Uveitis Glaucoma Hyphema Syndrome (UGH)

Introduction

In 1977 Ellingson described a syndrome that included uveitis, glaucoma, and hyphema in patients with a specific anterior chamber (AC) intraocular lens (IOL) [1].   While initially the syndrome was associated with this particular IOL, it became clear that the syndrome was associated with other AC and later with posterior chamber (PC) IOLs.   The syndrome eventually became known as the UGH (pronounced liked “ug” in ugly) syndrome to emphasize the three most important features of the syndrome. An extension of the syndrome, “UGH plus syndrome” refers to patients that have vitreous hemorrhage in addition to uveitis, glaucoma, and hyphema.  

UGH syndrome is related to uveal tissue coming in contact with an IOL (usually the haptics).  The hyphema or vitreous hemorrhage comes from episodic injury to vessels in the iris, ciliary body or angle. The glaucoma is secondary to the uveitis, treatment of the uveitis, pigment dispersion, hemorrhage, or direct injury to angle structures.

When AC IOLs were commonly placed, UGH syndrome was a common indication for IOL exchange.  As PC IOLs began to dominate our practice, UGH syndrome became less common, but still important. PC IOLs in the sulcus seem to be at most risk for UGH syndrome, especially if they are loose or are single piece acrylic (SPA) IOLs with wide square haptics [2].  Even PC IOLs positioned completely in the capsular bag can cause UGH syndrome if the zonules are loose and the resultant pseudophakodonesis irritates the iris.

UGH syndrome

While technically UGH syndrome includes all three entities (uveitis, glaucoma, and hyphema) it is common to use the term “UGH” even when only one or two of the three are present (for example “the patient had UGH syndrome without hyphema”). An irritating IOL is the essential element now to the diagnosis of UGH. As the IOL is the defining feature of UGH syndrome, it would not be consistent to propose UGH syndrome in a phakic or aphakic patient.

The diagnosis of UGH syndrome is not always simple. The differential diagnosis includes many diverse conditions including TASS, endophthalmitis, idiopathic uveitis, retained lens material, neovascularization Angle or the wound (Swan Syndrome).   Slit lamp examination is the most important tool to establish the diagnosis. Identifying areas of iris injury, typically due to a haptic, through direct or trans-illumination lighting techniques can help make the diagnosis of UGH syndrome. Loose IOLs (pseudophacodonesis) can often be seen moving during the slit lamp examination and may be the critical finding to make the diagnosis, particularly with PC IOLs in the bag. Gonioscopy is important to search for residual lens material and to visualize haptic position especially with AC IOLs. High frequency ultrasound of the anterior segment allows imaging of PC IOLs including haptic position and iris contact.   Ultrasound can also be useful to search for residual lens material behind the iris which can mimic UGH syndrome. Optical coherence tomography (OCT) of the anterior segment can be helpful to image IOL malposition and angle structures, but is less useful for locating structures behind the iris than is ultrasound. 

Anterior Chamber IOLS

The classic UGH syndrome is related to an AC IOL. The AC IOL’s association with UGH syndrome and with pseudophakic bullous keratopathy, clouded the reputation of AC IOLs. However, modern AC IOLs are effective.  Wagoner’s classic paper found no difference in overall complications between AC IOL and sutured posterior chamber IOLs [3].  A too large or too small AC IOL can irritate the iris and lead to UGH syndrome.  The most important issue is proper sizing and placement of the AC IOL. The AC IOLs come in several sizes depending on the manufacturer. In general, you should add 1 mm to the “white to white” measurement of the corneal diameter to establish the optimum length for the AC IOL along a particular axis. Typically a caliper is used to measure the distance from one point of the limbus to another point directly across. The point of the limbus where the cornea just turns “white” is the target for the so called “white to white” measurement. When scarring and pannus is present, this can be a difficult measurement. Some of the devices to measure and calculate the IOL power preoperatively will also acquire the “white to white” measurement for you. An AC IOL which is not long enough will tilt and rotate, which can cause UGH syndrome. An AC IOL which is too long can erode into the angle and cause pain and UGH syndrome. 

Treatment of UGH syndrome associated with AC IOLs depends on the severity of the condition.  Mild uveitis alone, associated with an AC IOL, can be treated with chronic anti-inflammatory therapy. When the AC IOL leads to a fuller spectrum of UGH syndrome, the IOL is typically exchanged for either an aphakic contact lens or a posterior chamber IOL.   Occasionally repair of the iris or reposition of the AC IOL will stabilize the IOL and eliminate the UGH.    Glued IOL or Iris Suturing of a posterior IOL can be effective strategies to replace an IOL with no capsular support.  Another strategy which is difficult in the US at present is placement of an iris clipped IOL to avoid angle and iris posterior leaf contact. 

Sulcus IOL

As AC IOL placement becomes less common, it seems that sulcus based IOLs are the most common cause of UGH syndrome in our current practice. An IOL in the sulcus can shift, rotate and/or tilt and irritate uveal tissue to cause UGH syndrome. The risk for UGH syndrome increases, when the haptic length is too small or when the haptics (or even the optic) have a square edge which can irritate the iris. Chang outlined the issues of placing a sulcus IOL and suggested that very few of the existing PC IOLs are well suited for sulcus placement [2].  The perfect sulcus IOL would have long thin angled haptics and a large optic made of a non-silicone material with a smooth rounded anterior edge.

Single Piece Acrylic (SPA) IOLs can cause of UGH if one or both of the haptics are (inadvertently) placed in the sulcus. The large square haptics of the SPA can irritate the posterior leaf of the iris causing inflammation, pigment disruption, and either vitreous or anterior chamber hemorrhage Gonioscopy can be useful in determining if one of the haptics is anterior to the capsule. Transillumination of the iris can be very useful to find areas where the square haptic has dispersed pigment off of the posterior iris.  Here is a case where a patient presented with a convincing story for amaurosis fugax  only to discover the patient had UGH plus syndrome with vitreous hemorrhage from a misplaced SPA haptic that episodically injured iris blood vessels.

The treatment of UGH syndrome associated with sulcus based PC IOL depends on the severity and the amount of residual capsule. If a patient has only mild inflammation, you could consider chronic anti-inflammatory treatment and observation. If the patient has only ocular hypertension from pigment dispersion, you could consider topical aqueous suppression and observation. However, when UGH syndrome is more severe and particularly when it includes vitreous hemorrhage, an IOL exchange or repositioning should be considered.   Rarely the IOL can be repositioned by capsular remnants into a more stable position.  One approach is to replace the posterior IOL with and AC IOL to eliminate any IOL contact with the posterior leaf of the iris.   If the IOL is poorly suited for the sulcus (eg too small or a SPA IOL) then it could be exchanged for another sulcus IOL.  If one of the SPA haptics is out of the bag, then it can be repositioned into the bag or simply amputated. If the anterior segment is so large that no lens is really adequate for the sulcus, you could consider suturing a 3-piece IOL to the iris, suturing to the sclera, or tucking the haptics into glued scleral pockets. Sometimes the best approach is to simply remove the IOL and use aphakic spectacles or contact lenses.

PC IOL in the bag

A more recent cause of UGH syndrome comes when an IOL completely encased in the capsular bag irritates the iris or ciliary body.  The typical cause is weakened zonules (often from pseudoexfoliation) that allows pseudophacodonesis which can irritate uveal tissue.  As our patients are living longer following surgery, subluxed IOL/bag complexes are becoming more common.

The treatment for this condition depends on the severity of UGH syndrome. If the inflammation is mild and the patient older or frail, it might be best to simply treat with anti-inflammatory medicine and observe. However in most cases, if the IOL is loose enough to cause UGH syndrome, it is probably at risk for complete luxation with time.

One important examination technique is to place the patient back into a supine position and see if the IOL, although loose, remains horizontal. If the IOL goes vertical when the patient is lying back, it may make more sense to have a vitreoretinal surgeon remove the IOL as it will most likely be entangled in vitreous. However if the IOL remains horizontal, then an anterior approach is often successful. The typical surgical strategy is to either suture the existing IOL or exchange it for another.

If the IOL is a SPA and not suited for the sulcus, then you have 2 options. One option is to simply remove the IOL/bag complex and replace a sutured PC IOL, glued PC IOL, AC IOL, or aphakic contact lens. The other option is to suture the entire complex to the sclera as we have described [4] also here.  If the IOL is a 3-piece IOL, you may be able to remove the bag (with vitrectomy or other instruments) and use the existing IOL. The existing IOL could be sutured to the iris, sutured to the sclera, or tucked into scleral glued pockets. Often a Soemmering’s ring with residual lens material is present and care must be taken to not allow this material to fall posteriorly. 

Summary

UGH and UGH plus syndrome continues to be an important condition to discover and treat. Even though we have shifted from using AC to PC IOLs, we still see the syndrome. The most common cause now is probably from sulcus placed IOLs (either on purpose or inadvertently) but even IOLs placed completely in the bag can cause UGH if loose. If the symptoms are mild, medical treatment and observation is possible, but typically the IOL is secured or exchanged to eliminate the uveal irritation leading to the syndrome.

References

1. Ellingson FT. Complications with the Choyce Mark VIII Anterior Chamber Lens Implant. Journal - American Intra-Ocular Implant Society. 1977; 3(3-4):199-201

2. Chang DF, Masket S, Miller KM, Braga-Mele R, Little BC, Mamalis N, Oetting TA, Packer M; ASCRS Cataract Clinical Committee. Complications of sulcus placement of single-piece acrylic intraocular lenses: recommendations for backup IOL implantation following posterior capsule rupture. J Cataract Refract Surg. 2009 Aug;35(8):1445-58. doi: 10.1016/j.jcrs.2009.04.027. PubMed PMID: 19631134

3. Wagoner MD, Cox TA, Ariyasu RG, Jacobs DS, Karp CL; American Academy of Ophthalmology. Intraocular lens implantation in the absence of capsular support: a report by the American Academy of Ophthalmology. Ophthalmology 2003 Apr;110(4):840-59

4. Oetting TA(1), Tsui JY, Szeto AT. Sliding internal knot technique for late in-the-bag intraocular lens decentration. J Cataract Refract Surg. 2011 May;37(5):810-3.