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Papers in this Session
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The Prevalence of Preoperative Medical Testing and Consultation in Cataract Surgery Patients at a Teaching Hospital
Authors
Elaine M. Tran
Jessica Eskander
Lan Jiang, MS
Paul B. Greenberg, MD, MPH, ABO
Methods
This retrospective chart review included patients who received cataract surgery from 2014 to 2018 at an academic-affiliated Veterans Affairs Medical Center. For patients with bilateral cataracts, we excluded the second surgery to ensure independent selection. We recorded Charlson Comorbidity Index (CCI) scores and heart disease status. The outcomes of interest were preoperative testing, such as complete blood count, chemistry panel, and echocardiography, and consultation (office visits to non-ophthalmologists) during the period between the date the decision was made to proceed with surgery and the cataract surgery date.
Results
We reviewed 1320 charts; 1257 (95.2%) patients met the study criteria. The mean CCI score was 1.7; 42.0% (528/1257) had heart disease. The prevalence of preoperative testing was 0.08% (1/1257). The prevalence of preoperative consultation was 4.2% (53/1257); 86.8% (46/53) of patients received cardiology consultation; 17.0% (9/53) pulmonology; and 15.1% (8/53) primary care. Of the patients who received cardiac consultation, 63.0% (29/46) had heart disease; the remaining had an electrocardiogram abnormality.
Conclusion
There was a low prevalence of preoperative medical testing and consultation for cataract surgery at this teaching hospital. Further studies using medical record data are needed to assess the current rates and role of preoperative testing and consultation for cataract surgery patients.
Elaine M. Tran
Jessica Eskander
Lan Jiang, MS
Paul B. Greenberg, MD, MPH, ABO
Methods
This retrospective chart review included patients who received cataract surgery from 2014 to 2018 at an academic-affiliated Veterans Affairs Medical Center. For patients with bilateral cataracts, we excluded the second surgery to ensure independent selection. We recorded Charlson Comorbidity Index (CCI) scores and heart disease status. The outcomes of interest were preoperative testing, such as complete blood count, chemistry panel, and echocardiography, and consultation (office visits to non-ophthalmologists) during the period between the date the decision was made to proceed with surgery and the cataract surgery date.
Results
We reviewed 1320 charts; 1257 (95.2%) patients met the study criteria. The mean CCI score was 1.7; 42.0% (528/1257) had heart disease. The prevalence of preoperative testing was 0.08% (1/1257). The prevalence of preoperative consultation was 4.2% (53/1257); 86.8% (46/53) of patients received cardiology consultation; 17.0% (9/53) pulmonology; and 15.1% (8/53) primary care. Of the patients who received cardiac consultation, 63.0% (29/46) had heart disease; the remaining had an electrocardiogram abnormality.
Conclusion
There was a low prevalence of preoperative medical testing and consultation for cataract surgery at this teaching hospital. Further studies using medical record data are needed to assess the current rates and role of preoperative testing and consultation for cataract surgery patients.
Changes in Angle Kappa and Angle Alpha before and after Cataract Surgery (No Audio)
Authors
Rui Wang, PhD
Tan Long, PhD, MD
Methods
Prospective non-randomized, non-comparative cases series. Eighty-one eyes of 70 patients who performed phacoemulsification were included. The magnitudes and orientations of angle kappa and angle alpha pre- and postoperatively were compared, respectively.
Results
The magnitude of angle kappa significantly decreased after the phacoemulsification. No significant differences were observed between pre- and postoperative angle kappa in orientation, and between pre- and postoperative angle alpha. The correlations between pre- and postoperative angle kappa and alpha were significant. There were displacement vectors for angle kappa (0.15±0.10) and angle alpha(0.12±0.12) after the phacoemulsification. Locations of angle kappa of right and left eyes were scattered mostly in temporal side of corneal light reflection while the locations of angle alpha were well organized in horizontal on temporal sides of corneal light reflection.
Conclusion
The distribution of angle alpha is more organized compared to angle kappa. Angle kappa may change after phacoemulsification. During preoperative evaluation for cataract patients planning to have mIOLs implanted, angle alpha may be a more reliable and stable factor compared to angle kappa.
Rui Wang, PhD
Tan Long, PhD, MD
Methods
Prospective non-randomized, non-comparative cases series. Eighty-one eyes of 70 patients who performed phacoemulsification were included. The magnitudes and orientations of angle kappa and angle alpha pre- and postoperatively were compared, respectively.
Results
The magnitude of angle kappa significantly decreased after the phacoemulsification. No significant differences were observed between pre- and postoperative angle kappa in orientation, and between pre- and postoperative angle alpha. The correlations between pre- and postoperative angle kappa and alpha were significant. There were displacement vectors for angle kappa (0.15±0.10) and angle alpha(0.12±0.12) after the phacoemulsification. Locations of angle kappa of right and left eyes were scattered mostly in temporal side of corneal light reflection while the locations of angle alpha were well organized in horizontal on temporal sides of corneal light reflection.
Conclusion
The distribution of angle alpha is more organized compared to angle kappa. Angle kappa may change after phacoemulsification. During preoperative evaluation for cataract patients planning to have mIOLs implanted, angle alpha may be a more reliable and stable factor compared to angle kappa.
The Correlation Analysis between Location of Intraocular Lensand Angle Kappa and Alpha in Cataract Patients (No Audio)
Authors
Tan Long, PhD, MD
Rui Wang, PhD
Methods
Prospective non-randomized, non-comparative cases series. Ninety-one eyes of 74 patients who performed phacoemulsification were included. Pre- and postoperative angle kappa and alpha and the center of IOL relative to visual axis (CIV) were evaluated using iTrace.
Results
No correlations were found between CIV and preoperative angle kappa and alpha, respectively. However, the magnitude of CIV waspositively correlated to the length of the optic axis. Locations of CIV were scattered in all directions centered on corneal light reflection. Locations of angle kappa and angle alpha distributed mostly in the temporal side of corneal light reflection. Locations of angle alpha were more organized than that of angle kappa. The magnitude of angle kappa significantly decreased after the phacoemulsification. No significant differences were observed between pre- and postoperative angle kappa in orientation, and between pre- and postoperative angle alpha.
Conclusion
The CIV was not related to preoperative angle kappa and angle alpha. Angle kappa may change after the cataract surgery. The distanceof CIV may be greater in cataract patients with longer optic axis.
Tan Long, PhD, MD
Rui Wang, PhD
Methods
Prospective non-randomized, non-comparative cases series. Ninety-one eyes of 74 patients who performed phacoemulsification were included. Pre- and postoperative angle kappa and alpha and the center of IOL relative to visual axis (CIV) were evaluated using iTrace.
Results
No correlations were found between CIV and preoperative angle kappa and alpha, respectively. However, the magnitude of CIV waspositively correlated to the length of the optic axis. Locations of CIV were scattered in all directions centered on corneal light reflection. Locations of angle kappa and angle alpha distributed mostly in the temporal side of corneal light reflection. Locations of angle alpha were more organized than that of angle kappa. The magnitude of angle kappa significantly decreased after the phacoemulsification. No significant differences were observed between pre- and postoperative angle kappa in orientation, and between pre- and postoperative angle alpha.
Conclusion
The CIV was not related to preoperative angle kappa and angle alpha. Angle kappa may change after the cataract surgery. The distanceof CIV may be greater in cataract patients with longer optic axis.
Impact of Elimination of Preoperative Fasting Requirements for Cataract Surgery Patients
Authors
Daniel C. Terveen, MD
Vance M. Thompson, MD
Methods
This was a prospective, interventional case series of patients undergoing cataract surgery at an independent ambulatory surgery center. All patients had oral anesthesia. Two hundred patients were equally divided between the intervention group, which had no fasting requirement prior to cataract surgery and the control group, which followed the 2011 American Society of Anesthesiologists preoperative fasting guidelines of abstaining from food for 6 hours and clear liquids for 2 hours prior to surgery. The participants completed a satisfaction questionnaire and incidence of PONV was documented.
Results
Two hundred patients were enrolled in the study with surgeries completed by two ophthalmologists. The non-fasting group had significantly higher preoperative satisfaction than the fasting group (Mann-Whitney U test, p=0.002). There was no difference in intraoperative or postoperative satisfaction (p=0.814 and p=0.983 respectively). There was one case of PONV in each group.
Conclusion
Elimination of fasting requirements prior to cataract surgery increased patient preoperative satisfaction compared to recommended fasting guidelines. There were no adverse events attributed to the intervention, no differences in the intraoperative and postoperative satisfaction, and no difference in the incidence of PONV.
Daniel C. Terveen, MD
Vance M. Thompson, MD
Methods
This was a prospective, interventional case series of patients undergoing cataract surgery at an independent ambulatory surgery center. All patients had oral anesthesia. Two hundred patients were equally divided between the intervention group, which had no fasting requirement prior to cataract surgery and the control group, which followed the 2011 American Society of Anesthesiologists preoperative fasting guidelines of abstaining from food for 6 hours and clear liquids for 2 hours prior to surgery. The participants completed a satisfaction questionnaire and incidence of PONV was documented.
Results
Two hundred patients were enrolled in the study with surgeries completed by two ophthalmologists. The non-fasting group had significantly higher preoperative satisfaction than the fasting group (Mann-Whitney U test, p=0.002). There was no difference in intraoperative or postoperative satisfaction (p=0.814 and p=0.983 respectively). There was one case of PONV in each group.
Conclusion
Elimination of fasting requirements prior to cataract surgery increased patient preoperative satisfaction compared to recommended fasting guidelines. There were no adverse events attributed to the intervention, no differences in the intraoperative and postoperative satisfaction, and no difference in the incidence of PONV.
Thermal Pulsations or Conventional Therapy for Meibomian Gland Dysfunction: Impact on Tear Film Metrics & Cataract Surgery Outcomes ?
Author
Rushad C. Shroff, MD
Methods
Prospective Randomized Single Centre interventional Hospital Study Consecutive patients undergoing cataract surgery were recruited. Grading of MGD was performed. Patients with Obstructive MGD were randomized to treatment with LipiFlow (Group 1, n=35) , no intervention (Group 2, n=35) and hot fomentation and antibiotic ointment (Group 3 , n=35). Objective criteria like Schirmers 1,2, TBUT, Meibomian gland dropout area,aberrations,Lipid layer thickness and SPEED score were studied in all the groups before and 3 months after treatment. Analysis was performed using Medcalc software. Statistical tests used were ANOVA and paired T test.
Results
Group 1 (LIPIFLOW group) showed a significant improvement in preoperative and 3 month postoperative values of TBUT {5.91+ 0.5 to 10.39 + 1.5seconds ( p=0.004)}, Lipid layer thickness {67.94 + 5.9 to 80.50 + 7.2 ICU (p=0.04)}, SPEED score {13.63 + 0.8 to 09.44 + 0.8 (p=0.001)} and Meniscus height {0.27 + .03mm to 0.42 + .08 mm (p=0.03)} . Group 2 & 3 did not show a significant improvement in tear film metrics on comparing the pre and postoperative visits. On comparing the 3 groups TBUT (p=0.04), corneal aberrations (p=0.03) and SPEED Score (p=0.001) were significantly better in the Lipiflow group.
Conclusion
Treatment of MGD before Cataract Surgery improves patient satisfaction after cataract surgery. Treatment with LIPIFLOW (J&J) shows benefit over traditional therapy in patients with Moderate MGD. Cataract surgery outcomes are also better with prior treatment of MGD. Further studies and a larger sample size are required to verify the same.
Rushad C. Shroff, MD
Methods
Prospective Randomized Single Centre interventional Hospital Study Consecutive patients undergoing cataract surgery were recruited. Grading of MGD was performed. Patients with Obstructive MGD were randomized to treatment with LipiFlow (Group 1, n=35) , no intervention (Group 2, n=35) and hot fomentation and antibiotic ointment (Group 3 , n=35). Objective criteria like Schirmers 1,2, TBUT, Meibomian gland dropout area,aberrations,Lipid layer thickness and SPEED score were studied in all the groups before and 3 months after treatment. Analysis was performed using Medcalc software. Statistical tests used were ANOVA and paired T test.
Results
Group 1 (LIPIFLOW group) showed a significant improvement in preoperative and 3 month postoperative values of TBUT {5.91+ 0.5 to 10.39 + 1.5seconds ( p=0.004)}, Lipid layer thickness {67.94 + 5.9 to 80.50 + 7.2 ICU (p=0.04)}, SPEED score {13.63 + 0.8 to 09.44 + 0.8 (p=0.001)} and Meniscus height {0.27 + .03mm to 0.42 + .08 mm (p=0.03)} . Group 2 & 3 did not show a significant improvement in tear film metrics on comparing the pre and postoperative visits. On comparing the 3 groups TBUT (p=0.04), corneal aberrations (p=0.03) and SPEED Score (p=0.001) were significantly better in the Lipiflow group.
Conclusion
Treatment of MGD before Cataract Surgery improves patient satisfaction after cataract surgery. Treatment with LIPIFLOW (J&J) shows benefit over traditional therapy in patients with Moderate MGD. Cataract surgery outcomes are also better with prior treatment of MGD. Further studies and a larger sample size are required to verify the same.
Examining the Necessity of Required Preoperative History/Physicals for Cataract Surgery: The Burden on Patients
Authors
Ariana M. Levin, MD
Rachel Simpson, MD, ABO
Methods
This study was a cross-sectional, survey-based study. Optional, anonymous surveys were offered to all patients who presented for a preoperative H&P prior to cataract surgery at the Salt Lake City Veterans Affairs Hospital. Seventy-two patients have been included thus far. Recruitment is ongoing. Patients were asked to report costs (time and monetary) associated with the preoperative H&P, including travel, missed work, and other costs. Patients were also asked to report measures of overall financial wellness.
Results
Our catchment area includes six states: NV, UT, CO, ID, WY, and MT. Median reported time to travel from home to the H&P appointment (one way) was 60 minutes (mean 95; range 15-600 min). Median reported distance was 75 miles (mean 33; range 2-449 mi). Sixteen patients (22%) reported that the patient or family had missed work to attend the appointment. Eight patients (11%) reported that child/pet care had to be paid for. Twenty-two patients (31%) reported that they have “felt concerned about the costs of medical care.” Fourteen patients (19%) reported that they have “filed for bankruptcy.” Seven patients (10%) reported that they have “felt concerned about the need to file for bankruptcy.”
Conclusion
The preoperative H&P puts a financial burden on patients. Prior studies have called into question its value and effectiveness. We suggest that alternatives to the required H&P, including stratifying patients into risk groups and utilizing telemedicine, should be considered in order to decrease the financial burden on patients and institutions.
Ariana M. Levin, MD
Rachel Simpson, MD, ABO
Methods
This study was a cross-sectional, survey-based study. Optional, anonymous surveys were offered to all patients who presented for a preoperative H&P prior to cataract surgery at the Salt Lake City Veterans Affairs Hospital. Seventy-two patients have been included thus far. Recruitment is ongoing. Patients were asked to report costs (time and monetary) associated with the preoperative H&P, including travel, missed work, and other costs. Patients were also asked to report measures of overall financial wellness.
Results
Our catchment area includes six states: NV, UT, CO, ID, WY, and MT. Median reported time to travel from home to the H&P appointment (one way) was 60 minutes (mean 95; range 15-600 min). Median reported distance was 75 miles (mean 33; range 2-449 mi). Sixteen patients (22%) reported that the patient or family had missed work to attend the appointment. Eight patients (11%) reported that child/pet care had to be paid for. Twenty-two patients (31%) reported that they have “felt concerned about the costs of medical care.” Fourteen patients (19%) reported that they have “filed for bankruptcy.” Seven patients (10%) reported that they have “felt concerned about the need to file for bankruptcy.”
Conclusion
The preoperative H&P puts a financial burden on patients. Prior studies have called into question its value and effectiveness. We suggest that alternatives to the required H&P, including stratifying patients into risk groups and utilizing telemedicine, should be considered in order to decrease the financial burden on patients and institutions.
The Role of Macula SD OCT in the Pre-Operative Evaluation of Cataract Surgery
Author
Maria S. Romero, MD
Methods
Prospective consecutive surgical series of eye pre-operative cataract evaluation. Exclusion criteria was any known macular or retinal disease or prior retina treatment. All patients undergoing cataract surgery had preoperative macula SD – OCT and a comprehensive eye exam and 3 months postoperatively
Results
The study compromised 33 patients (42 eyes). Mean age was 73. Of the 42 eyes n=27 had abnormal macular SD- OCT that was not previously diagnosed. Mean pre-operative BCVA was 0.31 Log Mar. The most common findings were epiretinal membrane, vitreous macula traction, RPE hypertrophy, and macular hole. The mean BCVA post-op was 0.07 Log Mar. Only one patient demonstrated differences in the SD OCT at the 3 months postoperative testing which was the result of CME post-op. Of the 42 eyes n=27 eyes had glaucoma, n=9 had diabetes and n=2 had myopia.
Conclusion
From this study we determine that macula SD OCT is a useful screening tool for retinal diseases in the context of cataract surgery. Cataract surgery did not modify the SD OCT findings in the immediate post-operative period. Post-operative visual acuity was not significantly impact by the pre-operative macula SD OCT findings.
Maria S. Romero, MD
Methods
Prospective consecutive surgical series of eye pre-operative cataract evaluation. Exclusion criteria was any known macular or retinal disease or prior retina treatment. All patients undergoing cataract surgery had preoperative macula SD – OCT and a comprehensive eye exam and 3 months postoperatively
Results
The study compromised 33 patients (42 eyes). Mean age was 73. Of the 42 eyes n=27 had abnormal macular SD- OCT that was not previously diagnosed. Mean pre-operative BCVA was 0.31 Log Mar. The most common findings were epiretinal membrane, vitreous macula traction, RPE hypertrophy, and macular hole. The mean BCVA post-op was 0.07 Log Mar. Only one patient demonstrated differences in the SD OCT at the 3 months postoperative testing which was the result of CME post-op. Of the 42 eyes n=27 eyes had glaucoma, n=9 had diabetes and n=2 had myopia.
Conclusion
From this study we determine that macula SD OCT is a useful screening tool for retinal diseases in the context of cataract surgery. Cataract surgery did not modify the SD OCT findings in the immediate post-operative period. Post-operative visual acuity was not significantly impact by the pre-operative macula SD OCT findings.
Low Level Light and Intense Pulsed Light Therapy for the Treatment of Meibomian Gland Disease Prior to Refractive and Cataract Surgery.
Author
Karl G. Stonecipher, MD, ABO
Methods
The author treated patients in a prospective study of LLLT/IPL for treatment of MGD. All patients received complete eye exams with the primary focus on the subjective evaluation of the intervention using the Ocular Surface Disease Index (OSDI) and the objective evaluation of the intervention using Meibomian Gland Expression (MGE) and Tear Break Up Time (TBUT) prior to treatment and 1-3 months after treatment and following surgical intervention.
Results
Prior to intervention the average OSDI score was 44.4. Post treatment that was reduced to 25.4. Prior to intervention the average MGE was 3.63. Post treatment that was reduced to 2.36. The MGE was defined on a 4-point scale with 4 being the inability to express meibum and 0 being normal. The author will further define this scale with a video presentation. Finally, prior to intervention the average TBUT was 3.78 seconds. Post treatment that TBUT was increased to 7.56 seconds. There were no reported adverse events. All patients noted improvement of the MGD with the treatment. Preoperative stabilization and postoperative outcomes of refractive and cataract surgery will be discussed.
Conclusion
The use of LLLT/IPL for the treatment of MGD is beneficial as a primary intervention or secondary intervention in patients who have failed topical and/or systemic therapy. The author will discuss the use of this technology to improve outcomes in refractive and cataract surgery.
Karl G. Stonecipher, MD, ABO
Methods
The author treated patients in a prospective study of LLLT/IPL for treatment of MGD. All patients received complete eye exams with the primary focus on the subjective evaluation of the intervention using the Ocular Surface Disease Index (OSDI) and the objective evaluation of the intervention using Meibomian Gland Expression (MGE) and Tear Break Up Time (TBUT) prior to treatment and 1-3 months after treatment and following surgical intervention.
Results
Prior to intervention the average OSDI score was 44.4. Post treatment that was reduced to 25.4. Prior to intervention the average MGE was 3.63. Post treatment that was reduced to 2.36. The MGE was defined on a 4-point scale with 4 being the inability to express meibum and 0 being normal. The author will further define this scale with a video presentation. Finally, prior to intervention the average TBUT was 3.78 seconds. Post treatment that TBUT was increased to 7.56 seconds. There were no reported adverse events. All patients noted improvement of the MGD with the treatment. Preoperative stabilization and postoperative outcomes of refractive and cataract surgery will be discussed.
Conclusion
The use of LLLT/IPL for the treatment of MGD is beneficial as a primary intervention or secondary intervention in patients who have failed topical and/or systemic therapy. The author will discuss the use of this technology to improve outcomes in refractive and cataract surgery.
Comparison of Toric IOL Prediction Accuracy Using Pentacam, OPD, IOL Master 700 TK and Their Median Measurements.
Authors
Mark K. Lukewich, PhD
Sohel Somani, MD, FRCSC
Eric S. Tam, MD, FRCSC
Hannah H. Chiu, MD, FRCSC
Methods
A prospective cohort study was undertaken. Patients with corneal astigmatism and no other ocular comorbidities that underwent uneventful refractive laser assisted cataract surgery with toric IOL implantation between May 2019 to September 2019 were recruited. A total of 25 eyes from 25 patients were included in this study. The Barrett toric calculator was used to predict preoperative corneal astigmatism using measurements from Pentacam, OPD, IOLM and median measurements from all devices (MM). The prediction error for each method was calculated at postoperative month 1 using the Astigmatism Double Angle Plot Tool developed by Abulafia et al.
Results
Centroid preoperative corneal astigmatism was 0.77D@87° for with the rule (WTR) and 1.38D@2° for against the rule (ATR) eyes. Centroid prediction errors were 0.21D@14°, 0.19D@7°, 0.25D@11°and 0.22D@14° for IOLM, Pentacam, OPD and MM, respectively in WTR astigmatism (p>0.05). In ATR astigmatism, centroid prediction errors were 0.25D@132°, 0.23D@136°, 0.25D@131°and 0.25D@129° for IOLM, Pentacam, OPD and MM, respectively (p>0.05). Prediction errors <0.5D were observed in 69% of calculations using IOLM, OPD and MM, and 77% using Pentacam in WTR eyes (p>0.05). In ATR eyes, 50%, 67%, 42% and 58% of calculations using IOLM, Pentacam, OPD and MM, respectively, had prediction errors <0.5D (p>0.05).
Conclusion
Compared with our previous study where IOLM demonstrated the highest centroid prediction error, IOLM Tk demonstrated similar centroid prediction error with other measurement tools. The incorporation of median measurements from IOLM, Pentacam and OPD into the Barrett toric calculation did not improve calculation accuracy.
Mark K. Lukewich, PhD
Sohel Somani, MD, FRCSC
Eric S. Tam, MD, FRCSC
Hannah H. Chiu, MD, FRCSC
Methods
A prospective cohort study was undertaken. Patients with corneal astigmatism and no other ocular comorbidities that underwent uneventful refractive laser assisted cataract surgery with toric IOL implantation between May 2019 to September 2019 were recruited. A total of 25 eyes from 25 patients were included in this study. The Barrett toric calculator was used to predict preoperative corneal astigmatism using measurements from Pentacam, OPD, IOLM and median measurements from all devices (MM). The prediction error for each method was calculated at postoperative month 1 using the Astigmatism Double Angle Plot Tool developed by Abulafia et al.
Results
Centroid preoperative corneal astigmatism was 0.77D@87° for with the rule (WTR) and 1.38D@2° for against the rule (ATR) eyes. Centroid prediction errors were 0.21D@14°, 0.19D@7°, 0.25D@11°and 0.22D@14° for IOLM, Pentacam, OPD and MM, respectively in WTR astigmatism (p>0.05). In ATR astigmatism, centroid prediction errors were 0.25D@132°, 0.23D@136°, 0.25D@131°and 0.25D@129° for IOLM, Pentacam, OPD and MM, respectively (p>0.05). Prediction errors <0.5D were observed in 69% of calculations using IOLM, OPD and MM, and 77% using Pentacam in WTR eyes (p>0.05). In ATR eyes, 50%, 67%, 42% and 58% of calculations using IOLM, Pentacam, OPD and MM, respectively, had prediction errors <0.5D (p>0.05).
Conclusion
Compared with our previous study where IOLM demonstrated the highest centroid prediction error, IOLM Tk demonstrated similar centroid prediction error with other measurement tools. The incorporation of median measurements from IOLM, Pentacam and OPD into the Barrett toric calculation did not improve calculation accuracy.