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Vitreoretinal Surgery in Rare Conditions
Published in Pradeep Venkatesh, Handbook of Vitreoretinal Surgery, 2023
Chronic diseases of the retina and choroid such as age-related macular degeneration [ARMD], diabetic retinopathy, and chronic non-infectious uveitis are extremely challenging to manage in the long term. This is largely because delivery of drugs to the posterior segment of the eye has to overcome numerous anatomical and physiological barriers to achieve an effective and sustained concentration of the drug within the vitreous cavity, retina, and choroid. While intravitreal injections have been effective, repeated breach of the ocular coat increases the risk of endophthalmitis, traumatic cataract, increased IOP, intraocular haemorrhage, and retinal detachment. In addition, there are an added economic burden and time crunch with repeated intravitreal injections. In this background, the most appropriate solution seems to reside in the availability of safe and effective sustained drug delivery devices. These devices should be biologically and chemically inert, should be devoid of immediate and late procedure-related complications, must not impede optical clarity of the vitreous, must not obstruct the central visual field, must have an ease of surgical insertion and removal [or be biodegradable], and must be affordable. An ideal drug delivery device fulfilling all of these criteria is yet to become commercially available. An ideal solution for port-side sustained release drug delivery could be an inflatable drug reservoir [see section of port delivery system].
Basic Principles of Laser
Published in Anita Prasad, Laser Techniques in Ophthalmology, 2022
Lenses are classified into anterior and posterior segment lenses. Anterior segment lenses are used to visualize lens capsule, IOL, and ocular angle.Posterior segment lenses are used to visualize vitreous and retina. They are further classified as: Concave CL (negative lens) – creates an upright, virtual fundal imageConvex lens (positive lens) – creates an inverted, real fundal imageMirror lens
Corneal Disorders
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Darren S. J. Ting, Rashmi Deshmukh, Daniel S. W. Ting, Marcus Ang
Ophthalmology is a heavily imaging-centric specialty that utilizes advanced imaging technologies to assist the diagnosis and management of a wide range of ocular diseases. The widespread availability of ophthalmic images has made ophthalmology one of the best specialties for harnessing the power of AI, particularly those that employ DL-based algorithms. While the majority of ophthalmology-related AI research previously focused on the screening and diagnosis of posterior-segment diseases (e.g., diabetic retinopathy, age-related macular degeneration, and glaucoma), AI research is now starting to gain traction in the realm of corneal diseases, particularly for keratoconus, refractive surgery, and IK.134
Tamoxifen related chorioretinal structural changes
Published in Cutaneous and Ocular Toxicology, 2023
İnci Elif Erbahçeci Timur, Vehbi Açıkgöz, Nagihan Uğurlu, Bülent Yalçın, Mehmet Ali Nahit Şendur, Mutlu Hızal, Halil Kara
Although tamoxifen-related retinal toxicity is rare, central serous chorioretinopathy (CSCR) [9], pacyhchoroid pigment epitheliopathy (PPE) [10,11], and alterations in choroidal thickness [12] were recently reported as tamoxifen-related impairments. PPE and CSCR are pachychoroid spectrum disorders, which have been defined in 2013 as subfoveal choroidal thickness of 300 μm or more [13]. The choroid has the highest amount of vascular tissue of the human body and supplies the posterior segment of the eye, which consists of choriocapillaris, the outer layer with large blood vessels known as Haller’s layer and the inner layer with small and medium vessels known as Sattler’s layer. Measuring choroidal thickness using enhanced depth imaging (EDI) with spectral domain optical coherence tomography (SD-OCT), identifying the vascular layer and stroma of the choroid by the binarisation method is used to determine the pathophysiology of retinochoroidal conditions.
Paraneoplastic Pemphigus Associated with Bilateral Corneal Perforations in Follicular Dendritic Cell Sarcoma
Published in Ocular Immunology and Inflammation, 2022
Nandini Venkateswaran, Olga Klavdianou, Georgios Kondylis, Ioannis Kosmidis, Sotiria Palioura
A 73-year-old Greek woman presented to the ophthalmology clinic with complaints of decreased vision in both eyes. Her ocular history was notable for uncomplicated clear corneal cataract surgery with implantation of posterior chamber intraocular lenses (PCIOL) 2 years prior. On presentation, her visual acuity was hand motion vision in both eyes. There was superior and inferior forniceal foreshortening in both eyes with symblepharon formation (Figure 1A, C). Notably, corneal perforations were noted in both corneas with iris plugging (Figure 1B, D). The anterior chambers were shallow but formed bilaterally and the PCIOLs were in stable position. Ultrasonography of the posterior segment showed mild vitreous debris OU with no choroidal or retinal detachments.
Recurrent Episodes with Serous Retinal Detachment and Anterior Uveitis in a Patient Using Nivolumab (Anti -PD-1 Antibody) Therapy: A case report and literature review
Published in Seminars in Ophthalmology, 2021
Busra Yilmaz Tugan, Berna Ozkan, Ozlem Sonmez
At the initial examination, his best-corrected visual acuity (BCVA) was counting fingers in both eyes, with an intraocular pressure of 13 mm Hg in the right eye and 12 mm Hg in the left eye. Slit-lamp examination revealed no abnormal findings or inflammation in the anterior segment of both eyes. Posterior segment evaluation showed serous retinal detachment, including the whole macula and inferior retina in both eyes. Optical coherence tomography (OCT, Heidelberg Engineering GmbH, Heidelberg, Germany) confirmed the presence of serous detachment with hyporeflective subretinal fluid in the macula (Figure 1). On Fluorescein Angiography (FA, Heidelberg Engineering GmbH, Heidelberg, Germany), no vascular abnormalities, filling defects, blockage, and leakage or staining were observed (Figure 1). The patient was treated with 48 mg oral methylprednisolone and subretinal fluid resolved one week after treatment in the right eye and two weeks after treatment in the left eye (Figure 2). BCVA was 20/20 in both eyes at the first month of treatment. Methylprednisolone was tapered after the first month and stopped at the end of the second month. The patient was followed monthly.