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Biomedical subjects

D G Pappas

Publications and source records attributed to D G Pappas.

At least 37 records · Page 2Linked to original sources
PubMed1995

Ultrastructural findings in the vestibular end-organs of AIDS cases.

Neurotologic manifestations are apparent in human immunodeficiency virus (HIV) infection, but are poorly understood. Symptoms related to the vestibular system include episodes of vertigo, imbalance, ataxia, and nausea. Although patients present more often with hearing impairment, vestibular complaints are described and electrophysiologic studies indicate vestibular dysfunction in HIV-infected patients. Whether the disease involvement includes the central, or the peripheral nervous system has not been established. Ultrastructural analysis of vestibular end-organs obtained from HIV autopsy cases revealed pathologic changes in the labyrinth wall, the epithelial lining, and the receptor maculae and cristae. Cytologic changes in hair cells included inclusion bodies, viral-like particles, and hair bundle malformations. Epithelial lining cells, supporting cells, and connective tissue cells had inclusions and viral-like particles. These findings are consistent with those of a previous cochlear study demonstrating intracellular viral-like particles with the morphologic characteristics of HIV. Further cytologic evaluation of decalcified temporal bones and immunohistochemical analysis of freshly harvested HIV-infected temporal bones may provide further insight into the pathogenesis of viral-induced hearing loss and vestibular impairment.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Otological and habilitative management of children with Down syndrome.

It has been well-established that children with Down syndrome experience a high incidence of persistent conductive hearing loss because of their predisposition to stenosis of the external auditory canal (EAC), cerumen impaction, serous otitis media (SOM), and cholesteatoma. Because this hearing problem may be a primary cause of the spoken communication skills in these children being far below their cognitive ability, assertive management is required. The authors present an aggressive multi-discipline treatment model that is instituted during the first year of life in an infant with Down syndrome. Reconstruction of the EAC, amplification technology, and speech/language intervention that emphasizes auditory-verbal (A/V) therapy are discussed. In a pilot study, we compared the language development of six infants with Down syndrome who received aggressive treatment during their first year of life (group A) to six infants who did not (group B). The results showed age-appropriate oral language development for the infants in group A.

Child Development↗
PubMed1994

Bondy's modified radical mastoidectomy revisited.

The original criteria for modifying a radical mastoidectomy were: (1) an intact pars tensa and a defective pars flaccida with cholesteatoma; (2) normal or near normal hearing; and (3) an intact, functional ossicular chain. We propose a fourth criterion: that the cholesteatoma site be delineated lateral to the body of the incus. Control of the disease process is easily assured if the lesion is in that area. Our recommended fourth criterion is based on the results of a five-year study of fifty-two cases that met the original criteria. The cholesteatoma reoccurred in the middle ear in only one case. In six cases, periodic care is necessary because of retraction to the grafted attic area. The procedure and technique used in these patients and the excellent results are discussed in this article.

Austria↗
PubMed1994

Ultrastructural findings in the cochlea of AIDS cases.

Neurotologic manifestations associated with the human immunodeficiency virus (HIV-1) are poorly understood. Eight temporal bones of acquired immunodeficiency syndrome (AIDS) cases were dissected and investigated ultrastructurally to determine if pathogens and pathologic changes were present within the cochlea. Extracellular viral-like particles with morphologic characteristics of HIV-1 were identified on the tectorial membrane in three cases. Numerous viral-like particles with cores appeared trapped within lacunae along the tectorial membrane in one specimen. Intracellular viral-like particles, appearing essentially similar to identified HIV-1 particles of infected lymphocyte cultures, were found within the cytoplasm of connective tissue cells. These same cells had gradients of enlarged viral envelopes forming cisterns that contained cores and varying amounts of cistern particulate. Some sectioned profiles of enlarged cytoplasmic cisterns revealed the attachment and inward protrusion of the core from the cistern wall. Other ultrastructural findings included cytoplasmic globular-dense particulate bodies, aggregates of smaller viral-like particles, and mitochondrial changes. This demonstration of prominent viral-like particles and cochlear pathology may help to explain the neurotologic manifestations associated with HIV-1 infection.

Adult↗
PubMed1993

Cerebrospinal fluid rhinorrhea and recurrent meningitis.

Cerebrospinal fluid rhinorrhea is the result of transdural communication between the subarachnoid space and the skull base. A transdural fistula may originate from the anterior, middle, or posterior cranial compartments. All skull-base sites of leakage potentially lead to the nasal cavity. Recurrent meningitis is commonly associated with such a direct source of bacterial contamination. Organisms associated with recurrent meningitis secondary to cerebrospinal fluid leaks are commonly found in the upper respiratory tract. We report a case of recurrent meningitis in a 5-year-old girl that highlights the problem of cerebrospinal fluid rhinorrhea, and we discuss etiology, current diagnostic techniques, and surgical management.

Cerebrospinal Fluid Rhinorrhea↗
PubMed1993

Petrous jugular malposition (diverticulum).

Jugular bulb anatomy is variable. A "high-riding" bulb extending into the tympanic cavity is a well-described anomaly. Petrous jugular malposition (diverticulum) (PJMD), however, is rare. The relationship between PJMD and clinical symptoms is questionable because the differentiation between PJMD as an anatomic variant and pathologic process is unproved. A literature review reveals 14 previously documented cases. We report an additional four cases. Diagnostic and management dilemmas are discussed, with the importance of high-resolution CT stressed.

Adult↗
PubMed1993

Unpublished letters from Prosper Menière: a personal silhouette.

It is ironic that, while the term "Menière's disease" is becoming more and more well known today, published accounts of a biographic nature are scarce for the man for whom the eponym was devised: Prosper Menière. As we are obliged to turn to only a few avenues for this sort of information, we are fortunate to discover new sources of original materials to augment the published account of the life and character of Menière the man. One such unpublished source that has recently come to light is a cache of letters from the pen of Menière that was preserved for the period extending from the early 1850s up to the time shortly preceding the author's death a decade later; and it is these letters that form the basis of this inquiry into the mind and character of Menière, the brilliant otologist and man of letters. This particular body of letters, while being for the most part of an admittedly social nature, is of particular interest not only for the occasional references Menière makes to the ear or to his deaf-mute patients, but also because of Menière's epistolary style, and because of their content in general. For this reason the letters have been analyzed primarily with an eye to three categories of interest. The first category is the professional life of Menière, which for the purpose of this paper will be understood to comprise his professional work as a physician, his mention of his patients, of deaf-mutes and their treatment, of his writings in general, and of other pertinent aspects of his medical involvement.(ABSTRACT TRUNCATED AT 250 WORDS)

Correspondence as Topic↗
PubMed1992

Spontaneous temporal bone cerebrospinal fluid leak.

Eight patients with spontaneous cerebrospinal fluid leak of temporal bone origin are presented. Pertinent history and surgical findings are reviewed and contrasted with 33 previously reported patients. Unilateral ear fullness and mild hearing loss are the most common presenting symptoms. Profuse clear otorrhea following myringotomy is virtually pathognomonic. Diagnostic methods including high-resolution computed tomography, magnetic resonance imaging, and contrast cisternography are discussed. The indications for transmastoid and combined transmastoid/middle fossa surgical repairs are compared. Both surgical approaches were found to be equally effective. We favor the transmastoid as the initial approach because of simplicity, safety, and the ability to visualize both the middle fossa and posterior fossa plates as well as the middle ear.

Adult↗
PubMed1991

A newly recognized etiology of Meniére's syndrome. A preliminary report.

Many etiologic agents for Meniére's syndrome have been proposed, suggesting a heterogeneous nature for this disorder. Dissimilar etiologies could, of course, yield disparate responses to uniform treatment. Although electrocochleography has provided us with some objective diagnostic criteria, the actual identification of Meniére's syndrome rests predominantly on clinical criteria. Several of our patients with dysautonomia presented with classical symptoms of Meniére's syndrome. Twenty-five of these patients were treated with increased fluid and sodium intake and flurocortisone, a mineralcorticoid agent. Our favorable results have led us to postulate a heretofore unrecognized etiology for Meniére's syndrome, and speculate on some of the previously reported responses of Meniére's syndrome to corticosteroid treatment.

Audiometry, Evoked Response↗
PubMed1990

High-resolution computed tomography: determination of the cause of pediatric sensorineural hearing loss.

High-resolution computed tomograms (HRCT) reveal strikingly little variation in the dimensions of inner ear structures among people with normal hearing. However, a subgroup of people exist who have a sensorineural hearing loss (SNHL) and morphologically normal HRCT scans, yet have subtle radiographic aberrations based on measurements of inner ear dimensions. These changes might have resulted from teratogenic influences during the late first to mid second trimester, a time when the inner ear has achieved adult form, yet continues to enlarge to adult size. A retrospective study of HRCTs on three groups of ears was performed to determine inner ear structure dimensions. Group I, the control group, consisted of 50 ears with no SNHL and no discernible abnormalities on HRCT. In group II, there were 70 ears with SNHL and obvious abnormalities on HRCT. Group III, the test group, was composed of 140 ears with SNHL and "normal" HRCTs. Groups II and III were analyzed, applying the normal dimensions derived from group I. When compared to the control group (I), all of the ears in group II were abnormal. Moreover, 75% of the ears in group III had subtle differences not apparent unless measurements were made. Two or more abnormal dimensions were found in 32%. Findings and implications are thoroughly discussed.

Adolescent↗
PubMed1989

Perilymphatic fistula in pediatric patients with a preexisting sensorineural loss.

A specific group of 28 children (38 ears) with a preexisting sensorineural hearing loss (SNHL) was studied to determine if a perilymphatic fistula (PLF) was the cause of a progression in their hearing loss. A PLF was identified surgically in six of these ears, but there was no evidence of any defect found in 32 ears. The symptoms shared by the cases in which a fistula was found included a traumatic event (including exertion), CT scan evidence of inner ear defects, hearing threshold decreases of 25 to 30 dB, and vertigo or postural instability.

Adolescent↗
PubMed1989

Cavernous hemangiomas of the internal auditory canal.

Cavernous hemangiomas are vascular malformations that are seldom found in the central nervous system. Four cavernous hemangiomas of the internal auditory canal and one of the cerebellopontine angle have been reported previously. We present a series of seven (six of which have never been reported) cavernous hemangiomas limited primarily to the internal auditory canal. Whereas all cases but one had marked unilateral sensorineural hearing loss, only two had preoperative facial nerve dysfunction. There are no specific symptoms or physical or audiometric findings to differentiate cavernous hemangiomas from acoustic neuromas. However, a hemangioma should be suspected when facial paralysis is present in conjunction with a small intracanalicular tumor as demonstrated by computed tomography or magnetic resonance imaging. The former reveals calcium stippling in the lesions, whereas magnetic resonance imaging reveals a high signal intensity on both T1- and T2-weighted images.

Adult↗
PubMed1988

Dizziness due to dysautonomia: response to specific therapy.

We have reported a case of hypervagal dysautonomia in which there was improvement in the results of autonomic nervous system tests (ANSTs) as well as in the patient's symptoms. This patient is one of more than 200 patients who have had our testing protocol. Although a high percentage of autonomic dysfunction was detected in this group of patients, we do not suggest that these tests be applied routinely to every patient complaining of dizziness. Rather, ANSTs should be selectively administered after otologic disease has been excluded and when dizziness is accompanied by various other symptoms.

Autonomic Nervous System Diseases↗
PubMed1988

Perilymphatic fistula in children with preexisting sensorineural hearing loss.

Progression of preexisting sensorineural hearing loss (SNHL) in infants and children has been considered an indication for fistula exploration: is this approach warranted? On exploring 36 middle ears in 26 such children, we found a perilymphatic fistula (PLF) in four ears (11%). Although there was radiographic evidence of inner-ear deformity in one half of these children, a definite fistula was found in only four of 18 radiographically abnormal ears explored (22%). Even in the four patients with a history of an "event" that could implicate a fistula such as exertion or barotrauma, a fistula was found in only one. There are a number of possible causes for progression of a preexisting SNHL, and surgical exploration of the middle ear should not be recommended on the basis of progression alone. Instead, exploration for a suspected PLF should be strongly considered when there is also a history of an "event", and/or radiographic evidence of inner-ear abnormalities. Even under these conditions, one should be aware that fistulae are not likely to be found.

Adolescent↗
PubMed1986

Dizziness and the autonomic dysfunction syndrome.

Dizziness resulting from inner ear or CNS disease has been well described. However, there is a large number of patients for whom dizziness does not seem to be related to either the ears or the CNS. We postulate an abnormality in the autonomic nervous system of such patients and have used standard tilt testing and Valsalva methods to assess the abnormality. Based on the results of these tests, we can suggest therapeutic options.

Adolescent↗
PubMed1984

Five-year evaluation of reconstructive tympanoplasty using a goblet prosthesis.

This article reviews tympanoplasty using a stainless steel goblet alloplastic prosthesis with a repositioned incus and presents a five-year follow-up report on 51 patients who had this kind of ossicular chain reconstruction. The five-year evaluation shows a better than average success rate compared with other allographic and alloplastic materials.

Chronic Disease↗