- Email: [email protected]
Precarved Lyophilized Tissue for Lamellar Keratoplasty in Recurrent Pterygium
Precarved Lyophilized Tissue for Lamellar Keratoplasty in Recurrent Pterygium Massimo Busin, M.D., Brett L. Halliday, M.D., F.R.C.S., Robert C. Arffa, M.D., Marguerite B. McDonald, M.D., and Herbert E. Kaufman, M.D.
Thirteen eyes with recurrent pterygia were treated with excision and lamellar keratoplasty using precarved, lyophilized donor cornea. After an average follow-up of 23 months, only one eye (7.7%) required repeat excision. Two eyes (15.4%) had minor recurrences that were asymptomatic and did not progress. Minimal vascularization at the interface between donor and recipient cornea was frequent, but this completely regressed after suture removal and topical corticosteroid treatment. Limitation of movement, when present preoperatively, was improved or eliminated. Best corrected visual acuity was unchanged in eight eyes (61.5%), decreased by one line in two eyes (15.4%), and improved by one or two lines in three eyes (23.1 %). Postoperative astigmatism was within 0.5 diopter of the preoperative value in 11 eyes (84.6%); one eye (7.7%) had a postoperative increase of 1 diopter and another eye (7.7%) of 2 diopters. REPORTED RATES Of recurrence of a pterygium after primary excision vary from 0% to 69%.1-3 However, the most recent reports indicate a recurrence rate of 37% to 44%.4-6 The likelihood of recurrence is higher in young patients and in those with marked activity preoperatively. 5 The treatment of recurrent pterygia is a problem that has not been solved despite the variety of surgical techniques used. Most investigators
Accepted for publication June 4, 1986. From the Lions Eye Research Laboratories, LSU Eye Center, Louisiana State University Medical Center School of Medicine, New Orleans, Louisiana. This study was supported in part by Public Health Service grants EY02580, EY07073, and EY02377 from the National Eye Institute and by a traveling scholarship from the Royal College of Surgeons Foundation, Inc., New York City (Dr. Halliday). Reprint requests to Marguerite B. McDonald, M.D., LSU Eye Center, 136 S. Roman St., New Orleans, LA 70112.
222
have not distinguished between approaches to primary pterygia and recurrent pterygia. Recommended techniques have included dissecting the pterygium from the surface of the cornea and burying the head,":" excision leaving a bare scleral area,":" and a conjunctival graft. 10,15-19 Lamellar keratoplasty for the treatment of pterygia was first described in 1916 by Magitot." Despite reports of its successful use,4,21-24 it has not been employed extensively, partly because of the complexity of the technique. Precarved, lyophilized tissue, which offers the potential for a simplified surgical technique, has been produced here since 1981, and has been available commercially since 1984. We have used carved and lyophilized donor tissue in lamellar keratoplasty for recurrent pterygia in 13 eyes of ten patients.
Subjects and Methods We reviewed retrospectively the records of all patients treated here who underwent excision of recurrent pterygium followed by lamellar keratoplasty with precarved, lyophilized tissue. All such patients with six or more months of follow-up were included. A total of ten patients (13 eyes) with an average of 23 months follow-up (range, six to 44 months) were examined (Table). There were nine men and one woman. The average age was 43 years (range, 30 to 66 years). All the patients were residents of southern states; three had predominantly outdoor occupations. All ten had had previous surgery, with an average of 2.2 pterygium removals from the affected eye. Two eyes (15.4%) had received mucous membrane grafts and eight (61.5%) had been treated with beta irradiation. Preoperative examination included determi-
©AMERICAN JOURNAL OF OPHTHALMOLOGY
102:222-227,
AUGUST,
1986
Vol. 102, No. 2
Lyophilized Tissue for Pterygium
223
Fig. 1 (Busin and associates). Schematic representation of lamellar keratoplasty for pterygium. The pterygium (top left) is dissected from the underlying corneal and conjunctival tissue (top right) and removed in toto. A partial-thickness, vertical incision is made at the central edge of the affected cornea, and a lamellar dissection (middle left) is performed, incorporating the entire area covered by the pterygium. The donor tissue is cut to the proper size and sutured into the corneal bed with 10-0 nylon interrupted sutures (middle right). Normal conjunctiva is used to cover the adjacent bare sclera (bottom left).
224
August, 1986
AMERICAN JOURNAL OF OPHTHALMOLOGY
TABLE SUMMARY OF CLINICAL DATA FOR TEN PATIENTS (13 EYES) WITH RECURRENT PTERYGIUM PREVIOUS TREATMENT PATIENT NO., SEX, AGE (VRS)
1, 2, 3, 4, 5,
M, 33 M, 44 F,50 M, 53 M, 25
6, M, 34 7, M, 44 8, M, 55 9, M, 52 10, M, 41
AFFECTED
MUCOUS MEMBRANE
SURGERY
VISUAL ACUITY
BETA IRRADIATION
GRAFT
(NO.)
PREOPERATIVE
POSTOPERATIVE
Left
No
Yes
Left
No
No
2 1
20/20 20/20
Left
Yes
No
Left
Yes
Yes
Right
Yes
No No
3 4 1 1
20/25 20/20 20/20 20/20 20/30
20/20 20/20 20/25
EYE
Left
Yes
Right
No
No
Right
Yes
No
Right
Yes
No
Left
Yes
No
Left
No
No
Right
No
No
3 3 2 2 2 2
Left
Yes
No
2
20/20 20/20 20/20 20/30 20/25 20/20
20/25 20/20 20/20 20/20 20/20 20/15 20/15 20/30 20/30 20/20
"Maximum extension into the cornea from the corneosclerallimbus. 'Vessels regressed completely after suture removal and topical corticosteroid therapy. INo symptomatic recurrence. Patient 1 had a fibrovascular ingrowth at the lower edge of the graft, extending about 1 mm into the cornea. Patient 6 had fibrovascular ingrowths superiorly and inferiorly. The ingrowths are stable in both cases. §After a recurrence the patient was treated elsewhere with excision and mucous membrane graft. Refraction was done after this second operation.
nation of visual acuity and refractive error, assessment of motility, and measurement, with drawings and photographs, of the pterygium. Surgery was performed under general (seven eyes; 53.8%) or local (six eyes; 46.2%) anesthesia. The pterygium was dissected from the cornea (Fig. 1, top left and top right) and a lamellar keratectomy was performed incorporating the entire area covered by pterygium (Fig. 1, middle left). This was accomplished first by the creation of a partial-thickness vertical incision in clear cornea, beginning just central to the head of the pterygium bed and extending above and below to the corneoscleral limbus. The conjunctival body of the pterygium was removed together with underlying scar tissue, freeing the adjacent rectus muscle if it appeared to be involved. In some cases a subconjunctival injection of local anesthetic was used to "balloon" the conjunctiva and make the dissection easier. Hemostasis was obtained with bipolar cautery. The precarved, lyophilized lenticule of corneal stroma has an intact Bowman's layer. It is shaped on a cryolathe from the endothelial surface to a uniform thickness of 0.3 mm, and
trephined to a diameter of 10.0 mm. The lens is rehydrated in a balanced salt solution containing gentamicin, 100 ug/rnl, for 20 minutes before use. Commercially prepared tissue was used in six eyes (46.2%) and locally prepared tissue in seven eyes (53.8%). At surgery, the tissue was cut to the proper size and sutured into the prepared corneal bed with 10-0 nylon interrupted sutures (Fig. 1, middle right). Normal conjunctiva was used to cover the bare sclera and restore limbal anatomy (Fig. 1, bottom left). If possible, a pedunculated flap was created from adjacent normal conjunctiva (ten eyes; 76.9%); otherwise, a free autograft was used (three eyes; 23.1%). The conjunctiva was sutured with 7-0 chromic catgut. Subconjunctival20-mg injections of gentamicin sulfate and 40-mg injections of methylprednisolone acetate were administered at the end of surgery, well away from the operative area. In six eyes (46.2%), a bandage contact lens was applied before the eye was patched and shielded. Postoperative antibiotic, mydriatic, and corticosteroid drugs were given as necessary. The bandage contact lens, when present, was re-
Vol. 102, No. 2
Lyophilized Tissue for Pterygium
225
TABLE (Continued)
REFRACTION PREOPERATIVE
0.00 +0.25 -1.00 + 2.00 -1.75 -2.25 +0.50 -2.25 -0.50 -0.50 -1.25 +1.75 -0.75
+ + + + + + + +
0.50 1.00 2.50 1.00 0.50 0.75 1.50 0.25
x x x x x x x x
25 60 105 115 90 90 180 10
+ 1.00 x 65 + 0.25 x 125 + 0.50 x 110
SIZE OF POSTOPERATIVE
0.00 +0.50 -1.50 +0.50
+ + + +
0.50 0.50 3.00 0.50
x x x x
PTERYGIUM
FOLLOW-UP
INTERFACE
(MM)'
(MOB)
VESSELS
3.0 5.0 6.0 3.5 4.0 4.0 4.0 3.0 3.0 2.0 3.0 3.5 2.0
6 15 15 6 44 44 6 9 34 34 38 38 6
Yes'
90 90 90§ 105
Unchanged Unchanged
-1.00 -2.25 -1.75 -1.75 0.00 -2.25 -1.75
+ 1.75 x 70 + 0.50 x 10
+ 0.75 x 75 + 1.25 x 110 + 2.50 x 90
moved when epithelial healing was complete, approximately four days after surgery.
Results There were no operative complications. Postoperative recovery was uneventful in all but one eye, with rapid graft and conjunctival flap healing. Corneal sutures were removed when healing appeared satisfactory. In general, one half of the 10-0 sutures were removed two weeks after surgery and the remainder after four weeks (Figs. 2 to 4). Vascularization in the plane between the donor and the host cornea occurred in nine of the 13 eyes (69.2%). The vessels did not extend into the cornea for more than 1 mm, and in all cases regression occurred after removal of the 10-0 sutures and treatment with topical corticosteroids. Postoperative complications requiring further surgery occurred in only one eye (7.7%) (Patient 3). In this patient the central edge of the lamellar graft folded under itself, and it was necessary to trim the edge and resuture the graft. Subsequently, a temporary tarsorrhaphy was required for epithelial healing. Three months later a symptomatic recurrence of the pterygium occurred, which was excised elsewhere with placement of a mucous membrane graft.
RECURRENCE
Yes'
NOl No
Yes'
Yes
Yes'
No No
Yes' Yes' Yes'
No
Yes' Yest
No
No No No NOl No No No No No No
Asymptomatic pterygium recurrence, requiring no further surgery, occurred in two additional eyes (15.4%). In Patient 1, a recurrence developed at the lower edge of the corneal lamellar graft, extending for about 1 mm into the cornea. It was treated with an argon laser and regressed over the next four months; it is currently stable. In Patient 6, fibrovascular tissue grew over the upper and lower edges of the lamellar graft approximately 2 mm into the cornea but progressed no farther. The preoperative limitation of movement from medial rectus muscle involvement, present preoperatively in four eyes (30.8%), was
Fig. 2 (Busin and associates). Case 1, two days after surgery.
226
AMERICAN JOURNAL OF OPHTHALMOLOGY
August, 1986
Fig. 3 (Busin and associates). Case 4, seven weeks after surgery. The sutures were removed one week previously.
Fig. 4 (Busin and associates). Case 7, eight months after surgery. The donor lamellar graft is clear, with no apparent recurrence.
eliminated by surgery in one eye and improved in the other three. Refractive astigmatism was unchanged in six eyes (46.2%), increased in four eyes (30.8%), and decreased in three eyes (23.1%). On the average, the astigmatism was increased by 0.19 diopter. Best corrected postoperative visual acuity was unchanged in eight eyes (61.5%), worse by one line in two eyes (15.4%), improved by one line in two eyes (15.4%), and improved by two lines in one eye (7.7%).
vestigators have not reported individual visual acuities and refractions. 7.14.16,20,22-27 Some reports of recurrent pterygium excision combined with either beta irradiation" or lamellar keratoplastyr'-" described no recurrences. In other series, the use of lamellar keratoplasty for recurrent pterygium resulted in recurrence rates of 31 %, 2330%,24 and 55%.4 A recent review of 41 cases of recurrent pterygium treated with free conjunctival autografts reported a recurrence rate of 7.3%.19 We believe that lamellar keratoplasty is useful in certain patients. In those with recurrence despite treatment with beta irradiation and conjunctival. graft, lamellar keratoplasty may prevent further recurrence. Also, lamellar keratoplasty after excision of the pterygium can restore the structural integrity of the globe in patients with thinned corneas. The visual results may be improved, particularly if the visual axis is involved by the pterygium, by providing a new Bowman's layer in the affected area, facilitating the formation of a smooth epithelialized surface. This may also reduce the rate of recurrence, because surface abnormalities in the limbal area may contribute to regrowth. Breaks in the continuity of the tear film cause localized drying and degenerative changes, which may stimulate vascular ingrowth. The use of precarved, preserved tissue in lamellar keratoplasty for recurrent pterygium makes the surgical procedure easier and shorter, and allows a good visual outcome. The advantages of lyophilized donor tissue over fresh tissue are that the preserved tissue can be stored for a minimum of two months and can be
Discussion The three main goals of successful pterygium surgery are to remove the pterygium safely, to obtain a good optical result, and to avoid recurrence. Recurrent lesions are especially difficult to treat. Removal of the recurrent pterygium is more hazardous because the underlying cornea may be very thin. Extensive scarring from previous procedures can adversely affect visual acuity and further recurrences are common. There is no uniformity of opinion about the preferred treatment for recurrent pterygia. Controlled studies comparing available treatments have not been performed. Comparison of results in reported series is difficult because of the lack of uniformity. Variations in recurrence rate reflect not only the effectiveness of the technique, but also variations in preoperative condition, length of follow-up, dropout rates, population, climate, occupation, and definition of recurrence. Additionally, most in-
Lyophilized Tissue for Pterygium
Vol. 102, No.2
used at any moment, should the surgeon decide intraoperatively to combine the pterygium excision with the lamellar keratoplasty procedure. Furthermore, since the tissue is prepared on a cryolathe, the posterior surface is smooth and the thickness is uniform compared with hand-dissected lamellar grafts. This also eliminates the technical problem of dissecting a corneal lamella from donor tissue and considerably shortens the time necessary for the surgery. The cost of the commercially prepared tissue, $700, is considerable and each surgeon must weigh the advantages of its use against this increased cost. The recurrence rate of 8% in this series compared favorably with other reports. The visual outcome in our series was good; in two cases visual acuity decreased by one line but in 11 cases there was an improvement or no change from preoperative values. The change in astigmatism was minimal, averaging less than 0.25 diopter. Only one of the 13 eyes required additional surgery for recurrence.
References 1. Kamel, 5.: Pterygium, its nature and a new line of treatment. Br. J. Ophthalmol. 30:549, 1946. 2. Escapini, H.: Pterygium excision. Am. J. Ophthalmol. 45:879, 1958. 3. Cameron, M. E.: Pterygium Throughout the World. Springfield, Charles C Thomas, 1965, pp. 141 and 171. 4. Pearlman, G., Susal, A. L., Hushaw, J., and Bartlett, R. E.: Recurrent pterygium and treatment with lamellar keratoplasty with presentation of a technique to limit recurrences. Ann. Ophthalmol. 2:763, 1970. 5. Zauberman, H.: Pterygium and its recurrence. Am. J. Ophthalmol. 63:1780, 1967. 6. Youngson, R. M.: Recurrence of pterygium after excision. Br. J. Ophthalmol. 56:120, 1972. 7. McReynolds, J. 0.: The nature and treatment of pterygia. J.A.M.A. 39:296, 1902. 8. Rosen, E.: Pterygium. Br. J. Ophthalmol32:300, 1948. 9. Neher, E. M.: A new method of transplanting pterygium. Arch. Ophthalmol. 21:30, 1939. 10. Bangerter, A.: Pterygium operation and covering of conjunctival defects. Ophthalmologica 106:316, 1943.
227
11. D'Ombrain, A.: Surgical treatment of pterygium. Br. J. Ophthalmol 32:65, 1948. 12. Sugar, H. 5.: A surgical treatment for pterygium based on new concepts as to its nature. Am. J. Ophthalmol. 32:912, 1949. 13. McGavic, J. 5.: Surgical treatment of recurrent pterygium. Arch. Ophthalmol. 42:726, 1949. 14. King, J. H.: The pterygium. Brief review and evaluation of certain methods of treatment. Arch. Ophthalmol. 44:854, 1950. 15. Campodonico. E.: A new procedure in the excision method of pterygium operation. In Zentmayer, W. (ed.): Transactions of the XII International Congress of Ophthalmology, Washington, D.C., 1922. Philadelphia, W. F. Fell, 1922, pp. 201-205. 16. Jacobi, K. W., and Krey, H.: Lamellare Keratoplastik und Bindehauttransposition bei Pterygium. Klin. Monatsbl. Augenheilkd. 167:206, 1975. 17. Dowlut, M.S., and Laflamme, M. Y.: Les pterygions recidivants. Frequence et correction par autogreffe conjonctivale. Can. J. Ophthalmol. 16:119, 1981. 18. Barraquer, J. 1.: Etiology, pathogenesis, and treatment ofthe pterygium. Transactions of the New Orleans Academy of Ophthalmology. St. Louis, C. V. Mosby, 1980, pp. 167-178. 19. Kenyon, K. R., Wagoner, M. D., and Hettinger, M. E.: Conjunctival autograft transplantation for advanced and recurrent pterygium. Ophthalmology 92:1461, 1985. 20. Magitot, A.: Etude critique sur certaines proprietes biologiques due tissue corneen et sur la keratoplastie humaine. Ann. Oculist. 153:417, 1916. 21. Pievse, D., and Casey, T. A.: Lamellar keratoplasty. Br. J. Ophthalmol 43:733, 1959. 22. Poirier, R. H., and Fish, J. R.: Lamellar keratoplasty for recurrent pterygium. Ophthalmic Surg. 7:38, 1976. 23. Hallermann, W., Schroder, G. M., and Salehi, A. N.: Ergebnisse der lamellaren Keratoplastik bei rezidivierenden Pterygien. Klin. Monatsbl. Augenheilkd. 171:191, 1977. 24. Laughrea, P. A., and Arentsen, J. J.: Lamellar keratoplasty in the management of recurrent pterygium. Ophthalmic Surg. 17:106, 1986. 25. Haik, G. M., Ellis, G. 5., and Nowell, J. F.: The management of pterygia with special reference to surgery combined with beta irradiation. Trans. Am. Acad. Ophthalmol. Otolaryngol. 66:776, 1962. 26. Beran, V.: Soucasna lamelarni a extrakornealni keratoplastika u recidivujicich pterygii. Cesk. Oftalmol. 40:36, 1984. 27. Monselise, M., Schwartz, M., Politi, F., and Barishak, Y. R.: Pterygium and beta irradiation. Acta Ophthalmol. 62:315, 1984.
Thirteen eyes with recurrent pterygia were treated with excision and lamellar keratoplasty using precarved, lyophilized donor cornea. After an average follow-up of 23 months, only one eye (7.7%) required repeat excision. Two eyes (15.4%) had minor recurrences that were asymptomatic and did not progress. Minimal vascularization at the interface between donor and recipient cornea was frequent, but this completely regressed after suture removal and topical corticosteroid treatment. Limitation of movement, when present preoperatively, was improved or eliminated. Best corrected visual acuity was unchanged in eight eyes (61.5%), decreased by one line in two eyes (15.4%), and improved by one or two lines in three eyes (23.1 %). Postoperative astigmatism was within 0.5 diopter of the preoperative value in 11 eyes (84.6%); one eye (7.7%) had a postoperative increase of 1 diopter and another eye (7.7%) of 2 diopters. REPORTED RATES Of recurrence of a pterygium after primary excision vary from 0% to 69%.1-3 However, the most recent reports indicate a recurrence rate of 37% to 44%.4-6 The likelihood of recurrence is higher in young patients and in those with marked activity preoperatively. 5 The treatment of recurrent pterygia is a problem that has not been solved despite the variety of surgical techniques used. Most investigators
Accepted for publication June 4, 1986. From the Lions Eye Research Laboratories, LSU Eye Center, Louisiana State University Medical Center School of Medicine, New Orleans, Louisiana. This study was supported in part by Public Health Service grants EY02580, EY07073, and EY02377 from the National Eye Institute and by a traveling scholarship from the Royal College of Surgeons Foundation, Inc., New York City (Dr. Halliday). Reprint requests to Marguerite B. McDonald, M.D., LSU Eye Center, 136 S. Roman St., New Orleans, LA 70112.
222
have not distinguished between approaches to primary pterygia and recurrent pterygia. Recommended techniques have included dissecting the pterygium from the surface of the cornea and burying the head,":" excision leaving a bare scleral area,":" and a conjunctival graft. 10,15-19 Lamellar keratoplasty for the treatment of pterygia was first described in 1916 by Magitot." Despite reports of its successful use,4,21-24 it has not been employed extensively, partly because of the complexity of the technique. Precarved, lyophilized tissue, which offers the potential for a simplified surgical technique, has been produced here since 1981, and has been available commercially since 1984. We have used carved and lyophilized donor tissue in lamellar keratoplasty for recurrent pterygia in 13 eyes of ten patients.
Subjects and Methods We reviewed retrospectively the records of all patients treated here who underwent excision of recurrent pterygium followed by lamellar keratoplasty with precarved, lyophilized tissue. All such patients with six or more months of follow-up were included. A total of ten patients (13 eyes) with an average of 23 months follow-up (range, six to 44 months) were examined (Table). There were nine men and one woman. The average age was 43 years (range, 30 to 66 years). All the patients were residents of southern states; three had predominantly outdoor occupations. All ten had had previous surgery, with an average of 2.2 pterygium removals from the affected eye. Two eyes (15.4%) had received mucous membrane grafts and eight (61.5%) had been treated with beta irradiation. Preoperative examination included determi-
©AMERICAN JOURNAL OF OPHTHALMOLOGY
102:222-227,
AUGUST,
1986
Vol. 102, No. 2
Lyophilized Tissue for Pterygium
223
Fig. 1 (Busin and associates). Schematic representation of lamellar keratoplasty for pterygium. The pterygium (top left) is dissected from the underlying corneal and conjunctival tissue (top right) and removed in toto. A partial-thickness, vertical incision is made at the central edge of the affected cornea, and a lamellar dissection (middle left) is performed, incorporating the entire area covered by the pterygium. The donor tissue is cut to the proper size and sutured into the corneal bed with 10-0 nylon interrupted sutures (middle right). Normal conjunctiva is used to cover the adjacent bare sclera (bottom left).
224
August, 1986
AMERICAN JOURNAL OF OPHTHALMOLOGY
TABLE SUMMARY OF CLINICAL DATA FOR TEN PATIENTS (13 EYES) WITH RECURRENT PTERYGIUM PREVIOUS TREATMENT PATIENT NO., SEX, AGE (VRS)
1, 2, 3, 4, 5,
M, 33 M, 44 F,50 M, 53 M, 25
6, M, 34 7, M, 44 8, M, 55 9, M, 52 10, M, 41
AFFECTED
MUCOUS MEMBRANE
SURGERY
VISUAL ACUITY
BETA IRRADIATION
GRAFT
(NO.)
PREOPERATIVE
POSTOPERATIVE
Left
No
Yes
Left
No
No
2 1
20/20 20/20
Left
Yes
No
Left
Yes
Yes
Right
Yes
No No
3 4 1 1
20/25 20/20 20/20 20/20 20/30
20/20 20/20 20/25
EYE
Left
Yes
Right
No
No
Right
Yes
No
Right
Yes
No
Left
Yes
No
Left
No
No
Right
No
No
3 3 2 2 2 2
Left
Yes
No
2
20/20 20/20 20/20 20/30 20/25 20/20
20/25 20/20 20/20 20/20 20/20 20/15 20/15 20/30 20/30 20/20
"Maximum extension into the cornea from the corneosclerallimbus. 'Vessels regressed completely after suture removal and topical corticosteroid therapy. INo symptomatic recurrence. Patient 1 had a fibrovascular ingrowth at the lower edge of the graft, extending about 1 mm into the cornea. Patient 6 had fibrovascular ingrowths superiorly and inferiorly. The ingrowths are stable in both cases. §After a recurrence the patient was treated elsewhere with excision and mucous membrane graft. Refraction was done after this second operation.
nation of visual acuity and refractive error, assessment of motility, and measurement, with drawings and photographs, of the pterygium. Surgery was performed under general (seven eyes; 53.8%) or local (six eyes; 46.2%) anesthesia. The pterygium was dissected from the cornea (Fig. 1, top left and top right) and a lamellar keratectomy was performed incorporating the entire area covered by pterygium (Fig. 1, middle left). This was accomplished first by the creation of a partial-thickness vertical incision in clear cornea, beginning just central to the head of the pterygium bed and extending above and below to the corneoscleral limbus. The conjunctival body of the pterygium was removed together with underlying scar tissue, freeing the adjacent rectus muscle if it appeared to be involved. In some cases a subconjunctival injection of local anesthetic was used to "balloon" the conjunctiva and make the dissection easier. Hemostasis was obtained with bipolar cautery. The precarved, lyophilized lenticule of corneal stroma has an intact Bowman's layer. It is shaped on a cryolathe from the endothelial surface to a uniform thickness of 0.3 mm, and
trephined to a diameter of 10.0 mm. The lens is rehydrated in a balanced salt solution containing gentamicin, 100 ug/rnl, for 20 minutes before use. Commercially prepared tissue was used in six eyes (46.2%) and locally prepared tissue in seven eyes (53.8%). At surgery, the tissue was cut to the proper size and sutured into the prepared corneal bed with 10-0 nylon interrupted sutures (Fig. 1, middle right). Normal conjunctiva was used to cover the bare sclera and restore limbal anatomy (Fig. 1, bottom left). If possible, a pedunculated flap was created from adjacent normal conjunctiva (ten eyes; 76.9%); otherwise, a free autograft was used (three eyes; 23.1%). The conjunctiva was sutured with 7-0 chromic catgut. Subconjunctival20-mg injections of gentamicin sulfate and 40-mg injections of methylprednisolone acetate were administered at the end of surgery, well away from the operative area. In six eyes (46.2%), a bandage contact lens was applied before the eye was patched and shielded. Postoperative antibiotic, mydriatic, and corticosteroid drugs were given as necessary. The bandage contact lens, when present, was re-
Vol. 102, No. 2
Lyophilized Tissue for Pterygium
225
TABLE (Continued)
REFRACTION PREOPERATIVE
0.00 +0.25 -1.00 + 2.00 -1.75 -2.25 +0.50 -2.25 -0.50 -0.50 -1.25 +1.75 -0.75
+ + + + + + + +
0.50 1.00 2.50 1.00 0.50 0.75 1.50 0.25
x x x x x x x x
25 60 105 115 90 90 180 10
+ 1.00 x 65 + 0.25 x 125 + 0.50 x 110
SIZE OF POSTOPERATIVE
0.00 +0.50 -1.50 +0.50
+ + + +
0.50 0.50 3.00 0.50
x x x x
PTERYGIUM
FOLLOW-UP
INTERFACE
(MM)'
(MOB)
VESSELS
3.0 5.0 6.0 3.5 4.0 4.0 4.0 3.0 3.0 2.0 3.0 3.5 2.0
6 15 15 6 44 44 6 9 34 34 38 38 6
Yes'
90 90 90§ 105
Unchanged Unchanged
-1.00 -2.25 -1.75 -1.75 0.00 -2.25 -1.75
+ 1.75 x 70 + 0.50 x 10
+ 0.75 x 75 + 1.25 x 110 + 2.50 x 90
moved when epithelial healing was complete, approximately four days after surgery.
Results There were no operative complications. Postoperative recovery was uneventful in all but one eye, with rapid graft and conjunctival flap healing. Corneal sutures were removed when healing appeared satisfactory. In general, one half of the 10-0 sutures were removed two weeks after surgery and the remainder after four weeks (Figs. 2 to 4). Vascularization in the plane between the donor and the host cornea occurred in nine of the 13 eyes (69.2%). The vessels did not extend into the cornea for more than 1 mm, and in all cases regression occurred after removal of the 10-0 sutures and treatment with topical corticosteroids. Postoperative complications requiring further surgery occurred in only one eye (7.7%) (Patient 3). In this patient the central edge of the lamellar graft folded under itself, and it was necessary to trim the edge and resuture the graft. Subsequently, a temporary tarsorrhaphy was required for epithelial healing. Three months later a symptomatic recurrence of the pterygium occurred, which was excised elsewhere with placement of a mucous membrane graft.
RECURRENCE
Yes'
NOl No
Yes'
Yes
Yes'
No No
Yes' Yes' Yes'
No
Yes' Yest
No
No No No NOl No No No No No No
Asymptomatic pterygium recurrence, requiring no further surgery, occurred in two additional eyes (15.4%). In Patient 1, a recurrence developed at the lower edge of the corneal lamellar graft, extending for about 1 mm into the cornea. It was treated with an argon laser and regressed over the next four months; it is currently stable. In Patient 6, fibrovascular tissue grew over the upper and lower edges of the lamellar graft approximately 2 mm into the cornea but progressed no farther. The preoperative limitation of movement from medial rectus muscle involvement, present preoperatively in four eyes (30.8%), was
Fig. 2 (Busin and associates). Case 1, two days after surgery.
226
AMERICAN JOURNAL OF OPHTHALMOLOGY
August, 1986
Fig. 3 (Busin and associates). Case 4, seven weeks after surgery. The sutures were removed one week previously.
Fig. 4 (Busin and associates). Case 7, eight months after surgery. The donor lamellar graft is clear, with no apparent recurrence.
eliminated by surgery in one eye and improved in the other three. Refractive astigmatism was unchanged in six eyes (46.2%), increased in four eyes (30.8%), and decreased in three eyes (23.1%). On the average, the astigmatism was increased by 0.19 diopter. Best corrected postoperative visual acuity was unchanged in eight eyes (61.5%), worse by one line in two eyes (15.4%), improved by one line in two eyes (15.4%), and improved by two lines in one eye (7.7%).
vestigators have not reported individual visual acuities and refractions. 7.14.16,20,22-27 Some reports of recurrent pterygium excision combined with either beta irradiation" or lamellar keratoplastyr'-" described no recurrences. In other series, the use of lamellar keratoplasty for recurrent pterygium resulted in recurrence rates of 31 %, 2330%,24 and 55%.4 A recent review of 41 cases of recurrent pterygium treated with free conjunctival autografts reported a recurrence rate of 7.3%.19 We believe that lamellar keratoplasty is useful in certain patients. In those with recurrence despite treatment with beta irradiation and conjunctival. graft, lamellar keratoplasty may prevent further recurrence. Also, lamellar keratoplasty after excision of the pterygium can restore the structural integrity of the globe in patients with thinned corneas. The visual results may be improved, particularly if the visual axis is involved by the pterygium, by providing a new Bowman's layer in the affected area, facilitating the formation of a smooth epithelialized surface. This may also reduce the rate of recurrence, because surface abnormalities in the limbal area may contribute to regrowth. Breaks in the continuity of the tear film cause localized drying and degenerative changes, which may stimulate vascular ingrowth. The use of precarved, preserved tissue in lamellar keratoplasty for recurrent pterygium makes the surgical procedure easier and shorter, and allows a good visual outcome. The advantages of lyophilized donor tissue over fresh tissue are that the preserved tissue can be stored for a minimum of two months and can be
Discussion The three main goals of successful pterygium surgery are to remove the pterygium safely, to obtain a good optical result, and to avoid recurrence. Recurrent lesions are especially difficult to treat. Removal of the recurrent pterygium is more hazardous because the underlying cornea may be very thin. Extensive scarring from previous procedures can adversely affect visual acuity and further recurrences are common. There is no uniformity of opinion about the preferred treatment for recurrent pterygia. Controlled studies comparing available treatments have not been performed. Comparison of results in reported series is difficult because of the lack of uniformity. Variations in recurrence rate reflect not only the effectiveness of the technique, but also variations in preoperative condition, length of follow-up, dropout rates, population, climate, occupation, and definition of recurrence. Additionally, most in-
Lyophilized Tissue for Pterygium
Vol. 102, No.2
used at any moment, should the surgeon decide intraoperatively to combine the pterygium excision with the lamellar keratoplasty procedure. Furthermore, since the tissue is prepared on a cryolathe, the posterior surface is smooth and the thickness is uniform compared with hand-dissected lamellar grafts. This also eliminates the technical problem of dissecting a corneal lamella from donor tissue and considerably shortens the time necessary for the surgery. The cost of the commercially prepared tissue, $700, is considerable and each surgeon must weigh the advantages of its use against this increased cost. The recurrence rate of 8% in this series compared favorably with other reports. The visual outcome in our series was good; in two cases visual acuity decreased by one line but in 11 cases there was an improvement or no change from preoperative values. The change in astigmatism was minimal, averaging less than 0.25 diopter. Only one of the 13 eyes required additional surgery for recurrence.
References 1. Kamel, 5.: Pterygium, its nature and a new line of treatment. Br. J. Ophthalmol. 30:549, 1946. 2. Escapini, H.: Pterygium excision. Am. J. Ophthalmol. 45:879, 1958. 3. Cameron, M. E.: Pterygium Throughout the World. Springfield, Charles C Thomas, 1965, pp. 141 and 171. 4. Pearlman, G., Susal, A. L., Hushaw, J., and Bartlett, R. E.: Recurrent pterygium and treatment with lamellar keratoplasty with presentation of a technique to limit recurrences. Ann. Ophthalmol. 2:763, 1970. 5. Zauberman, H.: Pterygium and its recurrence. Am. J. Ophthalmol. 63:1780, 1967. 6. Youngson, R. M.: Recurrence of pterygium after excision. Br. J. Ophthalmol. 56:120, 1972. 7. McReynolds, J. 0.: The nature and treatment of pterygia. J.A.M.A. 39:296, 1902. 8. Rosen, E.: Pterygium. Br. J. Ophthalmol32:300, 1948. 9. Neher, E. M.: A new method of transplanting pterygium. Arch. Ophthalmol. 21:30, 1939. 10. Bangerter, A.: Pterygium operation and covering of conjunctival defects. Ophthalmologica 106:316, 1943.
227
11. D'Ombrain, A.: Surgical treatment of pterygium. Br. J. Ophthalmol 32:65, 1948. 12. Sugar, H. 5.: A surgical treatment for pterygium based on new concepts as to its nature. Am. J. Ophthalmol. 32:912, 1949. 13. McGavic, J. 5.: Surgical treatment of recurrent pterygium. Arch. Ophthalmol. 42:726, 1949. 14. King, J. H.: The pterygium. Brief review and evaluation of certain methods of treatment. Arch. Ophthalmol. 44:854, 1950. 15. Campodonico. E.: A new procedure in the excision method of pterygium operation. In Zentmayer, W. (ed.): Transactions of the XII International Congress of Ophthalmology, Washington, D.C., 1922. Philadelphia, W. F. Fell, 1922, pp. 201-205. 16. Jacobi, K. W., and Krey, H.: Lamellare Keratoplastik und Bindehauttransposition bei Pterygium. Klin. Monatsbl. Augenheilkd. 167:206, 1975. 17. Dowlut, M.S., and Laflamme, M. Y.: Les pterygions recidivants. Frequence et correction par autogreffe conjonctivale. Can. J. Ophthalmol. 16:119, 1981. 18. Barraquer, J. 1.: Etiology, pathogenesis, and treatment ofthe pterygium. Transactions of the New Orleans Academy of Ophthalmology. St. Louis, C. V. Mosby, 1980, pp. 167-178. 19. Kenyon, K. R., Wagoner, M. D., and Hettinger, M. E.: Conjunctival autograft transplantation for advanced and recurrent pterygium. Ophthalmology 92:1461, 1985. 20. Magitot, A.: Etude critique sur certaines proprietes biologiques due tissue corneen et sur la keratoplastie humaine. Ann. Oculist. 153:417, 1916. 21. Pievse, D., and Casey, T. A.: Lamellar keratoplasty. Br. J. Ophthalmol 43:733, 1959. 22. Poirier, R. H., and Fish, J. R.: Lamellar keratoplasty for recurrent pterygium. Ophthalmic Surg. 7:38, 1976. 23. Hallermann, W., Schroder, G. M., and Salehi, A. N.: Ergebnisse der lamellaren Keratoplastik bei rezidivierenden Pterygien. Klin. Monatsbl. Augenheilkd. 171:191, 1977. 24. Laughrea, P. A., and Arentsen, J. J.: Lamellar keratoplasty in the management of recurrent pterygium. Ophthalmic Surg. 17:106, 1986. 25. Haik, G. M., Ellis, G. 5., and Nowell, J. F.: The management of pterygia with special reference to surgery combined with beta irradiation. Trans. Am. Acad. Ophthalmol. Otolaryngol. 66:776, 1962. 26. Beran, V.: Soucasna lamelarni a extrakornealni keratoplastika u recidivujicich pterygii. Cesk. Oftalmol. 40:36, 1984. 27. Monselise, M., Schwartz, M., Politi, F., and Barishak, Y. R.: Pterygium and beta irradiation. Acta Ophthalmol. 62:315, 1984.