- Email: [email protected]
Eye Shield for Patients Undergoing Laser Treatment
Eye Shield for Patients Undergoing Laser Treatment Christine C. Nelson, M.D., Krystyna A. Pasyk, M.D., and Gregory 1. Dootz
We developed a patient eye shield consisting of a sandwich of polymethylmethacrylate and tinfoil to provide corneal and retinal protection from inadvertent injury during argon, neodymium:YAG, or dye laser treatment. The shield was tested with argon, dye, neodymium:YAG, and CO 2 lasers. This new eye shield is safe, comfortable, and easy to clean and use. LASER TREATMENT of vascular and nonvascular skin lesions on and around the eyelids is considered the domain of several specialties, including ophthalmology, dermatology, plastic surgery, otolaryngology, and oncology. Surgeons wear protective eye goggles during laser treatments, and the patient may wear similar goggles if the area of treatment is distant from the ocular adnexa. Eye shields, however, are needed during laser treatment of eyelids and periorbital lesionsY The risk of inadvertent injury to the patient's eye as well as to the eyes of the surgeon and the operating room personnel is significant if proper protective measures are not taken. The lens of the eye may focus the laser light dangerously by concentrating the energy directly on the retina, thus causing thermal or photochemical damage or both. Because there is typically no pain or discomfort associated with retinal laser burns, the damage that the burns cause will only be found during an ophthalmic examination in which the patient's pupils are dilated. Eye shields commonly used in eyelid and orbital surgery have been inappropriately used during treatment with lasers. Such use is dangerous because protective plastic devices used
Accepted for publication April 17, 1990. From the Departments of Ophthalmology (Dr. Nelson and Mr. Dootz) and Surgery, Section of Plastic and Reconstructive Surgery (Dr. Pasyk), University of Michigan Medical Center, Ann Arbor, Michigan. The authors have filed a patent application for the laser eye shield. Reprint requests to Christine C. Nelson, M.D., Kellogg Eye Center, 1000 Wall si.. Ann Arbor, MI 48105.
©AMERICAN JOURNAL OF OPHTHALMOLOGY
110:39-43,
JULY,
for eyelid surgery either absorb or transmit laser light, thereby generating heat or allowing retinal damage.v' The metallic devices are thick and heavy, which causes discomfort and distortion of the eyelids. Additionally, because of the devices' highly polished surfaces, specular reflection can occur. Therefore, a new prototype is necessary to protect the eyes of the patients and operating room personnel. Patient comfort and physician acceptance are as important to eye protection as is proper wavelength filtration. We developed a patient laser eye shield that decreases the risk of specular reflection and is safe, easy to use, and comfortable for the patient.
Material and Methods The eye shield is made of alternating layers of clear polymethylmethacrylate and tinfoil. The prototype consists of the following layers: 0.5 mm of polymethylmethacrylate, two 0.02-mm layers of tinfoil, 1 mm of polymethylmethacrylate, another layer of 0.02 mm of tinfoil, and a 0.5-mm posterior coating of polymethylmethacrylate (Fig. 1). The anterior surface of polymethylmethacrylate varies in thickness in the area of the l-cm handle. The eye shield measures 2.8 x 2.5 em and weighs 3.0 g. The eye shield should be sterilized before surgical use. The laser shield must be sterilized with gas or soaked in 10% formaldehyde solution for 20 minutes and thoroughly rinsed with sterile water. Alcohol must not be used on the laser shield because it will damage the polymethylmethacrylate coating. Before inserting the shield, a small amount of lubricating ophthalmic ointment is applied to the posterior concave surface of the sterile eye shield. Before insertion of the eye shield, the patient's eyes should be anesthetized with one to two drops of topical ophthalmic anesthetic solution. Eye shields should be placed in both eyes to ensure adequate protection to the eye not undergoing laser treatment. Placement of 1990
39
40
July, 1990
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 1 (Nelson, Pasyk, and Dootz). Patient laser eye shield. Top left, Anterior convex surface. Top right, Posterior concave surface. Bottom left, Note small polymethylmethacrylate handle. Bottom right, Side view of eye shield.
the eye shield may be accomplished with either forceps or fingers. The polymethylmethacrylate handle allows easy insertion and removal of the shield (Fig. 2). The eye may be rinsed after removal of the shield if any ointment remains. The prototype eye shield was tested for its effectiveness and limitations by the Chemistry and Materials Science Laser Spectroscopy Laboratory at our institution. In this laboratory, two kinds of lasers were used: the argon laser (488 to 514 nm) Coherent CR 18 model (Coherent Medical Company, Palo Alto, California), and neodymium:YAG laser (1,064 nm) Quantronix 416 model (Quantronix Corporation, Smithtown, New York). The laser beam was directed perpendicular (normal) to the plane formed by the posterior outer circular edge of the shield. The power of the argon laser was increased from 0.5 to 3.5 W with a beam diameter of 2 mm in continuous-wave mode. The exposure time varied from ten seconds to ten minutes. The power of the Nd:YAG laser was gradually increased from 1 to 9 W with a beam diameter of 1 mm in continuous-wave mode. The exposure time varied from three seconds to five minutes. Before clinical studies, the prototype eye shield was tested with three clinical lasers: the argon laser (Meditec DL 5000 dermatologic
model, Aesculap, Burlingame, California); the tunable dye laser (Meditec MDS-I0 type, Aesculap); and the CO 2 laser Coherent Medical Group Xanar (Coherent Medical Company, Palo Alto, California). The argon laser power was varied from 2 to 4 W by using a I-mm spot size in continuous-wave mode from one second to one minute. The dye laser was tested at three wavelengths (577, 600, and 630 nm) from one to ten seconds while the power remained at 1 W in continuous-wave mode with a I-mm spot size. The CO 2 laser was tested from one second to one minute of exposure time with powers varying from 0.5 to 10 W using the unfocused mode. In the focused mode, the CO 2 was tested with O.I-mm and O.2-mm spot size from one to five seconds of exposure time. After each laser testing, the eye shield was examined for thermal damage, perforation, and any increase in temperature to palpation on the posterior surface.
Results
With the Coherent CR 18 argon laser, there was no effect on the eye shield with a 2-mm beam in continuous mode with 1 W of power for
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Laser Eye Shield
41
With the CO 2 laser Coherent Medical Group Xanar, there was no effect on the eye shield with 0.5 W of power unfocused for one minute. As the power of the unfocused beam was increased to 4 W, the anterior polymethylmethacrylate surface became warm and eventually melted. No perforation of the shield, however, was noted after one minute of exposure time. Using a focused O.2-mm beam of the CO 2 laser for five seconds at 2 to 5 W, the anterior surface became warm and gradually melted. However, there was still no perforation. The shield was perforated after one second with 10 W of power with the CO 2 laser.
Discussion
Fig. 2 (Nelson, Pasyk, and Dootz). Laser eye shield on patient with no interference of eyelid position.
one minute. There was a slightly warm area on the anterior surface of the shield but no residual dimple or burn with an increase in the power to 2 W for five minutes. Similarly, the anterior surface warmed slightly but there was no damage after 15 seconds of exposure to the argon laser at 3 W. With the Quantronix 416 model Nd:YAG laser, no effect on the eye shield was noted with a I-mm beam diameter in continuous-wave mode at 1 W of power for five minutes. Increasing the power to 3 W for 30 seconds caused the anterior surface to become warm. A small white outward protrusion formed on the anterior surface of the eye shield after a five-second exposure of the Nd:YAG laser beam at 5 W of power. This shield was perforated with 9 W of power after ten seconds of exposure to the L-mm beam size in continuous-wave mode. With the clinical Meditec DL 5000 dermatologle model argon laser, no reaction on the eye shield was observed after a IS-second exposure to 3 W of power with a 2-mm spot size in continuous-wave mode. The shield was perforated after 30 seconds using a I-mm spot size at a power of 4 W in continuous-wave mode. With the Meditec MDS-I0 type Dye Laser, the eye shield was not affected by a power of 1 W with a I-mm spot size in continuous-wave mode for 10 seconds at 577 nm, 600 nm, or 630 nm.
With increased use of lasers by a variety of specialists, there have been more reports of injuries, making safety standards important.t" The Laser Institute of America provides guidance for the safe use of lasers and laser systems.":" Detailed guidelines and improved goggles were developed to protect the eyes of those who work with lasers. The goggles are used to avoid damage from stray, reflected light and sometimes even direct laser light. For increased protection, both surgeon and patient wear similar safety goggles during laser therapy if the area of treatment is distant from the eyelids. Little has been written, however, about protecting the patient when the standard safety goggles are inappropriate, for example, when they are too large for a child or if the eyelid and orbital areas are to be treated. No matter how effective the protective eyewear, it will be practically useless if it is so uncomfortable for the patient, or so difficult for the surgeon to use, that it is used reluctantly or not at all. The Smith Evaginated Corneal Protection Shield (Mager and Gougelman, New York, New York) was originally developed to protect the patient's eye from the surgeon's scalpel. These shields have been used during periorbital laser surgery." The green color of this shield absorbs the laser light. The absorbed laser energy is subsequently converted to heat and may cause damage to the polymethylmethacrylate and consequently the eye itself. The Hornblass Ocular Protection Shield (Mager and Gougelman, New York, New York), also made of polymethylmethacrylate, has also been reported for use with lasers. 1,4 The intended use of this shield was to protect the eye from
42
July, 1990
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 3 (Nelson, Pasyk, and Dootz). Stefanovsky device sinks into inferior fornix because of the device's weight. Handle interferes with laser treatment of lower eyelid (arrow).
the scalpel during surgery; it was never intended to shield the patient from the laser. Furthermore, because they are produced in a variety of colors, the Hornblass shield absorbs laser energy in the same detrimental manner as does the Smith Shield. The Stefanovsky Laser Protective Eye Shield (Stefanovsky and Associates, Willowick, Ohio), however, was developed specifically for use with the laser. It is made of high-grade, highly polished stainless steel, which makes it virtually impenetrable to the laser beam. Unfortunately, it also has disadvantages. This eye shield subjects operating room personnel to the risk of specular reflection during laser use. The risk is so high that the Stefanovsky shield comes with this warning. Additionally, because it is heavy and thick, it is uncomfortable for the patient. Further, the knurled ball-grip feature, although it allows effortless placement and removal, extends 1.3 by 0.6 em, and therefore often interferes with laser surgery directed at the eyelid margin or pretarsal eyelid area. Moreover, because this eye shield is heavy (weight, 9.9 g), it sinks slowly into the inferior fornix during laser treatment (Fig. 3). This disadvantage requires the surgeon to hold the grip throughout the laser treatment to allow proper protection of the globe and to allow the lower eyelid to be treated. The manufacturer does not recommend this shield for use with the Nd:YAG laser. The new patient laser eye shield has been developed to protect the patients' eyes during
treatments to the ocular adnexa. All physicians currently using the argon, dye, or Nd:YAG lasers as well as the CO 2 laser at low power would be able to use the shield to protect their patients' eyes. Our new patient eye shield is sturdy and resistant to heat buildup and specular reflection. The clear polymethylmethacrylate allows the laser light to be diffusely reflected off the dull tinfoil layer rather than be absorbed. There is, therefore, no heat damage to the polymethylmethacrylate and no harmful specular reflection. The new eye shield has been tested to withstand the direct argon laser light in continuouswave mode with a I-mm spot size for 15 seconds of exposure at a power of 4 W. Typically, the power of the argon laser used in the treatment of the eyelid area is between 1.0 and 1.7 W, so the shield would be safe for clinical needs. It has been found to be safe with the Nd:YAG laser in continuous-wave mode using a I-mm spot size at a power of 2 W for five minutes of exposure. It can also be safely used with the dye laser (577 nm, 600 nrn, and 630 nm) at a power of 1 Wand a I-mm spot size in continuous-wave mode. At these settings, the shield would protect the globe from any heat or light energy injury. The eye shield is also effective in protecting the globe from the CO 2 laser at low power (0.5 W) in focused and unfocused modes and at higher powers up to 5 W in focused and unfocused modes for brief (five seconds or less) exposure times. Moreover, this laser eye shield may be used safely in the operating room to protect the globe from scalpel injury during routine eyelid surgery. Any physician using an argon, dye, Nd:YAG laser, or CO 2 laser on the face, especially around the eyes, wants safety and comfort for the patient as well as ease and flexibility during the treatment. The new laser shield is safer, more comfortable, and more flexible than any being currently used.
References 1. Goldman, L.: Laser skin surgery. In Epstein, E., and Epstein, E., Jr. (eds.): Skin Surgery. Springfield, Charles C Thomas, 1982, pp. 1143-1160. 2. Rockwell, R. M., [r.: Safety procedures for Nd:YAG laser surgery. In Joffe, S. N., and Oguro, Y. (eds.): Advances in Nd:YAG Laser Surgery. New York, Springer-Verlag, 1988, pp. 311-329.
Vol. 110, No.1
Laser Eye Shield
3. Summers, C. G., Hordinsky, M. D.: Argon laser treatment of periocular lesions. An experimental study. Ophthalmic Surg. 18:100, 1987. 4. Wheeland, R. G., Balin, P. L., Ratz, J. L., and Schreffler, D. E.: Use of scleral eye shields for periorbital laser surgery. J. Dermatol. Surg. Oncol. 13:156,1987. 5. Rathey, A. S.: Accidental laser burn of the macula. Arch. Ophthalmol. 74:346, 1965. 6. Asano, T.: Accidental YAG laser burn. Am. J. Ophthalmol. 98:116,1984.
43
7. Wolfe, J. A.: Laser accidents (Letter to the Editor). Arch. Ophthalmol. 103:174, 1985. 8. Rodriguez, J. G., and Sartin, R. W.: Injuries as an adverse reaction to clinically used laser devices. Lasers Surg. Med. 7:457, 1987. 9. Mittelman, H., and Apfelberg, D. B.: Carbon dioxide laser blepharoplasty. Advantages and disadvantages. Ann. Plast. Surg. 24:1, 1990. 10. Laser Institute of America: Safe Use of Lasers. Toledo, 1986, ANSI Z 136.1. 11. - - : Laser Safety Guide, ed. 6. Toledo, 1986.
OPHTHALMIC MINIATURE
SO through the eyes love attains the heart: For the eyes are the scouts of the heart, And the eyes go reconnoitering For what it would please the heart to possess. Guiraut de Borneilh (1138-1200?) Joseph Campbell (ed.), The Power of Myth New York, Doubleday, 1988, p. 186
We developed a patient eye shield consisting of a sandwich of polymethylmethacrylate and tinfoil to provide corneal and retinal protection from inadvertent injury during argon, neodymium:YAG, or dye laser treatment. The shield was tested with argon, dye, neodymium:YAG, and CO 2 lasers. This new eye shield is safe, comfortable, and easy to clean and use. LASER TREATMENT of vascular and nonvascular skin lesions on and around the eyelids is considered the domain of several specialties, including ophthalmology, dermatology, plastic surgery, otolaryngology, and oncology. Surgeons wear protective eye goggles during laser treatments, and the patient may wear similar goggles if the area of treatment is distant from the ocular adnexa. Eye shields, however, are needed during laser treatment of eyelids and periorbital lesionsY The risk of inadvertent injury to the patient's eye as well as to the eyes of the surgeon and the operating room personnel is significant if proper protective measures are not taken. The lens of the eye may focus the laser light dangerously by concentrating the energy directly on the retina, thus causing thermal or photochemical damage or both. Because there is typically no pain or discomfort associated with retinal laser burns, the damage that the burns cause will only be found during an ophthalmic examination in which the patient's pupils are dilated. Eye shields commonly used in eyelid and orbital surgery have been inappropriately used during treatment with lasers. Such use is dangerous because protective plastic devices used
Accepted for publication April 17, 1990. From the Departments of Ophthalmology (Dr. Nelson and Mr. Dootz) and Surgery, Section of Plastic and Reconstructive Surgery (Dr. Pasyk), University of Michigan Medical Center, Ann Arbor, Michigan. The authors have filed a patent application for the laser eye shield. Reprint requests to Christine C. Nelson, M.D., Kellogg Eye Center, 1000 Wall si.. Ann Arbor, MI 48105.
©AMERICAN JOURNAL OF OPHTHALMOLOGY
110:39-43,
JULY,
for eyelid surgery either absorb or transmit laser light, thereby generating heat or allowing retinal damage.v' The metallic devices are thick and heavy, which causes discomfort and distortion of the eyelids. Additionally, because of the devices' highly polished surfaces, specular reflection can occur. Therefore, a new prototype is necessary to protect the eyes of the patients and operating room personnel. Patient comfort and physician acceptance are as important to eye protection as is proper wavelength filtration. We developed a patient laser eye shield that decreases the risk of specular reflection and is safe, easy to use, and comfortable for the patient.
Material and Methods The eye shield is made of alternating layers of clear polymethylmethacrylate and tinfoil. The prototype consists of the following layers: 0.5 mm of polymethylmethacrylate, two 0.02-mm layers of tinfoil, 1 mm of polymethylmethacrylate, another layer of 0.02 mm of tinfoil, and a 0.5-mm posterior coating of polymethylmethacrylate (Fig. 1). The anterior surface of polymethylmethacrylate varies in thickness in the area of the l-cm handle. The eye shield measures 2.8 x 2.5 em and weighs 3.0 g. The eye shield should be sterilized before surgical use. The laser shield must be sterilized with gas or soaked in 10% formaldehyde solution for 20 minutes and thoroughly rinsed with sterile water. Alcohol must not be used on the laser shield because it will damage the polymethylmethacrylate coating. Before inserting the shield, a small amount of lubricating ophthalmic ointment is applied to the posterior concave surface of the sterile eye shield. Before insertion of the eye shield, the patient's eyes should be anesthetized with one to two drops of topical ophthalmic anesthetic solution. Eye shields should be placed in both eyes to ensure adequate protection to the eye not undergoing laser treatment. Placement of 1990
39
40
July, 1990
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 1 (Nelson, Pasyk, and Dootz). Patient laser eye shield. Top left, Anterior convex surface. Top right, Posterior concave surface. Bottom left, Note small polymethylmethacrylate handle. Bottom right, Side view of eye shield.
the eye shield may be accomplished with either forceps or fingers. The polymethylmethacrylate handle allows easy insertion and removal of the shield (Fig. 2). The eye may be rinsed after removal of the shield if any ointment remains. The prototype eye shield was tested for its effectiveness and limitations by the Chemistry and Materials Science Laser Spectroscopy Laboratory at our institution. In this laboratory, two kinds of lasers were used: the argon laser (488 to 514 nm) Coherent CR 18 model (Coherent Medical Company, Palo Alto, California), and neodymium:YAG laser (1,064 nm) Quantronix 416 model (Quantronix Corporation, Smithtown, New York). The laser beam was directed perpendicular (normal) to the plane formed by the posterior outer circular edge of the shield. The power of the argon laser was increased from 0.5 to 3.5 W with a beam diameter of 2 mm in continuous-wave mode. The exposure time varied from ten seconds to ten minutes. The power of the Nd:YAG laser was gradually increased from 1 to 9 W with a beam diameter of 1 mm in continuous-wave mode. The exposure time varied from three seconds to five minutes. Before clinical studies, the prototype eye shield was tested with three clinical lasers: the argon laser (Meditec DL 5000 dermatologic
model, Aesculap, Burlingame, California); the tunable dye laser (Meditec MDS-I0 type, Aesculap); and the CO 2 laser Coherent Medical Group Xanar (Coherent Medical Company, Palo Alto, California). The argon laser power was varied from 2 to 4 W by using a I-mm spot size in continuous-wave mode from one second to one minute. The dye laser was tested at three wavelengths (577, 600, and 630 nm) from one to ten seconds while the power remained at 1 W in continuous-wave mode with a I-mm spot size. The CO 2 laser was tested from one second to one minute of exposure time with powers varying from 0.5 to 10 W using the unfocused mode. In the focused mode, the CO 2 was tested with O.I-mm and O.2-mm spot size from one to five seconds of exposure time. After each laser testing, the eye shield was examined for thermal damage, perforation, and any increase in temperature to palpation on the posterior surface.
Results
With the Coherent CR 18 argon laser, there was no effect on the eye shield with a 2-mm beam in continuous mode with 1 W of power for
Vol. 110, No.1
Laser Eye Shield
41
With the CO 2 laser Coherent Medical Group Xanar, there was no effect on the eye shield with 0.5 W of power unfocused for one minute. As the power of the unfocused beam was increased to 4 W, the anterior polymethylmethacrylate surface became warm and eventually melted. No perforation of the shield, however, was noted after one minute of exposure time. Using a focused O.2-mm beam of the CO 2 laser for five seconds at 2 to 5 W, the anterior surface became warm and gradually melted. However, there was still no perforation. The shield was perforated after one second with 10 W of power with the CO 2 laser.
Discussion
Fig. 2 (Nelson, Pasyk, and Dootz). Laser eye shield on patient with no interference of eyelid position.
one minute. There was a slightly warm area on the anterior surface of the shield but no residual dimple or burn with an increase in the power to 2 W for five minutes. Similarly, the anterior surface warmed slightly but there was no damage after 15 seconds of exposure to the argon laser at 3 W. With the Quantronix 416 model Nd:YAG laser, no effect on the eye shield was noted with a I-mm beam diameter in continuous-wave mode at 1 W of power for five minutes. Increasing the power to 3 W for 30 seconds caused the anterior surface to become warm. A small white outward protrusion formed on the anterior surface of the eye shield after a five-second exposure of the Nd:YAG laser beam at 5 W of power. This shield was perforated with 9 W of power after ten seconds of exposure to the L-mm beam size in continuous-wave mode. With the clinical Meditec DL 5000 dermatologle model argon laser, no reaction on the eye shield was observed after a IS-second exposure to 3 W of power with a 2-mm spot size in continuous-wave mode. The shield was perforated after 30 seconds using a I-mm spot size at a power of 4 W in continuous-wave mode. With the Meditec MDS-I0 type Dye Laser, the eye shield was not affected by a power of 1 W with a I-mm spot size in continuous-wave mode for 10 seconds at 577 nm, 600 nm, or 630 nm.
With increased use of lasers by a variety of specialists, there have been more reports of injuries, making safety standards important.t" The Laser Institute of America provides guidance for the safe use of lasers and laser systems.":" Detailed guidelines and improved goggles were developed to protect the eyes of those who work with lasers. The goggles are used to avoid damage from stray, reflected light and sometimes even direct laser light. For increased protection, both surgeon and patient wear similar safety goggles during laser therapy if the area of treatment is distant from the eyelids. Little has been written, however, about protecting the patient when the standard safety goggles are inappropriate, for example, when they are too large for a child or if the eyelid and orbital areas are to be treated. No matter how effective the protective eyewear, it will be practically useless if it is so uncomfortable for the patient, or so difficult for the surgeon to use, that it is used reluctantly or not at all. The Smith Evaginated Corneal Protection Shield (Mager and Gougelman, New York, New York) was originally developed to protect the patient's eye from the surgeon's scalpel. These shields have been used during periorbital laser surgery." The green color of this shield absorbs the laser light. The absorbed laser energy is subsequently converted to heat and may cause damage to the polymethylmethacrylate and consequently the eye itself. The Hornblass Ocular Protection Shield (Mager and Gougelman, New York, New York), also made of polymethylmethacrylate, has also been reported for use with lasers. 1,4 The intended use of this shield was to protect the eye from
42
July, 1990
AMERICAN JOURNAL OF OPHTHALMOLOGY
Fig. 3 (Nelson, Pasyk, and Dootz). Stefanovsky device sinks into inferior fornix because of the device's weight. Handle interferes with laser treatment of lower eyelid (arrow).
the scalpel during surgery; it was never intended to shield the patient from the laser. Furthermore, because they are produced in a variety of colors, the Hornblass shield absorbs laser energy in the same detrimental manner as does the Smith Shield. The Stefanovsky Laser Protective Eye Shield (Stefanovsky and Associates, Willowick, Ohio), however, was developed specifically for use with the laser. It is made of high-grade, highly polished stainless steel, which makes it virtually impenetrable to the laser beam. Unfortunately, it also has disadvantages. This eye shield subjects operating room personnel to the risk of specular reflection during laser use. The risk is so high that the Stefanovsky shield comes with this warning. Additionally, because it is heavy and thick, it is uncomfortable for the patient. Further, the knurled ball-grip feature, although it allows effortless placement and removal, extends 1.3 by 0.6 em, and therefore often interferes with laser surgery directed at the eyelid margin or pretarsal eyelid area. Moreover, because this eye shield is heavy (weight, 9.9 g), it sinks slowly into the inferior fornix during laser treatment (Fig. 3). This disadvantage requires the surgeon to hold the grip throughout the laser treatment to allow proper protection of the globe and to allow the lower eyelid to be treated. The manufacturer does not recommend this shield for use with the Nd:YAG laser. The new patient laser eye shield has been developed to protect the patients' eyes during
treatments to the ocular adnexa. All physicians currently using the argon, dye, or Nd:YAG lasers as well as the CO 2 laser at low power would be able to use the shield to protect their patients' eyes. Our new patient eye shield is sturdy and resistant to heat buildup and specular reflection. The clear polymethylmethacrylate allows the laser light to be diffusely reflected off the dull tinfoil layer rather than be absorbed. There is, therefore, no heat damage to the polymethylmethacrylate and no harmful specular reflection. The new eye shield has been tested to withstand the direct argon laser light in continuouswave mode with a I-mm spot size for 15 seconds of exposure at a power of 4 W. Typically, the power of the argon laser used in the treatment of the eyelid area is between 1.0 and 1.7 W, so the shield would be safe for clinical needs. It has been found to be safe with the Nd:YAG laser in continuous-wave mode using a I-mm spot size at a power of 2 W for five minutes of exposure. It can also be safely used with the dye laser (577 nm, 600 nrn, and 630 nm) at a power of 1 Wand a I-mm spot size in continuous-wave mode. At these settings, the shield would protect the globe from any heat or light energy injury. The eye shield is also effective in protecting the globe from the CO 2 laser at low power (0.5 W) in focused and unfocused modes and at higher powers up to 5 W in focused and unfocused modes for brief (five seconds or less) exposure times. Moreover, this laser eye shield may be used safely in the operating room to protect the globe from scalpel injury during routine eyelid surgery. Any physician using an argon, dye, Nd:YAG laser, or CO 2 laser on the face, especially around the eyes, wants safety and comfort for the patient as well as ease and flexibility during the treatment. The new laser shield is safer, more comfortable, and more flexible than any being currently used.
References 1. Goldman, L.: Laser skin surgery. In Epstein, E., and Epstein, E., Jr. (eds.): Skin Surgery. Springfield, Charles C Thomas, 1982, pp. 1143-1160. 2. Rockwell, R. M., [r.: Safety procedures for Nd:YAG laser surgery. In Joffe, S. N., and Oguro, Y. (eds.): Advances in Nd:YAG Laser Surgery. New York, Springer-Verlag, 1988, pp. 311-329.
Vol. 110, No.1
Laser Eye Shield
3. Summers, C. G., Hordinsky, M. D.: Argon laser treatment of periocular lesions. An experimental study. Ophthalmic Surg. 18:100, 1987. 4. Wheeland, R. G., Balin, P. L., Ratz, J. L., and Schreffler, D. E.: Use of scleral eye shields for periorbital laser surgery. J. Dermatol. Surg. Oncol. 13:156,1987. 5. Rathey, A. S.: Accidental laser burn of the macula. Arch. Ophthalmol. 74:346, 1965. 6. Asano, T.: Accidental YAG laser burn. Am. J. Ophthalmol. 98:116,1984.
43
7. Wolfe, J. A.: Laser accidents (Letter to the Editor). Arch. Ophthalmol. 103:174, 1985. 8. Rodriguez, J. G., and Sartin, R. W.: Injuries as an adverse reaction to clinically used laser devices. Lasers Surg. Med. 7:457, 1987. 9. Mittelman, H., and Apfelberg, D. B.: Carbon dioxide laser blepharoplasty. Advantages and disadvantages. Ann. Plast. Surg. 24:1, 1990. 10. Laser Institute of America: Safe Use of Lasers. Toledo, 1986, ANSI Z 136.1. 11. - - : Laser Safety Guide, ed. 6. Toledo, 1986.
OPHTHALMIC MINIATURE
SO through the eyes love attains the heart: For the eyes are the scouts of the heart, And the eyes go reconnoitering For what it would please the heart to possess. Guiraut de Borneilh (1138-1200?) Joseph Campbell (ed.), The Power of Myth New York, Doubleday, 1988, p. 186