First derivative of the apex cardiogram and systolic time intervals in evaluation of myocardial contractility in man.

The sensitivity of various systolic ... myocardial contractility.

Rhabdomyosarcoma of the middle ear: imaging features in two children.

The imaging features are presented in two cases of rhabdomyosarcoma arising from the middle ear during childhood, an extremely rare and aggressive neoplasia. CT provides excellent information concerning the degree of bone involvement; contrast-enhanced MR imaging clearly delineates subcranial and/or intracranial extension.

Nodal volume reduction after concurrent chemo- and radiotherapy: correlation between initial CT and histopathologic findings.

BACKGROUND AND PURPOSE: The role of concurrent chemoradiation for treatment of head and neck squamous cell carcinoma is expanding. We sought to evaluate the CT appearance of diseased and normal cervical lymph nodes before and after concurrent chemoradiation and to correlate lymph node volume reduction as revealed by CT with histopathologic findings of resected nodes. METHODS: Using concurrent chemoradiation, we treated seven patients with locally advanced head and neck squamous cell carcinoma. Our chemotherapeutic regimen consisted of cisplatin (100 mg/m2 body surface area administered on days 1 through 4 and 29 through 32) and 5-fluorouracil (1000 mg/m2 body surface area, administered on days 1 through 4 and 29 through 32). Radiotherapy was administered twice per day on dosing days 1 through 42 to a total dose of 7200 cGy to the primary tumor and 6000 cGy to the involved lymph nodes. Pre- and post-treatment CT scans were used to calculate lymph node volumes for all CT-positive (size criteria or extracapsular spread or both) diseased nodes (n = 19) and one normal node per patient (n = 7). Volume reduction was determined by CT results and correlated with the histopathologic findings of resected nodes. RESULTS: Average volume reduction (+/- standard error of the mean) for the 19 diseased nodes was 91%+/-4% and for the seven normal nodes was 55%+/-21% (P < .02, two-sided t test). Fifteen of 19 of the diseased lymph nodes showed extracapsular spread before treatment and none of 19 after treatment. The histopathologic findings of resected nodes included persistent tumor in one of the 19 diseased lymph nodes. Six of seven patients remained alive and disease-free, with an average follow-up duration of 24 months. CONCLUSION: Nodal volume reduction of greater than 90% was associated with eradication of tumor as assessed by histopathologic analysis of resected nodes. Serial CT scans obtained both before and after concurrent chemoradiation may be useful for predicting which patients will benefit from adjuvant surgical therapy.

Significance of ploidy in laryngeal cancer.

We studied 48 patients with laryngeal or hypopharyngeal primary tumors with DNA flow cytometry. Twenty-four of the tumors were glottic, 18 were supraglottic, and 6 were from the pyriform sinus. Patients were followed for a minimum of 12 months, with a mean follow-up of 23 months. Twenty-three of the 48 primary tumors (48 percent) were clearly aneuploid, 22 percent were tetraploid, and 30 percent were diploid. We concluded that patients with aneuploid primary tumors, high DNA levels, or both have a significantly better prognosis than those with diploid tumors, and this remained statistically significant when clinical outcome was adjusted for tumor status, stage, and nodal status.

Vascular tumors of the head and neck: presentation, prognosis, and treatment dilemmas.

Vascular tumors of the head and neck are a heterogeneous group of neoplasms, ranging from such common, benign lesions as facial hemangiomas to rare malignant tumors such as angiosarcomas. Because many of these tumors are quite rare and may occur in areas unfamiliar to the non-otolaryngologist, such as the nasopharynx, larynx, and middle ear, their presentation and differential diagnosis may not be familiar to the general medical practitioner. In addition, the treatment of many of these lesions is still evolving, with the advent of preoperative embolization and laser excision improving the morbidity of what may still be a difficult surgical removal. The authors review the presentation, treatment, and prognosis of the more common vascular tumors of the head and neck.

Measurement of cochlear blood flow: intravital fluorescence microscopy.

A technique is described for directly observing in vivo cochlear microvasculature in the gerbil for physiologic and experimentally induced changes in vessel diameter and blood flow velocity. Measurements are made from computer processed video images of surgically exposed microvessels. These images are obtained using intravital fluorescence microscopy (IFM) with epi-illumination. The Mongolian gerbil is an ideal animal model for circulatory studies of the inner ear. It has a stable heart rate and blood pressure under urethane/alpha-chloralose anesthesia and its cochlea is surgically accessible. A window is created over the feeding artery (anterior inferior cerebellar artery) and over the stria vascularis of the second turn of the cochlea, atraumatically exposing radiating arterioles and strial capillaries. Our system of IFM provides images that are videorecorded, digitally analyzed with a computer image processor, and enhanced according to the type of measurement desired. Velocity measurements are obtained by tracking plasma gaps or single fluorescent labeled red blood cells through successive frames of the videorecorded images. This experimental technique allows us to analyze circulatory responsiveness to a variety of vasoactive drugs administered regionally to the cochlea in concentrations not affecting systemic circulation.

Immunocytochemical localization of aspartate and glutamate in the peripheral vestibular system.

Controversy exists concerning the identity of the neurotransmitter in the mammalian peripheral vestibular system. Several candidates have been proposed, including the excitatory amino acids glutamate and aspartate and the inhibitory amino acid gamma-aminobutyric acid (GABA). Previous studies have demonstrated vestibuloneural electrophysiological activity associated with glutamate and aspartate. Paraffin sections of rat vestibular ganglia and end-organs were examined for the presence of glutamate-like and aspartate-like immunoreactivity. Our results demonstrate the presence of both aspartate-like and glutamate-like immunoreactivity in vestibular hair cells, peripheral vestibular nerve fibers, and vestibular ganglion cells. Minimal immunoreactivity was noted in the tissues surrounding these cells. These data add support to the hypothesis that the excitatory amino acids glutamate and aspartate are involved in vestibular neurotransmission.

Effect of sodium nitroprusside on compound action potential thresholds in the gerbil cochlea.

The presence of active nitric oxide synthase (NOS) in the spiral ganglion cells of the cochlea suggests that the neuromodulator nitric oxide (NO) may play a role in hearing. This study investigated the effects of sodium nitroprusside (SNP), an NO donor, upon cochlear function mediated through its activation of guanylate cyclase. In gerbils, cochlear compound action potential (CAP) thresholds were recorded after cochlear perfusions of control and test solutions in four experimental groups. Perfusions were performed using the following: artificial perilymph solution (APS); the NO donor SNP; the guanylate cyclase inhibitor methylene blue (MB); and sodium dodecyl sulfate (SDS), which facilitates MB entrance into cells. SNP caused significant elevations of CAP thresholds from baseline (25 dB SPL +/- 1.54 dB to 64.3 dB SPL +/- 2.54 dB). SNP with MB also resulted in significant CAP threshold elevations (29.4 dB SPL +/- 4.27 dB to 38.1 dB SPL +/- 4.0 dB); however, these elevations were significantly lower than those seen in SNP perfusions without MB. Drilling perfusion holes and perfusion of APS, APS/SDS, and MB/SDS/APS solutions did not significantly affect CAP thresholds. These results suggest that the NO donor nitroprusside does affect cochlear neuromodulation and effects this mediation in part through NO activation of guanylate cyclase.

Immunocytochemical localization of contractile and contraction associated proteins in the spiral ligament of the cochlea.

Most of the extracellular fibers of the spiral ligament are associated with a distinct band of 'anchoring' cells which occur at the boundary between the spiral ligament and the otic capsule. These cells are characterized by parallel arrays of intracellular filaments which, along with the extracellular fibers, insert into electron dense, conical adhesion plaques. The intracellular filaments show a close morphological resemblance to the 'stress fibers' of cultured fibroblasts (Henson et al., 1984). In the present study we have demonstrated by immunofluorescence techniques that the anchoring cells, unlike adjacent cells of the spiral ligament, contain a complement of proteins that is typically associated with stress fibers and with contractile systems. In addition to actin, the cells contain myosin, tropomyosin, alpha-actinin and talin. These results lend further support to the hypothesis that the anchoring cells have the capacity to create and/or maintain tension on the spiral ligament-basilar membrane complex and to influence the mechanical properties of the basilar membrane.

Nitric oxide synthase is an active enzyme in the spiral ganglion cells of the rat cochlea.

Nitric oxide (NO) mediates the effects of the excitatory amino acids in the central nervous system. Excitatory amino acids, in particular L-glutamate, are thought to be the neurotransmitter(s) present at the cochlear hair cell-afferent nerve synapse. To our knowledge, no studies to date have documented the presence of NO in the cochlea nor attempted to elucidate the role of NO in hearing. Rat cochlea frozen sections were examined for the presence of nitric oxide synthase (NOS) by NADPH diaphorase histochemistry. Vibratome sections of rat cochlea were examined by immunocytochemistry with an antibody to citrulline, an indication of NOS activity. Spiral ganglion cells in the rat cochlea were positive by NADPH diaphorase histochemistry and by anti-citrulline immunocytochemistry. These results indicate that NOS is present and that the enzyme actively produces nitric oxide in the spiral ganglion cells of the rat cochlea. Given our current understanding of neurotransmission in the cochlea, it is reasonable to postulate that the actions of NO in cochlear neuronal tissue are similar to the actions of NO in the CNS and that NO acts as a neurotransmitter/neuromodulator in the cochlea. In addition, because NO has been implicated as a mediator of excitotoxicity in the CNS, NO may play a role in neurotoxicity in the cochlea.

Hypertension, hyperlipoproteinemia, chronic noise exposure: is there synergism in cochlear pathology?

The purpose of this research is to establish in laboratory animals whether a relationship exists among noise exposure, hypertension, and hyperlipoproteinemia. A discussion of the historical background leading to this work is presented. Previous investigations dealing with each of the three variable, noise, hypertension, and hyperlipoproteinemia, as they relate to hearing, are discussed. Methodology, including new methods developed during this study, will be presented. Results support the concept that a significant relationship does exist among noise, hypertension, hyperlipoproteinemia, and hearing loss.

Luetic hydrops--diagnosis and therapy.

Nine patients presenting at the Shea Clinic over the past eight years with a history of fluctuant hearing loss were subsequently found to have neurosyphilis. Treatment has consisted of penicillin, given by various routes, oral steroids and vasodilator therapy. We have, based on recent investigations, begun using high dose intravenous penicillin in this regimen. Results have been encouraging in two patients, with rapid improvement in hearing. A protocol outline for diagnosis and therapy of syphilis is included in the discussion.

Histiocytosis X of the head and neck.

Histiocytosis X is a general disease class for three less distinctive and overlapping states; namely, eosinophilic granuloma, Hand-Schuller-Christian disease, and Letterer-Siwe disease. These conditions span a continuum from an isolated bony or soft tissue lesion to a fulminant, disseminated process. The head and neck are frequent sites of initial presentation for the more serious varieties. We present four cases of histiocytosis X with lesions in the temporal bone, skull, and mandible. Some patients had accompanying scalp lesions as well as other distal bony and soft tissue lesions. Treatment included radiation therapy, chemotherapy, and surgery. A rational discussion of new treatment modalities based on stage of the disease is presented. Utilization of CT scanning in the initial diagnosis and follow-up is demonstrated. Management of troublesome otologic complications is also discussed.

Acoustic reflex abnormalities in behaviorally disturbed and language delayed children.

Contralateral and ipsilateral acoustic reflex thresholds were measured in 62 subjects referred for suspected delays in development of language, learning disabilities, or disorders of auditory processing, with normal peripheral hearing thresholds and normal tympanometry. Thirty-two percent of the subjects in this study showed abnormal contralateral and ipsilateral acoustic reflex thresholds. Both contralateral and ipsilateral acoustic reflex thresholds were involved when subjects showed abnormal reflex thresholds. Although a high percentage of abnormal acoustic reflexes occurred in this population, no strong correlation could be found with specific areas of language delay. A slight positive correlation was found between abnormal acoustic reflexes and delayed psychomotor development. Increased or absent acoustic reflex thresholds are usually associated with peripheral or low brain stem pathologies. While not conclusive, these results suggest brain stem involvement in this population.

Interaction between hypertension and diabetes mellitus in the pathogenesis of sensorineural hearing loss.

The purpose of this study is to support the hypothesis that diabetic end-organ damage of the cochlea is augmented in the setting of hypertension. A historical perspective reviewing the effects of diabetes and hypertension as causative factors in the development of sensorineural hearing loss, as well as the basic epidemiology and pathophysiology of the renal and vascular effects of diabetes and hypertension, is presented. The results of audiologic findings in insulin-dependent diabetic patients, both normotensive and hypertensive, were analyzed and correlated with the results of animal studies to support the hypothesis that sensorineural hearing loss in patients and cochlear hair cell loss in animal studies result from the effects of hypertension in conjunction with insulin-dependent diabetes mellitus.

Primary tumors of the facial nerve: diagnosis and management.

Benign primary tumors of the facial nerve are frequently misdiagnosed because of variable and subtle clinical manifestations. Three such cases of facial nerve neuroma seen in the past 3 years will be presented. Difficulties in patient assessment including the lack of specificity for topographic testing, as well as the capricious behavior of the facial nerve in these patients will be discussed. The efficacy of diagnostic techniques presently available and in use including computerized tomography and electrodiagnostic studies will be discussed. Diagnosis of these tumors might generally be thought to be straightforward and easier with the advent of new diagnostic techniques, but this has, in fact, not been the case. Techniques for removal and repair will be presented. The combined approach utilizing the mastoid and middle fossa will be presented.

Tracheal reconstruction with pedicled thyroid cartilage.

Limited areas of tracheal stenosis have been repaired with a variety of techniques. More extensive upper tracheal defects present a greater challenge with less predictable success. The following is the description of yet another technique for reconstruction of extensive upper tracheal defects. We report on the use of a muscle-pedicled thyroid alar graft which carries its own blood supply and perichondrial covering, supplies a large, conveniently shaped graft, requires one operative site and one operative sitting, and has proven advantageous even in the comprised patient.

Severe hospitalized croup: treatment trends and prognosis.

We have reviewed 43 cases of severe croup admitted from 1977 to 1981 at North Carolina Memorial Hospital. All patients were treated with mist, 23 (54%) of 43 were treated with racemic epinephrine, but only 7 (16%) of 43 were treated with steroids. None of the 5 patients who required intubation received steroids. Nine (36%) of 25 patients available for at least 6 months of follow-up had subsequent clinical diagnoses of asthma. We have concluded that: 1. males with subglottic narrowing on x-ray, high leukocyte counts, and no steroid treatment appear to have increased need for airway support; 2. while humidification and racemic epinephrine are accepted forms of treatment, steroids are still rarely used even in severe croup; 3. severe croup may be a signal for the later development of asthma. Because it is difficult to predict which patients with severe croup will need later airway management, we strongly recommend that all patients with croup requiring racemic epinephrine be treated with at least a single dose of 1.0 to 1.5 mg/kg of dexamethasone.

Insulin-dependent diabetic microangiopathy in the inner ear.

Thickening of the basement membrane in capillaries is implicated in the microangiopathic complications of diabetes mellitus. This study was designed to evaluate microangiopathic changes of the inner ear associated with insulin-dependent diabetes mellitus (IDDM) and concurrent moderate-intensity noise exposure. Male Sprague-Dawley rats were injected with streptozotocin (65 mg/kg) to induce IDDM. Half of the control and diabetic animals were exposed to chronic noise of 95 dB over the 6-month study period. Photomicrographs of the capillaries in the stria vascularis were obtained by transmission electron microscopy, and basement-membrane thickness was measured with an image processing system. This study quantitatively demonstrates basement-membrane thickening consistent with diabetic microangiopathy in the inner ear of IDDM rats. Noise exposure did not significantly change basement-membrane thickness in either diabetic or control animals.

Tracheotomy and the intensive care unit patient.

Transportation of the intensive care unit (ICU) patient to the operating room for tracheotomy has been implicated as an unnecessary source of complications and has been cited as a relative indication for percutaneous tracheotomy. However, there is very little evidence in the literature to support this claim. We evaluated 100 consecutive patients who were transported from the ICU to the operating room for tracheotomy. There were no complications related to patient transportation. A total of five complications occurred, all unrelated to patient transportation. Two patients receiving pressure control ventilation developed a pneumothorax on postoperative days 7 and 8, respectively. There were three minor complications directly related to the tracheotomy: peristomal cellulitis, tracheitis, and hemorrhage of less than 25 cc on postoperative day 1. The minor complications were treated appropriately and resolved without any adverse sequelae. We provide a detailed review of 100 consecutive ICU patient tracheotomy cases and compare this with 109 tracheotomies in non-ICU patients. Transportation of the ICU patient does not appear to increase the risk of complications during tracheotomy and should not be cited as a cause of complications in the percutaneous tracheotomy literature. The results with standard surgical tracheotomy in the controlled setting of the operating room should serve as the standard by which other procedures are judged.