ORBIS--training nurses worldwide in ophthalmic care

The unique nature of the ORBIS teaching mission is reflected in many arenas. The ORBIS organization recognizes that the nurse's role is critical to achieving their mission of preventing blindness through education, hence the emphasis on nurse education. The roles of the head nurse, nurse educator, staff nurses, and the biomedical engineering department are discussed briefly with emphasis on the needs assessment and the different programs offered to meet the identified needs.

The MRI appearance of the optic nerve sheath following fenestration for benign intracranial hypertension

Optic nerve fenestration is carried out in cases of severe benign intracranial hypertension. This study aimed to monitor the optic nerve sheath appearances and orbital changes that occur following this procedure. The eight patients were all female with an average age of 37.3 years and a range of 20-58 years. The duration of symptoms was 2-6 years. Symptoms included headaches, diplopia and visual obscurations. Examination revealed severe papilledema. All investigations, including MRI, biochemical and immunological tests, were negative. Patients had fenestration of a 2 mm x 3 mm segment of the medial aspect of the optic nerve sheath. Imaging was obtained with a 1 T MRI machine using a head coil. Coronal, axial and sagittal 3 mm contiguous sections using STIR sequences with TR 4900 ms, IT 150 ms and TE 60 ms were obtained. Five patients showed clinical improvement. The post-operative MRI findings in four of these included a decreased volume of cerebrospinal fluid (CSF) around the optic nerve sheaths and a localized collection of fluid within the orbit. There were no MRI changes in the three patients with no clinical improvement. Decreased CSF volume around the optic nerve and a fluid collection within the orbit may indicate a favorable outcome in optic nerve fenestration.

Computed tomography and positron emission tomography in the pre-operative staging of oesophageal carcinoma

Because patients with carcinoma of the oesophagus usually present with advanced disease and surgery has a high mortality with cure in less than 10% of patients, pre-operative staging to select appropriate patients is necessary. Computed tomography (CT) plays an important role in staging but has well recognized limitations. Positron emission tomography (PET) which provides physiological information may therefore be a better alternative.

OBJECTIVE

To compare the findings of CT and positron emission tomography (PET) with 2-[18fluorine]-fluoro-2-deoxy-D-glucose (FDG) in the pre-operative staging of oesophageal carcinoma.

MATERIALS AND METHODS

Twenty-five patients with biopsy proven oesophageal cancer had pre-operative staging using CT and FDG-PET. The studies were read independently and full histological confirmation was obtained in 19 patients. Four parameters were studied: the primary tumour, peri-oesophageal lymph nodes, liver metastases and left gastric lymph nodes.

RESULTS

PET visualized all primary tumours; CT missed one. CT identified 4/8 patients with involved peri-oesophageal nodes and PET 3/8. CT identified 5/9 patients with left gastric adenopathy and PET 1/9. PET visualized a liver metastasis missed on CT and appeared to be better in assessing residual tumour. PET did identify distant metastases not seen on CT in seven patients.

CONCLUSIONS

The two techniques are both effective in showing the primary tumour and about equally sensitive in the demonstration of peri-oesophageal nodes. PET is probably more sensitive than CT for the detection of distant metastases.

Androgen-dependent modulation of calbindin-D28K in hypothalamic tissue during prenatal development

We examined the influence of androgens on fetal medial basal hypothalamic and preoptic area (MBH-POA) calbindin-D28K levels (via Western analysis) by treating pregnant rats with testosterone or flutamide, (an androgen receptor blocker). MBH-POA calbindin-D28K levels were significantly decreased in flutamide-treated male fetuses, whereas, MBH-POA calbindin-D28K levels were significantly increased in testosterone-treated female fetuses compared to controls. These results suggest that MBH-POA calbindin-D28K is modulated during prenatal development by androgens.

Inequality in infant morbidity: causes and consequences in England in the 1990s. ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood

STUDY OBJECTIVE

To examine the effect of deprivation, crowding, maternal smoking, and breast feeding on morbidity from wheeze and diarrhoea in the first six months after birth.

DESIGN

A geographically located population survey using maternal responses on self completion questionnaires.

SETTING

The three health districts of Bristol.

SUBJECTS

8501 infants from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC) in which all women expecting a baby between April 1991 and December 1992 in Bristol were invited to participate.

MAIN OUTCOME MEASURES

The prevalence and severity of wheeze at six months after birth. The prevalence of diarrhoea and the duration of the worst bout at six months after birth.

RESULTS

Logistic regression analyses using a conceptual hierarchical framework showed that wheeze was significantly more likely to be reported for infants if they lived in rented accommodation (OR = 1.20, 95% CI = 1.04, 1.39), if they lived in crowded housing conditions (OR = 1.26, 95% CI = 1.06, 1.49), if they were one of a number of siblings (OR = 1.78, 95% CI = 1.52, 2.07), and if their mothers smoked (OR = 1.38, 95% CI = 1.21, 1.58). They were significantly less likely to have wheeze if they were breast fed (OR = 0.68, 95% CI = 0.59, 0.79). Each of these factors was independently related to the prevalence of wheeze. For infants with wheeze those who were breast fed for three or more months were significantly less likely to have three or more episodes in the first six months after birth (OR = 0.76, 95% CI = 0.58, 0.99). A higher prevalence of diarrhoea in infancy was associated with living in rented accommodation (OR = 1.25, 95% CI = 1.10, 1.41) and lower maternal education (OR = 0.76, 95% CI = 0.69, 0.84) and a lower prevalence with breast feeding (OR = 0.42, 95% CI = 0.37, 0.48). An episode of diarrhoea was significantly less likely to last for six or more days if an infant lived in mortgaged accommodation (OR = 1.34 95% CI = 1.03, 1.75) and was breast fed for three or more months (OR = 1.34 95% CI = 1.03, 1.75).

CONCLUSION

Deprivation was associated with heightened morbidity from common conditions such as wheeze and diarrhoea for this geographical cohort of infants in England in the 1990s. Results supported evidence suggesting that breast feeding is protective against such conditions and is particularly associated with reduced severity and duration. Implications for future research and policy are discussed.

Heterogeneity among cardiac ischemic and anginal responses to exercise, mental stress, and daily life

The objectives of this study were to compare and contrast indicators of ischemia in a well-characterized group of 196 patients with coronary artery disease, documented angiographically or by verified history of myocardial infarction, and a positive exercise test result. Myocardial ischemia occurs frequently in response to everyday stressors in patients with coronary artery disease. The Psychophysiological Interventions in Myocardial Ischemia study provides a unique opportunity to study neuroendocrine and psychological manifestations of ischemia. Patients with exercise-induced ischemia underwent exercise radionuclide ventriculography and electrocardiographic monitoring and 2 laboratory mental stressors (Speech and Stroop) after being withdrawn from cardiac medications. In addition, 48-hour ambulatory electrocardiograms were recorded during routine daily activities. Patients with a history of angina within the past 3 months reported angina during the bicycle or treadmill test with a much higher frequency than patients without such an anginal history (77% vs 26%). Ejection fraction (EF) responses to the Stroop test were abnormal in 48% of patients with an abnormal EF response to the Speech task, versus 17% in patients with a normal EF response (p <0.01). Seventy-six percent of patients had an abnormal EF response to bicycle exercise. Three indicators of ischemia (ST-segment depression, wall motion abnormality, and EF response) were compared during the same laboratory stressor and across different types of stress tests. Presence of the 3 indicators was only moderately associated during exercise, and only weak or nonsignificant associations occurred among the presence of the 3 ischemic markers during mental stress. Occurrence of the same ischemic markers was moderately associated between the 2 mental stress tasks, but few associations were found between the occurrence of the same ischemic marker during exercise and mental stress. There is a marked heterogeneity of responses to psychological and exercise stress testing using electrocardiography, ambulatory electrocardiography, or radionuclide criteria for ischemia during stress. The heterogeneity may be related to differences in the magnitude or types of physiologic responses provoked and to differences in the sensitivity and specificity of the different tests used to identify ischemia.

Calretinin and calbindin-D28K in male rats during postnatal development

Calcium-binding proteins play potentially important roles in neurogenesis and neuroprotective mechanism(s). Some evidence exists that brain calbindin-D28K (CALB) is regulated by androgens. In the present study, calretinin (CALRET) and CALB patterns were determined by Western analysis in the medial basal hypothalamus (MBH) from male rats along with assaying plasma testosterone levels during postnatal development. Testosterone levels were very low in 7-, 10-, and 30-day-old animals (approximately 0.5 ng/mL), increased in a stair-step fashion to peak levels at 90 days (approximately 3.8 ng/mL), then declined with increasing age to very low levels at 300 days of age (approximately 0.3 ng/mL). At 7 and 10 days, MBH CALRET and CALB levels were low; however, at Day 30 a significant twofold increased was observed. Thereafter, in 60-, 120-, 180-, and 300-day-old animals MBH CALRET and CALB levels were, in general, comparable to 30-day-old values. These findings suggest that there is not a clear correspondence between the androgen status in male rats and the calcium-binding proteins (CALRET & CALB) expressed in the MBH. Therefore, it appears that brain CALRET and CALB are regulated in a developmental fashion with significant increases in expression occurring around the 4th postnatal week.

The Psychophysiological Investigations of Myocardial Ischemia (PIMI) study: objective, methods, and variability of measures

OBJECTIVE

This study evaluated physiological, neuroendocrine, and psychological status and functioning of patients with coronary artery disease in order to clarify their role in the expression of symptoms during myocardial ischemia (MI), and to establish repeatability of responses to mental stress. Design and methods of the study are presented.

METHODS

One hundred ninety-six coronary artery disease patients were examined during physical and mental stress tests in four hospitals. Eligibility criteria included narrowing of at least 50% in the diameter of at least one major coronary artery or verified history of myocardial infarction, and evidence of ischemia on an exercise treadmill test. Psychological, biochemical, and autonomic function data were obtained before, during, and after exposure to mental and exercise stressors during 2 or 3 half-days of testing. Ventricular function was assessed by radionuclide ventriculography, and daily ischemia by ambulatory electrocardiography. Sixty patients returned for a short-term mental stress repeatability study. Twenty-nine individuals presumed to be free of coronary disease were also examined to establish reference values for cardiac responses to mental stress.

RESULTS

Study participants were 41 to 80 years of age; 83 (42%) had a history of MI, 6 (3%) of congestive heart failure, and 163 (83%) of chest pain; 170 (87%) were men; and 90 (46%) had ischemia accompanied by angina during exercise treadmill testing. Ischemia during ambulatory monitoring was found in 35 of 90 (39%) patients with and 48 of 106 (45%) patients without angina during exercise-provoked ischemia. Intraobserver variability of ejection fraction changes during bicycle exercise and two mental stress tests (Speech and Stroop) was good (kappa = 1.0, .90, and .76, respectively; percent agreement = 100, 97.5, and 93.8%, respectively). Variability of assessed wall motion abnormalities during bicycle exercise was better (kappa, agreement = 85%) than during Speech or Stroop kappa and .57, percent agreement = 70% and 82.5%, respectively).

CONCLUSIONS

Study design, quality control data, and baseline characteristics of patients enrolled for a clinical study of symptomatic and asymptomatic myocardial ischemia are described. Lower repeatability of reading wall motion abnormalities during mental stress than during exercise may be due to smaller effects on wall motion and lack of an indicator for peak mental stress.

Modern surgery for global cataract blindness: preliminary considerations

Unoperated cataract in the developing world remains ophthalmology's major unsolved problem. Recent developments have brought into question the assumptions of those who have thought that extracapsular surgery with implantation of a posterior chamber intraocular lens is an unrealistic approach to the treatment of global cataract blindness. High-quality 1-piece posterior chamber intraocular lenses are being manufactured locally for approximately $10 each. Most ophthalmologists can be trained to perform extracapsular surgery in a 1-month course. This process is particularly effective if outstanding local surgeons receive intensive training to become instructors. While the incidence and treatment of posterior capsule opacification requires further study, the development of a low-cost YAG laser may be a solution. Imaginative ways to recover costs will need to be developed if the staggering prevalence of cataract blindness is to be effectively addressed. The improved result of modern surgery may make patients more willing to pay for their operation.

Alternative medical treatment for endometriosis

Although a limited number of drugs make up the mainstay of treatment of endometriosis, many alternative medications have been used in an attempt to improve efficacy. Some have been rigorously evaluated and are of proven benefit, while others show promise in preliminary trials or in animal models. Proper methods of evaluating medical therapy and outcomes are essential. This chapter provides a review of new medical therapies for the treatment of endometriosis and their evaluation.

Predictability of excimer laser treatment of myopia and astigmatism by the VISX Twenty-Twenty. Melbourne Excimer Laser Group

BACKGROUND

To determine the predictability of excimer laser photorefractive keratectomy (PRK) to correct myopia, astigmatism, or both between -1.00 and -19.00 diopters (D).

SETTING

Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.

METHODS

This study comprised 1218 consecutive eyes treated with a VISX Twenty-Twenty excimer laser and followed prospectively for 12 months. Low myopia was treated with one ablation zone (6.0 mm), high myopia with two ablation zones (5.0 and 6.0 mm), and extreme myopia with three ablation zones (4.5, 5.0, and 6.0 mm). Maximum spherical treatment was 15.00 D at the corneal plane. Data were analyzed to determine the predictability of the postoperative outcomes by preoperative refraction.

RESULTS

Nine hundred eighty eyes (80.5%) were available for the 12 month follow-up. The predictability of refraction and uncorrected and best corrected visual acuities progressively decreased with increasing myopia, although a comparable percentage of spherical correction was achieved at each diopter of myopia. The likelihood of losing lines of best corrected visual acuity and corneal haze increased with increasing myopia.

CONCLUSION

These data can be used to counsel patients of likely outcomes of excimer laser PRK to correct myopia.

Hydroxyaluminosilicates and acute aluminium toxicity in fish

The essentiality of silicon in biology might be explained in the terms of its chemistry with aluminium. In a previous study we demonstrated the elimination of acute aluminium toxicity in fish by silicon. We suggested that the reaction of silicic acid with aluminium to form hydroxyaluminosilicates reduced the biological availability, and hence toxicity, of aluminium. Though assumed in a burgeoning number of studies and contended in others this detoxification mechanism has remained unproven. Herein we have tested the toxicity of hydroxyaluminosilicates in fish and in doing so we have provided evidence which strongly supports a role for hydroxyaluminiosilicates in the elimination of acute aluminium toxicity in fish by silicon.Copyright 1997 Academic Press Limited Copyright 1997 Academic Press Limited

The relationship between condition-specific morbidity, social support and material deprivation in pregnancy and early motherhood. ALSPAC Survey Team. Avon Longitudinal Study of Pregnancy and Childhood

Poorer health has been consistently associated with both low levels of social support and material deprivation. It has been proposed that social support constitutes a causal link between health and deprivation such that those with lower socio-economic status have poorer health because their lack of social support makes them more vulnerable to disease. This assumption was tested in this study for women moving from pregnancy to early motherhood. The sample of 9208 women was drawn from the Avon Longitudinal Study of Pregnancy and Childhood (ALSPAC). Health status was measured by self-report of morbidity for three contrasting conditions: backache, depression and urinary infection. Data were collected by self-completion questionnaire at eight weeks prepartum and at eight weeks postpartum. The sample was divided into four groups for each condition on the basis of identification of the condition (1) on both occasions, (2) on neither occasion, (3) at eight weeks prepartum only, and (4) at eight weeks postpartum only. Chi-square tests were used to measure the association between presence or absence of a condition as defined above, material deprivation and low social support. Responses on an eight item social support questionnaire tapping emotional, instrumental and communal aspects of perceived social support were compared between these groups for each condition. Results showed significant associations, in late pregnancy and early motherhood, between poorer health and both material deprivation and low social support for two of the three conditions, depression and urinary infection. Changes in levels of perceived social support occurred as a consequence of motherhood; the percentage of women perceiving their partner to be supportive decreased as did the percentage of those who felt that their family or friends would help with financial difficulties; in contrast, the percentage of those perceiving that other mothers/neighbours offered support increased from late pregnancy to early motherhood. The extent and direction of such change was consistently associated with the presence or absence of depression, but not with backache or urinary infection. When mental health "improved", in that depression was present pre- but not postpartum, the percentage feeling supported increased and vice versa. This pattern was in evidence across all items of social support. It was concluded that perceived social support was unlikely in itself to constitute a causal link between poorer health and lower socio-economic status. In this context the relationship between social support and depression requires further consideration, particularly the extent to which they constitute component parts of a more general feeling of emotional well-being, a construct which is, in its turn, in need of further articulation in relation to health outcomes.

The new medical marketplace: physicians' views

The transformation of the medical marketplace has major implications for the physician workforce. Findings are reported here from national surveys of physicians, hospitals, health maintenance organizations (HMOs), preferred provider organizations (PPOs), and medical group practices conducted in 1995 to measure the impact of those changes. Physicians in higher HMO penetration states were more likely to report serious problems with several aspects of medical practice and patient care and were more likely to perceived oversupply in their specialty areas and changes in their practice arrangements. Some divergence is noted in views of supply between physicians and those that employ them. The majority of physicians would still recommend medicine and their specialty as a career.

Pain scoring as a formal pain assessment tool

This article describes the introduction of subjective pain scoring as a pain assessment tool to the surgical unit of a district general hospital. The author highlights the advantages, and explains the actions taken to overcome the problems of changing practice through the introduction of a formal pain assessment tool.

Quantification of latent tissue reservoirs and total body viral load in HIV-1 infection

The capacity of HIV-1 to establish latent infection of CD4+ T cells may allow viral persistence despite immune responses and antiretroviral therapy. Measurements of infectious virus and viral RNA in plasma and of infectious virus, viral DNA and viral messenger RNA species in infected cells all suggest that HIV-1 replication continues throughout the course of infection. Uncertainty remains over what fraction of CD4+ T cells are infected and whether there are latent reservoirs for the virus. We show here that during the asymptomatic phase of infection there is an extremely low total body load of latently infected resting CD4+ T cells with replication-competent integrated provirus (<10(7) cells). The most prevalent form of HIV-1 DNA in resting and activated CD4+ T cells is a full-length, linear, unintegrated form that is not replication competent. The infection progresses even though at any given time in the lymphoid tissues integrated HIV-1 DNA is present in only a minute fraction of the susceptible populations, including resting and activated CD4+ T cells and macrophages.

Blepharospasm and hemifacial spasm. Randomized trial to determine the most appropriate location for botulinum toxin injections

PURPOSE

The purpose of the study is to analyze the effectiveness and side effects of botulinum toxin using four different treatment site applications to determine the most successful treatment regime with the least side effects.

METHODS

In a prospective trial, 92 patients (50 blepharospasm and 42 hemifacial spasm) were assigned randomly to 1 of 4 different treatment groups (standard [S], brow [B], inner orbital [IO], or outer orbital [OO]). Each treatment group had a different pattern of injection sites in the orbicularis. A total of 285 treatments were given, and the mean follow-up time was 16.4 months.

RESULTS

In the blepharospasm group, patients assigned to the standard group had a significantly longer duration of effect than for those in the brow, inner orbital, and outer orbital groups (8.1 weeks compared with 4.5, 4.2, and 3.1 weeks, respectively; P < 0.001). In the hemifacial spasm group, patients in the outer orbital group had significantly shorter duration of effect than those in standard, brow, or inner orbital group (7.2 weeks compared with 12.6, 12.8 and 10.4 weeks, respectively; P < 0.001). The four major complications of botulinum toxin treatment were epiphora, ocular irritation, ptosis, and diplopia. The inner orbital treatment produced significantly more episodes of ptosis (13% of treatments). However, the standard treatment produced the most epiphora and ocular irritation (18% of treatments).

CONCLUSIONS

The position of the injection sites around the orbicularis influences the effectiveness and side effects of botulinum toxin treatment for patients with blepharospasm and hemifacial spasm. The further the treatment is away from the eyelid margin, the lower the risk of ocular side effects. The standard treatment produces the longest duration of effect in the blepharospasm group but with the most transient ocular irritation and epiphora. In the hemifacial spasm group, the brow treatment has an equally long duration of effect as that of the standard treatment with fewer side effects.

Late recurrences and the necessity for long-term follow-up in corneal and conjunctival intraepithelial neoplasia

PURPOSE

The purpose of the study was to elucidate the natural history of corneal-conjunctival intraepithelial neoplasia (CIN) and suggest treatment and follow-up guidelines.

METHODS

The records of all histologically proven cases of CIN at the Royal Victorian Eye and Ear Hospital between 1979 and 1994 were reviewed.

RESULTS

Seventy-nine eyes of 76 patients had a pathologic diagnosis of CIN and were observed for up to 15 years. The lesion recurred in 31 eyes (39%) overall. There was no statistical difference shown in the likelihood of recurrence based on histologic classification. Complete excision was attempted in each case. In 18 eyes, dysplastic cells were evident at the excision margin. Ten (56%) of these tumors recurred, compared to a 33% recurrence rate in completely excised lesions. The time to the first recurrence ranged from 33.0 days to 11.5 years between the first and second surgeries, with 11 lesions recurring after more than 4 years. Incompletely excised lesions reappeared more rapidly (average, 2.5 years) than did those with clear surgical margins (average, 3.8 years). Seven cases progressed to invasive squamous cell carcinoma and four cases led to blindness or removal of the eye.

CONCLUSIONS

This study suggests that excision margin at the time of surgery is the most important factor in predicting recurrence. The slow growth of the recurrent lesions combined with the ever-present malignant potential leads the authors to suggest that all patients with a history of CIN warrant annual follow-up for the remainder of their lives.