			Home About us Contact

Visual Acuity Loss (visual + acuity_loss)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

4424: Visual acuity loss with healthy ageing: can it be reversed by wavefront laser?

ACTA OPHTHALMOLOGICA, Issue 2010
D ELLIOTT
Purpose To consider what levels of "super acuity" might be achieved by the correction of ocular aberrations in older patients by wavefront corrected ophthalmic surgery. Note that when comparing visual acuity (VA) of older patients with VA in the young, the average optimal monocular visual acuity of a young subject is about 6/4 (decimal VA 1.50) and not the often quoted ,normal' figure of 20/20 (6/6 or 1.0 decimal). Methods Studies that attempted to isolate the cause(s) of deterioration in visual function with age in normal, healthy eyes were reviewed. Results The majority of studies suggest that the deterioration in visual function with age is primarily due to changes within the neural system rather than optical factors. In addition, several studies have shown increases in ocular aberrations with age, but this is only found when comparisons are made across age groups with fixed pupil sizes. When natural pupil sizes are considered, there is no change in aberrations with age because of age-related pupillary miosis Conclusion There appears to be little scope for ocular aberration correction to be used to counteract the loss of vision with age. Reduced vision in patients with cataract is primarily due to increased forward light scatter, and aberrations play a minor role in reducing vision. Intra-ocular lenses (IOLs) should be designed to keep ocular aberrations at a minimum after cataract surgery, but given that vision loss with age appears to be primarily due to neural changes, there seems little scope for IOLs to improve on the vision of phakic subjects under natural pupil conditions. [source]

Safety of Minimally Invasive Pituitary Surgery (MIPS) Compared with a Traditional Approach

THE LARYNGOSCOPE, Issue 11 2004
David R. White MD
Introduction: Transsphenoidal hypophysectomy is becoming progressively less invasive. Recent endoscopic techniques avoid nasal or intraoral incisions, use of nasal speculums, and nasal packing. Several case series of endoscopic endonasal pituitary surgery have been reported, but relatively little data exists comparing complication rates to more traditional approaches. We compare the complications of our first 50 cases of endoscopic, minimally invasive pituitary surgery (MIPS) to our last 50 sublabial transseptal (SLTS) procedures. Study Design: Retrospective case control study. Methods: Fifty consecutive MIPS procedures and 50 consecutive SLTS procedures were reviewed retrospectively. Complication rates were analyzed and compared. Results: Total complications per patient (P = .005), postoperative epistaxis (P = .031), lip anesthesia (P = .013), and deviated septum (P = .028) occurred more often in the SLTS group. No significant difference was seen in cerebrospinal fluid leak, meningitis, ophthalmoplegia, visual acuity loss, diabetes insipidus, intracranial hemorrhage, or death. In the MIPS group, length of stay (P < .001), use of lumbar drainage (P = .007), and nasal packing (P < .001) were also significantly reduced. Conclusions: Endoscopic endonasal pituitary surgery provides improved complication rates when compared with SLTS approaches. In addition, we note advantages of the MIPS approach, including reduced length of hospital stay and decreased use of lumbar drainage and nasal packing. [source]

Choroidal neovascularization associated with cancer-associated retinopathy

ACTA OPHTHALMOLOGICA, Issue 5 2010
Giuseppe Querques
Abstract. Purpose:, To report an unusual association between cancer-associated retinopathy (CAR) associated with invasive thymoma and choriodal neovascularization (CNV), treated by photodynamic theraphy (PDT). Methods:, A 39-year-old man affected with thymoma and paraneoplastic syndrome (myasthenia gravis and diarrhoea) was observed between October 1997 and September 2007. The patient developed progressive visual dysfunction including bilateral visual acuity loss and concentric constriction of visual fields. Ophthalmological, immunological and systemic examinations were performed. Immunological evaluations included an assessment of antibody activity by indirect immunohistochemistry on sectioned rhesus monkey eye, and Western blot reactions upon an extract of pig retina. Results:, Fundus ophthalmoscopy and fluorescein angiography revealed retinal vessel attenuation and retinal pigment epithelium degeneration. Electroretinogram suggested both rod and cone dysfunction. Indirect immunohistochemistry identified antibody activity within the photoreceptor outer segments. Western blots on the retina revealed that most of the patient's antibody activity was focused upon a retinal protein antigen approximating 145 kD. These findings share the commonalities of size and retinal distribution of the interphotoreceptor retinoid-binding protein (IRBP), a recognized autoantigen. The surgically resected mediastinal tumour was diagnosed as invasive thymoma. No other malignancy has since been found throughout nearly 10 years of follow-up. In March 2006, the patient developed a subfoveal CNV in his left eye, which was treated by PDT. Conclusion:, We describe the third case of paraneoplastic retinopathy associated with invasive thymoma. This is the first example of CAR involving autoantibodies reactive with a retinal protein having the characteristics of the IRBP, and is also the first complicated by CNV treated by PDT. [source]

Multivitamin-mineral supplementation and age-related cataract.

ACTA OPHTHALMOLOGICA, Issue 2008
The Italian-American controlled clinical trial
Purpose To evaluate if a multivitamin-mineral supplement at RDI dosage can prevent incidence and progression of age-related cataract. Methods Randomized, double blind, single centre clinical trial. 1020 participants of Italian descent living in Parma, 55 to 75 years old, were assigned to placebo or to a daily tablet of Centrum. Lens status was assessed at baseline and at yearly follow-up visits by lens photography.Primary outcome was a prespecified increase from baseline in N, C, or PSC opacity grades or cataract surgery. Secondary outcomes were increase in type-specific opacity grades, cataract surgery, and visual acuity loss > 15 letters. Results After an average follow-up of 9 +- 2.4 years there was a decrease in total lens events in participants assigned to Centrum (HR 0.82, 95% CI 0.68-0.98, P = 0.03). Nuclear events were significantly less common (HR 0.66, 95% CI 0.50-0.88, P = 0.004) and PSC events significantly more common (HR 2.00, 95% CI 1.35-2.98, P =< 0.001) in participants taking Centrum. No statistically significant treatment effects were seen for cortical opacities, moderate visual acuity loss, or cataract surgery. Conclusion Lens events were less common in participants who took Centrum, but treatment had opposite effects on the development or progression of N and PSC opacities. This and the absence of effect on a functional outcome does not allow us to recommend the use of RDI nutritional supplement to affect the risk of cataract development (Ophthalmology 115;599,2008). [source]