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A syndrome characterized by the triad of uveitis, glaucoma, and hyphema caused by mechanical chafing of the iris due to malposition of an intraocular lens (IOL). Main risk factors include ciliary sulcus placement of a single-piece acrylic IOL and IOL decentration. Definitive treatment involves IOL repositioning or exchange.

Explains how ultra-widefield fundus cameras capture more than 200° of the fundus in a single shot, along with the conditions they are used for, the examination procedure, and key points for interpretation. Covers the features and clinical uses of representative systems such as Optomap and RetCam.

A transient corneal edema that occurs during prolonged physical exertion such as ultramarathons. It is thought to be caused by lactate accumulation in the cornea, presenting with painless progressive blurred vision, and resolves within hours after stopping exercise. Protective eyewear and lubricating eye drops are recommended for prevention.

An imaging device that uses high-frequency ultrasound (35–100 MHz) to obtain high-resolution tomographic images of the anterior segment of the eye. It can visualize structures behind the iris and ciliary body that are difficult to observe optically, and is an essential tool for diagnosing angle-closure glaucoma, anterior segment trauma, tumors, and other conditions.

An examination that uses high-frequency ultrasound (30–50 MHz) to obtain high-resolution tomographic images of the anterior segment. It can visualize structures that are difficult to observe optically, such as the posterior iris and ciliary body, and is useful for diagnosing angle-closure glaucoma, anterior segment trauma, and tumors.

Explains the principles, equipment, surgical technique, mechanism of action, and clinical outcomes of ultrasound cycloplasty (UCP). Covers indications, complications, and comparison with conventional cyclodestructive procedures using high-intensity focused ultrasound (HIFU) for ciliary body coagulation.

Definition of corneal epithelial damage caused by ultraviolet radiation, differences between electric ophthalmia and snow blindness, symptoms, diagnosis using fluorescein staining, and acute treatment and prevention.

A rare complication (UVLASOR) of unexplained visual loss after silicone oil removal following vitreoretinal surgery, with no other apparent cause. Incidence is 1–10%, and tamponade duration is the greatest risk factor.

A condition in which the coronal suture on one side of the skull fuses prematurely, frequently associated with asymmetric orbital deformity, strabismus, anisometropic astigmatism, and amblyopia. Treatment involves endoscopic suturectomy or fronto-orbital advancement.

A rare retinal disease that causes degeneration and atrophy at the photoreceptor level in only one eye. It presents with fundus findings similar to bilateral retinitis pigmentosa (RP), but the contralateral eye remains normal.

Urets-Zavalia syndrome (UZS) is a rare complication after ophthalmic surgery in which the pupil becomes dilated and fixed, unresponsive to light or miotics. It is mainly reported after penetrating keratoplasty, but also occurs after many other ophthalmic surgeries such as cataract surgery, DALK, DSAEK, and phakic intraocular lens implantation. The main pathophysiology is thought to be necrosis of the pupillary sphincter due to iris ischemia.

A technique for noninvasively assessing retinal changes in neurodegenerative diseases using optical coherence tomography (OCT). Research is underway on its application for early diagnosis and disease monitoring of Alzheimer's disease, Parkinson's disease, and others.

A rare genetic disorder characterized by sensorineural hearing loss and retinitis pigmentosa. It follows an autosomal recessive inheritance pattern and is designated as an intractable disease in Japan. It is classified into three clinical subtypes, with progressive visual field constriction and hearing loss as features.

A rare disease causing idiopathic exudative detachment of the choroid, ciliary body, and retina. It is thought to be primarily caused by impaired drainage of intraocular fluid due to scleral abnormalities, and treatments include scleral window surgery and steroid therapy.

A rare phenomenon in which oblique scanning of the probe during ultrasonography of a hypermature cataract falsely depicts the lens equator as a dome-shaped lesion resembling uveal melanoma. Accurate differentiation is important.

Macular edema secondary to uveitis, a major cause of visual impairment. Steroid administration is the mainstay of treatment, but new therapies such as suprachoroidal injection and dexamethasone implant have emerged in recent years.

Chronic uveitis complicating juvenile idiopathic arthritis (JIA). It accounts for up to 47% of pediatric uveitis cases and is a refractory ocular disease that often progresses asymptomatically, leading to visual impairment.

A group of diseases that present with intraocular inflammation similar to uveitis but are not immune-mediated or infectious. They are broadly divided into neoplastic and non-neoplastic types, with intraocular lymphoma being the most common. Early differential diagnosis is crucial for visual function and life prognosis.

A postoperative complication of cataract surgery characterized by the triad of uveitis, glaucoma, and hyphema, caused by mechanical chafing of intraocular tissues by an intraocular lens (IOL). Early diagnosis and surgical intervention are key to preserving visual function.