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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.
Diabetic Retinopathy
Published in Jahangir Moini, Matthew Adams, Anthony LoGalbo, Complications of Diabetes Mellitus, 2022
Jahangir Moini, Matthew Adams, Anthony LoGalbo
A “full” PRP includes 1,200 or more 500 µm burns that use argon green or a blue/green laser, which are separated by one-half burn width. Contracture of fibrovascular tissue occurs, so treatment can be followed by additional vitreous hemorrhage, vitreoretinal traction, combined tractional-rhegmatogenous retinal detachment, and tractional retinal detachment. Also, the contraction of fibrovascular tissue and additional traction can cause recurring vitreous hemorrhages. The adverse effects of scatter PRP include decreased color and night vision, reduced contrast sensitivity, and decreased peripheral vision. A patient can lose one or two lines of visual acuity or see “glares.” There are transient adverse effects such as loss of accommodation and corneal sensitivity, as well as photopsias. A PRP procedure can precipitate or worsen macular edema. The use of more peripheral laser placement may be able to stop progression of proliferative diabetic retinopathy and preserve the biggest central visual field. When the horizontal meridians (the pathways of long ciliary vessels and nerves) are spared, accommodation and corneal innervation are protected. When needed, extensive treatment is performed in retinal areas where vision loss is not as noticeable or is related to less morbidity. The nasal and superior retina receive extensive treatment last because they correspond to essential temporal and inferior peripheral vision. Extra care is taken to avoid foveal photocoagulation, especially when image-inverting contact lenses are used.
The Special Sense Organs and Their Disorders
Published in Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss, Understanding Medical Terms, 2020
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss
Disorders of light perception include photopsia, photophthalmia, photophobia, nyctalopia, and photonosus. Ocular emergencies include chemical burns and corneal trauma from abrasion or foreign bodies.
Multiple Evanescent White Dot Syndrome Following Adenovirus Vector-Based COVID-19 Vaccine (Covishield)
Published in Ocular Immunology and Inflammation, 2023
Abhilasha Baharani, Raja Rami Reddy
MEWDS following vaccination has been reported with rabies, human papilloma virus, hepatitis A, hepatitis B, meningococcal, Yellow fever, and influenza vaccines.6Table 1 summarizes all 15 cases of MEWDS following COVID-19 vaccination,7–15 including the present case: 88.6% patients were otherwise healthy, mostly young to middle aged (mean 34.06 years, median 28 years, range 15–71 years) and 73.3% were women. Ten patients (66.6%) received BNT162b2/Pfizer-BioNTech vaccine, 2 patients (13.3%) received mRNA-1273/Moderna vaccine and one patient (6.6%) each received inactivated vaccine (Sinovac Coronavac), MVC protein subunit vaccine and viral vector vaccine Covishield (present case). Symptoms appeared after the second dose in 9 patients (60%), after the first dose in 4 patients (26.7%). One patient developed symptoms after the booster dose and one patient manifested symptoms after the first as well as second doses. The average time for onset of symptoms was 9.2 days (median 7 days, range 1–30 days) after vaccination. The mean presenting visual acuity was 20/65 (median 20/32, range 20/20 to 20/400). The most common symptoms were photopsias (80%), blurred vision (73.3%) and scotomata (40%). Spontaneous resolution was seen in 11 out of 15 cases (73.3%) over an average of 5.7 weeks (median 4 weeks, range 2–16 weeks). Three patients (20%) were treated with oral corticosteroids and 1 patient (6.6%) was put on topical steroid eyedrops.
Combination Treatment with Rituximab and Bortezomib in a Patient with Non-Paraneoplastic Autoimmune Retinopathy
Published in Ocular Immunology and Inflammation, 2020
Matthew D. Benson, David J. A. Plemel, Elaine Yacyshyn, Irwindeep Sandhu, Ian M. MacDonald, Chad F. Baker
Autoimmune retinopathy (AIR) is a rare inflammatory condition that causes bilateral outer retinal degeneration and results in significant visual impairment. Patients typically present with reduced visual acuity, paracentral scotomas, photopsias, photophobia, dyschromatopsia, and night-blindness. Initially, the fundi often appear unremarkable. Given this discrepancy between clinical symptoms and signs, a strong index of suspicion is required in order to prompt additional testing.1 Visual field, full-field electroretinography (ffERG), optical coherence tomography (OCT), and the presence of anti-retinal antibodies are all useful in supporting a diagnosis of autoimmune retinopathy.2 Visual field testing demonstrating central or paracentral scotomas or peripheral constriction and OCT evidence of outer retinal degeneration provide diagnostic support for AIR.1 While there are no pathognomonic changes in the ffERG, reduced cone- and rod-driven responses and an electronegative ERG have all been described in AIR.1
MFSD8 gene mutations; evidence for phenotypic heterogeneity
Published in Ophthalmic Genetics, 2019
Davood Zare-Abdollahi, Ata Bushehri, Afagh Alavi, Alireza Dehghani, Mohammadreza Mousavi-Mirkala, Jalil Effati, Seyed Ali Mohammad Miratashi, Mohammad Dehani, Payman Jamali, Hamid Reza Khorram Khorshid
Five Iranian patients (four males and one female; three from Ardakan and two from Shahroud) were offspring of consanguineous marriages (Figure 1a & b). The range of age at onset of earliest symptoms was 15–20 years. Initial manifestations in all patients of families A and B were decreased sharpness of vision followed by increased sensitivity to light (photophobia). Development of visual field impairment and night blindness (nyctalopia) was emerged at the age of 30–34 and 38–40, respectively. All patients reported the presence of perceived flashes of light (photopsia). A searching nystagmus was spotted. Posterior subcapsular lens opacities were utterly present in all affected members, one undergone subsequent cataract surgery. In terms of BCVA, the impairment was more severe in family A than in B; BCVA of patients of family A consisted of two with light perception (LP) and one with no light perception (NLP) bilaterally, whereas in patients of family B, the figures were quite similar as the right eye was 20/1,000 equivalent to counting finger 4 feet (CF4ʹ) and the left eye was 20/2000 (CF2ʹ). With regard to refractive errors, the result of the examination of family A appeared to be plano since slight hypermetropic refractive errors were present in the participants of family B. They also underwent the confrontational visual field and color vision testing that indicates sparing of the peripheral 5 ̊ to 10 ̊ and total achromatism, respectively, while the mentioned tests were not applicable for family B. None of the cases had the capacity of visual fixation on an accommodative target held at 40 cm.