July 2018


Reporting from the 2018 BRASCRS annual meeting

Reporting from the BRASCRS annual
meeting, May 16–19
São Paulo, Brazil

View videos from the 2018 BRASCRS: EWrePlay.org

Amar Agarwal, MD, reviews a video of a glued IOL in the eye of a patient with Marfan syndrome.

View videos from the 2018 BRASCRS: EWrePlay.org

Bruna Ventura, MD, discusses a technique involving partial haptic amputation for lens subluxation.

View videos from the 2018 BRASCRS: EWrePlay.org

Douglas Koch, MD, discusses the nuances of the double-needle technique for scleral IOL fixation.

Challenges in ocular surface and infections

Marian Macsai, MD, Glenview, Illinois, presented on chronic blepharitis and meibomitis. Why is blepharitis/meibomitis important? Dr. Macsai said this is the most common complaint in comprehensive practice and the most common source for postoperative infections. It can be a possible source of MRSA, and meibomian gland dysfunction leads to changes in meibum quality and quantity that can cause evaporative dry eye and ocular surface disruption, leading to dry eye symptoms.
Blepharitis may be anterior or posterior and involves eyelid inflammation, Dr. Macsai noted. Anterior blepharitis is rarely seen, but posterior blepharitis may involve meibomian glands and result in papillary hypertrophy of the tarsal conjunctiva and/or corneal punctate epitheliopathy. 
To diagnose meibomitis, Dr. Macsai said to express the meibomian glands with pressure. The role of the meibum is to create the refractive surface and stabilize the tear film. If it’s abnormal, it could cause rapid tear breakup time and corneal disease. 
These problems could be a source of endophthalmitis, Dr. Macsai said. She added that blepharitis/meibomitis may have symptoms similar to those of dry eye, including burning, irritation, redness, and decreased or fluctuating vision.  
Dr. Macsai suggested using lipid layer analysis with tear film interferometry and meibography. She also mentioned several in-office treatments that can be used: LipiFlow (Johnson & Johnson Vision, Santa Ana, California), BlephEx (Franklin, Tennessee), and MiBo Thermoflo (Mibo Medical Group, Dallas). LipiFlow uses heat and thermal pulsations from both sides of the lids. BlephEx includes small disposable tips and cleans the lid margins. It can be done by technicians. MiBo Thermoflo applies anterior heat to the eye in a series of three treatments, as opposed to heat and thermal pulsations from both sides of the lids. 
Dr. Macsai highlighted the value of using eyelash shampoo. She mentioned a number of other tips for these patients, including using ofloxacin ointment, intense pulsed light therapy, topical azithromycin, and omega-3s. She also noted that Demodex is present in 50% of patients and that stopping prostaglandin inhibitors in glaucoma patients may be helpful for blepharitis/meibomitis.

Challenges in surgical cornea

James Reidy, MD, Chicago, discussed deep anterior lamellar keratoplasty (DALK) and tips for achieving the big bubble. 
In the U.S., the indications for keratoplasty are decreasing because of new technologies, such as crosslinking, but there’s still a role for keratoplasty and DALK, Dr. Reidy said. 
He compared penetrating keratoplasty with DALK. Both have excellent BSCVA. 
There’s a risk of endothelial rejection with penetrating keratoplasty but no such risk with DALK. 
Both may have post-keratoplasty astigmatism. There is reduced structural integrity with penetrating keratoplasty, but there is less reduction of structural integrity in DALK.
With penetrating keratoplasty, there is an increased glaucoma risk, but there is less of a risk with DALK. Penetrating keratoplasty also has greater reduction in endothelial cell density (ECD), the AC is open during the procedure, and topical steroids are needed for a longer period of time. Meanwhile, with DALK, there is less reduction of ECD, the AC is closed during the procedure, and topical steroids are needed for a shorter period of time. There is, however, more OR time needed with DALK.
Dr. Reidy offered suggestions for how to achieve the big bubble. He said to place a small bubble into the anterior chamber (with or without diluted triamcinolone). The IOP should be in the physiologic range prior to air injection into the stroma. He suggested using a blunt-tipped air cannula with a port that faces downward. Pass the needle or cannula at 80–90% of the corneal depth, Dr. Reidy said, adding that you should perform the paracentesis after achieving the big bubble. If you don’t achieve it on the first try, go to another area and try again, he said. 
Parag Majmudar, MD, Chicago, shared tips and tricks for Descemet’s membrane endothelial keratoplasty (DMEK) unfolding. Over the past 10–12 years, there has been a shift away from penetrating keratoplasty to lamellar techniques, he said. Posterior lamellar techniques are providing faster visual rehabilitation than penetrating keratoplasty, he noted. 
He mentioned the evolution in endothelial keratoplasty from DLEK to DSAEK to DMEK to PDEK. There have been some dramatic improvements along the way. However, he noted that there are still barriers in adopting DMEK. With availability of pre-loaded DMEK tissue, some of the barriers are lifted, Dr. Majmudar said, but there is still fear about how to unfold the graft.
The key point is to understand how to manipulate the graft from outside the eye using fluidic forces within the anterior chamber, he said. The most important criteria for graft unfolding is to have a shallow anterior chamber, Dr. Majmudar said. This is accomplished by digital pressure or releasing fluid from the eye via the paracentesis. Once the chamber shallows, the graft will flatten; reforming the chamber allows the graft to scroll up again. 
Dr. Majmudar also noted some graft characteristics that could influence how well a graft unfolds. In donors younger than 40, the graft has a tendency to form a tight scroll. In donors older than 40, the graft may be more “floppy” and apt to unfold spontaneously. 
In discussing some of the possible graft configurations, Dr. Majmudar noted that the double scroll with the endothelium outward would be the ideal configuration. He presented maneuvers to unfold the graft. Keeping the anterior shallow in these maneuvers is very important. Which maneuver you choose may depend on the floppiness or tightness of the scroll. 
Dr. Majmudar spoke about using gentle taps on the corneal surface for a typical double scroll, the Dirisamer two-cannula technique, which involves holding one leaflet of the graft in position with external pressure from a cannula while the other cannula sweeps aqueous across the surface of the graft and unfolds it, the use of a PDEK graft, which is slightly floppier and includes Dua’s layer, which prevents the graft from scrolling tightly, and the Dapena bubble rolling technique, which uses a very small air bubble on top to push on the edges of the graft. Dr. Majmudar said that a combination of techniques can sometimes be required, especially when there is a tight scroll. Remember that air is a barrier, he added.

Office-based glaucoma technologies, blebs, and more

Iqbal “Ike” Ahmed, MD, Toronto, Canada, discussed bleb strategies. He stressed that a posterior bleb is desirable because there are fewer metabolically active cells and it is away from the limbal stem cells. A posterior bleb is also less prone to ocular surface trauma/issues and has protection under the upper lid. You can access more conjunctival lymphatics, and there are fewer Tenon’s attachments. The posterior bleb offers improved patient comfort. All of these factors offer the potential for a better bleb, Dr. Ahmed said. 
He discussed some important points in modern day bleb differentiation and spoke about the XEN Gel Stent (Allergan, Dublin, Ireland) and InnFocus MicroShunt (Santen, Osaka, Japan). 
With adjunctive mitomycin-C, both ab interno and ab externo micro-stents appear to provide potency approaching that of the gold standard trabeculectomy, Dr. Ahmed said. 

Cataract surgery in patients with Fuchs’ dystrophy

Kathryn Colby, MD, PhD, Chicago, discussed options for cataract surgery in patients with Fuchs’ dystrophy. 
Fuchs’ dystrophy is a slowly progressive dysfunction of the corneal endothelium, she said. There is a decrease in cell count with abnormal shape and variation in cell size and guttae. Fuchs’ patients are typically diagnosed in their 40s, with intervention for patients in their 60s–70s, Dr. Colby said, adding that women are more commonly and more severely affected. There is also a hereditary component, and Fuchs’ is the most common cause of corneal transplantation in the U.S. Up to 4% of patients in the U.S. have guttae with this condition, and the guttae are associated with visual dysfunction.
Dr. Colby discussed how cataract surgery can be handled in Fuchs.’ Abnormal Descemet’s membrane in Fuchs’ is prone to detachment, she said, so it’s important to be aware of this. A near-clear incision may reduce endothelial cell loss. Additionally, a soft shell viscoelastic technique (dispersive viscoelastic against the endothelium to protect it and cohesive viscoelastic beneath) can be used. Dr. Colby said to be parsimonious with phaco power. 
When you have patients with Fuchs’ dystrophy and cataract, there are several questions to ask, she added. It’s important to consider which disease is causing the symptoms. You also have to consider the timing of the surgery; Dr. Colby often recommends earlier cataract surgery. Choosing which procedure to perform is important, as is the type of IOL used. Dr. Colby stressed the importance of assessing the risk of corneal decompensation and highlighted some of the properties of the corneal endothelium. In management of Fuchs’ dystrophy, it’s important to determine if the endothelium needs to be replaced, and Dr. Colby said that evidence from some studies suggests the endothelium is capable of self-regeneration. She shared a case she handled with deliberate Descemet’s stripping only (DSO) of a 69-year-old man with cataract and Fuchs.’ The patient had confluent central guttae with preserved peripheral endothelium and underwent phaco/IOL plus 4 mm stripping of central Descemet’s.
In conclusion, she said, if the patient has mostly cataract symptoms, you should consider phaco alone and counsel the patient regarding the visual significance of guttae and the risk of corneal decompensation. If the patient has mostly Fuchs’ symptoms with minimal cataract, she recommended considering EK or DSO. Finally, Dr. Colby said that if both diseases contribute to the patient’s symptoms, surgeons may consider phaco-EK or phaco-DSO, depending on the extent of the guttae.

New methods of capsulotomy

Richard Packard, MD, London, U.K., spoke about methods for creating capsulotomies, highlighting the CAPSULaser (Los Gatos, California). 
The femtosecond laser allows for capsulotomies of a given size, that are truly circular, in a given position, with little risk of tear out, and without variables of a manual technique. However, there are a number of caveats involved with using the femtosecond laser: a second room might be needed for the laser; it may interfere with surgical flow; the device has a high cost; there are running costs to consider; and the advantages of the femtosecond laser still need to be shown. 
Dr. Packard noted that the majority of femtosecond laser users value its ability to do an automated capsulotomy. Are there other ways to do this? He described how the CAPSULaser can help with this process. By staining the anterior capsule with a very pure trypan blue, a selective target for the laser is created, he said, adding that the laser is not pulsed but continuous, and is scanned in a single circular pattern to create the continuous curvilinear capsulotomy. Dr. Packard said that in the region of irradiation, the laser energy facilitates the molecular phase change of capsular collagen IV to elastic amorphous collagen. As the collagen undergoes this phase change, it creates the capsulotomy with a rim that has a high degree of elasticity and tear strength associated with amorphous collagen.
Dr. Packard said the CAPSULaser takes up little space in the operating room, with the device attached under the operating microscope. 
Clinical results show no pupil constriction after laser use and no untoward AC activity postoperatively. He noted that these results are from 20 patients with more than 24 months of follow-up. All corneas were clear, the endothelial cell count was as expected, the capsulotomies were well-centered and not contracted, and there was no change in IOL position. 
An additional 400 eyes have now been operated on with similar results, and a CE marking trial of 125 eyes has been submitted. 
Physicians now have devices to enable more precise capsulotomies, Dr. Packard said, adding that it remains to be seen how these will influence outcomes. IOL design is already taking advantage of innovation in capsulotomy creation, he said, and creating primary posterior capsulotomies may help eliminate PCO.

Awards and lectures

A special session featured awards and two lectures. During the session, the Ednei Nascimento Medal was given to Mauro Silveira de Queiroz Campos, MD, São Paulo, Brazil. 
Dr. Campos gave the corresponding lecture, discussing the excimer laser in refractive surgery over the last 30 years. He described the evolution of the excimer laser and procedures, including PRK and LASIK. 
Dr. Campos highlighted the use of PRK, the popularization of LASIK, and the discovery of patients with corneal ectasia showing progression. At the end of the 1990s, Dr. Campos said that PRK was somewhat of an “abandoned technique.” 
He noted that advances in surgery and laser usage at this time revolved around the ability to customize surgery. Surgeons were able to do more non-conventional treatments of the cornea, and topography-guided surgeries began to be used in 2000. He highlighted wavefront-guided treatment and stressed the importance of precise aberrometry and the tear film.
Following Dr. Campos’ lecture, Ricardo Queiroz Guimaraes, MD, Nova Lima, Brazil, was recognized. Dr. Guimaraes was not present at the meeting, but his wife spoke on his behalf.
Also during the session, the Ignácio Barraquer Award was presented to Roberto Pineda, MD, Boston. Dr. Pineda gave a lecture focusing on “Brillouin microscopy: new technology for evaluating corneal biomechanics and lens elasticity.”
Corneal biomechanics are important for understanding IOP, ectatic disorders, and at-risk corneas, Dr. Pineda said. In addition, successful corneal treatments, such as crosslinking, depend on biological and biomechanical tissue factors for effectiveness.
There are several devices to test and measure biomechanical properties of the cornea, Dr. Pineda said, specifically mentioning in vivo nondestructive tests. However, there are some limitations with current in vivo testing.
He went on to discuss Brillouin microscopy, which he described as an in vivo non-contact technique capable of recording and imaging elastic modulus of the cornea and lens in high resolution. He spoke about Brillouin scattering and how it is measured and noted current Brillouin imaging devices available. Dr. Pineda said Brillouin microscopy can be used to detect subtle differences in biomechanical properties of the cornea, can factor in and measure the fact that the cornea gets stiffer with age, can be used for assessing the cornea after crosslinking, can evaluate the cornea regionally, can be used to assess after laser vision correction, and can be used to look at the crystalline lens, among other functions.
In conclusion, Dr. Pineda said that corneal biomechanics are central to understanding many corneal conditions, however, better technology is needed to assess corneal biomechanics.
Brillouin microscopy offers the ability to measure viscoelastic properties of the cornea and lens noninvasively and tomographically, without corneal deformation. It can be used for screening patients at risk for ectasia prior to keratorefractive surgeries. 
Dr. Pineda added that Brillouin microscopy may prove useful for evaluating effectiveness of crosslinking treatments and may have a role in quantifying the impact of presbyopic therapies/interventions. 
Ultimately, Brillouin microscopy could be combined with other technology as a predictive surgical planning tool, Dr. Pineda said.

Astigmatism correction

Douglas Koch, MD, Houston, discussed 10 tips in astigmatism correction.
He questioned what the threshold for correction is. He said that for a monofocal IOL this threshold would be between 0.5 and 0.75 D of astigmatism, while with multifocal IOL patients, it’s less than 0.5 D. Overall, more than 50% of patients are going to need astigmatism correction, he said. 
His second tip was to “rethink your SIA.” You need to know your surgically induced astigmatism (SIA), Dr. Koch said, adding that it can be calculated and is likely very small. 
Next, he recommended looking at three data points or more. He suggested using biometer LEDs for power/meridian and topography for meridian and also sometimes for power. He suggested looking at the patient’s glasses because they can give you clues about what the total corneal astigmatism is (particularly posterior astigmatism). If there are discrepancies, remeasure or defer. 
Dr. Koch said that he likes to use Placido mires for all patients. This can help screen for epithelial basement membrane dystrophy (EBMD) and Salzmann’s, and it’s a good way to screen for dry eye.
Dr. Koch’s next tip was to be skeptical about readings because different devices may give different readings. You need more than one measurement, he said, and you need to verify the raw data. Tear film issues and cornea issues can alter measurements, as can the ability of the technician to get readings.
His fifth tip was to factor in the posterior cornea. To do this, he suggested measuring the anterior cornea (in limited zones) and extrapolating the posterior corneal curvature. Ignoring the posterior cornea creates errors, Dr. Koch said, particularly in post-LASIK, keratoconus, and post-PKP patients. The posterior cornea is very important for calculating total corneal astigmatism, he added, mentioning that the posterior cornea tends to be steep vertically in most patients.
Dr. Koch discussed incorporating posterior corneal astigmatism into toric IOL calculations. He suggested using regression formulas or measuring using available technology. He noted the specific regression formulas available but added that it’s still not possible to predictably measure the posterior cornea for individual patients.
It’s also important to take into account the against-the-rule (ATR) drift with age, Dr. Koch said. He suggested targeting a small amount of with-the-rule (WTR) astigmatism to account for the ATR shift with age. 
Dr. Koch said he uses relaxing incisions for less than or equal to 1.5 D WTR and less than or equal to 0.5 D ATR. For anything above that, he said a toric would be a good choice. For greater than 4 D, he does a toric first and defers relaxing incisions. 
Dr. Koch next stressed the importance of alignment. It’s important to know the difference that can occur between when a patient is sitting and lying down and noted that he still uses manual marking.
His last tip was about preventing postoperative rotation. This usually occurs in the first 24 hours, and patients most at risk are those with large capsules or high myopes. 
To help prevent this, Dr. Koch suggested removing all OVD from behind the IOL, pushing the IOL posteriorly to “seat it,” leaving the eye at a normal IOP (don’t leave it overinflated), moving the eye to test stability, and using a CTR if the IOL seems mobile.

Toric IOLs and astigmatism

Bruna Ventura, MD, Recife, Brazil, discussed using toric IOLs and other considerations for astigmatism. 
She first discussed the population of patients with astigmatism and cataracts. She noted the prevalence of astigmatism in cataract patients and said that around 6% of patients present with less than 0.5 D of astigmatism, 58% with between 0.5 D and 1 D, and 36% with greater than 1 D. Greater than 0.75 D of astigmatism can affect the quality of life of the patient. 
To optimize results with toric IOLs, Dr. Ventura shared several tips. 
She first discussed mapping the cornea and stressed the importance of having at least two devices to obtain measurements. She said physicians should pay attention to the quality of the exam.
Dr. Ventura highlighted the importance of including the posterior corneal astigmatism and specifically mentioned Dr. Koch’s work in this field. She also noted that you can use devices to evaluate the posterior astigmatism, nomograms, toric calculators, adjustment coefficients, and the Abulafia-Koch formula. In addition to the posterior corneal astigmatism, Dr. Ventura stressed the importance of calculating SIA. 
She also mentioned the importance of axis marking and maintaining the IOL at the correct axis.

Editors’ note: Reporting on Dr. Ventura’s presentation was based on a translation from Portuguese to English.

Phaco and special cases

Kathryn Colby, MD, PhD, Chicago, discussed optimizing the ocular surface prior to cataract surgery. Dry eye is common in the cataract age range, and several studies estimate that around 80% of patients are affected. Many of these patients are asymptomatic and undiagnosed. 
Dr. Colby said that the air-tear film interface is the most important component of the refractive state of the eye. Poor surface quality impacts visual acuity and patient satisfaction, especially in premium IOL patients.
She offered a number of tips to avoid trouble with dry eye. Make the diagnosis before you operate, she said. Patient education is key, Dr. Colby said, and you need to stress that this is a chronic disease and that patients may need daily intervention. It’s important to manage patient expectations and to optimize the tear film before surgery, often continuing to do so after surgery as well. Cataract surgery can decompensate a borderline dry eye patient. 
Dr. Colby also spoke about the mechanism of dry eye and highlighted features, medical management, and surgical management of the different types of dry eye disease.

Charles Kelman Lecture 

Takayuki Akahoshi, MD, Tokyo, Japan, gave the meeting’s Charles Kelman Lecture. Dr. Akahoshi’s lecture focused on phaco prechop. He also discussed his experience in Brazil, noting that it was nearly 20 years ago when he first visited the country and was asked to share his phaco prechop technique. He shared his history of cataract surgery using phaco prechop, which he described as a “mechanical nucleofracture performed prior to phacoemulsification.” He said he first began the technique in 1992 in Japan. 
The femtosecond laser can now prechop, however, it has some limitations because the posterior plate will remain undivided using this technology. Therefore, a manual method may be preferred.
Dr. Akahoshi detailed the phaco prechop technique, noting that before performing it, you should ensure corneal protection, have a complete CCC, and perform sufficient hydrodissection.

Target refractive error

Brian Little, MD, London, U.K., discussed target refractive error and causes, prevention, and management of this.
He first said to have an error, you have to have a target. What are we aiming for? In terms of benchmarking outcomes, the target is to have 85% within 1 D of the target. The normal distribution of refractive error is 66% of eyes within 1 D of emmetropia. 
Dr. Little focused on some of the causes of refractive error. Before optical biometry, 54% of refractive surprises were due to errors in axial length measurement, with 38% due to errors in predicting IOL position, and 8% due to keratometry errors. Now, optical biometry offers improved axial length measurement, and axial length measurement is responsible for only 17% of errors. Dr. Little noted that other causes of refractive error now are prediction of postop IOL position (36%), errors in postoperative refraction (27%), and keratometry errors (10%). Dr. Little added that it’s important to identify high risk eyes.
If something does happen, be sure to apologize, explain the situation, and support the patient.
He moved on to discuss prevention of refractive error and noted that enhancing the accuracy of measurements can help with this. Modern software protocols recheck any measurements with low probability, but it’s difficult to differentiate between a normal unusual measurement in an unusual eye versus an error. Dr. Little said that it’s important to crosscheck the IOL power calculation against the patient’s refractive history.
Particularly in high-risk eyes, Dr. Little said to be alert, recheck the biometry and have a low threshold for repeating, use appropriate and up-to-date formulae, reconcile biometry measurements against the patient’s refractive history, and warn patients about the high probability of error and need for a possible secondary procedure/enhancement.
Dr. Little concluded by talking about correction of refractive error. He said to assess and identify the cause by doing a methodical assessment. Check for accurate subjective refraction, repeat the biometry measurements, and recalculate IOL power. 
Then, rectify the situation.
He said to document stable refraction prior to intervention and weigh the risks and benefits of correction. Laser vision correction, a piggyback IOL, or IOL exchange may be needed, depending on the situation. Laser correction or a piggyback IOL are more predictable and preferable to an IOL exchange, Dr. Little said.

Reporting from the 2018 BRASCRS annual meeting Reporting from the 2018 BRASCRS annual meeting
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