From the library
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《英国眼科学杂志》
"Borges’s reaction to his blindness was not anger—he was well beyond anger by now—but stupor, a kind of dazed incomprehension at the inscrutable fate that seemed to have destroyed all possibility of salvation by writing. On February 15, 1955, not long after leaving the clinic, he wrote a short text about Dante’s last days at Ravenna. The dying poet has a dream in which God reveals to him the secret purpose of his life and work. Filled with wonder, Dante learned at last who he was and what he was and blessed his roles, but upon waking he discovers he can no longer recall the secret purpose. In other words, even Dante had not been saved in the end by writing the Divine Comedy; he had been given and had lost a measureless thing, something he could not retrieve or even make out, for the workings of this world are far too complex for the simplicity of man." ( Williamson, Edwin. Borges. A Life. New York: Viking, 2004:324–5)
The metabolic syndrome is defined as two or more of the following: obesity, hypertension, dyslipidaemia, or impaired glucose regulation. The overall prevalence of metabolic syndrome appears to be 10–15%. Non-diabetic people with metabolic syndrome have an increased risk from all causes as well as cardiovascular disease. In a study from Canada there appears to be a relation between cardiorespiratory fitness and mortality in healthy men with the metabolic syndrome. In this study cardiorespiratory fitness provided a strong protective effect against all-cause and cardiovascular disease mortality in both healthy men and men with the metabolic syndrome. ( Arch Intern Med 2004;164:1092–7)
Nitric oxide has been identified as one of the mediators of damage in the so called "axonal death" cascade. In a recent study from London 18 patients with optic neuritis and 14 controls were investigated in a longitudinal prospective study. Plasma phosphorylated neurofilament heavy chain, a surrogate marker of axonal injury, nitric oxide metabolites, and citrulline were measured. In this study, plasma phosphorylated neurofilament heavy chain proved to be a prognostic indicator in patients with optic neuritis. The authors suggest that its monitoring should be considered in the design of neuroprotective treatment strategies. ( J Neurol Neurosurg Psychiatry 2004;75:1178–80)
It is still not clear if chronic excessive exposure to sunlight leads to an increased risk of development of age related maculopathy. In the Beaver Dam Eye Study the 10 year incidence of age related maculopathy was studied. In this cohort few significant relations between environmental exposure to light and the 10 year incidence and progression of age related maculopathy were found. Consistent with results from the baseline and 5 year follow up examinations significant associations were found between extended exposure to summer sun and the 10 year incidence of age related maculopathy and increased retinal pigment injury. The protective effect of wearing a hat and sunglasses to prevent the development of soft indistinct drusen and retinal pigment epithelial depigmentation was demonstrated. ( Arch Ophthalmol 2004;122:750–7)
Probably no more than half the cases of acute infectious conjunctivitis in primary care are related to a bacterial origin. Most general practitioners feel unable to discriminate between a bacterial and viral cause. As a result, more than 80% of such patients receive antibiotics. The cost of this excessive antibiotic treatment is not inconsiderable. In England the cost to the NHS in 1 year is ￡4.7 million. In a cohort study of consecutive patients, an investigation in the Netherlands tried to identify clinical features that would correlate with the presence of bacterial infection. In this study three diagnostic indicators—glued eyes, itch, and a history of conjunctivitis—provide optimal discrimination between patients with and without a positive bacterial culture. The authors suggest that in adult patients with conjunctivitis and these three features ocular antibiotic therapy should be used. ( BMJ 2004;329:206–8)
Visual disturbances following upper eyelid blepharoplasty are relatively common. In a recent retrospective review a group of 146 patients were studied. 5% had subjective visual acuity changes 1 year after upper eyelid blepharoplasty and four of the six patients who had combined upper eyelid blepharoplasty and ptosis surgery were affected. The authors emphasise that if these surgical procedures are performed by plastic surgeons and not ophthalmic plastic surgeons these patients need to be referred postoperatively for ophthalmic re-evaluation and treatment. ( Arch Vis Plast Surg 2004;6:155–7)
Relatively recently a new syndrome has been described as cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASL). This syndrome is an inherited small artery disease related to notch 3 gene mutations on chromosome 19. Although it is a systemic vascular disease its clinical expression has heretofore been thought to be purely neurological and characterised mainly by subcortical infarcts and dementia. A recent study, however, emphasises that retinal findings are relatively common in this syndrome. In this study with fluorescein angiography and funduscopic examination silent retinal abnormalities were seen in a significant number of patients. 22% had nerve fibre loss and 17% had cotton wool spots. The presence of these abnormal retinal findings was not related to the severity of the disorder but may be considered useful clinical signs in diagnosing this genetic vascular disorder. ( J Neurol Neurosurg Psychiatry 2004;75:1058–60)
A significant proportion of patients who have optic neuritis will develop multiple sclerosis. Multiple sclerosis is generally seen as a progressive, debilitating disorder. However, long term studies of patients with multiple sclerosis suggest that many of these patients maintain a relatively normal life. In a population based prevalence cohort study from Minnesota investigators from the Mayo Clinic undertook a quality of life assessment of patients with multiple sclerosis. The majority (77%) were mostly satisfied or delighted with their quality of life at the time of study. The authors emphasise that multiple sclerosis can cause significant disability but most patients continue to have a good quality of life. ( Arch Neurol 2004;61:679–86)
In mammals, caloric restriction delays the onset of age related diseases including cancer, atherosclerosis, and diabetes, and can greatly increase lifespan. The molecular mechanism underlying this effect has not been previously been understood. In a study from Harvard Medical School in rats, investigators have demonstrated the expression of mammalian SIR 2 (SIRT1) in caloric restricted rats as well as in human cells that are treated with serum from these animals. Insulin and insulin-like growth factor 1 (IGF-1) attenuated the response. Thus, caloric restriction appears to extend lifespan by inducing SIRD1 expression and promoting the long term survival of irreplaceable cells. ( Science 2004;305:390–4)
The metabolic syndrome is defined as two or more of the following: obesity, hypertension, dyslipidaemia, or impaired glucose regulation. The overall prevalence of metabolic syndrome appears to be 10–15%. Non-diabetic people with metabolic syndrome have an increased risk from all causes as well as cardiovascular disease. In a study from Canada there appears to be a relation between cardiorespiratory fitness and mortality in healthy men with the metabolic syndrome. In this study cardiorespiratory fitness provided a strong protective effect against all-cause and cardiovascular disease mortality in both healthy men and men with the metabolic syndrome. ( Arch Intern Med 2004;164:1092–7)
Nitric oxide has been identified as one of the mediators of damage in the so called "axonal death" cascade. In a recent study from London 18 patients with optic neuritis and 14 controls were investigated in a longitudinal prospective study. Plasma phosphorylated neurofilament heavy chain, a surrogate marker of axonal injury, nitric oxide metabolites, and citrulline were measured. In this study, plasma phosphorylated neurofilament heavy chain proved to be a prognostic indicator in patients with optic neuritis. The authors suggest that its monitoring should be considered in the design of neuroprotective treatment strategies. ( J Neurol Neurosurg Psychiatry 2004;75:1178–80)
It is still not clear if chronic excessive exposure to sunlight leads to an increased risk of development of age related maculopathy. In the Beaver Dam Eye Study the 10 year incidence of age related maculopathy was studied. In this cohort few significant relations between environmental exposure to light and the 10 year incidence and progression of age related maculopathy were found. Consistent with results from the baseline and 5 year follow up examinations significant associations were found between extended exposure to summer sun and the 10 year incidence of age related maculopathy and increased retinal pigment injury. The protective effect of wearing a hat and sunglasses to prevent the development of soft indistinct drusen and retinal pigment epithelial depigmentation was demonstrated. ( Arch Ophthalmol 2004;122:750–7)
Probably no more than half the cases of acute infectious conjunctivitis in primary care are related to a bacterial origin. Most general practitioners feel unable to discriminate between a bacterial and viral cause. As a result, more than 80% of such patients receive antibiotics. The cost of this excessive antibiotic treatment is not inconsiderable. In England the cost to the NHS in 1 year is ￡4.7 million. In a cohort study of consecutive patients, an investigation in the Netherlands tried to identify clinical features that would correlate with the presence of bacterial infection. In this study three diagnostic indicators—glued eyes, itch, and a history of conjunctivitis—provide optimal discrimination between patients with and without a positive bacterial culture. The authors suggest that in adult patients with conjunctivitis and these three features ocular antibiotic therapy should be used. ( BMJ 2004;329:206–8)
Visual disturbances following upper eyelid blepharoplasty are relatively common. In a recent retrospective review a group of 146 patients were studied. 5% had subjective visual acuity changes 1 year after upper eyelid blepharoplasty and four of the six patients who had combined upper eyelid blepharoplasty and ptosis surgery were affected. The authors emphasise that if these surgical procedures are performed by plastic surgeons and not ophthalmic plastic surgeons these patients need to be referred postoperatively for ophthalmic re-evaluation and treatment. ( Arch Vis Plast Surg 2004;6:155–7)
Relatively recently a new syndrome has been described as cerebral autosomal dominant arteriopathy with subcortical infarcts and leucoencephalopathy (CADASL). This syndrome is an inherited small artery disease related to notch 3 gene mutations on chromosome 19. Although it is a systemic vascular disease its clinical expression has heretofore been thought to be purely neurological and characterised mainly by subcortical infarcts and dementia. A recent study, however, emphasises that retinal findings are relatively common in this syndrome. In this study with fluorescein angiography and funduscopic examination silent retinal abnormalities were seen in a significant number of patients. 22% had nerve fibre loss and 17% had cotton wool spots. The presence of these abnormal retinal findings was not related to the severity of the disorder but may be considered useful clinical signs in diagnosing this genetic vascular disorder. ( J Neurol Neurosurg Psychiatry 2004;75:1058–60)
A significant proportion of patients who have optic neuritis will develop multiple sclerosis. Multiple sclerosis is generally seen as a progressive, debilitating disorder. However, long term studies of patients with multiple sclerosis suggest that many of these patients maintain a relatively normal life. In a population based prevalence cohort study from Minnesota investigators from the Mayo Clinic undertook a quality of life assessment of patients with multiple sclerosis. The majority (77%) were mostly satisfied or delighted with their quality of life at the time of study. The authors emphasise that multiple sclerosis can cause significant disability but most patients continue to have a good quality of life. ( Arch Neurol 2004;61:679–86)
In mammals, caloric restriction delays the onset of age related diseases including cancer, atherosclerosis, and diabetes, and can greatly increase lifespan. The molecular mechanism underlying this effect has not been previously been understood. In a study from Harvard Medical School in rats, investigators have demonstrated the expression of mammalian SIR 2 (SIRT1) in caloric restricted rats as well as in human cells that are treated with serum from these animals. Insulin and insulin-like growth factor 1 (IGF-1) attenuated the response. Thus, caloric restriction appears to extend lifespan by inducing SIRD1 expression and promoting the long term survival of irreplaceable cells. ( Science 2004;305:390–4)