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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
Gonioscopy is the examination of the angle of the anterior chamber with a gonioscope (lens) or a contact prism lens and beam illumination from a slit lamp. This procedure is used to detect retinal or optic nerve disease. Applanation tonometry is used to measure intraocular pressure in millimeters of mercury (mmHg). If diagnosis is still in doubt, provocative procedures such as a water drinking test, darkroom test, or mydriatic tests are employed. Other diagnostic procedures may include gross visual fields and basic motor exam, fluorescent angioscopy (examination of the capillary vessels), slit lamp examination, keratometry, ophthalmodynamometry, needle oculo-electromyography, electro-oculography (EOG), and retinoscopy.
Introduction
Published in Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza, Computer-Aided Glaucoma Diagnosis System, 2020
Arwa Ahmed Gasm Elseid, Alnazier Osman Mohammed Hamza
Gonioscopy is a test for examining the angle where the cornea meets the iris, using a special mirrored device to gently touch the surface of the eye. Whether this angle is open or closed can show the doctor what type of glaucoma there is and how severe it may be.
Membrane removal in proliferative vitreoretinopathy
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
Michael S L.e.e, Gary W Abrams
The surgical eye must be assessed carefully and undergo a complete examination. Although the cornea does not usually present a problem, it must be sufficiently clear to permit surgery. The iris should be evaluated for rubeosis, synechiae, and pupillary dilation. Eyes with rubeosis have a poorer prognosis. Preoperative knowledge that the pupil does not dilate adequately, requiring pupil stretching or breaking of synechiae, will facilitate surgical planning. The eye should be evaluated for glaucoma and undergo gonioscopy. These eyes are more likely to develop postoperative intraocular pressure (IOP) problems, and they should be managed accordingly to minimize pressure elevation. If the eye is hypotonus, it should be examined carefully for anterior PVR and traction on the ciliary processes.
Current Concepts of the Uveitis-Glaucoma-Hyphema (UGH) Syndrome
Published in Current Eye Research, 2023
Meera S. Ramakrishnan, Kenneth J. Wald
Clinical examination findings are often underappreciated. Iris transillumination along the length of the haptic is specific for iris to haptic chafing- other types of transillumination are not (Figure 5). Thereafter, the examination requires a widely dilated pupil for evaluation. Assessment of haptic position is often best by viewing the eye tangentially by rotating the slit lamp (Figure 6). Gonioscopy can be helpful in some cases. Clinical determination of haptic position can be difficult and diagnostic imaging of this area of the eye is limited. Anterior segment OCT does not image posterior to the iris, but can be used to screen for IOL-iris contact or IOL tilt prior to proceeding with UBM.24 Ultrasound biomicroscopy (UBM) has limited depth of field (5 mm) and resolution of 50 microns, requires a water-bath immersion with direct contact to the eye, and longer acquisition times, but can be used to evaluate IOL position relative to the posterior iris. In a case series by Piette et al. UBM identified PCIOL haptic contact with the iris pigment epithelium, pars plicata, or angle recess near a filtering bleb ostium, and one case of ACIOL haptic erosion into the ciliary body.25 Intraoperatively, the area can be analyzed with an endoscope, however the use of this technique in vitreoretinal surgery is rare. The author has worked on a prototype retractable intraocular mirror to be used during vitreous surgery for this purpose.
Controversies in Pediatric Angle Surgery and Secondary Surgical Treatment
Published in Seminars in Ophthalmology, 2023
Alexander K. Young, Deborah K. Vanderveen
Other new minimally invasive glaucoma surgery devices were designed to allow surgeons to perform nearly 360 degrees of treatment from a single incision using an ab interno approach. The OMNI Surgical System (Sight Sciences, Menlo Park, California, USA) utilizes a prolene catheter threaded through the trabecular meshwork. It can also perform viscocanalostomy, as the catheter contains a lumen that will inject viscoelastic into the canal and collector channels when retracted.16 Requirements to perform this technique are similar to traditional goniotomy, including a clear cornea to visualize the angle via gonioscopy. This approach for primary angle surgery is beginning to be described in the literature, with promising results.17 Additionally, gonioscopy-assisted transluminal trabeculotomy is another option that spares conjunctiva and performs a 360 goniotomy.18
Therapeutic Vitrectomy in the Management of Uveitis: Opportunities and Challenges
Published in Seminars in Ophthalmology, 2022
Nidhi Mahendra Vithalani, Soumyava Basu
Pre-operative evaluation and management: The main components of preoperative evaluation include the following: Clinical and laboratory evaluation for diagnosis of uveitis: This includes anatomical classification of uveitis based on primary focus of inflammation, grading of anterior chamber and vitreous haze, ocular imaging to determine extent and pattern of disease activity, and targeted laboratory tests for the etiological diagnosis of uveitis. The laboratory tests should be aimed at ruling out infectious etiology and any underlying systemic disease.47 These steps are essential, as they determine the initial medical management, and accordingly the need for therapeutic PPV and post-operative treatment.Structural evaluation of the eye: This is critical for achieving the therapeutic goals and minimising post-operative complications. It includes confirming adequate media clarity for intraoperative visualisation of fundus, intraocular pressure (IOP) measurement to rule out hypotony, ultrasound biomicroscopy (for assessment of the ciliary body), and B-scan ultrasonography in eyes with dense vitritis (for retinal detachment, fibrous bands and/or choroidal mass lesions). A preoperative gonioscopy, even in eyes with normal IOP, is advisable to evaluate the risk of postoperative rise of IOP.