bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of acute thyroxin depletion on hearing in humans
Authors: Mra Zan , Wax Mark K. 
Published: November 2003

AbstractObjective: To study the physiologic effect of acute thyroid hormone depletion on hearing and the function of outer hair cells.Design: Audiologic and otoacoustic emission testing of subjects undergoing total thyroidectomy before surgery and up to 6 weeks after surgery. Magnitude of thyroxin depletion monitored by serum thyroid‐stimulating hormone levels.Setting: Hearing research laboratory at a state university.Subjects: Ten patients undergoing total thyroidectomy.Main Outcome Measures: Detection of hearing loss on audiogram and decrease or disappearance of otoacoustic emissions as a result of acute thyroxin depletion.Results: No significant changes in the audiogram and otoacoustic emission configurations were detected, although thyroid‐stimulating hormone levels became elevated after total thyroidectomy.Conclusion: Although thyroid hormone is thought to play a role in the physiology of hearing in humans, no deleterious effects on hearing can be identified up to 6 weeks after thyroxin depletion
Cochlear reimplantation
Authors: Balkany Thomas J. , Hodges Annelle V. , Gómez‐Marín Orlando , Bird Philip A. , Dolan‐Ash Shelly , Butts Stacy , Telischi Mee Fred F. , Lee David 
Published: November 2003

AbstractObjective: A small number of multichannel cochlear implant (CI) recipients require reimplantation. This study describes the causes of failure, surgical technique, and hearing outcomes in a consecutive series of 16 patients undergoing reimplantation of multichannel devices. We hypothesize that reimplantation is safe and that hearing results are at least as good as those measured following primary implantation. Study Design: Retrospective analysis of consecutive clinical series. Methods: Chart analysis of 191 consecutive CI operations performed at the University of Miami Ear Institute between 1990 and 1997 revealed 16 patients who received a second multichannel device. All but one had a minimum follow‐up of 1 year after reimplantation. Ten of these patients had initial implantation performed by us, and six were initially operated on elsewhere. Main outcomes of the initial procedure were compared with those of the reimplantation, including electrode insertion length, number of channels programmed, and audiometric results. In addition, cause of failure and relevant surgical findings at the second procedure are described. Results: There were no surgical complications after reimplantation surgery. Device failure was the most frequent cause for reimplantation. Time between initial implantation and failure ranged from 0 to 46 months (mean, 22.4 mo; median, 23 mo). Common intraoperative findings include mastoid fibrosis, bone growth at the cochleostomy, and skin flap breakdown. Following reimplantation, mean length of insertion, number of channels actively programmed, and speech recognition scores were at least as good as findings before initial implant failure. Conclusion: CI reimplantation is safe and effective.
Limitations of adenovirus‐mediated interleukin‐2 gene therapy for oral cancer
Authors: O'Malley Bert W. , Li Daqing , Buckner Alyson , Duan Ling , Woo Savio L.C. , Pardoll Drew M. 
Published: November 2003

AbstractObjective/Hypothesis: Adenoviral interleukin‐2 (AdV‐IL‐2) gene therapy has previously not proven effective in treating established murine oral cancer. We hypothesize that the intratumoral level of IL‐2 expression is a major limiting factor in treatment outcome. Methods: A microscopic disease and established oral cancer murine model was used to test this hypothesis. IL‐2 gene transfer was performed with a recombinant adenovirus vector. Results: Tumor cells were transduced in vitro with AdV‐IL‐2 and subsequently implanted into the floor of the mouth in C3H/ HeJ mice. IL‐2 expression in vitro ranged from 990 to 1,050 pg/106 tumor cells. This microscopic disease treatment resulted in either complete tumor regression or a dramatic decrease in tumor progression. Cytolytic T‐cell (CTL) assays demonstrated a predominance of CD8‐specific, T‐cell–mediated tumor killing. Reducing IL‐2 expression by half with a mixture of 1:1 transduced to nontransduced tumor cells eliminated the antitumor effect and decreased the CTL response. These findings support the presence of a critical “threshold” of IL‐2 expression. Adenovirus repurification and amplification allowed isolation of a twofoldhigher‐titer AdV‐IL‐2 vector. Treatment of established tumors with the higher‐titer AdV‐IL‐2 at a new maximal dose of 1.4 × 109 plaque‐forming units (pfu) increased in vivo IL‐2 expression to 1,127 pg/106 cells and generated a significant antitumor response. Complete regression of established tumors, however, could not be achieved, and we noted a decrease in IL‐2 expression well below the threshold at 1 week after treatment. Upon repeat maximal AdV‐IL‐2 injection in vivo, a greater antitumor effect and increased CTL response was seen, but also, 28% of the animals died of IL‐2 toxicity. Conclusion: Although limited by expression and toxicity as a single‐treatment strategy for established tumors, AdV‐IL‐2 gene therapy should be considered a potential component of combination therapy strategies.
Combined intratumor cisplatinum injection and Nd:YAG laser therapy
Authors: Graeber Ines P. , Eshraghi Adrien A. , Paiva Marcos B. , Paek Woo H. , Castro Dan J. , Jovanovic Sergije , Scherer Hans , Soudant Jacques , Saxton Romaine E. 
Published: November 2003

AbstractObjectives/Hypothesis: Interstitial laser therapy (ILT) has become useful for tumor palliation in patients with advanced head and neck cancer. Cisplatinum chemotherapy also is a frequent adjuvant treatment for recurrent tumors, but systemic toxicity limits application. Intratumor cisplatinum injection combined with ILT may improve therapy of these recurrent tumors with reduced toxicity. Study Design: Prospective. Tumor transplants were injected with cisplatinum in a gel implant before ILT to evaluate treatment response and toxicity in a preclinical study. Methods: UCLA‐P3 human squamous cell carcinoma tumors were grown as subcutaneous transplants in nude mice and treated by intratumor injection of 2 mg/mL cisplatinum in a slow‐release, collagen‐based gel carrier 4 hours before interstitial implantation of Nd:YAG laser fiberoptics to induce local tumor hyperthermia. Treatment efficacy and toxicity were followed for 12 weeks after combined drug and laser therapy compared with ILT alone. Results: Combined cisplatinum gel and ILT was a significant improvement (P < .01 by chi‐square test) and induced 57% complete responses without regrowth in 21 transplanted tumors compared with only 24% in 21 tumors after ILT alone during 12‐week follow‐up. Recurrences in both cases appeared to result from nonuniform laser energy delivery within tumors via the implanted fiberoptic tip. Conclusions: The results of this experimental combined cisplatinum and ILT study suggest it may be possible to improve treatment of advanced head and neck cancer by intratumor injection of gel implants containing the drug followed by interstitial Nd:YAG laser hyperthermia.
Evidence of mast cell activity in the middle ears of children with otitis media with effusion
Authors: Hurst David S. , Amin Kawa , Sevéus Lahja , Venge Per 
Published: November 2003

AbstractObjectives: This is the first study to report the presence of tryptase, a reflection of mast cell activity, in chronic middle ear effusion of patients whose atopic status was characterized. Design and Methods: Mediator activity of mast cells and eosinophils was measured prospectively from effusion of 33 randomly selected patients and 5 control subjects with chronic otitis media with effusion (OME). Atopy was determined by enzyme‐linked immunosorbent assay. Middle ear biopsies from a second group of 8 OME patients and 4 controls were fixed in plastic and stained immunohistochemically for mast cells. Results: Sixty‐one percent of patients had extensive activation of mast cells in their middle ears. Among those with elevated tryptase in their effusion, 95.6% were atopic and 94.7% also had elevated levels of effusion eosinophilic cationic protein (ECP). Tryptase levels were elevated only in the effusion of atopic patients, as compared with 5 controls (P < .01). Mast cells were present in 6 of 8 OME ears and absent in all 4 normal ears. Conclusion: Mast cells and its mediator tryptase, both indicators of a Th2‐driven immune response, are present in a majority of ears that have chronic effusion. These findings support the hypothesis that middle ear mucosa is capable of an allergic response and that the inflammation within the middle ear of most OME patients is allergic in nature.
A technique of mastoidectomy and meatoplasty that minimizes factors associated with a discharging mastoid cavity
Authors: Wormald Peter John , Van Hasselt C. Andrew 
Published: November 2003

AbstractObjectives: To present and assess a surgical technique designed to minimize the known causes of a discharging mastoid cavity.Study Design: A temporal bone dissection to establish the anatomical relationships on which the surgical technique is based. A presentation of the proposed surgical technique and a prospective assessment of the technique in twenty consecutive mastoidectomies.Methods: Five temporal bone dissections were performed to establish the relationship between the chorda tympani and the facial nerve when these structures are approached from above. The surgical technique is presented and the mastoid cavities of twenty consecutive patients assessed. The assessment included measurement of the facial ridge height, “kidney‐shape” of the cavity, size of the cavity, size of the meatus, and state of the tympanic membrane.Results: In the temporal bone dissections the vertical height between the chorda tympani and the facial nerve at 3/9 o'clock was a mean of 2.01 mm. Nineteen of the 20 consecutive mastoid cavities (95%) performed with the presented technique remained well healed and dry. The mean facial ridge height was 2.7 mm at 3/9 o'clock and 4.8 mm at 6 o'clock. The kidney‐shaped measurement was 1.45 mm. The mean size of the cavities was 2.6 mm and 18 of the 20 patients (90%) had an intact tympanic membrane. The mean largest diameter of the meatus was 10.1 mm.Conclusions: The surgical technique presented produces a mastoid cavity with a low facial ridge and oval shape. These two factors have been previously identified as important in the outcome of mastoid surgery.
A clinical study on the magnetic stimulation of the facial nerve
Authors: Yamakawa Takuya , Yoshikawa Hiroshi , Arai Akira , Miyazaki Toyo , Ichikawa Ginichiro 
Published: November 2003

AbstractObjectives: A clinical study on the usefulness of magnetic stimulation of the facial nerve, with special attention paid to the selection of the coil shape and stimulation procedures. Study Design: The subjects consisted of 55 patients with Bell's palsy, 1 patient with a cerebellopontine angle (CPA) tumor, 1 patient with multiple sclerosis (MS), and 30 normal subjects. Three types of coils were used in this study; a 90‐mm large single coil, a 40‐mm small single coil, and a 20‐mm small double coil. Methods: The compound muscle action potentials (CMAPs) and long latency response were evoked by transcranial magnetic stimulation (TMS) with a 90‐mm large single coil. The 40‐mm small single coil was used to test blink reflex by aiming it at the supraorbital nerve as the target site. The subcutaneous activation of the infra‐auricular facial nerve was performed with the 20‐mm double coil. Results: The reproducible CMAP and long latency responses were obtained from normal subjects with TMS. However, responses were observed only in patients with relatively mild Bell's palsy. The magnetic stimulation—evoked responses reflected the brainstem function in the patients with a CPA tumor and MS. Conclusion: Although magnetic stimulation remains inferior to conventional electric stimulation in some sense and requires further study, this method is potentially useful because it can stimulate the facial nerve continuously from the cortex to the periphery and can effectively evoke responses reflecting the brainstem function.
An Integrated Theory of the No‐Reflow Phenomenon and the Beneficial Effect of Vascular Washout on No‐Reflow
Authors: Calhoun Karen H. , Tan Luke , Seikaly Hadi 
Published: November 2003

AbstractObjectives: No‐reflow is failure of perfusion in free tissue transfer despite adequate arterial inflow. The objectives of this study were to construct a theory of interactive mechanisms of the no‐reflow phenomenon and to determine whether preischemic vascular washout could increase flap ischemia tolerance.Study Design: The evidence for the role of various mechanisms in the development of no‐reflow is reviewed, and an integrated network proposed. A ratgroin free flap model is used to test preischemic vascular washout with normal saline, heparinized normal saline, lactated Ringer's solution, Tis‐U‐Sol, and Viaspan.Methods: The mean ischemia tolerance of this flap without any therapeutic intervention was first determined, using 22 animals. An additional 50 animals were used to compare with the control group the ischemia tolerance of flaps washed out with the above fluids before their ischemic period.Results: The critical ischemia time 50 (time after which half of the flaps are expected to survive and half, die) of the untreated flap is 23.4 hours in this model (P < .05). Flaps washed out with normal saline or lactated Ringer's solution have significantly worse ischemia tolerance (P < .0001). Flaps washed out with Tis‐U‐Sol or Viaspan behave similarly to the control group (P > .57). Flaps receiving preischemic washout with heparinized normal saline (4,000 units/L) had a significantly better outcome than the control group (P < .027).Conclusions: Preischemic washout with normal saline, lactated Ringer's solution, or heparinized Tis‐U‐Sol is detrimental for flap survival after ischemia, Tis‐U‐Sol‐ and Viaspan‐treated flaps do have ischemia tolerance similar to the control group, and flaps washed out with heparinized normal saline have a survival advantage in this model.
Surgical Experience and Complications During Endonasal Sinus Surgery
Authors: Keerl Rainer , Stankiewicz James , Weber Rainer , Hosemann Werner , Draf Wolfgang 
Published: November 2003

AbstractObjective/Hypothesis: The introduction of optical aids for endonasal sinus surgery has not produced the expected drop in the rate of serious intraoperative complications.Study Design/Methods:
1. Retrospectively, consecutive procedures of different surgeons were analyzed in regard to major complications (periorbital injury, orbital lesion, dural injury, endocranial lesion, damage to the internal carotid artery). The chronological distribution was transformed into a personal learning curve. 2. From our own experience and as surveyors, we analyzed the experiences of surgeons having encountered severe complications and compared them with the above‐mentioned learning curve.Result: In total, 1,500 operations carried out by five surgeons with 16 serious complications were assessed. For the learning curve, the following stages were defined. stage I: greatest risk of complication, with dural injury (1st to 30th operation); stage II, slighter risk of complication, with frequent periorbital injuries (31st to 180th operation); and stage III, least risk, corresponding to an experienced surgeon. Serious complications occur most frequently among experienced surgeons.Conclusion: The beginner enjoys the most effective type of assistance, in the form of personal guidance of an experienced surgeon who is constantly present during the first 30 operations, and who should then be readily available during the next 70 operative procedures. The use of multimedia software appears to be helpful, though its actual value still remains to be determined. The experienced surgeon in particular must be willing to exercise repeated self‐criticism to keep his or her rate of complications to a minimum.
Interaction Between Fibronectin and Eosinophils in the Growth of Nasal Polyps
Authors: Nakagawa Takayuki , Yamane Hideo , Shigeta Toshinobu , Takashima Tadayoshi , Nakai Yoshiaki 
Published: November 2003

AbstractObjectives: The aim of this study was to determine roles of fibronectin and eosinophils in the etiology of nasal polyposis.Study Design: We designed a cohort study of cases with nasal polyposis. Sampled nasal polyps were differentiated by their histopathologic characteristics, and compared by size and computed tomography (CT) stage.Methods: The size of nasal polyps was determined on the basis of the endoscopic findings, and the extent of sinusitis was evaluated by CT staging. Nasal polyp samples were taken from 82 patients during ethmoidectomy and differentiated by morphologic characteristics, infiltration cell types, or fibronectin positivity. Then their sizes and CT stages were compared. In addition, correlation among these histological characteristics was analyzed.Results: Nasal polyps showing edematous morphology, eosinophil infiltration, or fibronectin expression were significantly large in size. Concerning CT stages, only the infiltration cell type showed a significant difference. Significant correlation among edematous morphology, eosinophil infiltration, and fibronectin expression was also recognized.Conclusions: These findings suggest that interaction between eosinophils and fibronectin may play a role in edema formation, which contributes to the growth of nasal polyps.
Gustatory Otalgia and Wet Ear Syndrome: A Possible Cross‐Innervation After Ear Surgery
Authors: Saito Haruo 
Published: November 2003

AbstractHypothesis: The chorda tympani and Arnold's nerves have close approximation to each other and their cross‐innervation is possible after ear surgery.Study Design: A retrospective study was performed with a temporal bone pathology case and two clinical cases as representatives of such a possibility. Patients had severe otalgia and wet ear during gustatory stimulation.Methods: A temporal bone pathology case was studied under a light microscope. Earache and/or wet ear were provoked during gustatory stimulation. Wet ear was tested with iodine‐starch reaction after the subject tasted lemon juice.Results: The temporal bone specimen has clusters of regenerated fibers in the tympanic cavity in the area of the chorda tympani and Arnold's nerves, suggesting a possibility of mixing. There are regenerated fibers in the iter chordae anterius, showing successful bridging of the chorda tympani nerves across a long gap. Detachment of the skin over the operated mastoid bowl obscured signs in one clinical case. Another clinical case of gustatory wet ear showed objective evidence of cross‐innervation with iodine‐starch reaction.Conclusion: The detachment procedure and iodine‐starch reaction were the proofs that the signs were related to regenerated fibers. This is the first report of gustatory otalgia and wet ear after ear surgery.
Age at Implantation: Its Importance in Pediatric Cochlear Implantation
Authors: Nikolopoulos Thomas P. , O'Donoghue Gerard M. , Archbold Sue 
Published: November 2003

AbstractObjective: To assess the influence of age at implantation on speech perception and speech intelligibility following pediatric cochlear implantation.Study Design: A prospective study was undertaken on a consecutive group of 126 congenital and prelingually deaf children up to 4 years after implantation. The study group was confined to prelingually deaf children less than 7 years of age at the time of implantation. All had implantation with the same multichannel cochlear implant system. No child was lost to follow‐up, and there were no exclusions from the study.Methods: The Iowa Matrix Closed Set Sentence test, connected discourse tracking, categories of auditory performance, and speech intelligibility rating were used to assess the speech perception (closed and open set) and speech intelligibility of the children with implants. Regression analysis and Spearman rank correlation coefficients were used to assess the correlation between the outcome measures with age at implantation. The setting was a tertiary referral pediatric cochlear implant center in the United Kingdom.Results: Age at implantation positively correlated with preimplantation assessment performance and with most of the outcome measures up to 24 months following implantation. However, at the 3‐ and 4‐year intervals following implantation, age at implantation was found to be a strong negative predictor of all the outcomes studied (correlation coefficients ranging from −0.44 to −0.58, all statistically significant [P < .05]).Conclusions: The results of the present study provide strong evidence that prelingually deaf children should receive implants as early as possible to facilitate the later development of speech perception skills and speech intelligibility and thus maximize the health gain from the intervention. However, because of the wide variation in individual outcomes, age alone should not be used as a criterion to decide implant candidacy.
Effects of Immunosuppression on the Development of Cochlear Disease in the MRL‐Faslpr Mouse
Authors: Ruckenstein Michael J. , Sarwar Armughan , Hu Lydia , Shami Halla , Marion T. N. 
Published: November 2003

AbstractObjectives: The MRL‐Faslpr mouse, an animal that spontaneously develops multisystemic autoimmune disease, has been proposed as model of immune‐mediated inner ear disease. Previous studies revealed that this mouse manifested elevated auditory brainstem response thresholds, hydropic degeneration of strial cells, and antibody deposition within strial capillaries. As the etiology of the observed strial disease may be immune, genetic, or uremic, a study was designed to attempt to delineate between these possible etiologic factors.Study Design: Prospective, controlled animal study.Methods: Dexamethasone, which is known to suppress autoantibody production and glomerulonephritis in these animals, was administered systemically on a daily basis to experimental animals, beginning at 6 weeks of age. Control animals received no treatment. Animals were allowed to age, with control animals predictably manifesting systemic disease at 20 weeks of age, at which point all animals were sacrificed.Results: Animals receiving dexamethasone treatment manifested a significant reduction in serum immunoglobulin levels, lymphoid hyperplasia, and a significant improvement in the level of renal function. However, morphologic analysis revealed a persistence of strial disease despite the elimination of strial antibody deposition.Conclusion: The results of this experiment support the hypothesis that genetic mechanisms may be responsible for the observed strial disease. Further studies are under way to confirm these findings.