Thursday, January 25, 2007

Medical vs. Surgical Tx of Glaucoma

Review of Optometry

In the United States, medicine is the standard first-line treatment. In Europe, surgery often comes first. New studies raise questions about this sequence.

As surgical techniques continue to become safer and more effective in treating glaucoma, the option of surgery first is becoming an earlier consideration for some patients.

This trend of surgery as first-line treatment is already prevalent in Europe, as it is considerably less expensive to perform surgery A gonioscopic view of the anterior pigmented trabecular meshwork, where argon laser trabeculoplasty (ALT) or selective laser trabeculoplasty (SLT) is applied.

Studies have concluded that diurnal variations of IOP appear to be better controlled with surgery than with medicines, yet final control of POAG appeared to be equal between the two groups. If cost factors and IOP factors are removed from the equation, quality of life seems to be better within the medically-treated glaucoma patients compared with the surgically-treated glaucoma patients.

Surgical treatment renders no additional neuroprotection except for the control of IOP. Complication rates appear to be greater with surgical treatment than medical treatment. It appears that the U.S. model—medical treatment followed by laser treatment, then surgical treatment in patients whose glaucoma is either not adequately controlled, who cannot afford or are non-compliant with medicines, or who have presented with side effects from the medicines—fits within good medical practices.

Progressive Myopia and PALs

Role of Parental Myopia in the Progression of Myopia and Its Interaction with Treatment in COMET Children -- Kurtz et al. 48 (2): 562 -- Investigative Ophthalmology & Visual Science

PURPOSE. The present study investigated parental myopia and the effects of wearing progressive-addition (PALs) or single-vision lenses on the progression of myopia in children.

RESULTS. In all children in the PAL group, progression was –2.00 D overall, significantly less than the progression of children wearing single vision lenses. Among children with zero or one myopic parent, progression did not differ significantly between the lens groups.

CONCLUSIONS. Among children with two myopic parents, myopia progression was slower in the group wearing PALs than in those wearing single vision lenses, by a statistically significant but clinically minor amount. Conclusions must be regarded as suggestive.

COMMENTARY: PALs do not appear to help prevent myopic progression in children except in a clinically insignificant manner in children where both parents are myopic.

Tuesday, January 23, 2007

O2Optix Contact Lens Recalled

CIBA VISION CONDUCTS VOLUNTARY TRADE-LEVEL RECALL OF O2OPTIX CONTACT LENSES. CIBA Vision is conducting a voluntary trade-level (not consumer) recall of select lots of spherical O2Optix (lotrafilcon B) contact lenses, distributed primarily in the United States and to a lesser degree in other countries (excluding Japan). The company says it is taking this action after identifying some lenses in the recall lots that did not meet the proper standards for ion permeability, a material characteristic contributing to lens movement on the eye. No other CIBA Vision lens brands are involved in the recall. The company has notified the appropriate health authorities of the recall and is currently notifying customers. A medical assessment, confirmed by experts outside the company, determined that the probability of a serious adverse event associated with use of lenses with reduced ion permeability is remote; however, the lenses may cause persistent discomfort and/or foreign body irritation, and superficial corneal staining may be observed. The medical risk associated with these signs and symptoms is low-to-negligible, and upon lens removal they typically resolve within two to 24 hours. CIBA Vision stresses that no serious adverse events have been attributed to the issue. Although it has begun improving its manufacturing process for the O2Optix lens and has addressed the ion permeability issue, product availability will continue to be affected. In the United States, the company anticipates significant supply constraints and backorders of the lens into the second quarter, with increasing improvements through mid-year.

Thursday, January 18, 2007

Thin Corneas May Produce Worse Visual Field Changes

The Spearman correlation coefficient between intrasubject differences in CCT vs. intrasubject differences in MD and PSD was 0.36 and -0.31, respectively; both were statistically significant. This study suggests that worse visual field changes tend to occur in the eye with the thinner cornea.

SOURCE: Rogers DL, Cantor RN, Catoira Y, et al. Central corneal thickness and visual field loss in fellow eyes of patients with open-angle glaucoma. Am J Ophthalmol 2007;143(1):159-61.