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Visual Fields in Neuro-Ophthalmology
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
The field of vision is all that is visible at the same time during steady fixation of gaze. The normal visual field extends to approximately 90° temporally to central fixation, 50° superiorly and nasally, and 60° inferiorly.1 The field of vision maps onto the retina. The electrical signals from the retina are transmitted via the anterior visual pathways to the visual cortex. From there the conscious visual percept is constructed by the brain. A lesion at any point in the anterior visual pathway can produce a visual field defect.2,3
Artificial Intelligence and Hospital Automation
Published in Salvatore Volpe, Health Informatics, 2022
Another important factor in successfully integrating AI is in choosing its area of use. In our current capacity, AI is a more natural fit with certain clinical applications than others. A particularly good match for AI is the detection of diabetic retinopathy, the most common cause of vision impairment and blindness in adults who suffer from diabetes. Diabetic retinopathy occurs when high blood sugar levels damage blood vessels in light-sensitive retinal tissue in the back of the eye. Early detection is critical for managing this condition, but since half of diabetic patients do not see an eye doctor annually, many are not properly screened for diabetic retinopathy, according to Malvina Eydelman, MD, of the FDA Center for Devices and Radiological Health.
Photothermal Lasers
Published in Anita Prasad, Laser Techniques in Ophthalmology, 2022
Retinal holes and tears are often encountered during routine fundoscopy and pose a risk for retinal detachment. A symptomatic retinal tear presents with a sudden onset of flashing lights (photopsia), floaters, blurred vision, or visual field loss, due to vitreous haemorrhage or retinal detachment.
A review of risk factors for retinal vein occlusions
Published in Expert Review of Cardiovascular Therapy, 2022
Marie Ørskov, Henrik Vorum, Torben Bjerregaard Larsen, Nanna Vestergaard, Gregory Y. H. Lip, Toke Bek, Flemming Skjøth
Glaucoma and arterial hypertension influences the pressure gradients associated with the eye, by changing the intraocular pressure or the intraluminal pressure [60–64]. The eye will act like a pressure chamber around the pressure sensitive retinal veins, defined as a starling resistor. If the ocular perfusion pressure approach zero and the intraocular pressure exceeds the pressure in the retinal vein it will make the vein susceptible to thrombus initiation [15,16,21]. The retinal arteries and veins run in proximity in the lamina cribrosa and arterio-venous crossings. Different mechanisms may result in a retinal vein occlusion. The pulsating retinal arteries, the intraocular pressure, or the cerebrospinal fluid around the lamina cribrosa may cause turbulence in the vulnerable retinal vein [18–21]. Furthermore, the retinal arteries may change the biochemical environment around the vein [17,22].
Systemic quinolones and risk of retinal detachment I: analysis of data from the US FDA adverse event reporting system
Published in Expert Opinion on Drug Safety, 2022
Mohamed Kadry Taher, Abdallah Alami, Christopher A. Gravel, Derek Tsui, Lise M. Bjerre, Franco Momoli, Donald Mattison, Daniel Krewski
Retinal detachment (RD) is a condition involving the separation of the retinal layer of the eye from the underlying tissues, which may lead to complete loss of vision in the affected eye if not managed immediately [13,14]. This separation takes one of two forms: the more common rhegmatogenous type or the less common exudative type [13,14]. The annual incidence of RD ranges from 5–14 cases per 100,000 population based on results from studies conducted in the US, Japan, Finland, Sweden and Croatia [14–16]. Safety concerns have been raised regarding the possibility of a damaging effect of the quinolone class on the connective tissues in the eye [17], similar to their confirmed effect on the connective tissues in the tendons [4,18,19]. These concerns were heightened by reports on quinolone-associated retinal detachment [20], retinal hemorrhage [18], macular degeneration [21], corneal perforation [22] and optic neuropathy [23]. Three recent studies reported a possible association of quinolone antibiotics with RD risk [14,24,25]. Other epidemiologic studies reported conflicting results on the association of quinolones with risk of RD [26–34].
Ocular Complications of Intravesicular BCG Treatment for Bladder Carcinoma
Published in Ocular Immunology and Inflammation, 2022
Osman Melih Ceylan, Ali Hakan Durukan, Yusuf Uysal, Gokhan Ozge, Deniz Dogan, Ugur Bozlar
BCG has been proved to be superior over chemotherapy in reducing recurrence rates of the bladder cancer.6 Lamm et al. reported 2.9% incidence of high fever (>39°C), 1.0% major hematuria, 0.9% granulomatous prostatitis, 0.7% granulomatous pneumonitis/hepatitis, 0.5% arthritis or arthralgia, 0.4% epididymo-orchitis, 0.4% sepsis, 0.3% urethral obstruction, 0.2% bladder contracture, 0.1% renal abscess, and 0.1% cytopenia in a study of more than 1,200 patients who received BCG immunotherapy.7 Rare complications such as conjunctivitis, keratitis, sterile corneal dissolution, uveitis, endophthalmitis, and autoimmune retinitis have been reported in previous reports.8–11 Cugati S et al.9 reported a case of choroidal tubercle with tractional retinal detachment who responded well to ATT treatment. In our patient, two mechanisms might be responsible for the retinal detachment. There is a serous component due to choroidal tubercle and a tractional component due to ERM. Main reason for the detachment is serous component and we think that traction due to ERM is a comorbidity. Therefore, PPV was performed in addition to ATT treatment. However, few reports also reported penile involvement following intravesical BCG immunotherapy similar to our study.12