Search PubMed⌕ Search

Biomedical subjects

D H Rice

Publications and source records attributed to D H Rice.

At least 73 records · Page 4Linked to original sources
PubMed1993

Thyroarytenoid intramuscular pressures.

The aim of this research has been to investigate the measurement of laryngeal intramuscular fluid pressures as a technique for assessment of laryngeal muscle activity for diagnostic or experimental purposes. Simultaneous measurements of contractile force, intramuscular fluid pressure, and electromyographic signals were made under isometric conditions in the vocal fold muscles of anesthetized dogs during supramaximal stimulation of the recurrent laryngeal nerve. Covariation of force and pressure was studied in twitch and tetanic contractions, over a range of stimulation frequencies. Tetanic pressure rises were usually smaller than in human limb muscles, but were of sufficient magnitude that effects on blood flow and muscle metabolism are probable. Analysis of relations between pressure and force records demonstrated that intramuscular pressure variations correlated closely to isometric force in their time course. This finding suggests the potential significance of this measure as a relatively nonintrusive indicator of the level of force of muscles involved in laryngeal function, and as a physiological measure of importance.

Animals↗
PubMed1993

Idiopathic facial nerve paralysis: a randomized double blind controlled study of placebo versus prednisone.

Idiopathic facial nerve paralysis (IFNP) is a common malady. Because its etiology is unclear, there are a variety of treatment options. Studies to date have not clearly established the benefits of treatment with oral steroids (prednisone). The authors performed a randomized double-blind controlled study comparing the use of placebo versus prednisone which shows that prednisone-treated patients benefit from early treatment. Seventy-six patients met inclusion criteria and completed follow-up until recovery; 35 patients received prednisone and 41 received placebo. Their mean age was 36.8 years. Facial nerve function was assessed using the House-Brackmann facial nerve grading scale, as well as a variety of other measures. Patients were evaluated pretreatment, regularly post-treatment until judged recovered (return of facial function to a grade III or better), and at 6 months after recovery. Difference in mean time to resolution for the prednisone (51.4 days) and placebo (69.3 days) groups was not statistically significant. There was a significant difference in grade at recovery, with the placebo group having a higher proportion of grade III results (P < .03). Eight of 10 patients with electroneurography (ENOG) evidence of denervation were in the placebo group and accounted for 6 of the 7 grade III results. However, the difference in proportion of patients with evidence of denervation for the prednisone (5.7%) and placebo (19.5%) groups did not achieve statistical significance. This study shows that patients treated with prednisone have less denervation than placebo-treated patients. They also have a significant improvement in facial grade at recovery compared to placebo-treated patients. Therefore, the authors recommend that all patients at risk for developing denervation receive prednisone treatment.

Adolescent↗
PubMed1993

Sinoscopy.

Endoscopic sinus surgery is relatively new to the United States, having been imported from Europe in 1985. It has brought about a new way of looking at and treating chronic bacterial infections of the paranasal sinuses. The advance in technology rests on the development of the computed tomography scan as well as on the more recent development of the sinus endoscopes. These two technologies allow one to make a diagnosis of much more subtle chronic bacterial sinus infections than was possible in the past. In addition, it allows for more directed treatment in a way that spares mucosa, allowing for faster and better healing.

Endoscopes↗
PubMed1993

Endoscopic sinus surgery.

Successful endoscopic sinus surgery requires a thorough knowledge of the anatomy of the paranasal sinuses and, in particular, the lateral nasal wall. This article discusses a variety of topics relating to endoscopic sinus surgery, including physiology, patient evaluation, several surgical techniques, postoperative care, and complications.

Endoscopy↗
PubMed1993

Chronic frontal sinus disease.

A variety of procedures are now available to manage chronic frontal sinus diseases. The choice of procedures depends upon both the extent of the disease and the experience of the surgeon.

Chronic Disease↗
PubMed1992

Flutamide-induced regression of angiofibroma.

Juvenile nasopharyngeal angiofibroma (JNA) appears to be an endocrine-responsive tumor. This concept was tested in five young men with JNA by treating them with a testosterone receptor blocker (flutamide) for 6 weeks preoperatively. Tumor size was evaluated by axial computed tomography both before and after flutamide therapy. Four of the five patients had an average tumor shrinkage of 44%. The patients tolerated the drug well, and the serum testosterone levels 2 or more years posttherapy were normal. This pilot study demonstrate that preoperative hormonal pharmacoreduction of JNA is a feasible adjunct to surgical therapy that offers the possibility of reduced blood loss. However, the authors believe that a formal clinical trial of this treatment approach is warranted and should be done before widespread adoption of this agent.

Adolescent↗
PubMed1991

Resident work hours and working environment in otolaryngology. Analysis of daily activity and resident perception.

OBJECTIVE: --To analyze the working environment and work hours of a cohort of otolaryngology--head and neck surgery residents. DESIGN: --Environmental analysis questionnaire and a log of daily activities. SETTING: --Residents were on a clinical rotation system. PARTICIPANTS: --Fifty-nine residents from six programs, including three public and three private institutions, from geographically diverse regions of the country were involved in the study. Residents were equally distributed from their second year through their fifth year of postgraduate work. All eligible residents participated in and completed the study. INTERVENTION: --The environmental analysis survey was designed to elicit resident perception of different aspects of their working environment. The daily activity log required the resident to report on activities for each half-hour period for 7 consecutive days. RESULTS: --Residents were on call an average of 52.8 hours (2.2 days) and worked 79.4 hours per week. Seventy-five percent believed that the level of faculty supervision and the degree of resident responsibility was about right. Two major inefficiencies were the time involved in completion of paperwork and the lack of nonmedical support services. Thirty-one percent of the residents responded that fatigue resulted in substandard patient care 10% of the time. Forty-seven percent responded that their educational experience was substandard 25% of the time secondary to fatigue. Two thirds responded that the demands of residency training had a negative impact on their family and personal life. CONCLUSIONS: --Seventy percent of the otolaryngology--head and neck surgery residents surveyed at six institutions believe that an 80-hour workweek, including being on call every third night with no more than 24 hours of continuous work without sleep, approximates a reasonable, maximum work schedule. Residents working the longest hours expressed concern about rendering substandard care and developing negative attitudes toward patients. Noneducational inefficiencies were identified and solutions were proposed. Demands of residency training, even within guidelines established as reasonable, can have detrimental effects on residents' educational activities and personal life.

Attitude↗
PubMed1991

Snoring and obstructive sleep apnea.

Evidence shows that snoring and obstructive sleep apnea have significant negative physiologic consequences. These patients should be treated expeditiously once the diagnosis is made and carefully followed to ensure that improvement is maintained.

Humans↗
PubMed1991

Immediate versus chronic tissue expansion.

A quantitative comparison of the effects on tissues is performed between chronic tissue expansion, intraoperative expansion, and load cycling in a guinea pig model. Intra-operative expansion, which was developed by Sasaki as a method of immediate tissue expansion for small- to medium-sized defects, and load cycling, which was described by Gibson as a method using intraoperative pull, are compared with chronic tissue expansion on the basis of the following four parameters: amount of skin produced, flap viability, intraoperative tissue pressures, and histological changes. The chronically expanded group, which included booster and nonbooster expansions, produced a 137% increase in surface area, or a 52% increase in flap arc length, whereas intraoperative expansion resulted in a 31% increase in surface area, or a 15% increase in flap arc length. The load-cycled group, however, resulted in an almost negligible amount of skin increase. All three techniques exhibit immediate postexpansion stretchback. Flap viability is not impaired by any of the three techniques, in spite of the elevated pressures observed during expansion. Therefore, intraoperative expansion is effective primarily for limited expansion of small defects, whereas chronic tissue expansion still provides the greatest amount of skin increase when compared with other techniques.

Animals↗
PubMed1991

Intraoperative recurrent laryngeal nerve monitoring.

Intraoperative nerve monitoring has become common for surgical procedures in which cranial or peripheral nerves may be compromised. Intraoperative monitoring of recurrent laryngeal nerve function can be accomplished by recording electromyographic activity from fine-wire electrodes placed in the vocalis muscle. The technique and instrumentation for this are adapted from those used in intraoperative facial nerve monitoring for acoustic neuroma excision. Specifically, a commercially available instrument, the XOMED-NIM provides the capability for monitoring the vocalis muscle electromyogram by means of visual and auditory display. It also provides the capability for performing evoked electromyographic tests of nerve integrity. Intraoperative monitoring of the recurrent laryngeal nerve during thyroidectomy may assist in the more precise dissection of the nerve as well as in verification of nerve integrity during the operative procedure, thus reducing the risk of injury.

Electrodes↗
PubMed1990

Endoscopic intranasal dacryocystorhinostomy results in four patients.

Dacryocystorhinostomy is commonly performed through an external incision. Several transnasal approaches were described earlier in this century but they failed to gain popularity probably because of the difficult exposure. The recent development of nasal endoscopes has greatly improved intranasal visualization. A prior cadaver study demonstrated the feasibility of a transnasal approach. This study presents early results on four patients.

Dacryocystorhinostomy↗
PubMed1990

Evaluation of an enzyme immunoassay for the detection of herpes simplex virus (HSV) antigen from clinical specimens in viral transport media.

A total of 301 clinical specimens (229 culture positive and 72 culture negative) were assayed retrospectively by an enzyme immunoassay. Specimens were transported to the virus lab in viral transport media (VTM), and were inoculated into HF and A549 cell culture tubes for viral isolation with the remainder of the sample being saved at -70 degrees C. Specimens were thawed, vortexed and resuspended in 10 x Herptran concentrate and each sample was then added in duplicate to designated wells of a microtiter plate for the EIA assay. The EIA detected 147/150 (98%) culture positive specimens from symptomatic patients, 63/79 (79.7%) culture positive specimens from patients considered asymptomatic and 210/229 (91.7%) culture positive specimens overall. The EIA was negative for 70/72 (97.2%) culture negative specimens. These data suggest that the EIA test can be used with clinical specimens submitted in conventional VTM. However, VTM samples which are EIA negative, particularly with EIA values close to the EIA positive cutoff value, need to be cultured.

Antigens, Viral↗
PubMed1990

Use of serum substitutes for the growth of four cell lines commonly used for virus isolation.

Four serum extenders (Opti-MEM I, BioRich, Excyte I and Excyte III) and two serum substitutes (Omni Serum and Serum Plus) were evaluated for the reduction or replacement of FBS for the growth and maintenance of four representative cell lines used for virus isolation. MRC-5, human fetal foreskin fibroblast (HF), A549 and Hep-2 cells were seeded into culture flasks containing MEM with 10% FBS or with the serum extenders or substitutes and subcultured into 16 x 125 mm glass tubes and 1-dram shell vials. Only cells cultured with Opti-MEM I and Omni Serum grew consistently in tubes and vials and these reagents were compared to FBS for viral isolation and detection. Laboratory stocks of CMV, HSV, VZV, adenovirus (Ad) and RSV were tested. In HF and MRC-5 cells, CMV was isolated in cells cultured in either Opti-MEM I or Omni Serum before CPE appeared in cultures containing FBS. Ad and VZV CPE were observed first in HF and MRC-5 cells containing Omni Serum. HSV CPE was seen at the same time in HF and MRC-5 cells with all 3 media. HSV and Ad CPE in A549 cells were also seen at the same time in all 3 media. RSV and Ad CPE in Hep-2 cells were observed first in FBS containing media. Both Opti-MEM I and Omni Serum performed well as substitutes for FBS for growth of stock viruses without loss of cell sensitivity.

Animals↗
PubMed1990

Wound infections and recurrence in head and neck cancer.

Recent publications in the general surgery literature have reported improved survival in abdominal cancer surgery in those in whom a postoperative wound infection develops. We reviewed our experience with 100 consecutive patients operated on for head and neck cancer. All patients had 5-year followup. The complete report covers site and stage. In summary, for all cancers of the larynx (N = 60), the recurrence rate was 45% for those in whom a wound infection developed and 26% for those in whom no such infection developed. For cancers of the oral cavity and pharynx (N = 40), the recurrence rate was 80% for those in whom wound infections developed and 51% for those who had no infections. Because of the small number of patients in whom recurrence developed, with or without infection, the relationship does not reach statistical significance. For head and neck cancer, unlike abdominal cancer, the development of a postoperative wound infection may have an adverse effect on survival rather than a salutory effect.

Adult↗
PubMed1990

Fatigue resistance of canine vocal fold muscle.

The objective of the experiment was to provide data from dogs, the best nonprimate model for the contractile properties of laryngeal muscles, on the fatigue characteristics of vocal fold muscle. Isometric muscle force was recorded from a transducer attached to the section of the thyroid cartilage on which the muscle inserted. Twitch contractions were recorded during supramaximal indirect electrical stimulation by DC pulses for at least 30 minutes. At 5 pulses per second (p/s), potentiation was observed in all records, peaking at an average of 7.5 minutes after stimulation onset. At 10 p/s, the peak of the potentiated average trace was earlier. One third of these records did not show potentiation. Where moderate or large potentiation was observed, the peak twitch tension declined and reached an asymptote above the initial tension, while when potentiation was small or absent, the final force was smaller than initially. Canine vocal fold muscle was observed to be fatigue-resistant, but in phonation other factors may produce fatigue.

Animals↗