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Surgical Approaches and Steps
Published in Pradeep Venkatesh, Handbook of Vitreoretinal Surgery, 2023
Tenotomy is the surgical step of incising the tenons capsule [and intermuscular septa] to gain access to the muscle insertion and scleral surface [Figure 9.2]. This is followed by bridling the recti muscles [see section on surgical anatomy], taking precautions to not split the muscle, the muscular arteries, and fibres of the superior and inferior oblique [Figure 9.3]. Thick cotton thread or silk suture could be used to for this purpose. Bridle suture must be about 10 cm in length [after doubling] and is knotted proximally at about 10 mm from the muscle insertion and distally close to the ends of the suture. Knots at about 10 mm from the muscle insertion allow the surgeon to have better control on the muscles, thereby allowing precise globe rotation and preventing sudden slippage [while passing scleral sutures].
Sclera
Published in Mostafa Khalil, Omar Kouli, The Duke Elder Exam of Ophthalmology, 2019
Omar Kouli, Mostafa Khalil, Rizwan Malik
There are three parts to the sclera: Episclera (outermost): Thin vascularized connective tissue anterior to the sclera and posterior to the Tenon capsule.Substantia propria: Made of irregularly arranged type I collagen fibrils.Lamina fusca (innermost): Made of loosely arranged connective tissue and separated from the choroid by the suprachoroidal space.
Scleritis and episcleritis
Published in Gwyn Samuel Williams, Mark Westcott, Carlos Pavesio, Bushra Thajudeen, Practical Uveitis, 2017
Gwyn Samuel Williams, Mark Westcott
The most useful clinical examination that can be performed in clinic is a B-scan ultrasound. This will demonstrate a thickening of the posterior coats of the eye, with a thickness greater than 2 mm considered abnormal. In unilateral disease a comparison can be made with the unaffected eye. An additional textbook giveaway sign is fluid collecting between the sclera and Tenon capsule which results in the famous ‘T sign’ with the optic nerve and fluid forming the stem and arms of the letter ‘T’, respectively (Figure 7.5). The investigations for this are identical again to the above but on top of these, due to the different presentation other causes for choroidal folds and a swollen disc also need to be considered and ruled out, the most important of which is raised intracranial pressure. Other conditions that can mimic posterior scleritis include orbital inflammatory disease, choroidal haemangioma, uveal effusion syndrome, atypical central serous chorioretinopathy and Vogt–Koyanagi–Harada (VKH) syndrome. All of these will have distinctive features on fluorescein angiography, B-scan ultrasound (for instance the lack of a T sign), orbital and even brain MRI imaging that can help us distinguish between them.
Antimicrobial-eluting cement orbital implant: a case report of staged enucleation for infectious panophthalmitis with extraocular extension
Published in Orbit, 2023
Kevin D. Clauss, Ying Chen, Marissa K. Shoji, Thomas E. Johnson, Roger E. Turbin
Two months following the implantation of the drug-eluting cement, the patient returned to Bascom Palmer Eye Institute for follow-up. Upon examination, the conjunctiva was well approximated without signs of infection. The patient underwent removal of the drug-eluting cement and placement of a permanent scleral-wrapped porous polyethylene implant. Intraoperatively, the conjunctiva and Tenons capsules were opened to disclose a socket with minimal inflammation and a freely mobile 19 mm cement ball (Figure 3A). There were two small, <1 mm, lesions on Tenons capsule at the incision site without significant scarring within Tenons capsule (Figure 3B). The cement implant was easily removed using a muscle hook (Figure 3C). A 20 mm scleral-wrapped porous polyethylene implant was placed deep in the socket. The 4–0 silk tagged muscles were easily identified and then attached to the implant using a technique described by Richard Collin,9 where sutures were attached to the sclera and passed into the fornices medially, laterally, and inferiorly. The conjunctiva and Tenons were then closed in a layered fashion.
Sub-Tenon Sustained Controllable Delivery of Dexamethasone for Treating Severe Acute Experimental Uveitis
Published in Ocular Immunology and Inflammation, 2020
Libei Zhao, Xuetao Huang, Manqiang Peng, Qian Tan, Wenxiang Lin, Muhammad Ahmad Khan, Qiongyan Tang, Ding Lin
The described SSCDDS was prepared according to our previous experiment with modification.21 Briefly, after topical application of 0.5% proparacaine hydrochloride for three times, a small closed catheter (0.7 mm×19 mm) with a 24G needle (BD Intima) Closed IV Catheter System, Becton Dickinson Co.) was inserted into tenon capsule in the same manner as sub-tenon injection. Following catheter insertion, the needle was withdrawn, and the catheter was fixed between tenon capsule and sclera. Then, 0.3 ml of 5 mg/ml DXM was trickled into the sub-tenon as initial dosage. Another end of the catheter was combined with an auto-infusion pump (BYZ-810T, BIYANG Corp., Changsha, China) and sustained release of DXM at the rate of 0.1 ml/h for 10 h to the sub-tenon (Figure 1).
Primary replacement for the management of exposed orbital implant
Published in Orbit, 2019
David S. Curragh, Srikandan Kamalarajah, Brendan Lacey, Stephen T. White, Alan A. McNab, George Kalantzis, Peter J. Dolman, Dinesh Selva, Saul N. Rajak
The material of the exposed/removed implant was exchanged with a material of similar type (either porous or non-porous) in 23/33 (70%) of cases. The implant material type was changed (from porous to non-porous or vice versa) in 10/33 (30%) of cases. The replaced median size of the implant was unchanged at 18 mm. In 28/33 (85%) of cases, a more posterior location of implant or opening of posterior tenons capsule was described. Re-exposure occurred in 3/33 patients (9.1%) with an orbital implant. The mean time to re-exposure was 55 ± 77.4 months (3–144 months) in cases of orbital implant, porous or non-porous. In 2/3 (67%) patients, re-exposures occurred in cases of porous implants and in 1/3 (33%) in cases of non-porous implants. Signs of infection were present in 2/3 patients (66%).