Orbital dermoid cysts: clinicopathologic correlations, classification, and management. The 1997 Josephine E. Schueler Lecture

The dermoid cyst is one of the most common space-occupying orbital lesions, but there has been no large series that details the clinical, pathologic, and therapeutic aspects of this condition. Furthermore, despite the various presentations and types of dermoid cysts, there is no clinically applicable classification of these lesions. We performed a retrospective histopathologic study of 197 consecutive orbital and periorbital dermoid cysts excised at Wills Eye Hospital during a 32-year period, correlated the histopathologic findings with the recorded clinical and radiographic observations, and devised a clinically applicable classification of orbital dermoid cysts. The mean age at excision was 17 years (range, 5 months to 85 years), and the most frequent clinical finding was a painless subcutaneous mass, present in 89% of cases. In 72% of patients, the mass was located in the superotemporal orbital region and produced no abnormalities of vision or intraocular pressure. Computed tomography and magnetic resonance imaging, performed mainly in the more recent cases, disclosed a characteristic round to ovoid cystic lesion with a well-defined lining. Histopathologically, 165 of the cysts (84%) were lined by keratinizing, stratified squamous epithelium. Ten (5%) were lined by nonkeratinizing epithelium resembling conjunctival epithelium. Hair shafts were present in the wall or lumen of the cyst in 195 (99%) of specimens, sebaceous glands in 148 (75%), and sweat glands in 39 (20%); inflammation was present in 75 cases (38%). Based on these personal observations and a review of the literature, a classification of orbital dermoid cysts is proposed that we believe will provide guidance for the ophthalmologist in the management of these lesions.     

The 1997 Schering Lecture. Quality of life in oncology: nurses' perceptions, values and behaviours

Quality of life is an important dimension of cancer care. Yet, within our current environment of fiscal restraint, restructuring and cancer care system reform, pressures exist which may make it difficult to provide care which attends to issues of quality of life. Oncology nurses are key providers of cancer care and their perspectives on quality of life for cancer patients are very important. In addition, much of the satisfaction oncology nurses experience in their practice emerges from matters related to attending to quality of life issues. Are oncology nurses currently able to incorporate quality of life issues into their daily care of patients? How are they doing so? The purpose of this qualitative study is to identify major themes and dimensions of nurses' perceptions and values related to quality of life and create a profile of the oncology nurse's role in integrating quality of life in nursing practice. A total of 25 oncology nurses in regional cancer centres across Ontario were interviewed. Each semistructured interview was taperecorded and transcribed. Analysis was completed to identify the major themes and dimensions. This presentation will report the findings from the study and will focus on understanding the existing values oncology nurses hold surrounding quality of life, how quality of life is conceptualized, and the patterns of practice and decision-making regarding quality of life.     

Breast disease: Etiology, prevention, and rehabilitation.

A theoretical model is presented that takes etiological factors into account in describing behavioral and constitutional factors associated with fibrocystic disease and breast cancer. The model identifies 5 variables: genetic background and familial history; life cycle events; dietary habits; use of exogenous estrogens; and psychological factors, including life stresses, anxiety or tension, and depression. Most of the variables are hypothesized to increase the risk of breast pathology by inducing physiological changes—specifically, by fostering endocrinopathy or immunosuppression. Supportive research is cited, and the relationship between fibrocystic disease and breast cancer is detailed. Implications for prevention and for rehabilitation of women with breast disease are described. (91 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toynbee Memorial Lecture 1997. Middle ear mechanics in normal, diseased and reconstructed ears

A review of the structure-function relationships in normal, diseased and reconstructed middle ears is presented. Variables used to describe the system are sound pressure, volume velocity and acoustic impedance. We discuss the following: (1) Sound can be transmitted from the ear canal to the cochlea via two mechanisms: the tympanoossicular system (ossicular coupling) and direct acoustic stimulation of the oval and round windows (acoustic coupling). In the normal ear, middle-ear pressure gain, which is the result of ossicular coupling, is frequency-dependent and smaller than generally believed. Acoustic coupling is negligibly small in normal ears, but can play a significant role in some diseased and reconstructed ears. (2) The severity of conductive hearing loss due to middle-ear disease or after tympanoplasty surgery can be predicted by the degree to which ossicular coupling, acoustic coupling, and stapes-cochlear input impedance are compromised. Such analyses are used to explain the air-bone gaps associated with lesions such as ossicular interruption, ossicular fixation and tympanic membrane perforation. (3) With type IV and V tympanoplasty, hearing is determined solely by acoustic coupling. A quantitative analysis of structure-function relationships can both explain the wide range of observed post-operative hearing results and suggest surgical guidelines in order to optimize the post-operative results. (4) In tympanoplasty types I, II and III, the hearing result depends on the efficacy of the reconstructed tympanic membrane, the efficacy of the reconstructed ossicular chain and adequacy of middle-ear aeration. Currently, our knowledge of the mechanics of these three factors is incomplete. The mechanics of mastoidectomy and stapedectomy are also discussed.     

Robert H Herman Memorial Award in Clinical Nutrition Lecture, 1997. Mechanisms causing loss of lean body mass in kidney disease

In most cell types, including resting skeletal muscle fibers, internal pH (pHi) is kept constant at a relatively alkaline level. The high pHi is obtained in spite of a chronic acid load resulting from cellular metabolism and passive influx of protons driven by electrochemical forces. Regulation of pHi depends on continuous activity of membrane transport systems that mediate an outflux of H+ (or bicarbonate influx), whereby the acid load is counterbalanced. The transporters involved in muscle pH regulation at rest are the Na+/H+ exchange system as well as the Na+-dependent and Na+-independent Cl- bicarbonate transport systems. The Na+/H+ exchanger seems to be active at resting pHi levels in skeletal muscle. Therefore, pH homeostasis in skeletal muscle most likely involves an equilibrium between counter-directed H+ fluxes. A minor fraction of H+ release during intense exercise is mediated by the Na+/H+ exchanger. The capacity of this system is increased with training and hypoxia in rat skeletal muscle. The dominant acid extruding system associated with intense exercise is the lactate/H+ co-transporter. It has been demonstrated that the capacity of the lactate/H+ co-transporter of rat skeletal muscle is upregulated with training and chronic electrical stimulation, and that it is reduced upon denervation and hindlimb unweighting. Moreover, athletes can have an elevated lactate/H+ co-transport capacity, whereas the thigh muscle of spinal cord-injured individuals has a lower transport capacity than the one of healthy untrained subjects. Thus, it appears that the capacity of the lactate/H+ transporter is affected by the level of muscle activity in both rats and humans. In addition, the rate of H+ release from muscle may also be influenced by capillarization and local blood flow. Finally the resulting pH displacement during acid accumulation is determined by the cellular buffer capacity, which may also undergo adaptive changes.     

1997 Sir William Refshauge Lecture. Skeletal muscle glucose metabolism during exercise: implications for health and performance

The shear bond strengths of an amalgam (Permite C) and a gallium alloy (Galloy) to dentin, mediated by four dentin adhesives (Super-Bond D-Liner, Super-Bond D-Liner II, Paama 2, and Panavia 21), were investigated. Flat labial dentin surfaces were prepared from bovine lower incisor teeth. A 3 mm-in-diameter area of dentin was bonded according to each manufacturer's directions before placement of Permite C or Galloy. The bonds were stressed in shear at a crosshead speed of 1 mm/min. The mean shear bond strengths were analyzed using one-way ANOVA and Student's t-test, and fracture modes were assessed under X20 magnification and analyzed using Kruskal-Wallis and Mann-Whitney U tests. Scanning electron micrographs were taken of the bond interface of separate samples. The results showed no significant difference among the bond strengths of Super-Bond D-Liner (2.79 MPa, 2.69 MPa), Super-Bond D-Liner II (3.41 MPa, 2.65 MPa), and Paama 2 (0.70 MPa, 0.50 MPa) bonded to Permite C and Galloy (respective values in parentheses); however, Panavia gave a significantly better bond with Permite C (0.42 MPa) than with Galloy (0 MPa). Super-Bond D-Liner and Super-Bond D-Liner II gave stronger bonds than Paama 2 and Panavia with both Permite C and Galloy. For each dentin adhesive, there was no difference in fracture mode between Permite C and Galloy. It was concluded that, since all bond strengths were very low, none of the dentin adhesives tested would enhance the clinical retention of Permite C or Galloy. However, although the use of Paama 2 with Galloy was originally recommended by the manufacturer for dentin sealing purposes, no adhesion was claimed.     

Meningococcal disease: recognition, treatment, and prevention

Meningococcal disease is an infection caused by Neisseria meningitidis, a gram-negative diplococcus that is the leading cause of bacterial meningitis in children and young adults in the United States, with an estimated 2,600 cases reported each year. N. meningitidis infection rates are highest in children 3 to 12 months of age. Four distinct clinical situations are associated with meningococcal infection. The most common is asymptomatic nasopharyngeal colonization. Benign bacteremia is discovered in the absence of classical clinical findings of meningococcemia, but blood cultures are positive for N. meningitidis. Meningitis, the most common pathologic presentation, is associated with fever, headache, and nuchal rigidity. The mortality rate is about 5% in children and 10% to 15% in adults. Meningococcemia, the most severe form of infection, may involve petechial rash, hypotension, and disseminated intravascular coagulation. It is a fulminant condition that can, if untreated, progress from initial symptoms to coma and death in 12 to 48 hours. Spread of these endemic cases can be controlled by administering prophylactic antibiotics to close contacts of patients.     

The federal role in disease prevention and health promotion.

Comments on articles by J. A. Heffernan and G. W. Albee, J. M. McGinnis, W. S. Cohen, and C. Lenfant and M. Schweizer (see PA, Vol 73:1705, 2593 and 1698, respectively) that summarize representative federal efforts to stimulate academia, the private sector, and the community to become more responsive to problems and opportunities in disease prevention and health promotion. The critical elements are in place for a concerted effort to develop and implement disease prevention/health promotion efforts on a nationwide basis, and the implications of successful outcomes of such activities suggests as ever-increasing demand for health behavior scientists and clinicians. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adriana and Luisa Castellucci Award Lecture 1997. Placental pathology in obstetrics: adaptation or failure of the villous tree?

The biochemical and ultracytochemical localization of alkaline phosphatases in permeabilized cells of Saccharomyces cerevisiae 257 has been studied. The treatment with non-ionic surfactant Triton X-100 allows the penetration of the substrate into intact yeast cells and thus provides detailed detection of the enzyme activity in ultracytochemical studies.