Clinical Practice Guideline: Tonsillectomy in Children (Update)

OBJECTIVE

This update of a 2011 guideline developed by the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations on the pre-, intra-, and postoperative care and management of children 1 to 18 years of age under consideration for tonsillectomy. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil, including its capsule, by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Tonsillectomy is one of the most common surgical procedures in the United States, with 289,000 ambulatory procedures performed annually in children <15 years of age based on the most recent published data. This guideline is intended for all clinicians in any setting who interact with children who may be candidates for tonsillectomy.

PURPOSE

The purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing children under consideration for tonsillectomy and to create explicit and actionable recommendations to implement these opportunities in clinical practice. Specifically, the goals are to educate clinicians, patients, and/or caregivers regarding the indications for tonsillectomy and the natural history of recurrent throat infections. Additional goals include the following: optimizing the perioperative management of children undergoing tonsillectomy, emphasizing the need for evaluation and intervention in special populations, improving the counseling and education of families who are considering tonsillectomy for their children, highlighting the management options for patients with modifying factors, and reducing inappropriate or unnecessary variations in care. Children aged 1 to 18 years under consideration for tonsillectomy are the target patient for the guideline. For this guideline update, the American Academy of Otolaryngology-Head and Neck Surgery Foundation selected a panel representing the fields of nursing, anesthesiology, consumers, family medicine, infectious disease, otolaryngology-head and neck surgery, pediatrics, and sleep medicine.

KEY ACTION STATEMENTS

The guideline update group made strong recommendations for the following key action statements (KASs): (1) Clinicians should recommend watchful waiting for recurrent throat infection if there have been <7 episodes in the past year, <5 episodes per year in the past 2 years, or <3 episodes per year in the past 3 years. (2) Clinicians should administer a single intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. (3) Clinicians should recommend ibuprofen, acetaminophen, or both for pain control after tonsillectomy. The guideline update group made recommendations for the following KASs: (1) Clinicians should assess the child with recurrent throat infection who does not meet criteria in KAS 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergies/intolerance, PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis), or history of >1 peritonsillar abscess. (2) Clinicians should ask caregivers of children with obstructive sleep-disordered breathing and tonsillar hypertrophy about comorbid conditions that may improve after tonsillectomy, including growth retardation, poor school performance, enuresis, asthma, and behavioral problems. (3) Before performing tonsillectomy, the clinician should refer children with obstructive sleep-disordered breathing for polysomnography if they are <2 years of age or if they exhibit any of the following: obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or mucopolysaccharidoses. (4) The clinician should advocate for polysomnography prior to tonsillectomy for obstructive sleep-disordered breathing in children without any of the comorbidities listed in KAS 5 for whom the need for tonsillectomy is uncertain or when there is discordance between the physical examination and the reported severity of oSDB. (5) Clinicians should recommend tonsillectomy for children with obstructive sleep apnea documented by overnight polysomnography. (6) Clinicians should counsel patients and caregivers and explain that obstructive sleep-disordered breathing may persist or recur after tonsillectomy and may require further management. (7) The clinician should counsel patients and caregivers regarding the importance of managing posttonsillectomy pain as part of the perioperative education process and should reinforce this counseling at the time of surgery with reminders about the need to anticipate, reassess, and adequately treat pain after surgery. (8) Clinicians should arrange for overnight, inpatient monitoring of children after tonsillectomy if they are <3 years old or have severe obstructive sleep apnea (apnea-hypopnea index ≥10 obstructive events/hour, oxygen saturation nadir <80%, or both). (9) Clinicians should follow up with patients and/or caregivers after tonsillectomy and document in the medical record the presence or absence of bleeding within 24 hours of surgery (primary bleeding) and bleeding occurring later than 24 hours after surgery (secondary bleeding). (10) Clinicians should determine their rate of primary and secondary posttonsillectomy bleeding at least annually. The guideline update group made a strong recommendation against 2 actions: (1) Clinicians should not administer or prescribe perioperative antibiotics to children undergoing tonsillectomy. (2) Clinicians must not administer or prescribe codeine, or any medication containing codeine, after tonsillectomy in children younger than 12 years. The policy level for the recommendation about documenting recurrent throat infection was an option: (1) Clinicians may recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year, at least 5 episodes per year for 2 years, or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and ≥1 of the following: temperature >38.3°C (101°F), cervical adenopathy, tonsillar exudate, or positive test for group A beta-hemolytic streptococcus.

DIFFERENCES FROM PRIOR GUIDELINE

(1) Incorporating new evidence profiles to include the role of patient preferences, confidence in the evidence, differences of opinion, quality improvement opportunities, and any exclusion to which the action statement does not apply. (2) There were 1 new clinical practice guideline, 26 new systematic reviews, and 13 new randomized controlled trials included in the current guideline update. (3) Inclusion of 2 consumer advocates on the guideline update group. (4) Changes to 5 KASs from the original guideline: KAS 1 (Watchful waiting for recurrent throat infection), KAS 3 (Tonsillectomy for recurrent infection with modifying factors), KAS 4 (Tonsillectomy for obstructive sleep-disordered breathing), KAS 9 (Perioperative pain counseling), and KAS 10 (Perioperative antibiotics). (5) Seven new KASs: KAS 5 (Indications for polysomnography), KAS 6 (Additional recommendations for polysomnography), KAS 7 (Tonsillectomy for obstructive sleep apnea), KAS 12 (Inpatient monitoring for children after tonsillectomy), KAS 13 (Postoperative ibuprofen and acetaminophen), KAS 14 (Postoperative codeine), and KAS 15a (Outcome assessment for bleeding). (6) Addition of an algorithm outlining KASs. (7) Enhanced emphasis on patient and/or caregiver education and shared decision making.

Clinical Practice Guideline: Tonsillectomy in Children (Update)-Executive Summary

OBJECTIVE

This update of a 2011 guideline developed by the American Academy of Otolaryngology-Head and Neck Surgery Foundation provides evidence-based recommendations on the pre-, intra-, and postoperative care and management of children 1 to 18 years of age under consideration for tonsillectomy. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil, including its capsule, by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Tonsillectomy is one of the most common surgical procedures in the United States, with 289,000 ambulatory procedures performed annually in children <15 years of age, based on the most recent published data. This guideline is intended for all clinicians in any setting who interact with children who may be candidates for tonsillectomy.

PURPOSE

The purpose of this multidisciplinary guideline is to identify quality improvement opportunities in managing children under consideration for tonsillectomy and to create explicit and actionable recommendations to implement these opportunities in clinical practice. Specifically, the goals are to educate clinicians, patients, and/or caregivers regarding the indications for tonsillectomy and the natural history of recurrent throat infections. Additional goals include the following: optimizing the perioperative management of children undergoing tonsillectomy, emphasizing the need for evaluation and intervention in special populations, improving the counseling and education of families who are considering tonsillectomy for their children, highlighting the management options for patients with modifying factors, and reducing inappropriate or unnecessary variations in care. Children aged 1 to 18 years under consideration for tonsillectomy are the target patient for the guideline. For this guideline update, the American Academy of Otolaryngology-Head and Neck Surgery Foundation selected a panel representing the fields of nursing, anesthesiology, consumers, family medicine, infectious disease, otolaryngology-head and neck surgery, pediatrics, and sleep medicine.

KEY ACTION STATEMENTS

The guideline update group made strong recommendations for the following key action statements (KASs): (1) Clinicians should recommend watchful waiting for recurrent throat infection if there have been <7 episodes in the past year, <5 episodes per year in the past 2 years, or <3 episodes per year in the past 3 years. (2) Clinicians should administer a single intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. (3) Clinicians should recommend ibuprofen, acetaminophen, or both for pain control after tonsillectomy. The guideline update group made recommendations for the following KASs: (1) Clinicians should assess the child with recurrent throat infection who does not meet criteria in KAS 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergies/intolerance, PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis), or history of >1 peritonsillar abscess. (2) Clinicians should ask caregivers of children with obstructive sleep-disordered breathing and tonsillar hypertrophy about comorbid conditions that may improve after tonsillectomy, including growth retardation, poor school performance, enuresis, asthma, and behavioral problems. (3) Before performing tonsillectomy, the clinician should refer children with obstructive sleep-disordered breathing for polysomnography if they are <2 years of age or if they exhibit any of the following: obesity, Down syndrome, craniofacial abnormalities, neuromuscular disorders, sickle cell disease, or mucopolysaccharidoses. (4) The clinician should advocate for polysomnography prior to tonsillectomy for obstructive sleep-disordered breathing in children without any of the comorbidities listed in KAS 5 for whom the need for tonsillectomy is uncertain or when there is discordance between the physical examination and the reported severity of obstructive sleep-disordered breathing. (5) Clinicians should recommend tonsillectomy for children with obstructive sleep apnea documented by overnight polysomnography. (6) Clinicians should counsel patients and caregivers and explain that obstructive sleep-disordered breathing may persist or recur after tonsillectomy and may require further management. (7) The clinician should counsel patients and caregivers regarding the importance of managing posttonsillectomy pain as part of the perioperative education process and should reinforce this counseling at the time of surgery with reminders about the need to anticipate, reassess, and adequately treat pain after surgery. (8) Clinicians should arrange for overnight, inpatient monitoring of children after tonsillectomy if they are <3 years old or have severe obstructive sleep apnea (apnea-hypopnea index ≥10 obstructive events/hour, oxygen saturation nadir <80%, or both). (9) Clinicians should follow up with patients and/or caregivers after tonsillectomy and document in the medical record the presence or absence of bleeding within 24 hours of surgery (primary bleeding) and bleeding occurring later than 24 hours after surgery (secondary bleeding). (10) Clinicians should determine their rate of primary and secondary posttonsillectomy bleeding at least annually. The guideline update group made a strong recommendation against 2 actions: (1) Clinicians should not administer or prescribe perioperative antibiotics to children undergoing tonsillectomy. (2) Clinicians must not administer or prescribe codeine, or any medication containing codeine, after tonsillectomy in children younger than 12 years. The policy level for the recommendation about documenting recurrent throat infection was an option: (1) Clinicians may recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year, at least 5 episodes per year for 2 years, or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and ≥1 of the following: temperature >38.3°C (101°F), cervical adenopathy, tonsillar exudate, or positive test for group A beta-hemolytic streptococcus.

DIFFERENCES FROM PRIOR GUIDELINE

Incorporating new evidence profiles to include the role of patient preferences, confidence in the evidence, differences of opinion, quality improvement opportunities, and any exclusion to which the action statement does not apply. There were 1 new clinical practice guideline, 26 new systematic reviews, and 13 new randomized controlled trials included in the current guideline update. Inclusion of 2 consumer advocates on the guideline update group. Changes to 5 KASs from the original guideline: KAS 1 (Watchful waiting for recurrent throat infection), KAS 3 (Tonsillectomy for recurrent infection with modifying factors), KAS 4 (Tonsillectomy for obstructive sleep-disordered breathing), KAS 9 (Perioperative pain counseling), and KAS 10 (Perioperative antibiotics). Seven new KASs: KAS 5 (Indications for polysomnography), KAS 6 (Additional recommendations for polysomnography), KAS 7 (Tonsillectomy for obstructive sleep apnea), KAS 12 (Inpatient monitoring for children after tonsillectomy), KAS 13 (Postoperative ibuprofen and acetaminophen), KAS 14 (Postoperative codeine), and KAS 15a (Outcome assessment for bleeding). Addition of an algorithm outlining KASs. Enhanced emphasis on patient and/or caregiver education and shared decision making.

Clinical Practice Guideline

The American Academy of Otolaryngology—Head and Neck Surgery Foundation (AAO-HNSF) has published a supplement to this issue featuring the new Clinical Practice Guideline: Tinnitus. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose, and key action statements. The 13 recommendations developed address the evaluation of patients with tinnitus, including selection and timing of diagnostic testing and specialty referral to identify potential underlying treatable pathology. It will then focus on the evaluation and treatment of patients with persistent primary tinnitus, with recommendations to guide the evaluation and measurement of the impact of tinnitus and to determine the most appropriate interventions to improve symptoms and quality of life for tinnitus sufferers.

Clinical Practice Guideline

Objective

Tinnitus is the perception of sound without an external source. More than 50 million people in the United States have reported experiencing tinnitus, resulting in an estimated prevalence of 10% to 15% in adults. Despite the high prevalence of tinnitus and its potential significant effect on quality of life, there are no evidence-based, multidisciplinary clinical practice guidelines to assist clinicians with management. The focus of this guideline is on tinnitus that is both bothersome and persistent (lasting 6 months or longer), which often negatively affects the patient’s quality of life. The target audience for the guideline is any clinician, including nonphysicians, involved in managing patients with tinnitus. The target patient population is limited to adults (18 years and older) with primary tinnitus that is persistent and bothersome.

Purpose

The purpose of this guideline is to provide evidence-based recommendations for clinicians managing patients with tinnitus. This guideline provides clinicians with a logical framework to improve patient care and mitigate the personal and social effects of persistent, bothersome tinnitus. It will discuss the evaluation of patients with tinnitus, including selection and timing of diagnostic testing and specialty referral to identify potential underlying treatable pathology. It will then focus on the evaluation and treatment of patients with persistent primary tinnitus, with recommendations to guide the evaluation and measurement of the effect of tinnitus and to determine the most appropriate interventions to improve symptoms and quality of life for tinnitus sufferers.

Action Statements

The development group made a strong recommendation that clinicians distinguish patients with bothersome tinnitus from patients with nonbothersome tinnitus. The development group made a strong recommendation against obtaining imaging studies of the head and neck in patients with tinnitus, specifically to evaluate tinnitus that does not localize to 1 ear, is nonpulsatile, and is not associated with focal neurologic abnormalities or an asymmetric hearing loss. The panel made the following recommendations: Clinicians should (a) perform a targeted history and physical examination at the initial evaluation of a patient with presumed primary tinnitus to identify conditions that if promptly identified and managed may relieve tinnitus; (b) obtain a prompt, comprehensive audiologic examination in patients with tinnitus that is unilateral, persistent (≥ 6 months), or associated with hearing difficulties; (c) distinguish patients with bothersome tinnitus of recent onset from those with persistent symptoms (≥ 6 months) to prioritize intervention and facilitate discussions about natural history and follow-up care; (d) educate patients with persistent, bothersome tinnitus about management strategies; (e) recommend a hearing aid evaluation for patients who have persistent, bothersome tinnitus associated with documented hearing loss; and (f) recommend cognitive behavioral therapy to patients with persistent, bothersome tinnitus. The panel recommended against (a) antidepressants, anticonvulsants, anxiolytics, or intratympanic medications for the routine treatment of patients with persistent, bothersome tinnitus; (b) Ginkgo biloba, melatonin, zinc, or other dietary supplements for treating patients with persistent, bothersome tinnitus; and (c) transcranial magnetic stimulation for the routine treatment of patients with persistent, bothersome tinnitus. The development group provided the following options: Clinicians may (a) obtain an initial comprehensive audiologic examination in patients who present with tinnitus (regardless of laterality, duration, or perceived hearing status); and (b) recommend sound therapy to patients with persistent, bothersome tinnitus. The development group provided no recommendation regarding the effect of acupuncture in patients with persistent, bothersome tinnitus.

Clinical Practice Guideline

Objective. Sudden hearing loss (SHL) is a frightening symptom that often prompts an urgent or emergent visit to a physician. This guideline provides evidence-based recommendations for the diagnosis, management, and follow-up of patients who present with SHL. The guideline primarily focuses on sudden sensorineural hearing loss (SSNHL) in adult patients (aged 18 and older). Prompt recognition and management of SSNHL may improve hearing recovery and patient quality of life (QOL). Sudden sensorineural hearing loss affects 5 to 20 per 100,000 population, with about 4000 new cases per year in the United States. This guideline is intended for all clinicians who diagnose or manage adult patients who present with SHL.

Purpose. The purpose of this guideline is to provide clinicians with evidence-based recommendations in evaluating patients with SHL, with particular emphasis on managing SSNHL. The panel recognized that patients enter the health care system with SHL as a nonspecific, primary complaint. Therefore, the initial recommendations of the guideline deal with efficiently distinguishing SSNHL from other causes of SHL at the time of presentation. By focusing on opportunities for quality improvement, the guideline should improve diagnostic accuracy, facilitate prompt intervention, decrease variations in management, reduce unnecessary tests and imaging procedures, and improve hearing and rehabilitative outcomes for affected patients.

Results. The panel made strong recommendations that clinicians should (1) distinguish sensorineural hearing loss from conductive hearing loss in a patient presenting with SHL; (2) educate patients with idiopathic sudden sensorineural hearing loss (ISSNHL) about the natural history of the condition, the benefits and risks of medical interventions, and the limitations of existing evidence regarding efficacy; and (3) counsel patients with incomplete recovery of hearing about the possible benefits of amplification and hearing-assistive technology and other supportive measures. The panel made recommendations that clinicians should (1) assess patients with presumptive SSNHL for bilateral SHL, recurrent episodes of SHL, or focal neurologic findings; (2) diagnose presumptive ISSNHL if audiometry confirms a 30-dB hearing loss at 3 consecutive frequencies and an underlying condition cannot be identified by history and physical examination; (3) evaluate patients with ISSNHL for retrocochlear pathology by obtaining magnetic resonance imaging, auditory brainstem response, or audiometric follow-up; (4) offer intratympanic steroid perfusion when patients have incomplete recovery from ISSNHL after failure of initial management; and (5) obtain follow-up audiometric evaluation within 6 months of diagnosis for patients with ISSNHL. The panel offered as options that clinicians may offer (1) corticosteroids as initial therapy to patients with ISSNHL and (2) hyperbaric oxygen therapy within 3 months of diagnosis of ISSNHL. The panel made a recommendation against clinicians routinely prescribing antivirals, thrombolytics, vasodilators, vasoactive substances, or antioxidants to patients with ISSNHL. The panel made strong recommendations against clinicians (1) ordering computerized tomography of the head/brain in the initial evaluation of a patient with presumptive SSNHL and (2) obtaining routine laboratory tests in patients with ISSNHL.

Laser projection imaging for measurement of pediatric voice

OBJECTIVES/HYPOTHESIS

The aim of the study was to present the development of a miniature laser projection endoscope and to quantify vocal fold length and vibratory amplitude of the pediatric glottis using high-speed digital imaging coupled with the laser endoscope.

STUDY DESIGN

For this prospective study, absolute measurement of entire vocal fold length, membranous length of the vocal fold, and vibratory amplitude during phonation were obtained in one child (9 years old), one adult male (36 years old), and one adult female (20 years old) with the use of high-speed digital imaging, coupled with a custom-developed laser projection endoscope.

METHODS

The laser projection system consists of a module slip-fit sleeve with two 3-mW 650-nm laser diodes in horizontal orientation separated by a distance of 5 mm. Calibration involved projecting the laser onto grid patterns at depths ranging from 6 to 10 cm and tilt angles of 15 to -5 degrees to obtain pixel-to-millimeter conversion templates. Measurements of vocal fold length and vibratory amplitude were extracted based on methods of image processing.

RESULTS

The system demonstrated a method for estimating vocal fold length and vibratory amplitude with a single laser point with high measurement precision. First measurements of vocal fold length (6.8 mm) and vibratory amplitude (0.25 mm) during phonation in a pediatric participant are reported.

CONCLUSIONS

The proposed laser projection system can be used to obtain absolute length and vibratory measurements of the pediatric glottis. The projection system can be used with stroboscopy or high-speed digital imaging systems with a 70-degree rigid endoscope.

Clinical Practice Guideline: Sudden Hearing Loss

Program Description: The miniseminar will consist of a lively panel discussion on the evidence-based recommendations for the diagnosis and treatment of sudden hearing loss. The panel will discuss the newly developed AAO-HNS clinical practice guideline. The primary purpose of the guideline is to improve the diagnosis and management of sudden hearing loss in adults aged 18 years and older. In creating this guideline the AAO-HNSF selected a panel representing the fields of otolaryngology-head and neck surgery, audiology, otology, neurology, neurotology, family medicine, emergency medicine, and consumers.

Educational Objectives: 1) Learn diagnostic criteria for sudden sensorineural hearing loss. 2) Plan treatment based on current best evidence from randomized, controlled trials. 3) Identify management and counseling strategies that improve quality of care.

Clinical practice guideline: tonsillectomy in children

OBJECTIVE

Tonsillectomy is one of the most common surgical procedures in the United States, with more than 530,000 procedures performed annually in children younger than 15 years. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil including its capsule by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Depending on the context in which it is used, it may indicate tonsillectomy with adenoidectomy, especially in relation to sleep-disordered breathing. This guideline provides evidence-based recommendations on the preoperative, intraoperative, and postoperative care and management of children 1 to 18 years old under consideration for tonsillectomy. In addition, this guideline is intended for all clinicians in any setting who interact with children 1 to 18 years of age who may be candidates for tonsillectomy.

PURPOSE

The primary purpose of this guideline is to provide clinicians with evidence-based guidance in identifying children who are the best candidates for tonsillectomy. Secondary objectives are to optimize the perioperative management of children undergoing tonsillectomy, emphasize the need for evaluation and intervention in special populations, improve counseling and education of families of children who are considering tonsillectomy for their child, highlight the management options for patients with modifying factors, and reduce inappropriate or unnecessary variations in care.

RESULTS

The panel made a strong recommendation that clinicians should administer a single, intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. The panel made a strong recommendation against clinicians routinely administering or prescribing perioperative antibiotics to children undergoing tonsillectomy. The panel made recommendations for (1) watchful waiting for recurrent throat infection if there have been fewer than 7 episodes in the past year or fewer than 5 episodes per year in the past 2 years or fewer than 3 episodes per year in the past 3 years; (2) assessing the child with recurrent throat infection who does not meet criteria in statement 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergy/intolerance, periodic fever, aphthous stomatitis, pharyngitis and adenitis, or history of peritonsillar abscess; (3) asking caregivers of children with sleep-disordered breathing and tonsil hypertrophy about comorbid conditions that might improve after tonsillectomy, including growth retardation, poor school performance, enuresis, and behavioral problems; (4) counseling caregivers about tonsillectomy as a means to improve health in children with abnormal polysomnography who also have tonsil hypertrophy and sleep-disordered breathing; (5) counseling caregivers that sleep-disordered breathing may persist or recur after tonsillectomy and may require further management; (6) advocating for pain management after tonsillectomy and educating caregivers about the importance of managing and reassessing pain; and (7) clinicians who perform tonsillectomy should determine their rate of primary and secondary posttonsillectomy hemorrhage at least annually. The panel offered options to recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year or at least 5 episodes per year for 2 years or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and 1 or more of the following: temperature >38.3°C, cervical adenopathy, tonsillar exudate, or positive test for group A β-hemolytic streptococcus.

Extracts from The Cochrane Library: Antibiotics to reduce post-tonsillectomy morbidity

The “Cochrane Corner” is a quarterly section in the journal that highlights systematic reviews relevant to otolaryngology-head and neck surgery, with invited commentary to highlight implications for clinical decision making. This installment features a Cochrane Review entitled “Antibiotics to reduce post-tonsillectomy morbidity,” which concludes there is little or no evidence that antibiotics reduce pain or hemorrhage after tonsillectomy.

Management of frontal sinus fractures: a review of 96 cases

OBJECTIVES

The optimal treatment algorithm for frontal sinus fracture management remains ill-defined. The purpose of the study was to classify fracture types, review management methods, document associated injuries, and identify complications associated with various treatment options.

STUDY DESIGN

The authors conducted a retrospective chart review evaluating a 13-year experience with frontal sinus fracture management.

METHODS

Complete medical records of 96 frontal sinus fracture patients treated by the University of Kentucky Otolaryngology Service from 1990 to 2003 were reviewed.

RESULTS

The average patient age was 39 years. Fifty percent of the fractures involved the anterior table of the frontal sinus alone, and 50% involved both anterior and posterior tables. Forty-seven percent of the injuries were managed with observation, whereas 50% of patients underwent surgical repair. In the surgical group, 60% underwent open reduction and internal fixation (ORIF), 23% had a cranialization procedure, and 17% underwent sinus obliteration. The average length of follow up was 9 months. Complications occurred in 17% of the patients (5% in the nonsurgical group and 12% in the surgical group).

CONCLUSION

Our results support conservative management of nondisplaced or minimally displaced fractures based on the low complication rate seen in this series. Significant bone displacement can frequently be managed with simple ORIF. Complex fractures affecting the orbit or intracranial contents require cranialization or possibly obliteration. A subset of patients with suspected frontal sinus outflow obstruction can be considered for observation or simple ORIF with close follow up and endoscopic repair if outflow complications manifest.

Pharmacokinetics and Pharmacodynamics of a New Intranasal Midazolam Formulation in Healthy Volunteers

We evaluated the pharmacokinetics and pharmacodynamics of single 5-mg doses of midazolam after administration of a novel intranasal (IN) formula, IM, and IV midazolam in an open-label, randomized, 3-way cross-over study in 12 healthy volunteers. IN doses were delivered as 0.1-mL unit-dose sprays of a novel formulation into both naris. Blood samples were taken serially from 0 to 12 h after each dose. Plasma midazolam concentrations were determined by liquid chromatography/mass spectrometry/mass spectrometry. Noncompartmental analysis was used to estimate pharmacokinetic parameters. The mean midazolam bioavailabilities and % coefficient of variation were 72.5 (12) and 93.4 (12) after the IN and IM doses, respectively. Median time to maximum concentration was 10 min for IN doses. Adverse events were minimal with all routes of administration, but nasopharyngeal irritation, eyes watering, and a bad taste were reported after IN doses. Our results support further development of this novel midazolam nasal spray.

Bioavailability of intranasal butorphanol administered from a single-dose sprayer

PURPOSE

The bioavailability and tolerability of single doses of intranasal butorphanol tartrate using a single-dose, metered sprayer were studied.

METHODS

In this open-label, randomized, three-way crossover study, 24 healthy volunteers received three treatments: (1) 2 mg of i.v. butorphanol (treatment A), (2) 2 mg of intranasal butorphanol (treatment B), and (3) 1 mg of intranasal butorphanol (treatment C). The three treatments received by each subject were separated by six-day washout periods. Venous blood samples (10 mL each) were obtained from an indwelling catheter at 0 (predose), 5, 10, 15,20,30, and 45 minutes and 1,2,3,4,6,8, 12, and 16 hours after butorphanol administration. Pharmacokinetic parameters were determined using standard noncompartmental methods with log-linear least-squares regression analysis to determine the elimination-rate constants.

RESULTS

Intranasal butorphanol 1 and 2 mg administered using unit dose sprayers had a mean bioavailability of approximately 80%, which is higher than the percentage reported with the commercially available multidose product (61-69%). The absorption of intranasal butorphanol was rapid, with a median time to reach maximum concentration of 20 minutes (range, 10-60 minutes). Elimination profiles were comparable among all treatments. There were no clinically significant changes in the results of physical examinations, nasal evaluations, or laboratory tests related to butorphanol treatment. Most adverse effects reported were mild to moderate and as expected for this drug.

CONCLUSION

Single-dose intranasal butorphanol was rapidly absorbed and had high absolute bioavailability in healthy volunteers.

A Multiple-Dose Phase I Study of Intranasal Hydromorphone Hydrochloride in Healthy Volunteers

We evaluated the pharmacokinetics, tolerability, and safety of 1 and 2 mg of intranasal hydromorphone hydrochloride in an open-label, single- and multiple-dose study. This Phase I study was conducted in 24 healthy volunteers (13 men and 11 women). Intranasal doses were delivered as 0.1-mL metered-dose sprays into one or both nostrils for 1- and 2-mg doses, respectively. Venous blood samples were taken serially from 0 to 12 h after the first single dose and the last (seventh) multiple dose. Plasma hydromorphone concentrations were determined by liquid chromatography/mass spectrometry/mass spectrometry. Noncompartmental analysis was used to estimate pharmacokinetic variables. After 7 intranasal doses of 1 and 2 mg (once every 6 h), mean +/- sd peak plasma concentrations of 2.8 +/- 0.7 ng/mL and 5.3 +/- 2.3 ng/mL, respectively, were observed. The median time to peak concentration was 20 min for both single and multiple doses. Dose proportionality was observed for the 1- and 2-mg doses. Adverse events included somnolence, dizziness, and bad taste after dose administration. Intranasal hydromorphone hydrochloride was well tolerated and demonstrated rapid nasal drug absorption and predictable accumulation. These results support clinical investigation of hydromorphone hydrochloride nasal spray for use as an alternative to oral and IM administration.

Effect of fluticasone propionate nasal spray on bioavailability of intranasal hydromorphone hydrochloride in patients with allergic rhinitis

STUDY OBJECTIVE

To investigate the effect of the nasal corticosteroid fluticasone propionate on the bioavailability and pharmacokinetics of single-dose intranasal hydromorphone hydrochloride in patients with allergic rhinitis.

DESIGN

Randomized, three-way, crossover pharmacokinetic study.

SETTING

University clinical research unit.

PATIENTS

Twelve patients with allergic rhinitis.

INTERVENTION

Hydromorphone hydrochloride 2.0 mg was administered by intravenous infusion (treatment A), intranasal spray without allergic rhinitis treatment (treatment B), and intranasal spray after 6 days of fluticasone propionate (treatment C). Blood samples were collected serially from 0-16 hours.

MEASUREMENTS AND MAIN RESULTS

Pharmacokinetic parameters were determined by noncompartmental methods. An analysis of variance (ANOVA) model was used for statistical analysis. Mean (% coefficient of variation) absolute bioavailability of intranasal hydromorphone was 51.9% (28.2) and 46.9% (30.3) in patients with allergic rhinitis with and without treatment with fluticasone propionate, respectively. Mean maximum concentration (Cmax) values were 3.02 and 3.56 ng/ml, respectively. No statistical differences in Cmax and area under the concentration versus time curve were detected between intranasal treatments. Bioavailability values for both intranasal treatments were lower than those in healthy volunteers (57%). Median time to Cmax (Tmax) values were significantly different (p=0.02) for treatments B and C (15 and 30 min, respectively) using rank-transformed Tmax for ANOVA. Adverse effects were consistent with known effects of hydromorphone administered by other routes, with the exception of bad taste after intranasal administration.

CONCLUSION

Hydromorphone was rapidly absorbed after nasal administration, with maximum concentrations occurring for most subjects within 30 minutes. Allergic rhinitis may affect pain management strategies for intranasal hydromorphone, with a delay in onset of action for patients treated with fluticasone propionate.

Pharmacokinetics of butorphanol tartrate administered from single-dose intranasal sprayer

PURPOSE

The pharmacokinetics and tolerability of single and multiple doses of intranasal butorphanol tartrate using a single-dose metered sprayer were studied.

METHODS

In this randomized, open-label, two-way crossover study, 24 healthy subjects received either 1 or 2 mg of intranasal butorphanol as a single dose (treatment A) and 1 or 2 mg of intranasal butorphanol every six hours for seven doses (treatment B). During phase 1, 12 subjects selected at random received a single 1-mg dose and the other 12 a single 2-mg dose. During phase 2, those who received the 1-mg single dose received 1 mg every six hours for seven doses. During phase 3, those who received the 2-mg single dose received 2 mg every six hours for seven doses. Serial blood samples were collected over 12 hours. Pharmacokinetic parameters were determined using noncompartmental methods.

RESULTS

Mean (coefficient of variation) values for the area under the concentration-versus-time curve (AUC) from time zero to infinity (AUC0-infinity) were 4.15 (26.4%) and 10.42 (19.6%) ng.hr/ml after single doses of 1 and 2 mg of butorphanol, respectively. At steadly state, mean values for the AUC from time zero to the dosing interval (AUC0-tau) were 4.82 (40.2%) and 10.60 (22.3%) ng.hr/mL, respectively. The accumulation indices were around 2 for both the 1- and 2-mg doses. Median time to maximum concentration values ranged from 15 to 30 minutes for each treatment. Dose-normalized parameters AUC0-infinity. AUC0-tau and maximum concentration (Cmax) were significantly larger after a single 2-mg versus 1-mg dose (p < 0.05).

CONCLUSION

Intranasal butorphanol has rapid absorption and predictable accumulation after multiple doses administered with single-dose metered sprayers. Intranasal administration of butorphanol was well tolerated and adverse events were generally mild to moderate in severity and as expected for this drug.

Bioavailability and Pharmacokinetics of Intranasal Hydromorphone in???Patients Experiencing Vasomotor Rhinitis

BACKGROUND AND OBJECTIVE

Narcotic analgesics such as hydromorphone undergo an extensive first-pass effect resulting in a low systemic bioavailability following oral administration. Alternative dosing routes, such as rectal and intranasal (IN) routes, have been suggested as options for oral or intravenous administration. Rhinitis and pharmacological agents used for treatment are considered factors that could alter the rate and extent of absorption of drugs administered by the nasal route. The purpose of this study was to evaluate the pharmacokinetics of intranasal hydromorphone hydrochloride (HCl) in patients with vasomotor rhinitis.

METHODS

Ten patients completed the randomised, three-way crossover study. During the three treatment periods, a single dose of hydromorphone HCl 2.0mg was administered via intravenous infusion (treatment A) and the intranasal route without (treatment B) or with (treatment C) vasoconstrictor pretreatment for rhinitis. Blood samples were collected serially from 0 to 16 hours. Noncompartmental methods were used to determine pharmacokinetic parameters.

RESULTS

Maximum plasma concentrations were 3.69 and 3.38 mug/L for treatments B and C, respectively. Mean (% coefficient of variation) bioavailability of intranasal hydromorphone was 54.4% (34.8) and 59.8% (22.1) with and without pretreatment, respectively. Pretreatment of rhinitis did not significantly affect the rate or extent of absorption of hydromorphone in this study. There was not a significant difference in bioavailability between treated and untreated rhinitis.

CONCLUSIONS

This study found intranasal administration of hydromorphone in patients experiencing vasomotor rhinitis had acceptable bioavailability and a pharmacokinetic profile comparable to previous studies. These data support further investigation of this single-dose delivery system for clinical use.

Pharmacokinetics and bioavailability of single-dose intranasal hydromorphone hydrochloride in healthy volunteers

We evaluated pharmacokinetics and absolute bioavailability of single doses of hydromorphone hydrochloride after administration of 1.0 and 2.0 mg of intranasal (IN) and 2.0 mg of IV hydromorphone hydrochloride. An open-label, randomized, three-way crossover study was conducted in 24 healthy volunteers (13 men and 11 women). IN doses were delivered as 0.1-mL metered-dose sprays into one or both nostrils for 1.0- and 2.0-mg doses, respectively. Blood samples were taken serially from 0 to 16 h after each dose. Plasma hydromorphone concentrations were determined by liquid chromatography-mass spectrometry-mass spectrometry. Noncompartmental analysis was used to estimate pharmacokinetic variables. Mean hydromorphone bioavailabilities and percent coefficient of variation of 52.4% (22.7) and 57.5% (18.6) were seen after the 1.0- and 2.0-mg IN doses, respectively. Median times to maximum concentration were 20 and 25 min for IN doses. Adverse events included somnolence and dizziness with all routes of administration and a bad taste after IN doses. Dose proportionality for the 1.0- and 2.0-mg IN doses was observed. IN hydromorphone hydrochloride met the minimum requirements for safety and demonstrated rapid nasal drug absorption and clinically relevant bioavailability. Results support further development of this novel hydromorphone hydrochloride nasal spray.

IMPLICATIONS

Pharmacokinetics and bioavailability were determined for two doses of intranasal hydromorphone in healthy volunteers. Rapid, reliable absorption, and predictable pharmacokinetics support the investigation of hydromorphone hydrochloride nasal spray as a therapeutic alternative to oral and IM administration.

Bioavailability and pharmacokinetics of lorazepam after intranasal, intravenous, and intramuscular administration

The purpose of this study was to evaluate the pharmacokinetic profile of intranasal lorazepam in comparison to currently established administration routes. Eleven healthy volunteers completed this randomized crossover study. On three occasions, each separated by a 1-week washout, subjects received a 2 mg dose of lorazepam via the intranasal, intravenous, or intramuscular route. Blood samples were collected serially from 0 to 36 hours. Noncompartmental methods were used to determine pharmacokinetic parameters. Lorazepam was well absorbed following intranasal administration with a mean (%CV) bioavailability of 77.7(11.1). Intranasal administration resulted in a faster absorption rate than intramuscular administration. Elimination profiles were comparable between all three routes. The concentration-time profile for intranasal delivery demonstrated evidence of a double peak in several subjects, suggesting partial oral absorption. Females were found to have significantly higher AUC values than males for all three delivery routes. Overall, this study demonstrated favorable pharmacokinetics of intranasal lorazepam in relation to standard administration methods. Intranasal delivery could provide an alternative, noninvasive delivery route for lorazepam.

Renal Clear Cell Carcinoma Appearing as a Left Neck Mass

Malignant clear cell tumors of the head and neck are uncommon. Primary tumors may arise from the salivary glands, thyroid gland, or parathyroid glands, while metastatic tumors most commonly arise from the lungs, kidneys, and female genital tract.

Renal cell carcinoma is the third most common metastatic tumor to the bone and soft tissues of the head and neck. Despite this, there have been few reported cases of renal clear cell carcinoma metastases to the neck. Here we report a unique case of an otherwise asymptomatic young woman with a left neck mass as the first clinical sign of advanced renal clear cell carcinoma.

Renal clear cell carcinoma appearing as a left neck mass

Malignant clear cell tumors of the head and neck are uncommon. Primary tumors may arise from the salivary glands, thyroid gland, or parathyroid glands, while metastatic tumors most commonly arise from the lungs, kidneys, and female genital tract. Renal cell carcinoma is the third most common metastatic tumor to the bone and soft tissues of the head and neck. Despite this, there have been few reported cases of renal clear cell carcinoma metastases to the neck. Here we report a unique case of an otherwise asymptomatic young woman with a left neck mass as the first clinical sign of advanced renal clear cell carcinoma.

Fat adherence syndrome treated with intraoperative mitomycin-C: a rabbit model

We used an animal model of restrictive strabismus analogous to the fat adherence syndrome in humans to test the efficacy of topical intraoperative mitomycin-C (MMC) in preventing the development of restrictive scar tissue. A cicatricial adhesion was created between the inferior rectus muscle and the inferior orbital rim of each eye in eight rabbits, and passive forced ductions were quantitatively measured with a spring scale. Eight eyes were treated intraoperatively with topical MMC 0.5 mg/mL, the other eight with sterile water. Passive forced ductions were again measured 4 weeks postoperatively and representative orbits were exenterated for histopathologic examination. Significant restriction of motility was produced in six of the eight control eyes. Though prophylactic treatment with MMC may have been beneficial in some cases, on average, the restriction developing in these eyes did not significantly differ from that in the control eyes. In addition, longer exposure times to MMC led to marked orbital inflammation and severe restriction of ocular motility. Finally, histopathologic evaluation of the orbits of the MMC-treated eyes revealed marked fibrosis of perimuscular connective tissues. Although MMC may have a role in the management of fat adherence syndrome, further study is needed to establish safe and efficacious methods of delivery.

Surgery for obstructive sleep apnea: effects on sleep, breathing, and oxygenation

Advances in the treatment of obstructive sleep apnea have evolved rapidly over the past two decades. Nasal continuous positive airway pressure (CPAP) devices are effective, but are neither curative nor universally well tolerated. Uvulopalatopharyngoplasty (UPPP) has been reported to have widely varying success rates; many studies of this procedure do not include data about sleep quality, oxygenation, or patient satisfaction. The role of nasal surgery in the treatment of obstructive sleep apnea in the hands of a single surgeon, specifically evaluating its effects on sleep and oxygenation parameters. Overall, 12 of 15 patients (80%) had marked improvement, reflected by oximetry and patient interview. This pilot study shows that the combined use of UPPP and nasal surgery, when indicated, for obstructive sleep apnea is an acceptable alternative in nasal CPAP-intolerant patients. Further studies with larger numbers are needed to further substantiate these findings.

Vertical shift of the medial rectus muscles in the treatment of A-pattern esotropia: analysis of outcome

A retrospective study was performed on 18 consecutive patients with A-pattern esotropia and no apparent oblique muscle dysfunction, mechanical restriction, paresis, or previous muscle surgery. All patients underwent graded bilateral medial rectus recession for their esotropia with simultaneous vertical upshift to treat the A-pattern. The quantitative relationship between amount of upshift, amount of A-pattern correction, preoperative A-pattern, and preoperative esotropia was examined. We found that the amount of A-pattern correction was closely correlated with the size of the A-pattern preoperatively (r = 0.83), independent of amount of upshift. While the change in A-pattern did correlate with the amount of the upshift (r = 0.60), it was not a significant independent predictor of the surgical response. The amount of recession had little influence on the effectiveness of the procedure in correcting the vertical incomitance, and the transposition did not seem to affect the correction of the basic esotropia, adversely. We conclude that medial rectus recession with vertical upshift of the muscle insertions is an effective procedure for correcting the vertical incomitance in A-pattern esotropia, and that the amount of A-pattern correction achieved is determined primarily by the size of the preoperative A-pattern and not the amount of upshift.

Prophylactic antibiotic drops after tympanostomy tube placement

OBJECTIVE

To evaluate the effectiveness of prophylactic polymyxin B sulfate-neomycin sulfate-hydrocortisone drops in decreasing the incidence of posttympanostomy otorrhea.

DESIGN

Prospective randomized controlled study.

SETTING

University referral center.

PATIENTS

Three hundred patients undergoing tympanostomy tube placement (including those undergoing tonsillectomy, adenoidectomy, or both) were randomized into three groups.

INTERVENTION

The use of polymyxin B-neomycin-hydrocortisone drops. Patients in group 1 received no antibiotic drops; group 2, a single dose intraoperatively, and group 3, an intraoperative dose followed by a 5-day course.

MAIN OUTCOME MEASURE

Posttympanostomy otorrhea.

RESULTS

A statistically significant decrease was observed in the incidence of posttympanostomy otorrhea between the control (16.4%) and treatment groups (group 2, 8.3%; group 3, 8.1%) (P = .011). A single dose of antibiotics was effective when patients' middle ears were dry or had serous effusions. A 5-day course was indicated for those whose ears had mucoid or purulent contents.

CONCLUSIONS

Antibiotic ear drops are indicated in all patients. A single dose is as effective as a 5-day course, but our data support a longer course in certain subgroups.

Vernier acuity cards: a practical method for measuring vernier acuity in infants

The feasibility of a practical preferential looking technique, similar to Teller acuity cards, was investigated for the assessment of vernier acuity in preverbal infants. Forty-two infants ages 1 to 13 months were tested with cards having vernier offsets of 2 to 64 minutes of arc and spatial frequencies of 0.25 to 2.0 cycles per degree. All infants showed a robust preferential looking response to the largest vernier offsets. Vernier thresholds decreased with age from 64 minutes of arc at 1 month to 4 minutes of arc at 13 months. Smaller vernier offsets were more readily detectable when embedded in higher spatial frequency gratings. Vernier acuity can be assessed in preverbal infants using a preferential looking technique similar to that employed with the Teller acuity cards. Vernier acuity is known to be more sensitive to amblyopia than grating acuity; therefore, this technique may prove useful in the assessment of amblyopia.

Children with exotropia responsive to spectacle correction of hyperopia

A series of seven exotropic children (aged 2 to 10 years) had resolution of exotropia after spectacle correction of hyperopia. Their hyperopic correction ranged from 3.00 to 7.00 diopters. Six had intermittent exotropia, which became small-angle esophoria after spectacle correction. In one patient with apparently no fusion, spectacle correction converted constant exotropia to small esotropia in the monofixational range. In all patients, Worth 4-dot and Titmus Stereo Test results, when obtainable, indicated an improvement in binocular sensory status after correction of the hyperopia. We conclude that a trial of spectacle correction is warranted in exotropic children with severe hyperopia and in those with moderate hyperopia and a low accommodative convergence/accommodation ratio or evidence of hypoaccommodation.

Acquired flaccid larynx. A case report supporting the neurologic theory of laryngomalacia

Congenital flaccid larynx, also known as laryngomalacia, is a common clinical entity accounting for approximately 60% of laryngeal problems in the newborn. It is a benign and relatively asymptomatic condition that patients often outgrow by 12 to 18 months of age. A variety of mechanisms have been proposed to explain laryngomalacia including cartilage immaturity and poor neuromuscular control secondary to hypomaturity or dysfunction. This entity has only recently been described as an acquired disorder. A case of an 11-year-old boy who presented with basilar artery thrombosis and a midpontine infarction is described. Inability to extubate despite spontaneous respirations prompted flexible laryngoscopy, which revealed complete supraglottic collapse with airway obstruction. The patient was successfully treated with an epiglottoplasty. This case supports the neuromuscular dysfunction theory as a cause of laryngomalacia.

Measurement of low vision in children and infants

The authors evaluated a preferential looking technique (Teller acuity cards) and a set of gross behavioral indicators (visual function battery) for the ability to rank visually impaired children and infants on the basis of their visual function. Fourteen older children with a diagnosis of cicatricial retinopathy of prematurity who were capable of giving Snellen acuities and a group of 31 preverbal infants with decreased vision due to a variety of causes were tested. Teller acuity card and visual function battery findings were highly correlated with each other (and with Snellen acuities in the older group); however, the Teller acuity cards provided better discrimination in the moderately visually impaired range, whereas the visual function battery was better in the severely impaired range. It is concluded that, in children and infants, visual function over the entire spectrum of low vision can be characterized by using a combination of the Teller acuity cards and the visual function battery.

Strabismus in infancy

In order to prospectively study the development of strabismus in infancy, the ocular alignment of a large population of normal neonates was studied and follow-up examinations were obtained in a subset of these infants. The characteristic findings of congenital esotropia subsequently developed in three infants who were either orthotropic or exotropic at birth. Pathologic exotropia developed in two infants; both were exotropic at birth, but no more so than most normal neonates. In infants with congenital esotropia or pathologic exotropia, the characteristic deviation appears to develop between 2 and 4 months of age, a period during which normal infants are becoming increasingly orthotropic.

Hamartoma of the larynx: report of two cases and review of the literature

Hamartomas of the larynx are rare. Signs and symptoms vary but there is generally some degree of voice change and upper airway obstruction. The pathology may be misleading and can often be confused with other benign tumors of the larynx. Management should consist of conservative excision. Partial or total laryngectomy should be reserved for lesions involving too much of the laryngeal framework. Two cases of hamartomas of the larynx are reported requiring partial laryngectomy.

Development of normal ocular alignment

Ocular alignment was examined in a large population of normal infants to determine the prevalence of various motility findings at ages ranging from birth to 10 months. Exodeviations were frequently seen up to the age of 6 months. Esodeviations were occasionally seen in infants who did not go on to develop congenital esotropia, but not after 2 months of age. It is unclear whether precursors of pathologic strabismus, such as congenital esotropia, can be distinguished from these transient ocular deviations seen in normal infants. However, any strabismus persisting after the ages listed above should be considered abnormal and receive ophthalmologic evaluation.

Developmental aspects of the Brückner test

Normal infants ranging from newborn to 10 months of age were examined in order to study age-related variation in the behavior of the fundus reflexes seen in the course of performing the Brückner test. Most infants 8 months of age and older show the characteristic symmetric dimming of the fundus reflexes in both eyes occurring with central fixation. Neonates and most infants younger than 2 months of age do not show dimming of the fundus reflex with fixation, probably due to an inability to accommodate accurately. Between 2 and 8 months of age, up to 28% of infants have asymmetric dimming of the fundus reflexes in the two eyes. In contrast to older children in which this is a pathologic finding, asymmetric fundus reflexes occurring in this age range may represent a normal stage of development.

Stereotest artifacts and the strabismus patient

A new use of nonstereoscopic cues in stereopsis testing is described. It consists of alternation of fixation while observing for image jump in the disparate portions of the test target. This may enable some stereoblind strabismus patients to achieve artifactually good stereotest scores and explain those patients who appear to have gross stereopsis on the Titmus test, but are unable to perform any random-dot test of stereopsis. A new stereotest is described which does not resort to a random-dot format and yet is free from lateral displacement and alternation cues.

The effect of intravitreal botulinum toxin on rabbit visual evoked potential

Intravitreal injections of botulinum A toxin in two doses, 1.25 and 25 units, were performed in two rabbit eyes. The fellow eyes were injected with an equal volume of saline to serve as controls. The visual evoked potential was unchanged at one and two weeks post-injection when compared to pre-injection recordings in both botulinum and saline injected eyes.

Stereoscopic contours and optokinetic nystagmus in normal and stereoblind subjects

Moving stereoscopic contours in a dynamic random-dot stereogram have been previously shown to induce optokinetic nystagmus in subjects with normal stereopsis. For this to be validated as an objective test of stereopsis, stereoblind subjects must also be shown not to develop OKN, especially since it has been shown that the optomotor system of stereoblind individuals retains sensitivity to some cyclopean stimuli. In this report we verify that stereoblind subjects do not have an optomotor response to stereoscopic contours--regardless of the alignment angle at which the stereo image pair is presented.

Vergence amplitudes with random-dot stereograms

Random-dot stereograms were found to be capable of producing fusional vergence amplitudes in the absence of monocular contours. These vergence amplitudes are not an artefact of monocular contours provided by the target borders or test instrument and are comparable in range to vergence amplitudes measured clinically with second degree fusion targets in an amblyoscope. We conclude that diplopia of monocularly recognisable contours is not necessary for producing fusional vergence amplitudes.

Sera of patients with cancer or cirrhosis and of newborns exhibiting inhibitory effects on the metabolism of cortisol by lymphocytes

The effect was examined of ethanol extracts of normal sera (NS), cancer patients' sera (CPS), cirrhosis patients' sera (CirPS), and umbilical cord sera (UCS) on cortisol metabolism by lymphocytes (CML). All the ethanol extracts of these sera showed an inhibitory effect on CML. The most significant inhibition was obtained with CPS and CirPS followed by UCS. A significant inhibition of NS was obtained after doubling their equivalent volume.

Stereopsis in normal infants and infants with congenital esotropia

We used electro-oculographic recordings of eye movement responses to a dynamic random-dot stereogram to assess stereopsis in normal infants and in infants with congenital esotropia. Normal infants showed an onset of stereopsis at about 4 months of age, consistent with previous reports. Four of nine infants with congenital esotropia demonstrated stereopsis when tested within two weeks of surgical alignment. No patient with congenital esotropia showed evidence of stereopsis when tested at a postoperative interval of more than two weeks.

A role for action-potential activity in the development of neuronal connections in the kitten retinogeniculate pathway

The role of action potentials in the development of proper synaptic connections in the mammalian CNS was studied in the kitten retinogeniculate pathway. Our basic finding is that there is improper segregation of retinal inputs onto LGN cells after prolonged retinal action-potential blockade. Retinal ganglion cell firing was silenced from birth by repeated monocular injections of TTX. The resulting ganglion cell connections in the LGN were studied electrophysiologically after the action-potential blockade was ended. Most cells in the deprived LGN layers received excitatory input from both ON-center and OFF-center type ganglion cells, whereas LGN cells normally receive inputs only from ON-center or OFF-center ganglion cells, but not from both types. Improper segregation of ON and OFF inputs has never been reported after other types of visual deprivation that do not block ganglion cell activity. Control experiments showed that receptive fields in the nondeprived LGN layers were normal, that ganglion cell responses remained normal, and that there was no obvious ganglion cell loss. We also showed that individual LGN cells with ON and OFF excitatory inputs were not present in normal neonatal kittens. Two other types of improper input segregation in response to action-potential blockade were also found in the deprived LGN layers. (1) A greater than normal number of LGN cells received both X- and Y-type ganglion cell input. (2) Almost half of the cells at LGN layer borders were excited binocularly. Recovery of LGN normality was rapid and complete after blockade that lasted for only 3 weeks from birth, but little recovery was seen after about 11 weeks of blockade. The susceptibility to action-potential blockade decreased during the first 3 postnatal weeks. These findings may result from axon-terminal sprouting or from the failure of axon terminals to retract. The results are consistent with the idea that normally synchronous activity of neighboring ganglion cells of like center-type may be used in the refinement of retinogeniculate synaptic connections.

Incidence of strabismus in neonates

In an attempt to learn whether esotropia is present at birth or develops later in infancy, we observed 1,219 alert infants in a normal newborn nursery at a city hospital. Of these, 593 (48.6%) had orthotropic findings; 398 (32.7%) had exotropia, 40 (3.2%) had esotropia (intermittent in 17 with 14 varying between esotropia and exotropia and nine with a variable esotropia), and 188 (15.4%) were not sufficiently alert to permit classification. No infant displayed typical signs of congenital esotropia. We concluded that congenital-infantile esotropia is not connatal but rather develops in the first few weeks or months after birth.