Search PubMedSearch

Biomedical subjects

B E Hirsch

Publications and source records attributed to B E Hirsch.

At least 19 recordsLinked to original sources

Magnetic resonance imaging of the large vestibular aqueduct.

The large vestibular aqueduct syndrome describes an abnormally large endolymphatic duct and sac with associated sensorineural hearing loss. This entity was originally reported in 1978 and has since been identified as a finding in children with progressive hearing loss. The original description of the large vestibular aqueduct employed hypocycloidal polytomography of temporal bone. Subsequent reports studied patients identified with this syndrome using computed tomographic scans. We report magnetic resonance imaging of two patients diagnosed with the large vestibular aqueduct syndrome. The magnetic resonance imaging and computed tomographic scans are compared and the significant findings on magnetic resonance imaging are reviewed. This should assist the otolaryngologist and radiologist with establishing the appropriate diagnosis.

Adult

Single-stage management of cholesteatoma.

Surgical management of chronic otitis media with cholesteatoma can be performed in a single-stage procedure, with revision surgery necessary because of recurrent disease or electively with unsatisfactory hearing results. We retrospectively reviewed 164 cases with cholesteatoma surgically managed from 1980 through 1986. In total there were 11 tympanoplasties, 36 canal wall-up mastoidectomies, 81 canal wall down modified radical mastoidectomies, and 36 radical mastoidectomies. The recidivistic rate for cholesteatoma in patients available for 5-year followup was 11% for tympanoplasties, 19% for canal wall-up mastoidectomies, 5% for canal wall-down modified radical mastoidectomies, and 0% for radical mastoidectomies. Hearing results were best in patients who required tympanoplasty alone, followed by those who underwent canal wall-down procedures. Single-stage management of cholesteatoma with modified radical mastoidectomy (canal wall-down) required fewer revisions for recidivistic cholesteatoma and achieved better hearing results than canal wall-up procedures. We conclude, therefore, that staging is not necessary. Improved hearing may likely be achieved with a second procedure, but this is at the patient's discretion.

Adolescent

Hyperbaric oxygen therapy: effect on middle ear and eustachian tube function.

Hyperbaric oxygen therapy (HBO) involves intermittent inhalation of 100% oxygen under a pressure greater than 1 atm. It is an important mode of adjuvant therapy for disease processes such as decompression sickness, osteomyelitis, carbon monoxide poisoning, and poorly healing wounds. Patients undergoing this therapy often complain of ear pain and/or fullness which can be transient or long standing. This prospective study objectively measured the changes in eustachian tube function before and after HBO treatment in 33 adult patients by the 9-step inflation-deflation test described by Bluestone. The results show 15 of the 33 patients (45%) had evidence of eustachian tube dysfunction after treatment was initiated. Of these, 15 (100%) developed the sensation of fullness, 13 (87%) developed serous otitis media, and 7 (47%) required tympanostomy tubes. The overall incidence of middle ear problems was 27 patients (82%) experiencing a sensation of fullness, 17 (52%) developing serous otitis media, and 8 (24%) requiring tympanostomy tubes. The middle ear complications reported in this study are much higher than those in previous reports in the literature. Twelve of 33 patients presented with a subjective history of eustachian tube dysfunction, and all 12 (100%) developed fullness in their ears and serous otitis media during the course of the treatment. The findings reveal that patients manifesting eustachian tube dysfunction after their first HBO treatment were at significantly greater risk toward developing symptoms of fullness and serous otitis media, often requiring tympanostomy tube placement. In addition, a history of eustachian tube dysfunction accurately predicted the development of fullness and serous otitis media.

Acoustic Impedance Tests

Beta 2 transferrin application in otology.

The diagnosis and management of perilymphatic fistula has received considerable attention in recent years. Despite the use of sophisticated technology, the diagnosis of perilymphatic fistula continues to rest primarily upon clinical suspicion and the exclusion of other disorders. In addition, the confirmation of a perilymphatic fistula during surgical exploration is usually based upon the subjective observation of fluid pooling in niches of the middle ear. A sensitive and objective laboratory test for identifying perilymph in the middle ear would be a useful adjunct for the diagnosis and management of perilymphatic fistula. The objective of this paper is to demonstrate the potential utility of beta 2 (beta 2) transferrin assay in the diagnosis of perilymphatic fistula. To accomplish this objective, we confirmed that beta 2 transferrin is present in living human perilymph and is absent in the normal or inflamed middle ear. In addition, the utility of beta 2 transferrin assay in the diagnosis of cerebrospinal fluid otorrhea is presented.

Aged

Bell's palsy. A diagnosis of exclusion.

In cases of acute unilateral facial weakness, a careful and systematic evaluation is necessary to identify the cause. Idiopathic facial paralysis (Bell's palsy) is a diagnosis of exclusion. It is also the most common cause of unilateral facial weakness seen by primary care physicians. The most important aspect of initial treatment is eye protection. Administration of systemic oral corticosteroids may lessen severity and duration of symptoms.

Adrenal Cortex Hormones

Instillation of vancomycin into a cerebrospinal fluid reservoir to clear infection: pharmacokinetic considerations.

Vancomycin instilled in an Ommaya reservoir was used to treat a reservoir-associated infection. Vancomycin concentrations in cerebrospinal fluid (CSF) were measured, and derivation of pharmacokinetic parameters allowed tailoring of dosing. First-order kinetics were observed. The calculated half-life of 3.52 h was less than reported by others, and the apparent volume of distribution (60 ml) was less than anticipated. The elimination constant was 0.197 h-1. Empiric dosing based on schedules suggested in the literature would have led to high peak and low mean concentrations of intrareservoir vancomycin. Patients with reservoir-associated infections have a variety of pathophysiologic conditions that can result in alteration of normal CSF dynamics. Pharmacokinetic analysis is useful to individualize dosing and to optimize therapy with intrareservoir vancomycin.

Adult

Abscess of the sphenoid sinus after transsphenoidal surgery.

A case of a bacterial abscess developing in the sphenoid sinus 2 weeks after transsphenoidal surgery is presented. Although abscesses within the sella turcica have been reported as rare complications of transsphenoidal surgery, this is the first reported case of the postoperative formation of an abscess of the sphenoid sinus. The patient sought treatment for severe headaches, nausea and vomiting, and marked temperature elevation. A computed tomographic scan demonstrated soft tissue and air within the sphenoid sinus. A regimen of stress doses of hydrocortisone and antibiotics was prescribed, and the patient underwent transsphenoidal drainage of the sphenoid sinus. The sella turcica was not involved. Anaerobic cultures were positive for Fusobacterium necrophorum.

Abscess

Dehiscent temporomandibular joint.

The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion.

Adolescent

Structural biomechanics of the foot bones.

The structure of the tarsal and metatarsal bones reflects the functional demands placed on them. Their shape and the arrangement of compact and trabecular bone within them help them resist the normal forces of everyday life. When the limits of their strength are exceeded, failure can occur.

Biomechanical Phenomena

Metastatic atrial myxoma to the temporal bone: case report.

A 25-year-old male underwent right mastoid surgery for removal of a soft tissue mass. At age 29 a left cardiac atrial myxoma was excised. At age 34 an expanding right supra-auricular mass with extension into the middle and posterior fossa necessitated total temporal bone resection. Pathology proved to be myxoma. Retrospective review of tissue obtained from the initial mastoid procedure was also myxoma. The temporal bone lesion was considered to be persistent and metastatic atrial myxoma. A review of atrial myxomas and this most unusual metastatic presentation is discussed.

Adult

Staging proposal for external auditory meatus carcinoma based on preoperative clinical examination and computed tomography findings.

An accepted staging system for squamous cell carcinoma of the external auditory meatus is currently lacking and would permit accurate comparison of treatment strategies and results for patients with this unusual neoplasm. In order to develop such a staging system we reviewed the prognostic variables and the accuracy of radiographic diagnosis in 39 patients undergoing temporal bone resection for squamous carcinoma of the external auditory meatus. Predictors of poor survival were extensive tumor involvement, facial nerve paralysis, middle ear involvement, and cervical or periparotid lymphadenopathy. In a comparison of 12 specific anatomic sites, computed tomography was found to be an accurate indicator of histopathologically proven tumor invasion. On the basis of this clinical radiographic-histopathologic analysis, we propose a TNM staging system for external auditory meatus carcinoma utilizing preoperative computed tomography and physical examination. This system fulfills the requirements of the American Joint Committee on Cancer that a staging system should provide a sound basis for therapeutic planning for cancer patients by describing the survival and resultant treatment of different patient groups in comparable form.

Aged

Posterior nasal packing. Are intravenous antibiotics really necessary?

The use of antimicrobial prophylaxis in the presence of posterior nasal packing for the treatment of posterior epistaxis remains controversial. Twenty patients were prospectively randomized into this placebo-controlled, double-masked pilot study to receive either placebo or cefazolin sodium. Antibiotic-impregnated posterior gauze packing was employed in all patients. No infectious complications were noted in either group. The packings from the patients in the placebo group were foul smelling and heavily colonized with gram-negative bacteria while the packings from the antibiotic group were odor-free and lightly colonized with gram-positive organisms. This preliminary study suggests the usefulness of antimicrobial prophylaxis for preventing complications from posterior nasal packing, although a larger sample size will be needed to decrease the type II (beta) error.

Adult

Cardiac myxoma metastatic to the temporal bone.

Two metastases from an atrial myxoma occurred in the right common carotid artery distribution of a 34-year-old man. One metastasis caused the phenomenon of intracranial pseudoaneurysm in a distal branch of the middle cerebral artery. The other resulted in the unusual radiographic appearance of a tremendous, "bubbly" expansion of the temporal bone.

Adult

Squamous cell carcinoma of the external auditory meatus (canal).

A retrospective study of 35 patients with squamous cell carcinoma of the external auditory meatus treated at the Eye and Ear Hospital of the University of Pittsburgh was performed. The standard treatment was a temporal bone resection that corresponded to the extent of the lesion, followed by postoperative radiation therapy. The tumor extensions, symptoms, treatments, survival rates, and prognostic variables were reviewed. Overall, 12 of 35 patients survived. Lesions limited to the external auditory meatus with no erosion had excellent prognoses. Survival in intermediate lesions with bony erosion or middle ear involvement was related to the status of surgical margins after partial or subtotal temporal bone resections. Extensive lesions that involved the surrounding soft tissue or dura had poor prognoses. The survival value of total temporal bone resection remains unproved.

Aged

Three-dimensional reconstruction of the foot from computed tomography scans.

Recently developed computer programs create a new type of image from the sections created in computed tomography. These images look like actual photographs of internal structures. The authors describe the process of three-dimensional reconstruction in nonmathematical terms, and provide examples of its use in imaging the bones of the foot. They demonstrate the technique's ability to resolve small details, and its usefulness in displaying articular surfaces.

Computer Graphics