CASE REPORT
Toric intraocular lens rotation to optimize refractive outcome despite appropriate intraoperative positioning James C. Lockwood, BA, J. Bradley Randleman, MD
We present 3 eyes of 2 patients who benefitted from toric intraocular lens (IOL) rotation despite appropriate intraoperative positioning. In each case, preoperative astigmatism measurements were obtained by manual keratometry, partial coherence interferometry, and corneal topography. In Case 1, a dramatic shift in corneal topography occurred after surgery, resulting in the need to rotate the toric IOL to maximize the refractive outcome. In Case 2 (both eyes), no significant change in topography occurred, but IOL rotation was required to maximize the refractive outcome despite appropriate IOL alignment based on preoperative measurements. Using an online toric IOL calculator, it was determined that rotation of the IOL would result in significantly improved astigmatic outcomes. At the final evaluation 2 months after IOL rotation, the residual manifest astigmatism was 0.50 diopter (D) in Case 1 and 0 D (right eye) and 0.75 D (left eye) in Case 2. Use of the toric IOL online calculator maximized the uncorrected visual and refractive outcomes. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2015; 41:878–883 Q 2015 ASCRS and ESCRS
Despite advanced technology to determine preoperative measurements,1 refractive surprises may occur after implantation of toric intraocular lenses (IOLs). Proper IOL alignment is key to effectiveness in treating corneal astigmatism. The most common reason for toric IOL misalignment appears to be inaccurate preoperative measurements.2 Using multiple technologies to determine astigmatism magnitude and axis can significantly reduce these measurement errors.3
Submitted: November 19, 2014. Final revision submitted: December 31, 2014. Accepted: December 31, 2014. From Emory University School of Medicine (Lockwood, Randleman), the Department of Ophthalmology (Randleman), Emory University, and Emory Vision at the Emory Eye Center (Randleman), Atlanta, Georgia, USA. Supported in part by an unrestricted departmental grant to Emory University Department of Ophthalmology, Atlanta, Georgia, from Research to Prevent Blindness, Inc., New York, New York, USA. Corresponding author: J. Bradley Randleman, MD, Emory Eye Center, 875 Johnson Ferry Road, Suite 100, Atlanta, Georgia, 30342, USA. E-mail: [email protected].
878
Q 2015 ASCRS and ESCRS Published by Elsevier Inc.
Nevertheless, residual or induced astigmatism can arise after toric IOL implantation. We present 2 patients who benefitted from toric IOL rotation despite appropriate initial IOL positioning. CASE REPORTS Case 1 A 59-year-old woman presented for cataract evaluation. She had a visually significant cataract and significant Salzmann nodules in the right eye. The manifest refraction was C1.00 C3.50 25, yielding a corrected distance visual acuity (CDVA) of 20/40, and corneal topography demonstrated 2.2 diopters (D) of corneal astigmatism at 24 degrees. After treatment options were discussed, the patient elected to have manual superficial keratectomy prior to cataract surgery in the right eye. Six weeks after superficial keratectomy, repeat corneal imaging showed a symmetric bowtie pattern with 2.1 D of corneal astigmatism at 24 degrees. Preoperative astigmatism measurements were subsequently obtained with manual keratometry (K), partial coherence interferometry (PCI) (IOLMaster, Carl Zeiss Meditec AG), and corneal topography (Atlas 9000, Carl Zeiss Meditec AG) (Figure 1). Consensus K values of 43.38/45.12 @ 110, derived by using measured K values from the PCI and the axis obtained by the topographer, were input into the Acrysof IQ toric IOL calculator (Alcon Laboratories, Inc.). A C24.00 D toric IOL (model SN6AT5, Alcon http://dx.doi.org/10.1016/j.jcrs.2015.02.007 0886-3350
CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
879
Figure 1. Case 1: Preoperative (left) and postoperative (right) topography of the right eye show a significant shift in topographic pattern and anterior corneal astigmatism after cataract surgery.
Laboratories, Inc.) was selected for near target ( 2.00 D) using a surgeon-induced astigmatism value of 0.5 90 and target placement at 106 degrees. The IOL was implanted and oriented at the 105-degree meridian after uneventful cataract extraction through a 2.4 mm clear corneal temporal incision. During the first 6 weeks postoperatively, the patient complained that her vision remained blurred. At 2 months, the uncorrected distance visual acuity (UDVA) was 20/60, the uncorrected near visual acuity (UNVA) was Jaeger (J) 4, and the manifest refraction was 3.00 C3.25 12, yielding a CDVA of 20/20. Slitlamp anterior segment and fundus examinations were unremarkable, and the IOL was confirmed to be oriented at 105 degrees as intended. Atlas topography showed an anterior corneal astigmatism of 0.4 @ 65 (Figure 1). Using an online toric IOL calculator, it was determined that rotation of the IOL to 172 degrees would result in approximately 0.28 D of residual astigmatism (Figure 2). After the risks, benefits, and options were discussed with the patient, toric IOL rotation was performed, repositioning the IOL to the 170-degree meridian in the operating room. At the final evaluation 2 months after IOL rotation, UDVA was 20/50, UNVA was J1, and the manifest refraction was 1.75 C0.50 50, yielding a CDVA of 20/20. The patient was happy with the UNVA.
Case 2 (Right and Left Eyes) A 65-year-old woman presented for cataract evaluation with visually significant cataracts and a manifest refraction of C2.50 C1.50 20 in the right eye and C2.50 C1.00 180 in the left eye, yielding a CDVA of 20/30 and 20/25, respectively. In both eyes, the preoperative astigmatism measurements were obtained with manual keratometry, PCI, and corneal topography (Figures 3 and 4). In the right eye, consensus K values of 43.95/44.94 @ 59 were input into the online toric IOL calculator and a C27.00 D toric IOL (model SN6AT4, Alcon Laboratories, Inc.) was selected for distance target (0.02 D) using a surgeon-induced astigmatism value of 0.5 90 and target placement at 65 degrees per toric IOL calculator recommendations. The IOL was
implanted and oriented at the 65-degree meridian after uneventful cataract extraction through a 2.4 mm clear corneal temporal incision. In the left eye, consensus K values of 44.59/45.06 @ 77 were used and a C26.5 D toric IOL (model SN6AT3, Alcon Laboratories, Inc.) was selected for plano target (0.10 D). The IOL was implanted and oriented at 85 degrees per toric IOL calculator recommendations using the same technique as in the right eye. Postoperatively, the UDVA stabilized at 20/60 in both eyes, with manifest refractions of 1.25 C1.50 180 in the right eye and 2.00 C2.00 160 in the left eye, yielding a CDVA of 20/20 in both eyes. Slitlamp anterior segment and fundus examinations were unremarkable in both eyes, and the IOLs were confirmed to be oriented at 70 degrees (target 65 degrees) in the right eye and 85 degrees (target 85 degrees) in the left eye. Using the online toric IOL calculator program, it was determined that rotation of the IOL in the right eye to 36 degrees would result in approximately 0.52 D astigmatism at 126 degrees (Figure 5) and rotating the IOL in the left eye to 148 degrees would result in 0.19 D astigmatism at 145 degrees (Figure 6). Toric IOL repositioning was performed in the 2 eyes a few weeks apart; the target repositioning was the 40-degree meridian in the right eye and the 145-degree meridian in the left eye. At the final evaluation 2 months after IOL rotation in the right eye and 1 month after rotation in the left eye, UDVA was 20/30 (right eye) and 20/25 (left eye); manifest refraction of 0.50 D sphere in the right eye yielded a CDVA of 20/20 and of 0.25 C0.75 165 in the left eye yielded a CDVA of 20/20. The patient was happy with her UDVA.
DISCUSSION Reasons for toric IOL refractive surprises are likely multifactorial and include preoperative measurement error,2,3 alignment error, toric IOL rotation,4 and influence of posterior corneal astigmatism that is currently not measured with most devices.5,6 Surgically induced astigmatism (SIA) may vary, which can result in residual astigmatism that differs from that predicted by toric IOL calculators.7
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
Figure 2. Case 1: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and shows that rotation to the 172-degree meridian should minimize residual astigmatism.
In the 2 cases we present, no measurement errors, alignment issues, or postoperative IOL rotations occurred. Despite this, both cases required rotation for optimum visual outcomes, in the first case because of postoperative topographic changes (Figure 1) and in
the second case because of undetermined issues, as topography and astigmatism did not change significantly postoperatively in either eye (Figures 3 and 4). In Case 2, measured preoperative astigmatism was relatively low, with some variation between
Figure 3. Case 2: Preoperative (left) and postoperative (right) topography of the right eye shows relative stability of the topographic pattern.
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
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Figure 4. Case 2: Preoperative (left) and postoperative (right) topography of the left eye shows relative stability of the topographic pattern.
measurement devices. It is likely that in cases with low anterior corneal astigmatism, other factors such as SIA, unmeasured posterior astigmatism, and postoperative variability due to the healing response will play a relatively larger role. Therefore, these patients
may require toric IOL repositioning more frequently postoperatively, and if too much variation between measurements exists, toric IOL implantation may not be advisable. Other available techniques for astigmatic correction, including on-axis incisions, limbal relaxing
Figure 5. Case 2, right eye: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and that rotation to the 36-degree meridian should minimize residual astigmatism.
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
Figure 6. Case 2, left eye: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and that rotation to the 148degree meridian should minimize residual astigmatism.
incisions (LRIs), and planned postoperative excimer laser corneal refractive surgery (surface ablation or laser in situ keratomileusis [LASIK]), can be used in these cases. Previous studies report comparable predictability with toric IOLs and LRIs in patients with lower amounts of astigmatism.8 Nevertheless, in our case, after toric IOL rotation, the patient reported excellent uncorrected acuity and had residual astigmatism much lower than would have been anticipated with a nontoric IOL. Currently, we predominately use toric IOLs for astigmatic correction at the time of cataract surgery within their indicated range, and the majority of these cases achieve target refraction without incident.A A variety of techniques and software analyses are available to assist in toric IOL repositioning.9 In our cases, we used the online software created by Drs. Berdahl and Hardten.B The simple-to-use web site was beneficial in identifying the appropriate location for rotation based on postoperative manifest refraction and implanted IOL cylinder power and orientation and resulted in improved uncorrected acuity in both cases. In other cases, where it is determined that toric IOL rotation would not significantly
improve the final refraction, IOL exchange or corneal refractive surgery (surface ablation or LASIK) may be of benefit. In summary, postoperative toric IOL rotation may be beneficial for some patients even when no IOL rotation has occurred and the achieved placement is identical to the target placement. As more patients desire optimized refractive correction at the time of cataract extraction, there will be more opportunities for toric IOL implantation but potentially more situations that require postoperative toric IOL rotation to maximize visual outcomes. REFERENCES 1. Reinstein DZ, Gobbe M, Archer TJ. Anterior segment biometry: a study and review of resolution and repeatability data. J Refract Surg 2012; 28:509–520 2. Hirnschall N, Hoffmann PC, Draschl P, Maedel S, Findl O. Evaluation of factors influencing the remaining astigmatism after toric intraocular lens implantation. J Refract Surg 2014; 30:394–400 3. Browne AW, Osher RH. Optimizing precision in toric lens selection by combining keratometry techniques. J Refract Surg 2014; 30:67–72 4. Felipe A, Artigas JM, Dıez-Ajenjo A, Garcıa-Domene C, Alcocer P. Residual astigmatism produced by toric
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
5.
6.
7.
8.
intraocular lens rotation. J Cataract Refract Surg 2011; 37: 1895–1901 Koch DD, Jenkins RB, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: effect of posterior corneal astigmatism. J Cataract Refract Surg 2013; 39: 1803–1809 Nemeth G, Berta A, Szalai E, Hassan Z, Modis L Jr. Analysis of surgically induced astigmatism on the posterior surface of the cornea. J Refract Surg 2014; 30:604–608 Berdahl JP, Hardten DR. Residual astigmatism after toric intraocular lens implantation [letter]. J Cataract Refract Surg 2012; 38:730–731; reply by A Felipe, JM Artigas 731–732 Poll JT, Wang L, Koch DD, Weikert MP. Correction of astigmatism during cataract surgery: toric intraocular lens compared to
883
peripheral corneal relaxing incisions. J Refract Surg 2011; 27:165–171 9. Alpins N, Ong JKY, Stamatelatos G. Refractive surprise after toric intraocular lens implantation: graph analysis. J Cataract Refract Surg 2014; 40:283–294
OTHER CITED MATERIAL A. Lockwood JC, “Comparison of Alcon and Holladay Toric IOL Calculator Recommendations in Patients With Toric IOL Implantation,” e-poster RJ. RP30040879 presented at the annual meeting of the American Academy of Ophthalmology, Chicago, Illinois, USA, October 2014 B. Berdahl J, Hardten D. Toric Results Analyzer. Available at: http://astigmatismfix.com. Accessed February 2, 2015
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
Toric intraocular lens rotation to optimize refractive outcome despite appropriate intraoperative positioning James C. Lockwood, BA, J. Bradley Randleman, MD
We present 3 eyes of 2 patients who benefitted from toric intraocular lens (IOL) rotation despite appropriate intraoperative positioning. In each case, preoperative astigmatism measurements were obtained by manual keratometry, partial coherence interferometry, and corneal topography. In Case 1, a dramatic shift in corneal topography occurred after surgery, resulting in the need to rotate the toric IOL to maximize the refractive outcome. In Case 2 (both eyes), no significant change in topography occurred, but IOL rotation was required to maximize the refractive outcome despite appropriate IOL alignment based on preoperative measurements. Using an online toric IOL calculator, it was determined that rotation of the IOL would result in significantly improved astigmatic outcomes. At the final evaluation 2 months after IOL rotation, the residual manifest astigmatism was 0.50 diopter (D) in Case 1 and 0 D (right eye) and 0.75 D (left eye) in Case 2. Use of the toric IOL online calculator maximized the uncorrected visual and refractive outcomes. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2015; 41:878–883 Q 2015 ASCRS and ESCRS
Despite advanced technology to determine preoperative measurements,1 refractive surprises may occur after implantation of toric intraocular lenses (IOLs). Proper IOL alignment is key to effectiveness in treating corneal astigmatism. The most common reason for toric IOL misalignment appears to be inaccurate preoperative measurements.2 Using multiple technologies to determine astigmatism magnitude and axis can significantly reduce these measurement errors.3
Submitted: November 19, 2014. Final revision submitted: December 31, 2014. Accepted: December 31, 2014. From Emory University School of Medicine (Lockwood, Randleman), the Department of Ophthalmology (Randleman), Emory University, and Emory Vision at the Emory Eye Center (Randleman), Atlanta, Georgia, USA. Supported in part by an unrestricted departmental grant to Emory University Department of Ophthalmology, Atlanta, Georgia, from Research to Prevent Blindness, Inc., New York, New York, USA. Corresponding author: J. Bradley Randleman, MD, Emory Eye Center, 875 Johnson Ferry Road, Suite 100, Atlanta, Georgia, 30342, USA. E-mail: [email protected].
878
Q 2015 ASCRS and ESCRS Published by Elsevier Inc.
Nevertheless, residual or induced astigmatism can arise after toric IOL implantation. We present 2 patients who benefitted from toric IOL rotation despite appropriate initial IOL positioning. CASE REPORTS Case 1 A 59-year-old woman presented for cataract evaluation. She had a visually significant cataract and significant Salzmann nodules in the right eye. The manifest refraction was C1.00 C3.50 25, yielding a corrected distance visual acuity (CDVA) of 20/40, and corneal topography demonstrated 2.2 diopters (D) of corneal astigmatism at 24 degrees. After treatment options were discussed, the patient elected to have manual superficial keratectomy prior to cataract surgery in the right eye. Six weeks after superficial keratectomy, repeat corneal imaging showed a symmetric bowtie pattern with 2.1 D of corneal astigmatism at 24 degrees. Preoperative astigmatism measurements were subsequently obtained with manual keratometry (K), partial coherence interferometry (PCI) (IOLMaster, Carl Zeiss Meditec AG), and corneal topography (Atlas 9000, Carl Zeiss Meditec AG) (Figure 1). Consensus K values of 43.38/45.12 @ 110, derived by using measured K values from the PCI and the axis obtained by the topographer, were input into the Acrysof IQ toric IOL calculator (Alcon Laboratories, Inc.). A C24.00 D toric IOL (model SN6AT5, Alcon http://dx.doi.org/10.1016/j.jcrs.2015.02.007 0886-3350
CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
879
Figure 1. Case 1: Preoperative (left) and postoperative (right) topography of the right eye show a significant shift in topographic pattern and anterior corneal astigmatism after cataract surgery.
Laboratories, Inc.) was selected for near target ( 2.00 D) using a surgeon-induced astigmatism value of 0.5 90 and target placement at 106 degrees. The IOL was implanted and oriented at the 105-degree meridian after uneventful cataract extraction through a 2.4 mm clear corneal temporal incision. During the first 6 weeks postoperatively, the patient complained that her vision remained blurred. At 2 months, the uncorrected distance visual acuity (UDVA) was 20/60, the uncorrected near visual acuity (UNVA) was Jaeger (J) 4, and the manifest refraction was 3.00 C3.25 12, yielding a CDVA of 20/20. Slitlamp anterior segment and fundus examinations were unremarkable, and the IOL was confirmed to be oriented at 105 degrees as intended. Atlas topography showed an anterior corneal astigmatism of 0.4 @ 65 (Figure 1). Using an online toric IOL calculator, it was determined that rotation of the IOL to 172 degrees would result in approximately 0.28 D of residual astigmatism (Figure 2). After the risks, benefits, and options were discussed with the patient, toric IOL rotation was performed, repositioning the IOL to the 170-degree meridian in the operating room. At the final evaluation 2 months after IOL rotation, UDVA was 20/50, UNVA was J1, and the manifest refraction was 1.75 C0.50 50, yielding a CDVA of 20/20. The patient was happy with the UNVA.
Case 2 (Right and Left Eyes) A 65-year-old woman presented for cataract evaluation with visually significant cataracts and a manifest refraction of C2.50 C1.50 20 in the right eye and C2.50 C1.00 180 in the left eye, yielding a CDVA of 20/30 and 20/25, respectively. In both eyes, the preoperative astigmatism measurements were obtained with manual keratometry, PCI, and corneal topography (Figures 3 and 4). In the right eye, consensus K values of 43.95/44.94 @ 59 were input into the online toric IOL calculator and a C27.00 D toric IOL (model SN6AT4, Alcon Laboratories, Inc.) was selected for distance target (0.02 D) using a surgeon-induced astigmatism value of 0.5 90 and target placement at 65 degrees per toric IOL calculator recommendations. The IOL was
implanted and oriented at the 65-degree meridian after uneventful cataract extraction through a 2.4 mm clear corneal temporal incision. In the left eye, consensus K values of 44.59/45.06 @ 77 were used and a C26.5 D toric IOL (model SN6AT3, Alcon Laboratories, Inc.) was selected for plano target (0.10 D). The IOL was implanted and oriented at 85 degrees per toric IOL calculator recommendations using the same technique as in the right eye. Postoperatively, the UDVA stabilized at 20/60 in both eyes, with manifest refractions of 1.25 C1.50 180 in the right eye and 2.00 C2.00 160 in the left eye, yielding a CDVA of 20/20 in both eyes. Slitlamp anterior segment and fundus examinations were unremarkable in both eyes, and the IOLs were confirmed to be oriented at 70 degrees (target 65 degrees) in the right eye and 85 degrees (target 85 degrees) in the left eye. Using the online toric IOL calculator program, it was determined that rotation of the IOL in the right eye to 36 degrees would result in approximately 0.52 D astigmatism at 126 degrees (Figure 5) and rotating the IOL in the left eye to 148 degrees would result in 0.19 D astigmatism at 145 degrees (Figure 6). Toric IOL repositioning was performed in the 2 eyes a few weeks apart; the target repositioning was the 40-degree meridian in the right eye and the 145-degree meridian in the left eye. At the final evaluation 2 months after IOL rotation in the right eye and 1 month after rotation in the left eye, UDVA was 20/30 (right eye) and 20/25 (left eye); manifest refraction of 0.50 D sphere in the right eye yielded a CDVA of 20/20 and of 0.25 C0.75 165 in the left eye yielded a CDVA of 20/20. The patient was happy with her UDVA.
DISCUSSION Reasons for toric IOL refractive surprises are likely multifactorial and include preoperative measurement error,2,3 alignment error, toric IOL rotation,4 and influence of posterior corneal astigmatism that is currently not measured with most devices.5,6 Surgically induced astigmatism (SIA) may vary, which can result in residual astigmatism that differs from that predicted by toric IOL calculators.7
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
Figure 2. Case 1: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and shows that rotation to the 172-degree meridian should minimize residual astigmatism.
In the 2 cases we present, no measurement errors, alignment issues, or postoperative IOL rotations occurred. Despite this, both cases required rotation for optimum visual outcomes, in the first case because of postoperative topographic changes (Figure 1) and in
the second case because of undetermined issues, as topography and astigmatism did not change significantly postoperatively in either eye (Figures 3 and 4). In Case 2, measured preoperative astigmatism was relatively low, with some variation between
Figure 3. Case 2: Preoperative (left) and postoperative (right) topography of the right eye shows relative stability of the topographic pattern.
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
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Figure 4. Case 2: Preoperative (left) and postoperative (right) topography of the left eye shows relative stability of the topographic pattern.
measurement devices. It is likely that in cases with low anterior corneal astigmatism, other factors such as SIA, unmeasured posterior astigmatism, and postoperative variability due to the healing response will play a relatively larger role. Therefore, these patients
may require toric IOL repositioning more frequently postoperatively, and if too much variation between measurements exists, toric IOL implantation may not be advisable. Other available techniques for astigmatic correction, including on-axis incisions, limbal relaxing
Figure 5. Case 2, right eye: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and that rotation to the 36-degree meridian should minimize residual astigmatism.
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
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CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
Figure 6. Case 2, left eye: Printout from an online toric IOL calculator shows the residual astigmatism curve based on toric IOL positioning using current patient refractive values and that rotation to the 148degree meridian should minimize residual astigmatism.
incisions (LRIs), and planned postoperative excimer laser corneal refractive surgery (surface ablation or laser in situ keratomileusis [LASIK]), can be used in these cases. Previous studies report comparable predictability with toric IOLs and LRIs in patients with lower amounts of astigmatism.8 Nevertheless, in our case, after toric IOL rotation, the patient reported excellent uncorrected acuity and had residual astigmatism much lower than would have been anticipated with a nontoric IOL. Currently, we predominately use toric IOLs for astigmatic correction at the time of cataract surgery within their indicated range, and the majority of these cases achieve target refraction without incident.A A variety of techniques and software analyses are available to assist in toric IOL repositioning.9 In our cases, we used the online software created by Drs. Berdahl and Hardten.B The simple-to-use web site was beneficial in identifying the appropriate location for rotation based on postoperative manifest refraction and implanted IOL cylinder power and orientation and resulted in improved uncorrected acuity in both cases. In other cases, where it is determined that toric IOL rotation would not significantly
improve the final refraction, IOL exchange or corneal refractive surgery (surface ablation or LASIK) may be of benefit. In summary, postoperative toric IOL rotation may be beneficial for some patients even when no IOL rotation has occurred and the achieved placement is identical to the target placement. As more patients desire optimized refractive correction at the time of cataract extraction, there will be more opportunities for toric IOL implantation but potentially more situations that require postoperative toric IOL rotation to maximize visual outcomes. REFERENCES 1. Reinstein DZ, Gobbe M, Archer TJ. Anterior segment biometry: a study and review of resolution and repeatability data. J Refract Surg 2012; 28:509–520 2. Hirnschall N, Hoffmann PC, Draschl P, Maedel S, Findl O. Evaluation of factors influencing the remaining astigmatism after toric intraocular lens implantation. J Refract Surg 2014; 30:394–400 3. Browne AW, Osher RH. Optimizing precision in toric lens selection by combining keratometry techniques. J Refract Surg 2014; 30:67–72 4. Felipe A, Artigas JM, Dıez-Ajenjo A, Garcıa-Domene C, Alcocer P. Residual astigmatism produced by toric
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
CASE REPORT: TORIC IOL ROTATION TO OPTIMIZE REFRACTIVE OUTCOME
5.
6.
7.
8.
intraocular lens rotation. J Cataract Refract Surg 2011; 37: 1895–1901 Koch DD, Jenkins RB, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: effect of posterior corneal astigmatism. J Cataract Refract Surg 2013; 39: 1803–1809 Nemeth G, Berta A, Szalai E, Hassan Z, Modis L Jr. Analysis of surgically induced astigmatism on the posterior surface of the cornea. J Refract Surg 2014; 30:604–608 Berdahl JP, Hardten DR. Residual astigmatism after toric intraocular lens implantation [letter]. J Cataract Refract Surg 2012; 38:730–731; reply by A Felipe, JM Artigas 731–732 Poll JT, Wang L, Koch DD, Weikert MP. Correction of astigmatism during cataract surgery: toric intraocular lens compared to
883
peripheral corneal relaxing incisions. J Refract Surg 2011; 27:165–171 9. Alpins N, Ong JKY, Stamatelatos G. Refractive surprise after toric intraocular lens implantation: graph analysis. J Cataract Refract Surg 2014; 40:283–294
OTHER CITED MATERIAL A. Lockwood JC, “Comparison of Alcon and Holladay Toric IOL Calculator Recommendations in Patients With Toric IOL Implantation,” e-poster RJ. RP30040879 presented at the annual meeting of the American Academy of Ophthalmology, Chicago, Illinois, USA, October 2014 B. Berdahl J, Hardten D. Toric Results Analyzer. Available at: http://astigmatismfix.com. Accessed February 2, 2015
J CATARACT REFRACT SURG - VOL 41, APRIL 2015
