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Intraoperative Floppy Iris Syndrome
Letters to the Editor illumination and refraction area, patient volume, lack of patient comprehension, and difficulties in data recovery. RENGARAJ VENKATESH, MD Pondicherry, India References 1. Gogate PM, Kulkarni SR, Krishnaiah S, et al. Safety and efficacy of phacoemulsification compared with manual small incision cataract surgery by a randomized controlled clinical trial. Ophthalmology 2005;112:869 –74. 2. Muralikrishnan R, Venkatesh R, Prajna NV, Frick KD. Economic cost of cataract surgery procedures in an established eye care centre in southern India. Ophthalmic Epidemiol 2004;11:369 – 80. 3. Gogate PM, Deshpande M, Wormald RP, et al. Extracapsular cataract surgery compared with manual small incision cataract surgery in community eye care setting in western India: a randomised controlled trial. Br J Ophthalmol 2003;87:667–72. 4. Venkatesh R, Muralikrishnan R, Balent LC, et al. Outcomes of high volume cataract surgeries in a developing country. Br J Ophthalmol 2005;89:1079 – 83. 5. Venkatesh R, Das MR, Prashanth S, Muralikrishnan R. Manual small incision cataract surgery in eyes with white cataracts. Indian J Ophthalmol 2005;53:173– 6.
Author reply Dear Editor: Dr Venkatesh makes a valid observation that the uncorrected visual acuity results for manual small-incision cataract surgery (SICS) differ for the trial comparing it with conventional extracapsular cataract extraction (ECCE) in 20011 and that comparing it with phacoemulsification in 2003.2 The former had patients recruited from both the base hospital and the peripheral camps, whereas the latter had only outpatients from the base hospital. But the refraction in the peripheral camps was determined by trained ophthalmic assistants or optometrists in primary health centers with a refraction room. The difference in the results of the 2 trials also may have been due to surgeon learning curves. The 4 surgeons participating in the phacoemusification versus manual SICS trial were more experienced in 2003 than they were in 2001 for the same technique when it was being compared with conventional ECCE. I believe that manual SICS is very dependent on surgeon skill for its excellent result, and though it is easier for an ECCE trained surgeon, the learning curve is nonetheless significant. I appreciate Dr Venkatesh’s interest in this topic. His institution, the Aravind Eye Hospital, perhaps does more manual SICS surgery than any other in the world. PARIKSHIT GOGATE Pune, India References 1. Gogate PM, Deshpande M, Wormald RP, et al. Extracapsular cataract surgery compared with manual small incision cataract surgery in a community eye care setting in western India: a randomized control trial. Br J Ophthalmol 2003;87:667–72. 2. Gogate PM, Kulkarni SR, Krishnaiah S, et al. Safety and efficacy of phacoemulcification compared with manual small incision cataract surgery by a randomized control trial. Ophthalmology 2005;112:869 –74.
Intraoperative Floppy Iris Syndrome Dear Editor: Schwinn and Afshari have provided an interesting insight into the understanding of intraoperative floppy iris syndrome (IFIS).1 We share our experience concerning IFIS associated with doxazosin use. The authors propose that, in cases of IFIS associated with the other ␣1-adrenoceptor receptor antagonists, ophthalmologists might either monitor drug levels preoperatively or stop all these medications before cataract surgery. Our patient with IFIS associated with systemic doxazosin may represent a less severe form of the syndrome. We carried out right phacoemulsification surgery on a 70-year-old man. At the start of surgery, the pupil was well dilated at 7 mm. During the capsulorrhexis stage, the iris edges continually fluttered and became increasingly mobile with gradual pupillary miosis. Sodium hyaluronate 2.3% (Healon5, Advanced Medical Optics, Inc., Santa Ana, CA) was used effectively to stabilize the iris. The iris edges were mobile during cataract removal; however, sodium hyaluronate 2.3% was effective in maintaining a pupil size of around 5 mm. A high-vacuum phaco-chop technique (duallinear mode) was used to remove the cataractous lens within the capsular bag. This strategy allowed sodium hyaluronate 2.3% to remain in the anterior chamber and stabilize any iris movements anteriorly due to fluid currents in the posterior chamber. This method reduced the IFIS to mild iris rippling around the pupillary ruff, and we did not encounter any later problems with progressive miosis. Eleven months previously, the fellow eye had cataract surgery at a different center, and this was complicated by intraoperative miosis and IFIS. Technical problems were encountered associated with a floppy iris. Iris retractors were used mechanically to stretch the pupil; however, this was inadequate. A pars plana vitrectomy approach was required later to remove cortical matter trapped behind the lens implant optic. After a medical consultation postoperatively, the patient was reported to have been taking oral doxazosin 4 mg once daily for the treatment of hypertension over a 3-year period. In retrospect, the surgical findings of the case were consistent with a diagnosis of IFIS2 associated with chronic doxazosin use. Doxazosin is a nonselective ␣1-adrenoceptor receptor blocker and may have selective ␣1A-adrenoceptor receptor activity.3 This drug appears to induce iris muscle relaxation, similar to tamsulosin, but may result in a less severe form of IFIS. The dose of doxazosin is adjusted based on the blood pressure (BP) response and side effect profile of the individual. We observed a mild form of IFIS with a patient taking 4 mg over a long period. To determine a plasma level that does not cause IFIS, a large prospective clinical study would be needed. At present, a plasma level of doxazosin that would not increase the risk of IFIS is not known. However, the rate of IFIS may vary tremendously across patients who have the same drug level. On a more practical level, if ophthalmologists choose to withdraw the drug (doxazosin or tamsulosin), the elimination period for the drug may be monitored by
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Ophthalmology Volume 113, Number 10, October 2006 observing the BP and/or for the recurrence of urinary symptoms. No agreed-to preoperative recommendations currently exist for patients on doxazosin therapy for hypertension undergoing cataract surgery. There is a theoretical risk of rebound hypertension after sudden cessation of therapy, but so far we are not aware of reports in the literature.4 ␣1adrenoceptor receptor antagonists, such as tamsulosin and doxazosin, reduce the risk of acute urinary retention by half, to ⬍5%. Withdrawal of tamsulosin in patients with mild or moderate benign prostatic hyperplasia symptoms is unlikely to be complicated by acute urinary retention.5 Acute urinary retention may recur after tamsulosin withdrawal in patients with severe benign prostatic hyperplasia. Patients with severe benign prostatic hyperplasia and high risk of acute urinary retention are not generally on long-term ␣1-adrenoceptor receptor medical therapy. The manufacturer suggests safely stopping tamsulosin therapy 2 weeks before cataract surgery (personal communication, 2006). Patients may continue doxazosin treatment before cataract surgery; however, ophthalmologists must anticipate IFIS. Our experience of using sodium hyaluronate 2.3% and a high-vacuum phaco-chop technique allowed safe surgery to be performed in this case. The risks of rebound hypertension and acute retention may not be a significant management problem around the time of cataract surgery.4,5 However, any alterations to ␣-blocker regimens should be made in discussion with our urology, cardiology, and general practice colleagues. We agree with the current advice for ophthalmologists1,2— namely, that a careful medical and drug history be taken by the clinician and nursing staff during the preoperative assessment for cataract surgery. A risk profile for male and female patients taking ␣1-adrenoceptor receptor antagonists for hypertension and/or urinary tract disorders may need to be discussed with the patient before consent for cataract surgery is obtained. MAHIUL M. K. MUQIT MITCH J. MENAGE Leeds, United Kingdom References 1. Schwinn DA, Afshari NA. ␣1-adrenergic antagonists and floppy iris syndrome: tip of the iceberg? Ophthalmology 2005; 112:2059 – 60. 2. Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. J Cataract Refract Surg 2005;31: 664 –73. 3. Yono M, Foster HE Jr, Shin D, et al. Doxazosin-induced up-regulation of alpha 1A-adrenoceptor mRNA in the rat lower urinary tract. Can J Physiol Pharmacol 2004;82:872– 8. 4. Takata Y, Yoshizumi T, Ito Y, et al. Effect of administration and withdrawal of doxazosin on ambulatory blood pressure in patients with essential hypertension. Angiology 1995;46:11– 8. 5. Barkin J, Guimaraes M, Jacobi G, et al. Alpha-blocker therapy can be withdrawn in the majority of men following initial combination therapy with the dual 5alpha-reductase inhibitor dutasteride. Eur Urol 2003;44:461– 6.
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Author reply Dear Editor: Drs Muqit and Menage suggest that intraoperative floppy iris syndrome may present as a spectrum of disease, from mild (as in their patient) to more clinically significant. Further, they document that intraoperative floppy iris syndrome can result from a spectrum of ␣1-adrenergic receptor antagonist drugs because their patient was taking doxazosin before surgery, whereas original reports centered around tamsulosin. They agree that there should be heightened awareness during preoperative physical examinations to the use of ␣1-adrenergic receptor antagonist drugs. It is important to note that a recently published study provides useful data with regard to ␣1-adrenergic receptor antagonists and iris biology.1 The study demonstrates that all commercially available ␣1-adrenergic receptor blockers (alfuzosin, doxazosin, naftopidil, tamsulosin, and terazosin) induce miosis in clinically relevant concentrations (defined by specific urologic effects), and that these effects are fully reversed within 8 hours of IV administration. This suggests that iris effects due to ␣1-adrenergic receptor antagonists would be minimized if such drugs were discontinued 2 to 3 days before surgery or, more conservatively, 1 to 2 weeks, given that the study was performed in albino rabbits and pigment effects remain unknown. As noted in our article, it should be remembered that intraoperative floppy iris syndrome may occur with other drugs and clinical disease entities, so the possible symptoms of floppy iris may remain in this elderly population even after ␣1-adrenergic receptor antagonists are eliminated as the cause. DEBRA A. SCHWINN, MD NATALIE A. AFSHARI, MD Durham, North Carolina Reference 1. Michel MC, Okutsu H, Noguchi Y, et al. In vivo studies on the effects of alpha1-adrenoceptor antagonists on pupil diameter and urethral tone in rabbits. Naunyn Schmiedebergs Arch Pharmacol 2006;372:346 –53.
Visual Sensations during Vitrectomy Dear Editor: The visual sensations experienced by patients during cataract surgery have been well documented.1–3 Here we report the visual sensations described by patients during vitrectomy under retrobulbar anesthesia. Twenty-eight men and 28 women with a mean age of 61.4⫾12.5 years and a variety of vitreoretinal pathologies (Table 1 [available at http://aaojournal.org]) were studied. The patients were questioned about their visual sensations during and within 3 hours after vitrectomy (Table 2 [available at http://aaojournal. org]). Fifty-four (96.4%) of the patients reported seeing lights, 46 (82.1%) reported seeing ⱖ1 colors, and 37 (66.1%) reported seeing movements or moving objects. Of the latter 37, 34 saw instruments, and 6 (13.0%) saw the surgeon’s fingers or hands. In the 51 cases of triamcinoloneassisted vitrectomy, 24 (47.1%) reported seeing many diffuse whirling black spots. Four patients (7.1%) found the
Author reply Dear Editor: Dr Venkatesh makes a valid observation that the uncorrected visual acuity results for manual small-incision cataract surgery (SICS) differ for the trial comparing it with conventional extracapsular cataract extraction (ECCE) in 20011 and that comparing it with phacoemulsification in 2003.2 The former had patients recruited from both the base hospital and the peripheral camps, whereas the latter had only outpatients from the base hospital. But the refraction in the peripheral camps was determined by trained ophthalmic assistants or optometrists in primary health centers with a refraction room. The difference in the results of the 2 trials also may have been due to surgeon learning curves. The 4 surgeons participating in the phacoemusification versus manual SICS trial were more experienced in 2003 than they were in 2001 for the same technique when it was being compared with conventional ECCE. I believe that manual SICS is very dependent on surgeon skill for its excellent result, and though it is easier for an ECCE trained surgeon, the learning curve is nonetheless significant. I appreciate Dr Venkatesh’s interest in this topic. His institution, the Aravind Eye Hospital, perhaps does more manual SICS surgery than any other in the world. PARIKSHIT GOGATE Pune, India References 1. Gogate PM, Deshpande M, Wormald RP, et al. Extracapsular cataract surgery compared with manual small incision cataract surgery in a community eye care setting in western India: a randomized control trial. Br J Ophthalmol 2003;87:667–72. 2. Gogate PM, Kulkarni SR, Krishnaiah S, et al. Safety and efficacy of phacoemulcification compared with manual small incision cataract surgery by a randomized control trial. Ophthalmology 2005;112:869 –74.
Intraoperative Floppy Iris Syndrome Dear Editor: Schwinn and Afshari have provided an interesting insight into the understanding of intraoperative floppy iris syndrome (IFIS).1 We share our experience concerning IFIS associated with doxazosin use. The authors propose that, in cases of IFIS associated with the other ␣1-adrenoceptor receptor antagonists, ophthalmologists might either monitor drug levels preoperatively or stop all these medications before cataract surgery. Our patient with IFIS associated with systemic doxazosin may represent a less severe form of the syndrome. We carried out right phacoemulsification surgery on a 70-year-old man. At the start of surgery, the pupil was well dilated at 7 mm. During the capsulorrhexis stage, the iris edges continually fluttered and became increasingly mobile with gradual pupillary miosis. Sodium hyaluronate 2.3% (Healon5, Advanced Medical Optics, Inc., Santa Ana, CA) was used effectively to stabilize the iris. The iris edges were mobile during cataract removal; however, sodium hyaluronate 2.3% was effective in maintaining a pupil size of around 5 mm. A high-vacuum phaco-chop technique (duallinear mode) was used to remove the cataractous lens within the capsular bag. This strategy allowed sodium hyaluronate 2.3% to remain in the anterior chamber and stabilize any iris movements anteriorly due to fluid currents in the posterior chamber. This method reduced the IFIS to mild iris rippling around the pupillary ruff, and we did not encounter any later problems with progressive miosis. Eleven months previously, the fellow eye had cataract surgery at a different center, and this was complicated by intraoperative miosis and IFIS. Technical problems were encountered associated with a floppy iris. Iris retractors were used mechanically to stretch the pupil; however, this was inadequate. A pars plana vitrectomy approach was required later to remove cortical matter trapped behind the lens implant optic. After a medical consultation postoperatively, the patient was reported to have been taking oral doxazosin 4 mg once daily for the treatment of hypertension over a 3-year period. In retrospect, the surgical findings of the case were consistent with a diagnosis of IFIS2 associated with chronic doxazosin use. Doxazosin is a nonselective ␣1-adrenoceptor receptor blocker and may have selective ␣1A-adrenoceptor receptor activity.3 This drug appears to induce iris muscle relaxation, similar to tamsulosin, but may result in a less severe form of IFIS. The dose of doxazosin is adjusted based on the blood pressure (BP) response and side effect profile of the individual. We observed a mild form of IFIS with a patient taking 4 mg over a long period. To determine a plasma level that does not cause IFIS, a large prospective clinical study would be needed. At present, a plasma level of doxazosin that would not increase the risk of IFIS is not known. However, the rate of IFIS may vary tremendously across patients who have the same drug level. On a more practical level, if ophthalmologists choose to withdraw the drug (doxazosin or tamsulosin), the elimination period for the drug may be monitored by
1885
Ophthalmology Volume 113, Number 10, October 2006 observing the BP and/or for the recurrence of urinary symptoms. No agreed-to preoperative recommendations currently exist for patients on doxazosin therapy for hypertension undergoing cataract surgery. There is a theoretical risk of rebound hypertension after sudden cessation of therapy, but so far we are not aware of reports in the literature.4 ␣1adrenoceptor receptor antagonists, such as tamsulosin and doxazosin, reduce the risk of acute urinary retention by half, to ⬍5%. Withdrawal of tamsulosin in patients with mild or moderate benign prostatic hyperplasia symptoms is unlikely to be complicated by acute urinary retention.5 Acute urinary retention may recur after tamsulosin withdrawal in patients with severe benign prostatic hyperplasia. Patients with severe benign prostatic hyperplasia and high risk of acute urinary retention are not generally on long-term ␣1-adrenoceptor receptor medical therapy. The manufacturer suggests safely stopping tamsulosin therapy 2 weeks before cataract surgery (personal communication, 2006). Patients may continue doxazosin treatment before cataract surgery; however, ophthalmologists must anticipate IFIS. Our experience of using sodium hyaluronate 2.3% and a high-vacuum phaco-chop technique allowed safe surgery to be performed in this case. The risks of rebound hypertension and acute retention may not be a significant management problem around the time of cataract surgery.4,5 However, any alterations to ␣-blocker regimens should be made in discussion with our urology, cardiology, and general practice colleagues. We agree with the current advice for ophthalmologists1,2— namely, that a careful medical and drug history be taken by the clinician and nursing staff during the preoperative assessment for cataract surgery. A risk profile for male and female patients taking ␣1-adrenoceptor receptor antagonists for hypertension and/or urinary tract disorders may need to be discussed with the patient before consent for cataract surgery is obtained. MAHIUL M. K. MUQIT MITCH J. MENAGE Leeds, United Kingdom References 1. Schwinn DA, Afshari NA. ␣1-adrenergic antagonists and floppy iris syndrome: tip of the iceberg? Ophthalmology 2005; 112:2059 – 60. 2. Chang DF, Campbell JR. Intraoperative floppy iris syndrome associated with tamsulosin. J Cataract Refract Surg 2005;31: 664 –73. 3. Yono M, Foster HE Jr, Shin D, et al. Doxazosin-induced up-regulation of alpha 1A-adrenoceptor mRNA in the rat lower urinary tract. Can J Physiol Pharmacol 2004;82:872– 8. 4. Takata Y, Yoshizumi T, Ito Y, et al. Effect of administration and withdrawal of doxazosin on ambulatory blood pressure in patients with essential hypertension. Angiology 1995;46:11– 8. 5. Barkin J, Guimaraes M, Jacobi G, et al. Alpha-blocker therapy can be withdrawn in the majority of men following initial combination therapy with the dual 5alpha-reductase inhibitor dutasteride. Eur Urol 2003;44:461– 6.
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Author reply Dear Editor: Drs Muqit and Menage suggest that intraoperative floppy iris syndrome may present as a spectrum of disease, from mild (as in their patient) to more clinically significant. Further, they document that intraoperative floppy iris syndrome can result from a spectrum of ␣1-adrenergic receptor antagonist drugs because their patient was taking doxazosin before surgery, whereas original reports centered around tamsulosin. They agree that there should be heightened awareness during preoperative physical examinations to the use of ␣1-adrenergic receptor antagonist drugs. It is important to note that a recently published study provides useful data with regard to ␣1-adrenergic receptor antagonists and iris biology.1 The study demonstrates that all commercially available ␣1-adrenergic receptor blockers (alfuzosin, doxazosin, naftopidil, tamsulosin, and terazosin) induce miosis in clinically relevant concentrations (defined by specific urologic effects), and that these effects are fully reversed within 8 hours of IV administration. This suggests that iris effects due to ␣1-adrenergic receptor antagonists would be minimized if such drugs were discontinued 2 to 3 days before surgery or, more conservatively, 1 to 2 weeks, given that the study was performed in albino rabbits and pigment effects remain unknown. As noted in our article, it should be remembered that intraoperative floppy iris syndrome may occur with other drugs and clinical disease entities, so the possible symptoms of floppy iris may remain in this elderly population even after ␣1-adrenergic receptor antagonists are eliminated as the cause. DEBRA A. SCHWINN, MD NATALIE A. AFSHARI, MD Durham, North Carolina Reference 1. Michel MC, Okutsu H, Noguchi Y, et al. In vivo studies on the effects of alpha1-adrenoceptor antagonists on pupil diameter and urethral tone in rabbits. Naunyn Schmiedebergs Arch Pharmacol 2006;372:346 –53.
Visual Sensations during Vitrectomy Dear Editor: The visual sensations experienced by patients during cataract surgery have been well documented.1–3 Here we report the visual sensations described by patients during vitrectomy under retrobulbar anesthesia. Twenty-eight men and 28 women with a mean age of 61.4⫾12.5 years and a variety of vitreoretinal pathologies (Table 1 [available at http://aaojournal.org]) were studied. The patients were questioned about their visual sensations during and within 3 hours after vitrectomy (Table 2 [available at http://aaojournal. org]). Fifty-four (96.4%) of the patients reported seeing lights, 46 (82.1%) reported seeing ⱖ1 colors, and 37 (66.1%) reported seeing movements or moving objects. Of the latter 37, 34 saw instruments, and 6 (13.0%) saw the surgeon’s fingers or hands. In the 51 cases of triamcinoloneassisted vitrectomy, 24 (47.1%) reported seeing many diffuse whirling black spots. Four patients (7.1%) found the