PubMed Health⌕ Search

Biomedical subjects

T M McCulloch

Publications and source records attributed to T M McCulloch.

At least 19 recordsLinked to original sources
PubMed2001

The nasogastric tube syndrome: two case reports and review of the literature.

BACKGROUND: The nasogastric tube syndrome is a potentially life-threatening complication of an indwelling nasogastric (NG) tube. The syndrome is thought to result from ulceration and infection of the posterior cricoid region with subsequent dysfunction of vocal cord abduction. This dysfunction may present as complete loss of vocal cord abduction manifested as serious airway compromise. Reports of this syndrome are infrequent, with only 29 cases published to date. METHODS: Two additional cases of nasogastric tube syndrome diagnosed at the University of Iowa Hospitals and Clinics over a 2-year period are presented. A search of MEDLINE (1966 through February 1999), including review of those articles' references identified seven previous publications, including 29 case reports. These 29 cases are reviewed and the findings summarized. RESULTS: Twenty-nine cases of NG tube syndrome are identified, with 16 of these occurring in the preantibiotic period. Including the two cases presented here, 15 contemporary patients are examined. Among these 15 cases, 10 required tracheostomy, on average 8.5 days after NG tube placement. CONCLUSION: Although the fully manifested syndrome presents quite dramatically, we suspect that a clinical spectrum of severity exists with less severe cases going unrecognized. Consistent with previous reports, we found that direct visualization of the postcricoid region is required to rule out the diagnosis and recommend such action be taken whenever the diagnosis is suspected. Treatment should include establishment of a safe airway, removal of the tube whenever possible, antibiotic therapy, and antireflux therapy.

Aged↗
PubMed2001

Vocal process granuloma.

BACKGROUND: This review article reports the evolution of knowledge regarding the benign proliferations of the posterior glottis commonly termed "vocal process granuloma". METHODS: A comprehensive review of publications addressing lesions of the posterior glottis is affected to analyze the contemporary management of vocal process granuloma. RESULTS: Contemporary management emphasizes interventions to decrease irritation to the posterior glottis. Multiple causes of this irritation preclude use of a single management plan that will successfully address all cases. CONCLUSIONS: Management to diminish laryngopharyngeal reflux, as well as to correct vocally abusive behavior, will appropriately address the majority of vocal process granuloma. Surgical removal is best reserved for cases when conservative management fails, when airway obstruction is a concern, or when a biopsy is needed to establish the diagnosis. Ancillary measures that may be beneficial in specific cases include the use of steroids, antibiotics, membranous vocal fold augmentation, and laryngeal botulinum neurotoxin injection.

Glottis↗
PubMed2001

Esthesioneuroblastoma: the University of Iowa experience 1978-1998.

OBJECTIVE: Esthesioneuroblastoma is rare and the best treatment has yet to be defined. The purpose of this study is to analyze the natural history, treatment, and patterns of failure of esthesioneuroblastoma treated at one institution. METHODS: Between 1978 and 1998, 13 patients with esthesioneuroblastoma were identified using the University of Iowa Tumor Registry. All patients were staged according to Kadish criteria. Mean follow-up was 6.3 years. Six patients had 5 or more years of follow-up and four had follow-up exceeding 9.5 years. One patient was lost to follow-up at 36 months. RESULTS: No patients had Kadish stage A disease, five were stage B, and eight stage C. Overall actuarial 5- and 10-year survival rate was 61% and 24%, respectively. Disease-free survival rate at 5 and 10 years was 56% and 42%, respectively. Seven patients have died, three of intercurrent disease and three of disease progression, one with an unknown disease status. Six patients remain alive, three without evidence of disease and three have experienced a local or regional recurrence. Five patients who were initially controlled developed recurrence, three local only, one locoregional, and one regional and distant. Median time to failure was 96 months. All patients with follow-up exceeding 12 years have experienced either a local or regional recurrence. Survival after salvage therapy in these patients ranged from 3 to 12 years. CONCLUSION: Esthesioneuroblastoma has a long natural history characterized by frequent local or regional recurrence after conventional treatment. Successful retreatment can lead to prolonged survival.

Adult↗
PubMed2001

Spindle cell lipoma of the parotid: fine-needle aspiration and histologic findings.

A 47-year-old man presented to the otolaryngologist with a 7-year history of a mass of the cheek. Fine-needle aspiration revealed foci of spindled cells admixed with abundant fat and myxoid material. A diagnosis of spindle cell lipoma was rendered on the resected specimen. The cytologic findings of spindle cell lipoma of the parotid gland as seen by fine-needle aspiration are presented along with the histologic correlates.

Adipocytes↗
PubMed2000

Laryngeal cancer cost analysis: association of case-mix and treatment characteristics with medical charges.

OBJECTIVES: To examine the relationship of various pretreatment case-mix characteristics and treatment modalities with medical charges incurred during diagnosis, treatment, and 2-year follow-up for patients with laryngeal cancer. DESIGN: Retrospective chart review and billing record analysis. METHODS: The charts and billing records of patients diagnosed with laryngeal cancer at the University of Iowa Hospitals and Clinics (UIHC) between January 1, 1991 and December 31, 1994 were reviewed. The independent variables included various pretreatment patient-mix and tumor characteristics (age, AJCC TNM clinical stage, smoking history, ASA class, and comorbidity as defined by Kaplan-Feinstein grade) as well as type of treatment. The dependent variables included total physician, office, and university hospital-based charges incurred during the pretreatment evaluation and 0- to 3-, 3- to 12, and 12- to 24-month billing periods after the initiation of cancer-directed therapy. Total 1-year and 2-year charges were also evaluated. Univariate and multivariate analyses were used to investigate the relationships between dependent and independent variables and to develop models predictive of management charges during the individual and total billing periods. RESULTS: Pretreatment charges showed no significant associations (P < .05) with any of the independent variables. Multiple regression analyses indicated that comorbidity, stage, and initial treatment modality were significant variables in one or more of the models predicting charges incurred during the 0- to 3-month, 3- to 12-month, total 1-year, and total 2-year billing periods. The models yielded R2 values for the total 1- and 2-year billing periods of 0.5246 and 0.5055, respectively. CONCLUSIONS: This work supports continued study of measures that may result in earlier detection of laryngeal cancer as a potential means of reducing management charges. These results also indicate that a more accurate method of stratifying the disease severity of laryngeal cancer patients for reimbursement purposes would include measurements of the severity of the index disease as well as comorbid diseases.

Aged↗
PubMed2000

Arytenoid adduction combined with Gore-Tex medialization thyroplasty.

OBJECTIVE: To describe the technique of combined Gore-Tex medialization thyroplasty with arytenoid adduction and to determine the long-term vocal outcome of patients treated for unilateral vocal cord paralysis with this procedure. STUDY DESIGN: A retrospective chart review and patient reevaluation for patients treated at The University of Iowa Hospitals and Clinics between May 1995 and June 1999. METHODS: The review addressed patient demographics, perioperative and long-term complications, and voice outcomes. Details of the surgical technique are provided within the manuscript. RESULTS: Seventy-two Gore-Tex medialization procedures were completed. Arytenoid adduction was included in 22 of these procedures. This subset of patients was compared with the patients treated with Gore-Tex alone. No major postoperative complications occurred in either group. Preoperative and postoperative voice and videostroboscopy data were available for 19 arytenoid adduction patients and 25 Gore-Tex alone patients. On a seven-point scale (6 [severely abnormal] --> 0 [normal voice]), the average patient rating of voice dysfunction improved from 4.2 to 1.6 (arytenoid adduction) and 4.5 to 2.8 (Gore-Tex alone). Maximum phonation time improved from 6.9 seconds to 16.7 seconds in the arytenoid adduction group. Subjective voice assessment employing the four-point GRBAS scale (3 [severely abnormal] --> 0 [normal]) identified average improvement from an overall grade of 2.1 to 0.8 arytenoid adduction and 2.2 to 1.5 in the Gore-Tex alone group. Improvement was identified in the vocal quality of breathiness from 1.9 to 0.2 (arytenoid adduction) and 1.9 to 0.9 (Gore-Tex alone). CONCLUSIONS: The combined technique of Gore-Tex medialization thyroplasty and arytenoid adduction provide functional results that appear to exceed the improvement attained with medialization alone.

Aged↗
PubMed2000

Functional magnetic resonance imaging using iron oxide particles in characterizing head and neck adenopathy.

OBJECTIVES: In lymph nodes harboring metastases the reticuloendothelial system is replaced by tumor cells and does not concentrate iron particles. This study assesses the value of contrast magnetic resonance imaging (MRI) using ultrasmall superparamagnetic iron oxide particles (Combidex, Advanced Magnetics, Inc., Cambridge, MA) to characterize and stage neck nodes. STUDY DESIGN: Prospective analysis of neck imaging by Combidex MRI, with correlation from pathological assessment of resected lymph nodes. METHODS: Nine patients underwent MRI and subsequent bilateral neck dissections (three), unilateral neck dissections (five) or fine-needle aspiration (one). Each case was evaluated for the number, location, MRI characteristics, and pathological assessment of lymph nodes. RESULTS: Forty-nine separate nodal levels were evaluated with both Combidex MRI and pathological assessment. The presence of metastatic nodal involvement among 45 levels was correctly assessed by the Combidex MRI (three false-negative results, one false-positive result; sensitivity, 84%; specificity, 97%). Analysis was possible for 101 of the individual lymph nodes identified by MRI that could be correlated with individual nodes pathologically examined. Combidex MRI assessment was correct for 99 nodes (one-false positive result, one false-negative result; sensitivity, 95%, specificity, 99%). Standard MRI interpretation without Combidex identified that 12 of 18 nodes (67%) that were greater than or equal to 10 mm (greatest dimension) contained tumor, whereas 9 of 83 nodes (ll%) that were less than 10 mm contained tumor. CONCLUSIONS: Combidex MRI provides functional information to characterize lymph nodes in the clinical staging of squamous cell carcinoma of the head and neck. The inability of MRI to identify small lymph nodes restricts the usefulness of this technique.

Adult↗
PubMed2000

Pharyngeal pressure analysis by the finite element method during liquid bolus swallow.

The human pharynx is unique, acting as a complex interchange between the oral cavity and the esophagus, and between the nasal cavity and the lungs. It is actively involved in the transport of food and liquid, producing the forces that guide the bolus into the upper esophagus and away from the adjacent larynx and lungs. This study developed a biomechanical computer model of the human pharynx, utilizing a finite element method (FEM). Control 2-dimensional cine computed tomography images were obtained during 10-mL barium paste swallows at 8 levels extending from the tongue base to the cricopharyngeal level in order to encompass the entire pharynx. Three-dimensional finite element models of the pharynx were reconstructed from the geometric information obtained from the images at each level. Using an inverse dynamic approach with the addition of known tissue properties, we analyzed the 8 models under estimated pressure histories during swallow. Within each model, changes in the cross-sectional intraluminal area were calculated and compared with the area from the computer-generated FEM model. Area matching allowed estimation of intraluminal pressure gradients during swallow. The estimated pressure gradients were distributed through a range from 10 to 55 mm Hg, varying from one region to another and showing different patterns for the upper 4 levels and the lower 4 levels. The contraction velocity for the upper 4 levels was much higher than that for the lower 4 levels. The higher contraction velocities and pressure gradients in the upper levels are consistent with the bolus velocities required for efficient swallow.

Biomechanical Phenomena↗
PubMed1999

Malignant triton tumor of the head and neck: A case report and review of the literature.

BACKGROUND: Malignant triton tumor (MTT) is a relatively rare, aggressive tumor comprised of both malignant schwannoma cells and malignant rhabdomyoblasts. Because MTT frequently arises in the head and neck, the otolaryngologist must be aware of the nature of the tumor and its response to various treatment modalities. METHOD: This article reviews the treatment and outcome of all reported cases of MTT arising in the head and neck. CONCLUSIONS: Although statistical analysis is limited by the short duration of follow-up of many patients, complete tumor resection appears to carry an improved chance of survival. Adjuvant radiation and chemotherapy may also improve survival, although a benefit of these therapies was not well demonstrated in this small series.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Comparison of viscoelastic properties of the pharyngeal tissue: human and canine.

The viscoelastic properties of the human and canine pharyngeal tissue in tension were evaluated, based on both an experimental protocol-consisting of cyclic load, tensile stress relaxation, and incremental step load tests-and the quasi-linear viscoelastic theory. The reduced stress relaxation function and the elastic response of the pharyngeal tissues were derived from the experimental results specifically obtained from those tissues. The characteristic features of viscoelastic property were obtained for both human and canine pharyngeal tissues by applying the quasi-linear viscoelastic theory and compared with each other. The material properties of the pharyngeal tissue were sought to facilitate the three-dimensional biomechanical model of the pharyngeal function by using the finite element method.

Aged↗
PubMed1999

Contributions of individual muscles to the submental surface electromyogram during swallowing.

Submental surface electromyographic recordings are commonly used in the investigation of swallowing disorders. The measured electromyography is thought to reflect the actions of floor-of-mouth muscles. Although this is a reasonable assumption, to date there have been no investigations to delineate which muscles contribute to this surface recording. The primary goal of this experiment was to determine which muscles contribute most to the submental surface. Electromyography was recorded simultaneously from the submental surface as well as from five individual muscles: mylohyoid, anterior belly of the digastric, geniohyoid, genioglossus and platysma. Three analysis methods were performed to estimate individual muscle contributions: correlation, numeric, and analytic. For the numeric and analytic analyses, a linear model was defined and used to represent the relationship between the surface and intramuscular recordings. Muscles that received a high correlation, numeric and/or analytic value were considered to be primary contributors to the submental recording. Regardless of analysis approach, the primary contributions to the submental surface recording were the mylohyoid, anterior belly of the digastric, and the geniohyoid muscles. Contributions from the genioglossus and the platysma muscles were minimal. Contributions as a function of bolus volume and viscosity are also discussed.

Adult↗
PubMed1999

Electromyographic activity from human laryngeal, pharyngeal, and submental muscles during swallowing.

The durations and temporal relationships of electromyographic activity from the submental complex, superior pharyngeal constrictor, cricopharyngeus, thyroarytenoid, and interarytenoid muscles were examined during swallowing of saliva and of 5- and 10-ml water boluses. Bipolar, hooked-wire electrodes were inserted into all muscles except for the submental complex, which was studied with bipolar surface electrodes. Eight healthy, normal, subjects produced five swallows of each of three bolus volumes for a total of 120 swallows. The total duration of electromyographic activity during the pharyngeal stage of the swallow did not alter with bolus condition; however, specific muscles did show a volume-dependent change in electromyograph duration and time of firing. Submental muscle activity was longest for saliva swallows. The interarytenoid muscle showed a significant difference in duration between the saliva and 10-ml water bolus. Finally, the interval between the onset of laryngeal muscle activity (thyroarytenoid, interarytenoid) and of pharyngeal muscle firing patterns (superior pharyngeal constrictor onset, cricopharyngeus offset) decreased as bolus volume increased. The pattern of muscle activity associated with the swallow showed a high level of intrasubject agreement; the presence of somewhat different patterns among subjects indicated a degree of population variance.

Adult↗
PubMed1998

Risk factors for malignancy in adult tonsils.

BACKGROUND: Tonsillectomy in adults (age 18 years and older) is performed for a variety of conditions. The palatine tonsils may harbor carcinoma or lymphoma, and this potentially unanticipated finding may follow routine tonsillectomy in the adult. The ability to preoperatively identify adult tonsillectomy patients at increased risk for tonsillar malignancy could sensitize the clinician to this possibility and the potential need for expedited rather than routine tonsillectomy scheduling. METHODS: A retrospective review of 476 consecutive adult patients who underwent tonsillectomy during the last 10 years at the University of Iowa Hospitals and Clinics was undertaken. Proposed risk factors for tonsillar malignancy included a prior history of head and neck cancer, tonsillar asymmetry, palpable firmness or visible lesion in the tonsil, neck mass, unexplained weight loss, and unexplained constitutional symptoms. These risk factors were correlated with the pathologic diagnosis in the reviewed cases. RESULTS: Of these 476 patients, 25 had malignant tonsil pathology. No patient without risk factors was found to have malignancy on pathologic evaluation of the tonsils. Of the 25 patients with malignant tonsillar pathology, 23 had two or more risk factors, and 2 patients had one risk factor. Tonsillar asymmetry, found in 20 of the 25 cases, was the risk factor most frequently associated with malignant pathology. CONCLUSIONS: These results indicate that the presence of certain preoperatively identifiable risk factors are associated with the pathologic finding of malignancy in adult tonsillectomy specimens. Based on these criteria, a model which is predictive of the presence of tonsil malignancy may be constructed.

Adult↗
PubMed1998

Patterns of metastases to the upper jugular lymph nodes (the "submuscular recess").

BACKGROUND: Cervical lymphadenectomy to remove metastatic disease in level II encompasses lymph nodes associated with the upper third of the internal jugular vein and the adjacent spinal accessory nerve (SAN). Conservative neck dissection (ND) preserves these structures but requires manipulation of the SAN to remove tissue located in the posterosuperior aspect of level II. Limiting the dissection to the nodal group anterior to the SAN may reduce operating time and limit injury to it without compromising the removal of lymph nodes at risk for involvement with cancer. METHODS: Seventy-one patients with squamous cell carcinoma of the head and neck treated with cervical lymphadenectomy at two separate institutions were prospectively evaluated. One hundred two neck dissection specimens were histologically analyzed for number of lymph nodes present and number involved with cancer. At the time of surgery, level II was separated into the supraspinal accessory nerve component (IIa) and the component anterior to the SAN (IIb). Nodal involvement in level II was analyzed according to characteristics of the cancer at the primary site as well as nodal involvement of other levels. RESULTS: Neck dissections were most commonly done for cancer of the oral cavity (n = 33), followed in frequency by the larynx (n = 17), oropharynx (n = 7), skin of face (n = 4), unknown primary (n = 4), and other sites (n = 6). Eighty NDs were selective and 22 were either radical or modified radical NDs. Pathologic staging of the neck specimen was most commonly N0 (n = 61), followed in frequency by N1 (n= 17), N2 (n= 11), and N3 (n= 11). Data were unclear for two specimens. Level IIb contained an average of 6.9 nodes and the IIa component contained an average of 4.2 nodes. Level II contained metastatic disease in 31 of 39 node positive specimens (79%). Level IIa was involved with cancer in four cases, all of which were preoperatively staged N2 or greater. CONCLUSIONS: The additional time required and morbidity associated with dissection of the supraspinal accessory nerve component of level II may not be necessary when performing elective ND. More research with larger numbers of patients, long-term follow-up, and meticulous tissue analysis is needed to permit conclusions as to where to draw the line in determining extent of cervical lymphadenectomy.

Adult↗
PubMed1998

Incidence of deep venous thrombosis and pulmonary embolism in otolaryngology-head and neck surgery.

OBJECTIVE: Postoperative deep venous thrombosis and pulmonary embolus are major causes of morbidity and mortality in patients undergoing surgical procedures. In contrast to other surgical fields, the incidence of these life-threatening conditions has not been studied in our specialty. The purposes of this study were to elucidate the incidence of deep venous thrombosis and pulmonary embolus in patients after otolaryngologic operations and to identify specific risk factors that may contribute to the development of these conditions. METHODS: A retrospective analysis was done of 12,805 total operations on adults done by the Department of Otolaryngology at our institution from January 1987 to December 1994 to determine the number of patients in whom postoperative deep venous thrombosis and pulmonary embolus developed. Patients in whom a postoperative thromboembolic event developed after an otolaryngologic surgical procedure were identified by the medical records department with use of an abstracting database. This search cross-referenced disease-specific codes for otolaryngologic procedures with the codes for deep venous thrombosis and pulmonary embolus to identify the 34 patients in this report. Results (rounded to the nearest decimal point) were then categorized according to the different subspecialties within otolaryngology, and appropriate statistical analysis tests were performed on the resulting data. RESULTS: Thirty-four patients with postoperative deep vein thrombosis were identified during the study period, for an overall incidence of 0.3%. Of these 34 patients, 24 also had a pulmonary embolus for an overall incidence of 0.2%. The incidence of deep venous thrombosis (and pulmonary embolus) in the subspecialties was as follows: head and neck surgery, 0.6% (0.4%); otology/neurotology, 0.3% (0.2%); head and neck trauma and plastic surgery, 0.1% (0.1%); and general otolaryngology, 0.1% (0.04%). Only the patient's age and the presence or absence of pneumatic compression devices were identified as independent risk factors for the development of a thromboembolic event. CONCLUSIONS: Postoperative pulmonary embolus is a rare occurrence in the field of otolaryngology-head and neck surgery. When it does occur, it causes significant morbidity and increases the cost of care for that patient. We discuss our approach to categorizing patients into low-, intermediate-, and high-risk groups, as well as prophylaxis against pulmonary embolus.

Adult↗
PubMed1998

Cost-identification analysis in oral cavity cancer management.

The objectives of this study were to investigate potential relationships between pretreatment patient-mix characteristics, treatment modalities, and costs generated during the pretreatment work-up, treatment, and 1-year follow-up periods for patients with oral cavity cancer (OCC). Another objective was to identify potential areas for cost reduction and improved resource allocation in the management of OCC patients. Using a retrospective cohort of 73 patients with OCC, pretreatment patient-mix characteristics and treatment modalities were evaluated in relation to university-based charges incurred during the pretreatment evaluation, treatment, and 1-year follow-up periods. Simple regression and stepwise multiple regression analyses were used to develop predictive models for cost based on independent variables, including age, AJCC TNM clinical stage, smoking history, American Society of Anesthesiologists (ASA) class, comorbidity as defined by the Kaplan-Feinstein grade and treatment modality. The dependent measurements included all physician, office, and hospital charges incurred at the University of Iowa Hospitals and Clinics during the pretreatment evaluation, treatment, and follow-up periods, as well as the total pretreatment through 1-year follow-up management costs. Independent variables that were identified as being significantly associated with treatment costs included T classification, N classification, TNM stage, unimodality versus multimodality treatment, and the Kaplan-Feinstein comorbidity grade. Age, smoking status, and ASA class were not significantly associated with costs. The majority of the OCC management costs were incurred during the treatment period. The most substantial decreases in management costs for OCC will be realized through measures that allow identification and treatment of disease at an early stage, in which single-modality treatment may effectively be used. Resource allocation for OCC should support the investigation of measures through which the diagnosis and treatment of OCC at the earliest possible stage is facilitated. The presence of comorbid illness is a significant component in the determination of management costs for OCC and should be included in analyses of resource allocation for OCC. The singular diagnosis of OCC encompasses a wide range of patient illness severity, and diagnosis-related reimbursement schemes for OCC treatment should optimally differentiate between early and advanced stage disease.

Aged↗
PubMed1998

Intra-operative ultrasound-guided drainage of parotid abscess.

Parotitis complicated by parotid abscess remains a potentially life-threatening problem. Conventional surgical treatment involves incising the parotid parenchyma in the direction of the facial nerve until the abscess is located and evacuated. Intra-operative ultrasound greatly assists in localizing the abscess and in ensuring its complete drainage. Expeditious and exact localization of the abscess reduces operative time. Equally importantly, ultrasound-assisted drainage reduces surgical dissection and the potential for facial nerve damage.

Abscess↗