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February 2011 February 2013 Refractive/astigmatism Figure 2. Dilated eye showing well placed toric IOL. Note alignment marks on peripheral IOL. Source(all): Christopher Hodge, Clinical Research Coordinator with Vision Eye Institute case fine-tuning is required,��� Dr. Lawless said. Dr. Doane said what a patient wants often plays a key role in astigmatism management practices. ���Essentially it comes down to the patient���s desire to not wear glasses or to correct the astigmatic refractive error by nonsurgical means, which is typically with glasses post-operatively,��� Dr. Doane said. ���Roughly 30% of eyes could benefit from surgical intervention for astigmatism, but in my experience the older the patient, the more often the patient opts for glasses as the solution.��� If this is not the case, Dr. Doane said he would then decide whether a corneal procedure or toric intraocular lens is the solution. Screening patients Dr. Doane said he uses a variety of factors when determining whether a patient is a good candidate for limbal relaxing incisions. ���Obtaining IOLMaster keratometry readings, corneal topography, pachymetry, and slit lamp examination provides me with the data to decide if LRIs would be advised and if they could be done safely,��� he said. Meanwhile, Dr. Lawless said the first thing to consider when screening patients is whether the ocular surface is healthy. ���This requires a tear film break-up time and assessment of the tear film meniscus, and a Schirmer���s test when in doubt,��� he said. ���It also requires a slit lamp inspection of the meibomian glands and lid margins because the ocular surface contributes to a good tear film, not just tear volume.��� He said if a problem exists, it must be dealt with both pre-op and post-op. ���As a routine, apart from the slit lamp inspection and the tests as noted above, I perform autokeratometry and IOLMaster, and if there is more than 1 D of corneal astigmatism on either of the above measurements, I then perform corneal topography, generally with the Pentacam [Oculus, Lynnwood, Wash.],��� he said. Managing ocular surface disease before treatment Dr. Lawless offered some tips for managing ocular surface disease, most notably the value of being able to detect and diagnose specific conditions. ���If it is low tear production, deal with this with plugs and lubricants,��� he said. ���If it is meibomian inflammation, deal with this with lid scrubs, topical corticosteroids, and sometimes a combination of the above.��� He also said being able to give an explanation is very helpful for patients because when they understand what is going on, they will appreciate the time and effort put into their treatment. Dr. Doane stressed the importance of getting some ocular surface diseases under control before proceeding. ���If a patient has lid diseases such as acne rosacea or dry eye, I would suggest either getting this under control or advise a toric IOL instead of incisional corneal surgery,��� Dr. Doane said. How asymmetric astigmatism factors in Patients who have some asymmetric astigmatism may need to be addressed differently. Dr. Doane said if patients with asymmetric astigmatism want astigmatism correction, it���s not usually a big issue because this occurs rather often. ���On the other hand, irregular corneal astigmatism can not reliably be remedied with incisional corneal surgery or a toric IOL, so this would need to be understood by the pa- EW FEATURE 59 tient,��� he said. ���If significant, the patient likely has been using a rigid contact lens technology and may need to continue this after cataract surgery.��� Dr. Lawless said he talks to his patients who have irregular corneal astigmatism that they want corrected to discuss what the disease is. ���It may be induced by trauma, uncommon diseases such as pellucid or Terrien���s marginal degeneration, or more commonly from form fruste or clinically apparent keratoconus,��� he said. The severity of the irregular astigmatism can vary, Dr. Lawless said, so the best treatment option would depend on specific cases. ���The irregular astigmatism can be subtle, in which case it can be managed with toric intraocular lenses or corneal incisional surgery,��� he said. ���Or it may be more advanced, in which case it is better dealt with in its own right if possible rather than managed by IOL surgery.��� EW Editors��� note: Dr. Doane has financial interests with Carl Zeiss Meditec. Dr. Lawless has financial interests with Alcon (Fort Worth, Texas). Contact information Doane: jdoane@discovervision.com Lawless: Michael.lawless@visioneyeinstitute.com.au Poll size: 221 EyeWorld Monthly Pulse EyeWorld Monthly Pulse is a reader survey on trends and patterns for the practicing ophthalmologist. Each month we send a four question online survey covering different topics so our readers can see how they compare to our survey. If you would like to join the current 1,000+ physicians who take a minute a month to share their views, please send us an email and we will add your name. Email daniela@eyeworld.org and put EW Pulse in the subject line; that���s all it takes. Copyright EyeWorld 2013