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Functional improvement after phacoemulsification cataract surgery12
Functional improvement after phacoemulsification cataract surgery Anne Chang-Godinich, MD, Richard J. Ou, Douglas D. Koch, MD ABSTRACT Purpose: To evaluate subjective functional visual improvement after phacoemulsification and intraocular lens (IOL) implantation and identify patient characteristics and treatment features associated with no functional improvement. Setting: Academic referral practice, Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. Methods: A retrospective review was performed of the surgical results in 106 consecutive eyes of 102 patients who completed the American Society of Cataract and Refractive Surgery (ASCRS) Cataract Data Collection Form© preoperatively and 1 month postoperatively. One surgeon performed all the surgery. The relationship of patient characteristics and treatment features and reported visual function was analyzed using an analysis of variance and the Wilcoxon rank sum and Fisher exact tests. Results: One month postoperatively, all patients demonstrated improved visual acuity. However, 15 patients (14%) reported unimproved or decreased visual function. No statistically significant intergroup difference (P ⬎ .05) was detected in mean preoperative, postoperative, and fellow eye best spectacle-corrected visual acuities or refractive errors; reported severity of preoperative symptoms or satisfaction with vision; reported preoperative daily activity functioning or prevalence of hypertension and diabetes; type of anesthesia, lens material, or wound closure used; intraoperative or postoperative complication rates. However, patients reporting unimproved vision tended to be older and less satisfied with their quality of life and medical care than those reporting improved vision (P ⫽ .02, .03, .01, respectively). Conclusions: Self-reported visual function generally improved after phacoemulsification and IOL implantation; however, some older patients less satisfied with their quality of life and medical care reported no functional improvement despite improved visual acuity. These patients might benefit from an extended preoperative discussion of postoperative expectations. J Cataract Refract Surg 1999; 25: 1226 –1231 © 1999 ASCRS and ESCRS
T
he decision to perform cataract surgery should not be based on visual acuity alone.1 Although cataract surgery yields excellent acuity results, with
Reprint requests to Douglas D. Koch, MD, Cullen Eye Institute, 6565 Fannin, Suite NC 205, Houston, Texas 77030, USA. © 1999 ASCRS and ESCRS Published by Elsevier Science Inc.
95% of patients enjoying visual acuity of 20/40 or better,2 a growing body of outcomes research indicates that self-reported visual function reflects patient satisfaction better than measured visual acuity.3–5 The purpose of this study was to evaluate subjective functional visual improvement after phacoemulsifica0886-3350/99/$–see front matter PII S0886-3350(99)00193-5
FUNCTIONAL IMPROVEMENT AFTER PHACOEMULSIFICATION
tion and intraocular lens (IOL) implantation performed by a single surgeon and to determine patient characteristics and treatment features associated with unimproved visual function.
Patients and Methods Patients The study included 106 eyes of 101 patients who had planned phacoemulsification cataract extraction with IOL implantation and 1 patient who had a planned IOL exchange from September 1994 to December 1996. All patients fully completed the American Society of Cataract and Refractive Surgery (ASCRS) Cataract Data Collection Form© (ACDCF) (Figure 1) preoperatively and 1 month postoperatively (mean 32.7 days; range 19 to 65 days). Surgical Technique Cataract surgery was performed by phacoemulsification through clear corneal (80%) or limbal incisions. All surgeries were performed as outpatient procedures
using topical, peribulbar, general, or retrobulbar anesthesia. Silicone (55%), acrylic, or poly(methyl methacrylate) IOLs were implanted in the posterior chamber except in 1 patient who received an anterior chamber lens because of lack of zonular support. Data Collection Visual Function. The primary outcome variable was reported visual function, as determined by calculating a mean functional impairment score (MFI). This score represents the mean reported impairment level for performing the 13 visual function activities listed on the ACDCF, which was adapted from the questionnaire developed by Brenner et al.6 Preoperative and postoperative mean impairment scores for each eye were calculated based on patient responses. Responses were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1. Unanswered questions or questions answered with “don’t know” responses (91 preoperatively and 43 postoperatively) were withdrawn from tabulation. Thus, a change in the MFI of negative 1 would indicate improved functioning by 1 interval level. All preoperative
Figure 1. (Chang-Godinich) The ASCRS National Ophthalmic Database Library Cataract Data Collection Form (ACDCF). J CATARACT REFRACT SURG—VOL 25, SEPTEMBER 1999
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FUNCTIONAL IMPROVEMENT AFTER PHACOEMULSIFICATION
questionnaires were completed by the patient in the physician’s office. At 1 month, patients were given a spectacle prescription and a copy of the questionnaire, along with a self-addressed, stamped envelope with instructions for mailing. Patients were instructed to complete the form 1 to 2 weeks after obtaining their glasses. Age. Age was determined at the time of the preoperative visit. Visual Acuity. The visual acuity was assessed using LogMAR values of measured Snellen acuity. Counting fingers, hand motion, and light perception were assigned 20/800, 20/1600, and 20/3200 Snellen equivalents, respectively7; no light perception was assigned a LogMAR value of 3.00.8 Refractive Error. The refractive error was determined by manifest refraction and converted to the spherical equivalent. Visual Symptoms. Responses to the 6 symptoms on the ACDCF were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1; “don’t know” responses were withdrawn from tabulation. Satisfaction with Vision and Satisfaction with Medical Care. Patients were asked to rate their satisfaction on a scale from excellent ⫽ 5, good ⫽ 4, fair ⫽ 3, poor ⫽ 2, to very poor ⫽ 1. Satisfaction with vision was asked with respect to best spectacle-corrected visual acuity (BSCVA). Preoperative responses were tabulated. Life Satisfaction. Patients were asked to rate their satisfaction on a scale of 1 to 10, with 10 being the most satisfied. Daily Activity Functioning. Responses to the 3 activities on the ACDCF were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1; “don’t know” responses were withdrawn from tabulation. Driving Status. The driving status was assessed on the ACDCF with a “yes” or “no” response.
Patient Groups For analysis and comparison of outcome measures, 2 groups were identified: the functionally improved group, which had a decreased MFI 1 month postoperatively (n ⫽ 91); the functionally unimproved group, which had an unchanged or increased MFI (n ⫽ 15). Statistical Analysis Intergroup differences in age, baseline and 1 month postoperative visual acuities, refractive errors, and postoperative days were compared using an analysis of variance and the Wilcoxon rank sum test. All other intergroup differences were compared using the Fisher exact test. A P value of less than 0.05 was considered statistically significant.
Results One month postoperatively, 15 patients (14%) reported decreased or unimproved visual function and 91 patients reported improved visual function (Table 1). The improved group included the patient who had a planned IOL exchange and the only patient who received an anterior chamber IOL. The unimproved group included 2 patients whose preoperative and postoperative MFIs indicated “never” impaired, after adjusting for “don’t know” responses. Sex, race, day of postoperative follow-up, first-eye cataract surgery, and eye operated on were not significantly different between the 2 groups (Table 2). All 106 patients demonstrated improved acuity (mean improvement in visual acuity ⫽ ⫺0.34 LogMAR). Logistic regression analysis of both preoperative LogMAR and change in postoperative LogMAR showed no significant predictors of functional improvement. No significant differences existed in mean preoperative, postoperative, or fellow eye BSCVA or preoperative or postoperative spherical equivalents (Table 3).
Table 1. Mean functional impairment score in the 2 patient groups 1 month postoperatively.
Group
Number (%)
Mean MFI (Range) Preoperative
Postoperative
Mean Change in MFI (Range)
Unimproved
15 (14)
1.9 (1.0⫺3.0)
2.4 (1.0⫺3.0)
⫹0.4 ⫾ 0.5 (0.0 to 1.7)
Improved
91 (86)
2.1 (1.1⫺3.0)
1.2 (1.0⫺2.2)
⫺0.9 ⫾ 0.6 (⫺0.1 to ⫺2.0)
MFI ⫽ mean functional impairment
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Table 2. Patient demographics.
Characteristic Sex, men
Unimproved (n ⴝ 15)
Improved (n ⴝ 91)
Number (%)
Number (%)
P Value
5 (33)
33 (36)
.81
Race, white
15 (100)
88 (97)
.48
Day of postoperative follow-up*
36 ⫾ 10
32 ⫾ 6
.38
First-eye cataract surgery
4 (27)
43 (47)
.17
Eye, right
8 (53)
56 (52)
.91
*Mean ⫾ SD
Similarly, there were no statistically significant intergroup differences in severity of preoperative visual symptoms, satisfaction with current vision, level of daily activity functioning, prevalence of diabetes, hypertension, glaucoma, age-related macular degeneration (ARMD), diabetic retinopathy, or previous treatment in the operated eye. There was a trend toward a higher percentage of nondrivers preoperatively in the functionally unimproved group than in the improved group (27% and 4%, respectively; P ⫽ .07). No statistically significant intergroup differences existed in type of lens material, anesthesia, incision, or wound closure used or intraoperative or postoperative complication rates. No postoperative complications were experienced within the functionally unimproved group, while 2 occurred within the functionally improved group. One patient had an increased intraocular pressure of 32 mm Hg, which was thought to be secondary to a steroid response. Another patient with a history of compensated branch retinal vein occlusion had a recurrence of cystoid macular edema. Statistically significant intergroup differences were found in the outcome variables of age and self-reported satisfaction with life and medical care (Table 4). Functionally unimproved patients tended to be older and slightly less satisfied with their life and medical care.
Discussion This retrospective analysis of patient interviews and clinical data for 106 eyes operated on by 1 surgeon indicated that self-reported visual function generally improved 1 month after uneventful phacoemulsification
cataract surgery; however, a small number of patients reported no functional improvement despite improved Snellen acuity. Our finding that postoperative improvement in acuity was not always associated with reported functional improvement is consistent with a report by Steinberg et al.3 In their prospective analysis of 552 patients having cataract surgery (the Cataract PORT study), they found that the relationship between change in visual acuity and reported visual function 4 months postoperatively was not linear. The association between older age and lack of reported functional improvement in our patients corroborates the findings of Schein et al.9 In the same 552 patients, they found that a preoperative age of 75 years or older was associated with an increased likelihood of not improving on at least l of the 3 outcome measures of visual acuity, symptom score, and reported functional impairment (VF-14). In our study, the unimproved patient group was less satisfied with quality of life and medical care. Schein et al.9 reported a significant association between unimproved visual function and ocular comorbidity (defined as glaucoma, macular degeneration, or diabetic retinopathy) and preoperative cataract symptom scores. Mangione et al.’s10 model for predicting improvement in visual function following cataract surgery has 5 predictive factors: younger age, poorer baseline functional status, and, to lesser degrees, posterior subcapsular cataract and absence of ARMD or diabetes. Although we found no significant intergroup differences in the prevalence of hypertension, diabetes, diabetic retinopathy, glaucoma, or ARMD, we surveyed patients only for the presence of these 5 conditions and a history of eye treatment but gathered no data on the severity of ocular or systemic disease. Therefore, it is possible that our unimproved group had certain distinguishing ocular or systemic comorbidities that were not detected by our methodology. A possible related explanation for lack of reported improvement might be unrealistic expectations of the potential impact of medical treatments and interventions on daily function. In a prospective study of 164 patients aged 70 years and above, Elam et al.11 found that improved function 1 year after cataract surgery was determined in part by the patient’s change in mental status in addition to the change in visual acuity. Patients with little improvement in mental status after cataract surgery experienced little improvement
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Table 3. Preoperative and postoperative BSCVA and spherical equivalent. Feature
Unimproved (n ⴝ 15)
Improved (n ⴝ 91)
P Value
LogMAR improvement, mean (range)
⫺0.33 (⫺0.08 to ⫺0.90)
⫺0.34 (0.00 to ⫺1.60)
—
20/62 (20/30 to 800)
20/54 (20/20 to 800)
.36
Visual acuity
Preoperative, mean (range) Postoperative, mean (range)
20/29 (20/20 to 100)
20/24 (20/20 to 125)
.1
Fellow eye, mean (range)
20/32 (20/20 to 125)
20/34 (20/20 to NLP)
.89
Preoperative, mean ⫾ SD
⫺0.78 ⫾ 2.73
⫺1.12 ⫾ 2.55
.64
Postoperative, mean ⫾ SD
⫺0.53 ⫾ 0.42
⫺0.52 ⫾ 0.65
.96
Spherical equivalent (operative eye)
BSCVA ⫽ best spectacle-corrected visual acuity; NLP ⫽ no light perception
in reported function. Tielsch et al.12 reported that the Cataract PORT patients’ preoperative expectations of the impact of cataract surgery were very high. In patients aged 75 years and older and those with ocular comorbidity, the difference between expected and actual postoperative functioning was greater than in younger patients and those without ocular comorbidity. Older, sicker patients might thus have high expectations of the benefits of cataract surgery, when in reality other conditions account for most of the restrictions in their daily activities. We did find a trend toward a greater percentage of preoperative nondrivers in the unimproved than in the improved group (P ⫽ .07). In a prospective study of 208 Swedish cataract surgery patients, Mo¨nestam and Wachtmeister13 emphasized the importance of evaluating functional driving impairment during preoperative cataract assessment. They found that visual problems Table 4. Features associated with unimproved visual function. Unimproved Improved Mean Mean (SD) (SD)
Feature Age
76.7 (7.5)
71.1 (14)
30–49
0
6
50–59
1
8
60–69
1
22
70–79
9
39
80–89
3
15
90–100
1
1
Satisfaction with life* Satisfaction with care
†
P Value
7.8 (3.1)
8.8 (1.4)
.03
4.6 (0.6)
4.9 (0.3)
.01
*Self-rated from 1 (worst) to 10 (best) preoperatively † Self-rated from 1 (very poor) to 5 (excellent) preoperatively
1230
.02
while driving decreased from 82% before to 5% after cataract surgery, while the number of patients driving with a visual acuity below Swedish licensing requirements decreased from 23% to 4%. This issue might also be related to unrealistic expectations. Some nondriving cataract patients assume that cataract surgery will restore their capacity to drive, when the limiting factors are actually nonocular. A larger study is needed to evaluate this issue. To our knowledge, this is the first report to examine the relationship between type of anesthesia, IOL material, and incision and the reported postoperative change in visual function. We found no statistically significant intergroup difference in any of these parameters, although there was a trend toward more frequent topical anesthesia use in the unimproved group (P ⫽ .07). Again, a larger study is needed to evaluate possible significance. In summary, our analysis of 106 eyes 1 month after successful phacoemulsification cataract surgery indicates that self-reported visual function generally improves. However, a small number of patients who tend to be older and less satisfied with life and medical care may report no functional improvement despite attaining improved Snellen acuity. These patients may benefit from an extended preoperative discussion of expected postoperative benefits. Limitations of our study include the retrospective design, a modestly sized patient database, and a short follow-up. A larger prospective study is needed to validate the significance of the intergroup differences. However, the preliminary findings suggest that the preoperative evaluation should include a discussion of patients’ postoperative functional expectations. A more comprehensive evaluation of the role of patients’
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social factors and activities, including marital status, education and income levels, employment, and hobbies, might also help to identify patients who will not report functional benefit from technically successful cataract surgery.
9.
10.
References 1. Lee PP, Kamberg CJ, Hilborne LH, et al. Cataract Surgery: a Literature Review and Ratings of Appropriateness and Cruciality. Santa Monica, CA, Rand, 1993 2. Powe NR, Schein OD, Gieser SC, et al. Synthesis of the literature on visual acuity and complications following cataract extraction with intraocular lens implantation. Arch Ophthalmol 1994; 112:239 –252; correction p 889 3. Steinberg EP, Tielsch JM, Schein OD, et al. National study of cataract surgery outcomes; variation in 4-month postoperative outcomes as reflected in multiple outcome measures. Ophthalmology 1994; 101:1131–1141 4. Mangione CM, Phillips RS, Lawrence MG, et al. Improved visual function and attenuation of declines in health-related quality of life after cataract extraction. Arch Ophthalmol 1994; 112:1419 –1425 5. Uusitalo RJ, Tarkkanen A. Outcomes of small incision cataract surgery. J Cataract Refract Surg 1998; 24:212– 221 6. Brenner MH, Curbow B, Javitt JC, et al. Vision change and quality of life in the elderly; response to cataract surgery and treatment of other chronic ocular conditions. Arch Ophthalmol 1993; 111:680 – 685 7. Javitt JC, Brenner MH, Curbow B, et al. Outcomes of cataract surgery; improvement in visual acuity and subjective visual function after surgery in the first, second, and both eyes. Arch Ophthalmol 1993; 111:686 – 691 8. Hartz AJ, Burton TC, Gottlieb MS, et al. Outcomes and
11.
12.
13.
cost analysis of scheduled versus emergency scleral buckling surgery. Trans Am Ophthalmol Soc 1991; 89:271– 283 Schein OD, Steinberg EP, Cassard SD, et al. Predictors of outcome in patients who underwent cataract surgery. Ophthalmology 1995; 102:817– 823 Mangione CM, Orav EJ, Lawrence MG, et al. Prediction of visual function after cataract surgery; a prospectively validated model. Arch Ophthalmol 1995; 113: 1305– 1311 Elam JT, Graney MJ, Applegate WB, et al. Functional outcome one year following cataract surgery in elderly persons. J Gerontol 1988; 43:M122–M126 Tielsch JM, Steinberg, EP, Cassard SD, et al. Preoperative functional expectations and postoperative outcomes among patients undergoing first eye cataract surgery. Arch Ophthalmol 1995; 113:1312–1318 Mo¨nestam E, Wachtmeister L. Impact of cataract surgery on car driving: a population based study in Sweden. Br J Ophthalmol 1997; 81:16 –22
Accepted for publication March 9, 1999. From the Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. Presented in part at the annual meeting of the Association for Research in Vision and Ophthalmology, Fort Lauderdale, Florida, USA, May 1998. Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York; the Baylor Ophthalmology Resident Research Fund, Houston, Texas; and a student fellowship from Fight for Sight–Prevent Blindness America, Schaumburg, Illinois, USA. None of the authors has a financial interest in any product mentioned. Mark Munsell, MS, and Myrna Khan of Applied Logics, Inc., provided consultation for the statistical analysis.
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T
he decision to perform cataract surgery should not be based on visual acuity alone.1 Although cataract surgery yields excellent acuity results, with
Reprint requests to Douglas D. Koch, MD, Cullen Eye Institute, 6565 Fannin, Suite NC 205, Houston, Texas 77030, USA. © 1999 ASCRS and ESCRS Published by Elsevier Science Inc.
95% of patients enjoying visual acuity of 20/40 or better,2 a growing body of outcomes research indicates that self-reported visual function reflects patient satisfaction better than measured visual acuity.3–5 The purpose of this study was to evaluate subjective functional visual improvement after phacoemulsifica0886-3350/99/$–see front matter PII S0886-3350(99)00193-5
FUNCTIONAL IMPROVEMENT AFTER PHACOEMULSIFICATION
tion and intraocular lens (IOL) implantation performed by a single surgeon and to determine patient characteristics and treatment features associated with unimproved visual function.
Patients and Methods Patients The study included 106 eyes of 101 patients who had planned phacoemulsification cataract extraction with IOL implantation and 1 patient who had a planned IOL exchange from September 1994 to December 1996. All patients fully completed the American Society of Cataract and Refractive Surgery (ASCRS) Cataract Data Collection Form© (ACDCF) (Figure 1) preoperatively and 1 month postoperatively (mean 32.7 days; range 19 to 65 days). Surgical Technique Cataract surgery was performed by phacoemulsification through clear corneal (80%) or limbal incisions. All surgeries were performed as outpatient procedures
using topical, peribulbar, general, or retrobulbar anesthesia. Silicone (55%), acrylic, or poly(methyl methacrylate) IOLs were implanted in the posterior chamber except in 1 patient who received an anterior chamber lens because of lack of zonular support. Data Collection Visual Function. The primary outcome variable was reported visual function, as determined by calculating a mean functional impairment score (MFI). This score represents the mean reported impairment level for performing the 13 visual function activities listed on the ACDCF, which was adapted from the questionnaire developed by Brenner et al.6 Preoperative and postoperative mean impairment scores for each eye were calculated based on patient responses. Responses were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1. Unanswered questions or questions answered with “don’t know” responses (91 preoperatively and 43 postoperatively) were withdrawn from tabulation. Thus, a change in the MFI of negative 1 would indicate improved functioning by 1 interval level. All preoperative
Figure 1. (Chang-Godinich) The ASCRS National Ophthalmic Database Library Cataract Data Collection Form (ACDCF). J CATARACT REFRACT SURG—VOL 25, SEPTEMBER 1999
1227
FUNCTIONAL IMPROVEMENT AFTER PHACOEMULSIFICATION
questionnaires were completed by the patient in the physician’s office. At 1 month, patients were given a spectacle prescription and a copy of the questionnaire, along with a self-addressed, stamped envelope with instructions for mailing. Patients were instructed to complete the form 1 to 2 weeks after obtaining their glasses. Age. Age was determined at the time of the preoperative visit. Visual Acuity. The visual acuity was assessed using LogMAR values of measured Snellen acuity. Counting fingers, hand motion, and light perception were assigned 20/800, 20/1600, and 20/3200 Snellen equivalents, respectively7; no light perception was assigned a LogMAR value of 3.00.8 Refractive Error. The refractive error was determined by manifest refraction and converted to the spherical equivalent. Visual Symptoms. Responses to the 6 symptoms on the ACDCF were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1; “don’t know” responses were withdrawn from tabulation. Satisfaction with Vision and Satisfaction with Medical Care. Patients were asked to rate their satisfaction on a scale from excellent ⫽ 5, good ⫽ 4, fair ⫽ 3, poor ⫽ 2, to very poor ⫽ 1. Satisfaction with vision was asked with respect to best spectacle-corrected visual acuity (BSCVA). Preoperative responses were tabulated. Life Satisfaction. Patients were asked to rate their satisfaction on a scale of 1 to 10, with 10 being the most satisfied. Daily Activity Functioning. Responses to the 3 activities on the ACDCF were qualified as always ⫽ 3, sometimes ⫽ 2, and never ⫽ 1; “don’t know” responses were withdrawn from tabulation. Driving Status. The driving status was assessed on the ACDCF with a “yes” or “no” response.
Patient Groups For analysis and comparison of outcome measures, 2 groups were identified: the functionally improved group, which had a decreased MFI 1 month postoperatively (n ⫽ 91); the functionally unimproved group, which had an unchanged or increased MFI (n ⫽ 15). Statistical Analysis Intergroup differences in age, baseline and 1 month postoperative visual acuities, refractive errors, and postoperative days were compared using an analysis of variance and the Wilcoxon rank sum test. All other intergroup differences were compared using the Fisher exact test. A P value of less than 0.05 was considered statistically significant.
Results One month postoperatively, 15 patients (14%) reported decreased or unimproved visual function and 91 patients reported improved visual function (Table 1). The improved group included the patient who had a planned IOL exchange and the only patient who received an anterior chamber IOL. The unimproved group included 2 patients whose preoperative and postoperative MFIs indicated “never” impaired, after adjusting for “don’t know” responses. Sex, race, day of postoperative follow-up, first-eye cataract surgery, and eye operated on were not significantly different between the 2 groups (Table 2). All 106 patients demonstrated improved acuity (mean improvement in visual acuity ⫽ ⫺0.34 LogMAR). Logistic regression analysis of both preoperative LogMAR and change in postoperative LogMAR showed no significant predictors of functional improvement. No significant differences existed in mean preoperative, postoperative, or fellow eye BSCVA or preoperative or postoperative spherical equivalents (Table 3).
Table 1. Mean functional impairment score in the 2 patient groups 1 month postoperatively.
Group
Number (%)
Mean MFI (Range) Preoperative
Postoperative
Mean Change in MFI (Range)
Unimproved
15 (14)
1.9 (1.0⫺3.0)
2.4 (1.0⫺3.0)
⫹0.4 ⫾ 0.5 (0.0 to 1.7)
Improved
91 (86)
2.1 (1.1⫺3.0)
1.2 (1.0⫺2.2)
⫺0.9 ⫾ 0.6 (⫺0.1 to ⫺2.0)
MFI ⫽ mean functional impairment
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Table 2. Patient demographics.
Characteristic Sex, men
Unimproved (n ⴝ 15)
Improved (n ⴝ 91)
Number (%)
Number (%)
P Value
5 (33)
33 (36)
.81
Race, white
15 (100)
88 (97)
.48
Day of postoperative follow-up*
36 ⫾ 10
32 ⫾ 6
.38
First-eye cataract surgery
4 (27)
43 (47)
.17
Eye, right
8 (53)
56 (52)
.91
*Mean ⫾ SD
Similarly, there were no statistically significant intergroup differences in severity of preoperative visual symptoms, satisfaction with current vision, level of daily activity functioning, prevalence of diabetes, hypertension, glaucoma, age-related macular degeneration (ARMD), diabetic retinopathy, or previous treatment in the operated eye. There was a trend toward a higher percentage of nondrivers preoperatively in the functionally unimproved group than in the improved group (27% and 4%, respectively; P ⫽ .07). No statistically significant intergroup differences existed in type of lens material, anesthesia, incision, or wound closure used or intraoperative or postoperative complication rates. No postoperative complications were experienced within the functionally unimproved group, while 2 occurred within the functionally improved group. One patient had an increased intraocular pressure of 32 mm Hg, which was thought to be secondary to a steroid response. Another patient with a history of compensated branch retinal vein occlusion had a recurrence of cystoid macular edema. Statistically significant intergroup differences were found in the outcome variables of age and self-reported satisfaction with life and medical care (Table 4). Functionally unimproved patients tended to be older and slightly less satisfied with their life and medical care.
Discussion This retrospective analysis of patient interviews and clinical data for 106 eyes operated on by 1 surgeon indicated that self-reported visual function generally improved 1 month after uneventful phacoemulsification
cataract surgery; however, a small number of patients reported no functional improvement despite improved Snellen acuity. Our finding that postoperative improvement in acuity was not always associated with reported functional improvement is consistent with a report by Steinberg et al.3 In their prospective analysis of 552 patients having cataract surgery (the Cataract PORT study), they found that the relationship between change in visual acuity and reported visual function 4 months postoperatively was not linear. The association between older age and lack of reported functional improvement in our patients corroborates the findings of Schein et al.9 In the same 552 patients, they found that a preoperative age of 75 years or older was associated with an increased likelihood of not improving on at least l of the 3 outcome measures of visual acuity, symptom score, and reported functional impairment (VF-14). In our study, the unimproved patient group was less satisfied with quality of life and medical care. Schein et al.9 reported a significant association between unimproved visual function and ocular comorbidity (defined as glaucoma, macular degeneration, or diabetic retinopathy) and preoperative cataract symptom scores. Mangione et al.’s10 model for predicting improvement in visual function following cataract surgery has 5 predictive factors: younger age, poorer baseline functional status, and, to lesser degrees, posterior subcapsular cataract and absence of ARMD or diabetes. Although we found no significant intergroup differences in the prevalence of hypertension, diabetes, diabetic retinopathy, glaucoma, or ARMD, we surveyed patients only for the presence of these 5 conditions and a history of eye treatment but gathered no data on the severity of ocular or systemic disease. Therefore, it is possible that our unimproved group had certain distinguishing ocular or systemic comorbidities that were not detected by our methodology. A possible related explanation for lack of reported improvement might be unrealistic expectations of the potential impact of medical treatments and interventions on daily function. In a prospective study of 164 patients aged 70 years and above, Elam et al.11 found that improved function 1 year after cataract surgery was determined in part by the patient’s change in mental status in addition to the change in visual acuity. Patients with little improvement in mental status after cataract surgery experienced little improvement
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FUNCTIONAL IMPROVEMENT AFTER PHACOEMULSIFICATION
Table 3. Preoperative and postoperative BSCVA and spherical equivalent. Feature
Unimproved (n ⴝ 15)
Improved (n ⴝ 91)
P Value
LogMAR improvement, mean (range)
⫺0.33 (⫺0.08 to ⫺0.90)
⫺0.34 (0.00 to ⫺1.60)
—
20/62 (20/30 to 800)
20/54 (20/20 to 800)
.36
Visual acuity
Preoperative, mean (range) Postoperative, mean (range)
20/29 (20/20 to 100)
20/24 (20/20 to 125)
.1
Fellow eye, mean (range)
20/32 (20/20 to 125)
20/34 (20/20 to NLP)
.89
Preoperative, mean ⫾ SD
⫺0.78 ⫾ 2.73
⫺1.12 ⫾ 2.55
.64
Postoperative, mean ⫾ SD
⫺0.53 ⫾ 0.42
⫺0.52 ⫾ 0.65
.96
Spherical equivalent (operative eye)
BSCVA ⫽ best spectacle-corrected visual acuity; NLP ⫽ no light perception
in reported function. Tielsch et al.12 reported that the Cataract PORT patients’ preoperative expectations of the impact of cataract surgery were very high. In patients aged 75 years and older and those with ocular comorbidity, the difference between expected and actual postoperative functioning was greater than in younger patients and those without ocular comorbidity. Older, sicker patients might thus have high expectations of the benefits of cataract surgery, when in reality other conditions account for most of the restrictions in their daily activities. We did find a trend toward a greater percentage of preoperative nondrivers in the unimproved than in the improved group (P ⫽ .07). In a prospective study of 208 Swedish cataract surgery patients, Mo¨nestam and Wachtmeister13 emphasized the importance of evaluating functional driving impairment during preoperative cataract assessment. They found that visual problems Table 4. Features associated with unimproved visual function. Unimproved Improved Mean Mean (SD) (SD)
Feature Age
76.7 (7.5)
71.1 (14)
30–49
0
6
50–59
1
8
60–69
1
22
70–79
9
39
80–89
3
15
90–100
1
1
Satisfaction with life* Satisfaction with care
†
P Value
7.8 (3.1)
8.8 (1.4)
.03
4.6 (0.6)
4.9 (0.3)
.01
*Self-rated from 1 (worst) to 10 (best) preoperatively † Self-rated from 1 (very poor) to 5 (excellent) preoperatively
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.02
while driving decreased from 82% before to 5% after cataract surgery, while the number of patients driving with a visual acuity below Swedish licensing requirements decreased from 23% to 4%. This issue might also be related to unrealistic expectations. Some nondriving cataract patients assume that cataract surgery will restore their capacity to drive, when the limiting factors are actually nonocular. A larger study is needed to evaluate this issue. To our knowledge, this is the first report to examine the relationship between type of anesthesia, IOL material, and incision and the reported postoperative change in visual function. We found no statistically significant intergroup difference in any of these parameters, although there was a trend toward more frequent topical anesthesia use in the unimproved group (P ⫽ .07). Again, a larger study is needed to evaluate possible significance. In summary, our analysis of 106 eyes 1 month after successful phacoemulsification cataract surgery indicates that self-reported visual function generally improves. However, a small number of patients who tend to be older and less satisfied with life and medical care may report no functional improvement despite attaining improved Snellen acuity. These patients may benefit from an extended preoperative discussion of expected postoperative benefits. Limitations of our study include the retrospective design, a modestly sized patient database, and a short follow-up. A larger prospective study is needed to validate the significance of the intergroup differences. However, the preliminary findings suggest that the preoperative evaluation should include a discussion of patients’ postoperative functional expectations. A more comprehensive evaluation of the role of patients’
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social factors and activities, including marital status, education and income levels, employment, and hobbies, might also help to identify patients who will not report functional benefit from technically successful cataract surgery.
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References 1. Lee PP, Kamberg CJ, Hilborne LH, et al. Cataract Surgery: a Literature Review and Ratings of Appropriateness and Cruciality. Santa Monica, CA, Rand, 1993 2. Powe NR, Schein OD, Gieser SC, et al. Synthesis of the literature on visual acuity and complications following cataract extraction with intraocular lens implantation. Arch Ophthalmol 1994; 112:239 –252; correction p 889 3. Steinberg EP, Tielsch JM, Schein OD, et al. National study of cataract surgery outcomes; variation in 4-month postoperative outcomes as reflected in multiple outcome measures. Ophthalmology 1994; 101:1131–1141 4. Mangione CM, Phillips RS, Lawrence MG, et al. Improved visual function and attenuation of declines in health-related quality of life after cataract extraction. Arch Ophthalmol 1994; 112:1419 –1425 5. Uusitalo RJ, Tarkkanen A. Outcomes of small incision cataract surgery. J Cataract Refract Surg 1998; 24:212– 221 6. Brenner MH, Curbow B, Javitt JC, et al. Vision change and quality of life in the elderly; response to cataract surgery and treatment of other chronic ocular conditions. Arch Ophthalmol 1993; 111:680 – 685 7. Javitt JC, Brenner MH, Curbow B, et al. Outcomes of cataract surgery; improvement in visual acuity and subjective visual function after surgery in the first, second, and both eyes. Arch Ophthalmol 1993; 111:686 – 691 8. Hartz AJ, Burton TC, Gottlieb MS, et al. Outcomes and
11.
12.
13.
cost analysis of scheduled versus emergency scleral buckling surgery. Trans Am Ophthalmol Soc 1991; 89:271– 283 Schein OD, Steinberg EP, Cassard SD, et al. Predictors of outcome in patients who underwent cataract surgery. Ophthalmology 1995; 102:817– 823 Mangione CM, Orav EJ, Lawrence MG, et al. Prediction of visual function after cataract surgery; a prospectively validated model. Arch Ophthalmol 1995; 113: 1305– 1311 Elam JT, Graney MJ, Applegate WB, et al. Functional outcome one year following cataract surgery in elderly persons. J Gerontol 1988; 43:M122–M126 Tielsch JM, Steinberg, EP, Cassard SD, et al. Preoperative functional expectations and postoperative outcomes among patients undergoing first eye cataract surgery. Arch Ophthalmol 1995; 113:1312–1318 Mo¨nestam E, Wachtmeister L. Impact of cataract surgery on car driving: a population based study in Sweden. Br J Ophthalmol 1997; 81:16 –22
Accepted for publication March 9, 1999. From the Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, USA. Presented in part at the annual meeting of the Association for Research in Vision and Ophthalmology, Fort Lauderdale, Florida, USA, May 1998. Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York; the Baylor Ophthalmology Resident Research Fund, Houston, Texas; and a student fellowship from Fight for Sight–Prevent Blindness America, Schaumburg, Illinois, USA. None of the authors has a financial interest in any product mentioned. Mark Munsell, MS, and Myrna Khan of Applied Logics, Inc., provided consultation for the statistical analysis.
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