. Our objective was to identify the distinctive features of pediatric epistaxis and determine the appropriate management. METHODS: This was a retrospective study of 231 medical records of children (<18 years old) with epistaxis of a total of 1171 cases in the general population who presented to our medical center's emergency department between 2013 and 2018. RESULTS: Among 231 admissions, 10 children (4.3%) presented more than once. Male patients accounted for the majority of cases (64.5%), and the average age was 9.4 years. Two children were treated with aspirin because of cardiac valve disease. Anterior bleeding was detected in 101 cases (43.7%), whereas posterior origin was observed in 8 cases (3.5%). In 122 cases (52.8%), there was no active bleeding observed. Nose injury was the cause of epistaxis in 24 cases (10.4%), and 16 admissions (6.9%) followed nasal surgical interventions. Nineteen children (8%) had abnormal coagulation tests, and 7 patients (3%) received blood transfusions. Chemical cauterization was performed in 89 cases (39.3%), and anterior packing was needed in only 9 cases (3.9%). Nine children required hospitalization (3.9%), and 2 needed surgical intervention to control bleeding. Compared with the adult population, there were significantly fewer cases of active bleeding, recurrent epistaxis, anterior packing, or need for hospitalization in the pediatric population. CONCLUSIONS: Epistaxis is significantly less severe in the pediatric population, with only a few cases requiring major intervention. Endoscopic examination of the entire nasal cavity and routine coagulation tests are not mandatory unless there is a history of recurrent epistaxis, known coagulopathy, antiplatelet/anticoagulation therapy, or a suspicion of juvenile idiopathic angiofibroma. We suggest using absorbable packs, which offer advantages over cauterization or nonabsorbable packs.

Posisep Versus PureRegen Gel for Post ESS Nasal Packing - A Randomized Blinded Prospective Study.

OBJECTIVE: Endoscopic sinus surgery (ESS) is the procedure of choice for chronic rhinosinusitis (CRS). Adhesions are the most common postoperative complications, causing recurrent disease and revision surgery. Postoperative care is thus essential for the healing of the operated cavity. A wide variety of packing materials are used to prevent bleeding and adhesions postoperatively. Two main absorbable packing materials are used: Foam-based packs (e.g., Posisep and Nasopore) and gel-based packs (PureRegen Gel - PRG). The current study is a randomized, blinded, prospective analysis of cavity healing using Posisep and PRG in ESS, aiming to compare the pros and cons of the two. METHODS: Patients with bilateral symmetric CRS were recruited for the study. At the end of surgery, one side was randomly packed with Posisep, whereas the other was packed with PRG. The postoperative cavity cleaning was video recorded and a blinded physician evaluated the mucosal healing. RESULTS: The side packed with Posisep had significantly less middle turbinate (MT) lateralization and adhesions yet dissolved significantly slower than the PRG, causing more mucosal edema. Severe MT scarring requiring recurrent medialization and adhesiolysis was exclusively observed in the PRG group. All differences were observed in the early postoperative period (up to 12 weeks after surgery). By that time, only the MT position was significantly different between groups, despite recurrent adhesiolysis and medialization. CONCLUSION: The authors recommend using Posisep for MT support only when it is unstable or lateralized. Packing the surgical cavity in other cases with PRG is more beneficial. LEVEL OF EVIDENCE: 2 Laryngoscope, 133:1834-1838, 2023.

The management of acute supraglottitis patients at the intensive care unit.

INTRODUCTION: Acute supraglottitis is a potentially life-threatening condition that often necessitates intensive care unit (ICU) admission for airway monitoring. The objective of this study was to identify clinical criteria that predict a benign course for patients with acute supraglottitis. METHODS: A prospective observational study was performed. Adult patients hospitalized in the ICU between 2007 and 2019 diagnosed with acute supraglottitis were included. All patients were treated with antibiotics and corticosteroids. Fiber optic laryngoscopy (FOL) was performed every 12 h, with each exam defined as "improving", "no change" or "deteriorating" based on the presence of airway edema. Need for airway intervention was correlated to changes in the FOL exam. RESULTS: Of 146 patients included, 14 (10%) required intubation, ten on admission, and four during the first 6 h of ICU admission. FOL follow-up was performed on 528 occasions-427 (81%) exams showed improvement, 16 (3%) deterioration, and 85 (16%) with no change. On no occasions was improvement in FOL followed by deterioration. The median ICU length of stay was 3 (IQR 2-3.5) vs. 1 (IQR 1.0-1.25) day for patients who did or did not require intubation (p < 0.001), respectively. CONCLUSION: Improvement in FOL exam accurately predicted the absence of need for intubation and might represent a criterion for early ICU discharge.

Vascular Anomaly in the Fallopian Canal Encountered Unexpectedly During Cochlear Implantation.

A 68-year-old male with progressive sensorineural hearing loss underwent left cochlear implant surgery. While developing the posterior tympanotomy and identifying the facial nerve mastoid segment, gentle stimulation by the nerve stimulator resulted in unexpected profuse venous bleeding. After achieving hemostasis with Surgicel and Spongostan, the posterior tympanotomy was extended exposing a large aberrant vein running parallel to the tympanic and mastoid segments of the facial nerve in the fallopian canal. Good exposure and careful palpation of the vein assisted in ruling out facial nerve hemangioma. An intraoperative decision to proceed with implantation, taking into account limited benefit from future magnetic resonance imaging, was taken. The patient had a temporary 3-month post-operative facial nerve weakness, probably from pressure applied during hemostasis. Auditory cochlear implant function was excellent. A larger than normal diameter of the tympanic and mastoid segments of the facial nerve was seen in re-reviews of the preoperative computed tomography. We believe drawing the readers' attention to this anomaly, which to the best of our knowledge has not been previously described, can assist in the choice of preoperative imaging and increase awareness of deviation from the norm of facial nerve diameter. In addition, knowledge of possible venous anomalies may aid surgeons in such intraoperative decisions.

Revision cochlear implantation using a double array device in the post-meningitis ossified cochlea.

PURPOSE: To describe the surgical technique and outcome in a series of patients who underwent revision cochlear implantation using a double array or split electrode device. All patients developed ossified cochleae due to meningitis and were functioning poorly with the previous implant. METHODS: Four patients between the ages of 4-15 years underwent revision with five double-array cochlear implant devices. One patient underwent bilateral revision surgery. All patients had previous meningitis with CT and MRI imaging studies that demonstrated completely ossified cochleae. The time interval range between the disease and the initial cochlear implantation and was 4 months to 3 years. The patient's data were retrospectively analyzed with emphasis on the surgical technique, the number of electrodes inserted, and the number of active electrodes at follow-up. In addition, pre and post-revision surgery function was compared. RESULTS: The revision surgery was carried out 2-11 years after the initial surgery. Two tunnels, basal and apical, were drilled in the ossified cochlea. In each of the tunnels, 5 to 11 electrodes were inserted. While the number of active electrodes before revision was 0-5, after revision with the double array, it was increased to 8-12, resulting in improved auditory and speech function. CONCLUSION: Revision cochlear implantation with a double array implant using the two tunnel technique can increase the number of active electrodes. This leads to a better outcome in post-meningitis children with completely ossified cochleae and a poor functioning previous device.

Supraglottoplasty for severe laryngomalacia. Can we predict success?

OBJECTIVES: Laryngomalacia is the dynamic collapse of supraglottic structures during inspiration, leading to a variable degree of airway obstruction. Clinical symptoms appear in the first months of life and are usually mild and resolve by the age of 12-18 months. In severe cases, surgical intervention may be considered. The goal of the study was to review the clinical outcome of pediatric patients who underwent supraglottoplasty for laryngomalacia. MATERIAL AND METHODS: Clinical and demographic data were retrieved from medical records of children diagnosed with laryngomalacia by laryngo-bronchoscopy between 2013 and 2019. Indications, outcome and long-term follow-up were collected from children undergoing surgery. RESULTS: During the study period, 115 children were diagnosed with laryngomalacia. The median age at diagnosis was 3 months. Synchronous airway lesions were diagnosed in 20% of patients. Ten (8.7%) children underwent surgical treatment because of significant respiratory symptoms and/or failure to thrive. Three of them had comorbidities. All otherwise healthy children had significant respiratory and nutritional improvement after surgery while those with comorbidities had less successful outcomes. CONCLUSION: We conclude that in severe cases of laryngomalacia, supraglottoplasty has an important role to play in management. In children with comorbidities, the surgical results may be less successful. Therefore, we recommend that the decision to operate should be individualized, ensuring full disclosure to the family regarding the probable benefit along with the limitations of surgery.

Starplasty tracheostomy: case series and literature review.

OBJECTIVES: The starplasty tracheostomy (SPT) technique has been suggested to reduce the short-term complications of tracheostomy, including accidental decannulation and pneumothorax. The aim of the present study was to conduct a review of key parameters prior to and following treatment of neonates and children with the SPT technique, including indications, complications, perioperative department stay, and overall length of stay in one University-Affiliated Medical Center. METHODS: A retrospective chart review of all children under the age of 18 underwent SPT in a single center between February 2006 and January 2012. RESULTS: Among the 39 patients reviewed, the median age at the time of surgery was 14.5 months, ranging from 3 days to 8.8 years. The most common indication for SPT was respiratory insufficiency resulting from central nervous system disorders (15, 38.4%) followed by neuromuscular disorders (14, 35.9%). Ten (25.6%) operations were performed on neonatal intensive care unit (NICU) patients and 29 (74.4%) on pediatric intensive care unit (PICU) patients. The median postoperative hospital stay was 19.5 days (range of 3-207 days); however, the median postoperative stay in the PICU was 13.5 days. There were no decannulations or any other short-term complications after SPT, and no SPT-related deaths occurred. CONCLUSIONS: In our series, pediatric SPT was not associated with any major complications. Therefore, we conclude that SPT should be considered as a safe and advantageous alternative for traditional tracheotomy, especially in patients with low probability of future decannulation, and, therefore, at low risk of a persistent tracheocutaneous fistula.

Bipolar tonsillotomy: A novel and effective tonsillotomy technique.

OBJECTIVE: To present, for the first time, tonsil size reduction using reusable bipolar forceps electrocautery (RBFE), as a treatment for pediatric OSAS and to assess the safety and efficacy of the procedure. METHODS: A prospective interventional design study was performed. Thirty children aged 2-15 years with OSAS (AHI>5) diagnosed by means of polysomnography were included. All children were treated with adenoidectomy and RBFE tonsillotomy without dissection. Re-polysomnography was performed after 1 year. The size of the tonsils was blindly assessed by two ENT specialists and the parents were asked to fill out 'Pediatric Sleep Questionnaires' (PSQ), before surgery, and one month and one year after surgery. RESULTS: There were no complications during or after surgery. There were no events involving postoperative bleeding or dehydration. The surgery mean time, including adenoidectomy, was 20.6min. The AHI was 10.9 before surgery and decreased to 1.8 after surgery (p<0.001), minimum saturation (SaO2 min) increased from 86.1% to 93.2% (p<0.001). The size of the tonsils decreased from a mean of +3.3 before surgery to +1.3 and +1.4 one month and one year after surgery, respectively. The mean of the PSQ scores went down from 23.6 to 5.5 and to 6.2 one month and one year after surgery, respectively. CONCLUSION: We demonstrated that simple cauterization of the tonsils using a RBFE device with an adenoidectomy is a safe and effective treatment to decrease tonsil size in OSAS. In addition, the method is inexpensive, rapid and does not cause bleeding, which may be particularly interesting in the presence of coagulation problems.

The Immune Interplay between Thyroid Papillary Carcinoma and Hepatic Fibrosis.

BACKGROUND: A high prevalence of thyroid papillary cancer was reported in hepatitis-C-virus (HCV) positive patients. However, the mechanistic role of hepatic-fibrosis in thyroid malignancy progressions is still unclear. AIM: We aimed to study the immune-modulatory interactions between thyroid papillary carcinoma and hepatic-fibrosis. METHODS: Hepatic-fibrosis was induced in nude-nu-male mice by intra-peritoneal administration of carbon-tetrachloride. To induce thyroid-tumor, a thyroid papillary carcinoma cell line (NPA) was injected subcutaneously in the backs. Fibrotic profile was estimated by α-smooth-muscle-actin (αSMA) expression in liver tissue extracts using western-blots and RT-PCR. Intra-hepatic NK cells were isolated and stained for NK activity (CD107a) by flow cytometry. Liver histopathology (H&E staining), thyroid tumor mass and serum alanine aminotransferase (ALT), serum vascular endothelial growth factor (VEGF) and free-T4 levels were also assessed. RESULTS: Ex-vivo: NPA cells were co-cultured with intra-hepatic NK cells isolated from fibrotic mice with/without the tumor were analyzed for CFSE-proliferations. Both tumor groups (with/without hepatic-fibrosis) excreted higher serum free T4 levels. Hepatic-fibrosis increased tumor weight and size and serum free-T4 levels. In addition, tumor induction increased liver injury (both hepatic-fibrosis, necro-inflammation and serum ALT levels). In addition, tumor-bearing animals with hepatic-fibrosis had increased NK activity. NPA tumor-bearing animals increased fibrosis in spite of increased NK activity; probably due to a direct effect through increased serum free-T4 excretions. Serum VEGF levels were significantly increased in the fibrotic- bearing tumor groups compared to the non-fibrotic groups. In-vitro, NK cells from fibrotic tumor-bearing animals reduced proliferation of NPA cells. This decrease is attributed to increase NK cells activity in the fibrotic animals with the NPA tumors. CONCLUSIONS: Our results propose that NK cells although were stimulated in advanced fibrosis with tumor, they lost their anti-tumor and anti-fibrotic activity probably due to secretions of T4 and VEFG and may explain increased risk of thyroid tumors in chronic HCV patients.

Harmonic scalpel assisted superficial parotidectomy.

OBJECTIVE: The Harmonic Scalpel (HS) has been recently widely used to perform a variety of surgical procedures. We reviewed our experience with the use of HS in superficial parotidectomy to determine the safety and efficacy of this procedure, with regard to operative time, postoperative facial nerve function, and drainage output. STUDY DESIGN: Nonrandomized retrospective review. MATERIALS AND METHODS: The medical records of all patients who underwent superficial parotidectomy for benign pathology at Shaare Zedek Medical Center from January 2006 to July 2009 were retrospectively reviewed. Patients with prior facial nerve weakness or prior parotid surgery or who had undergone concurrent neck dissection or total parotidectomy were excluded. RESULTS: Fifty-eight patients were reviewed; 26 patients underwent HS parotidectomy and 32 patients underwent conventional (cold knife) parotidectomy (control group). Harmonic Scalpel assisted parotidectomy was associated with significantly decreased length of surgery from 163.12 ± 21.8 minutes for controls to 137.3 ± 18.6 minutes in the HS assisted group (P < .05). The incidence of temporary postoperative facial nerve paresis was significantly reduced from 43% in the controls to 23% in the HS group (P < .05). No permanent facial nerve paralysis was reported. There were differences in the overall postoperative drain output between the HS and control groups, 68 ± 22.3 mL and 73.5 ± 38.2 mL, respectively, but these differences did not achieve significance. CONCLUSION: This study shows that HS assisted superficial parotidectomy for benign pathology is a safe technique and associated with reduced surgical time and incidence of temporary postoperative facial nerve paresis compared with conventional techniques.

[Fluoroscopic assisted cochlear implantation in children with inner ear malformations].

BACKGROUND: Cochlear implants are the treatment of choice for individuals with severe to profound sensorineural hearing loss. In most cases, the anatomy is normal and the insertion of the electrode-array is straightforward, complete and in the correct position. In the presence of inner-ear malformations, the risk of an intra or extra-cochlear malpositioned electrode-array increases. OBJECTIVES: To describe the technique of fluoroscopic assisted cochlear implantation in children with severe inner-ear malformations and present the results with respect to the number of active electrodes and function. METHODS: Fifteen fluoroscopy assisted implantations in 9 children were conducted at the Shaare Zedek Cochlear Implant Center between 2009-1014. All implanted ears had severe anatomic malformations. Mean implantation age was 3.5 years (range 1-11). Six children underwent sequential bilateral implantation. Two children underwent revision surgery due to a malpositioned electrode initially implanted without fluoroscopy at other centers. RESULTS: There was no radiologic or electro-physiologic evidence of kinking, bending or electrode damage in all 15 implantations. Complete insertion was achieved in all ears except one with partial insertion. There were no extra-cochlear or intrameatal placements. In 9 ears, all electrodes were active at switch-on and in the remaining, 15-20 were active. In all ears the Ling-6 sounds were detected and in 13 they were also identified. CONCLUSION: Fluoroscopy is an effective tool in complex cochlear implant surgeries and its use is simple and safe. As demonstrated in this study, with fluoroscopy assistance, good results are achieved in children with inner-ear malformations.

Redefining parapharyngeal space infections.

OBJECTIVES: Our intent was to review the clinical signs, computed tomography (CT) scans, treatment, and outcome of parapharyngeal space infections (PPIs), and to define 2 types of infections of the parapharyngeal space (PPS) according to the location of the infectious process. METHODS: We performed a retrospective analysis of patients hospitalized in a tertiary university hospital with a diagnosis of PPI, abscess, or deep neck abscess between 1988 and 2004. Files and CT scans were reviewed after classification into 2 groups: 1) infection located in the posterior part of the PPS (PostPPI); and 2) infection located in the anterior part of the PPS (AntPPI). RESULTS: Twenty-two patients had a PostPPI; their ages ranged from 10 months to 24 years. Five patients underwent surgical drainage, and 17 others were treated solely with intravenous antibiotic therapy. No pus was found during surgery in 2 patients. The average time of hospitalization was 10 days. Only 1 complication (aspiration pneumonia) was observed. Seven patients had an AntPPI; their ages ranged from 1.5 years to 65 years. All patients underwent surgical drainage, and pus was detected in all cases. The average time of hospitalization was 35 days. Complications (septic shock, respiratory arrest, mediastinitis, pleural empyema, pericarditis) were observed in 4 patients. CONCLUSIONS: The term "parapharyngeal abscess" was assigned long before the CT scan era, and was based on physical examination and plain film radiology. In essence, the entity PPS "abscess" or "infection" is composed of 2 different disorders. Infection located in the posterior part of the PPS with no invasion into the parapharyngeal fat and with no extension into other cervical spaces except the adjacent retropharyngeal space may be termed posterior parapharyngeal infection or parapharyngeal lymphadenitis. This is a relatively benign condition, and nonsurgical treatment should be considered. Infection involving the parapharyngeal fat may be termed parapharyngeal abscess or deep neck abscess. Diffusion into the mediastinum and other severe complications are frequent. Urgent surgical drainage is therefore mandatory.

Packing in endoscopic sinus surgery: is it really required?

OBJECTIVE: The aim of this study was to evaluate the routine use of packing or local hemostatic agents in endoscopic sinus surgery (ESS). METHODS: Packing and/or hemostatic agents were used only when necessary in 100 consecutive adult ESS patients in a tertiary academic hospital. Necessity for packing the nose after excessive bleeding was analyzed in relation to demographic characteristics, medical history, previous surgeries, current surgical procedure, type of anesthesia, and amount of intraoperative bleeding. RESULTS: Three patients who required packing because of other reasons (such as bolstering of mucosa) were excluded from the study. The remaining 97 patients included 61 males and 36 females between the ages of 16 to 86 (mean 44). Forty-nine patients underwent only ESS, 40 ESSs associated with nasal polypectomy, and 8 underwent other endoscopic procedures. Fifty-four underwent the operation under general anesthesia and 43 under local anesthesia. Intraoperative blood loss was less than 30 mL in 82 patients (85%), 30 to 50 mL in 11 (11%), and more than 50 mL in 4 (4%). In 89 patients (92%), packing or a hemostatic agent was not used. No patient had bleeding complications postoperatively. A comparison between patients who required packing to those who did not showed that the only statistically significant associations related to general anesthesia (P = 0.0082) and to the amount of intraoperative bleeding (P < 0.001). CONCLUSIONS: Most ESS procedures can be managed without packing or any other hemostatic measures. Local anesthesia, use of local vasoconstrictors, and careful operative technique minimize the need for nose packing, thus reducing patient's discomfort, postoperative complications, and cost of surgery.

Nasal airflow and olfactory function after the repair of cleft palate (with and without cleft lip).

OBJECTIVE: The objective of this study was to examine nasal airflow and olfactory functions in patients with repaired cleft palate compared with matching normal controls. STUDY DESIGN: The all-cleft group consisted of 25 patients with hard palate cleft comprising 15 patients with unilateral cleft palate and lip (UCLP); 2 with CP but no cleft lip (UCLP subgroup) and 8 patients with bilateral cleft lip and palate (BCLP subgroup). All had had surgical correction of the palate in infancy. The control group consisted of 20 nonaffected orthodontic patients. The median age of both groups was 14 years. The tests included the following: (1) nasal airflow measured by anterior rhinomanometry, (2) smell threshold for isoamyl-acetate determined using a 3-way forced choice method, (3) a self-administered questionnaire regarding the subjective perception of smell sense function, and (4) orthonasal and retronasal smell identification (correct/incorrect) and hedonics using visual analog scale (VAS). RESULTS: The respective test results follow. (1) When compared with the control group, the total airflow in the UCLP subgroup was significantly lower especially on the affected side; while in the BCLP subgroup it was lower than in the control group bilaterally. No significant difference was found between the cleft side of UCLP and BCLP subgroups. (2) The smell threshold of the UCLP subgroup was significantly higher than that of the control group and BCLP subgroup. No significant differences were found between right and left nostrils within the BCLP patients and between them and the control group. (3) No difference was found between the groups regarding the subjective perception of smell. (4) No significant differences were found between the UCLP and BCLP subgroups and between the all-cleft group and the control group, except for one item, regarding orthonasal and retronasal smell identification and hedonics. CONCLUSION: Although nasal airflow is significantly lower and the smell threshold higher on the cleft side, the day-to-day function of the sense of smell of cleft patients is similar to that of normal controls.

Purulent chondritis of the laryngeal framework cartilages.

This manuscript reports on our experience with purulent chondritis of the laryngeal cartilages (PCLC), an entity that has not yet been described. Three patients had a diagnosis of PCLC. The probable causes were relapsing polychondritis, a previous prolonged intubation, and an idiopathic cause. The patients suffered from hoarseness and inspiratory stridor for 1 to 3 months before diagnosis. None complained of pain in the neck. Laryngoscopy showed supraglottic edema. A computed tomography scan revealed abscess formation between the intact inner and outer perichondria of the thyroid cartilage. The treatment included rigid endoscopy, external incision and drainage, and prolonged medical therapy. The culture results were Staphylococcus aureus in the first 2 cases and Aspergillus fumigatus in the third. The second patient (in whom the cricoid cartilage was also affected) required emergency tracheotomy. The other 2 patients did not require airway intervention. The rarity of PCLC and the relatively mild symptoms require a high index of suspicion for its diagnosis.

A new surgical technique for primary closure of long-term tracheostomy.

OBJECTIVES: To delineate a technique that avoids the complications associated with surgical closure of long-term or permanent tracheostomy (LTT). Study design A case series that describes the technique and clinical outcomes. METHODS: Thirty-seven of 300 patients with a previously established LTT underwent primary surgical closure of their stoma after their underlying disease had been resolved. The surgical technique combined a turnover flap with medialization of fibroadipose tissue, followed by additional closure with an advancement skin flap. RESULTS: After a mean follow-up of 3.2 years, no patient developed major complications. Four patients developed minor complications, which responded to conservative treatment. In all patients, the functional results were satisfactory, as were the cosmetic results, with the exception of 1 case. None required re-tracheostomy. CONCLUSION AND SIGNIFICANCE: This simple and reliable new surgical technique for closing LTT avoids the potential failures and complications encountered in previously published procedures.

Cochlear activation at low sound intensities by a fluid pathway.

In order to assess the mechanisms responsible for cochlear activation at low sound intensities, a semi-circular canal was fenestrated in fat sand rats, and in other experiments a hole was made in the bone over the scala vestibuli of the first turn of the guinea-pig cochlea. Such holes, which expose the cochlear fluids to air, provide a sound pathway out of the cochlea which is of lower impedance than that through the round window. This should attenuate the pressure difference across the cochlear partition and thereby reduce the driving force for the base-to-apex traveling wave along the basilar membrane. The thresholds of the auditory nerve brainstem evoked responses (ABR) and of the cochlear microphonic potentials were not affected in the fenestration experiments. In addition, holes in the scala vestibuli of the first turn did not cause ABR threshold elevations. These results contribute further evidence that at low sound intensities the outer hair cells are probably not activated by a base-to-apex traveling wave along the basilar membrane. Instead it is possible that they are excited directly by the alternating condensation/rarefaction fluid pressures induced by the vibrations of the stapes footplate. The activated outer hair cells would then cause the localized basilar membrane movement.