PTERYGIUM

Many Americans unaware of UV ray damage to eyesAnonymous. Ophthalmology Times. Cleveland: Jun 15, 2007. Vol. 32, Iss. 12; pg. 42, 1 pgs

Abstract (Summary)

Extended UV exposure has been linked to eye damage, including cataract, age-related macular degeneration, pterygium, and photokeratitis.

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 (215  words)Copyright Advanstar Communications, Inc. Jun 15, 2007

FROM STAFF REPORTS

Chicago-Although many in the United States may know the harmful effects that ultraviolet (UV) rays can have on the skin, few are aware of the damage they can cause to the eyes. Perhaps the most frightening aspect of UV damage is that it is cumulative, meaning the negative effects may not present themselves until years later.

"Most of us would not dream of staying outside in the sun without putting on sunscreen lotion," said Daniel D. Garrett, senior vice president of Prevent Blindness America (PBA). "But we also have to remember to wear both UV-blocking lenses and a brimmed hat to protect our eyes as well."

PBA has launched a dedicated online resource for patients and their loved ones to learn more about what they can do to protect their eyes. The Web site, www.preventblindness.org/uv, offers a variety of tools and information on everything from risk factors to buying tips for sunglasses for adults and children. The site was made possible by a grant through the Transitions Healthy Sight for Life Fund.

Extended UV exposure has been linked to eye damage, including cataract, age-related macular degeneration, pterygium, and photokeratitis.

For more information on the dangers of UV exposure and how to choose the best options, go to www. preventblindness.org/uv or call 800/331-2020.

Indexing (document details)

Subjects: Macular degeneration,  Ultraviolet radiation

305 PQ REVERSE_CHRON 1283785446

Author(s): Anonymous

Document types:

News

Section: Cataract

Publication title:

Ophthalmology Times. Cleveland: Jun 15, 2007. Vol. 32, Iss. 12;  pg. 42, 1 pgs

Source type: Periodical

ISSN: 0193032X

ProQuest document ID:

1311007131

Text Word Count

215

Document URL:

http://proquest.umi.com/pqdweb?did=1311007131&sid=2&Fmt=3&clientId=98602&RQT=309&VName=PQD

Pterygium (conjunctiva)From Wikipedia, the free encyclopedia

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Pterygium (conjunctiva)

Classification and external resources

Pterygium removal surgery

ICD-10 H 11.0

ICD-9 372.4

DiseasesDB 10916

MedlinePlus 001011

eMedicine oph/542

MeSH D011625

Pterygium most often refers to a benign growth of the conjunctiva. A pterygium commonly grows from the nasal side of the sclera. It is associated with, and thought to be caused by ultraviolet-light exposure (e.g. sunlight), low humidity, and dust. The predominance of pterygia on the nasal side is possibly a result of the sun's rays passing laterally through the cornea where it undergoes refraction and becomes focused on the limbic area. Sunlight passes unobstructed from the lateral side of the eye, focusing on the medial limbus after passing through the cornea. On the contralateral (medial) side, however, the shadow of the nose medially reduces the intensity of sunlight focused on the lateral/temporal limbus.[1]

Contents

[hide]

1 Pathology 2 Prevention 3 Symptoms 4 Treatment 5 See also 6 References 7 External links

[edit] Pathology

Pterygium growing onto the cornea

Pterygium in the conjunctiva is characterized by elastotic degeneration of collagen (actinic elastosis [2] ) and fibrovascular proliferation. It has an advancing portion called the head of the pterygium, which is connected to the main body of the pterygium by the neck. Sometimes a line of iron deposition can be seen adjacent to the head of the pterygium called Stocker's line. The location of the line can give an indication of the pattern of growth.

The exact cause is unknown, but it is associated with excessive exposure to wind, sunlight, or sand. Therefore, it is more likely to occur in populations that inhabit the areas near the equator, as well as windy locations. Additionally, pterygia are twice as likely to occur in men than women.

Some research also suggests a genetic predisposition due to an expression of vimentin, which indicates cellular migration by the keratoblasts embryological development, which are the cells that give rise to the layers of the cornea. These cells also exhibit an increased P53 expression likely due to a deficit in the tumor suppressor gene. These indications

give the impression of a migrating limbus because the cellular origin of the pterygium is actually initiated by the limbal epithelium. [3]

Anatomically, the pterygium is composed of several segments:

Fuchs' Patches (minute gray blemishes that disperse near the pterygium head). Stocker's Line (a brownish line composed of iron deposits). Hood (fibrous nonvascular portion of the pterygium). Head (apex of the pterygium, typically raised and highly vascular). Body (fleshy elevated portion congested with tortuous vessels). Superior Edge (upper edge of the triangular or wing shaped portion of the pterygium). Inferior Edge (lower edge of the triangular or wing shaped portion of the ptyerygium).

[edit] Prevention

As it is associated with excessive sun or wind exposure, wearing protective sunglasses with side shields and/or wide brimmed hats and using artificial tears throughout the day may help prevent their formation or stop further growth. Surfers and other water-sport athletes should wear eye protection that block 100% of the UV rays from the water, as is often used by snow-sport athletes.

[edit] Symptoms

Symptoms of pterygium include persistent redness, inflammation, foreign body sensation, dry and itchy eyes. In advanced cases the pterygium can affect vision as it invades the cornea with the potential of obscuring the optical center of the cornea and inducing astigmatism and corneal scarring.[4][5]

[edit] Treatment

Today a variety of options are available for the management of pterygium, from irradiation, to conjunctival auto-grafting or amniotic membrane transplantation, along with glue and suture application. As it is a benign growth, pterygium typically does not require surgery unless it grows to such an extent that it covers the pupil, obstructing vision or presents with acute symptoms. Some of the irritating symptoms can be addressed with artificial tears. However, no reliable medical treatment exists to reduce or even prevent pterygium progression. Definitive treatment is achieved only by surgical removal. Long-term follow up is required as pterygium may recur even after complete surgical correction.

If there is recurrence after surgery or if recurrence of pterygium is thought to be vision threatening, it is possible to use strontium ( 90 Sr) plaque therapy. 90 Sr is a radioactive substance that produces beta particles which penetrate a very short distance into the cornea at the site of the operation. It suppresses the regrowth of blood vessels that occur

with return of the pterygium. The treatment requires some local anaesthetic in the eye and is best done at the time of, or on the same day as the pterygium excision.

The 90 Sr plaque is a concave metal disc about 1-1.5cm in diameter which is hollow and filled with an insoluble strontium salt. The side placed on the eye is a very thin and delicate silver film that will contain the strontium but allow the beta particles to escape. The dose of radiation to the conjunctiva is controlled by the time that the plaque is left in contact with the surface. The integrity of the plaque surfaces is paramount to prevent exposure to patients and so is wipe tested to see if radioactive matter is escaping. Obviously this test must be done very very gently.

Conjunctival auto-grafting is a surgical technique that is effective and safe procedure for pterygium removal. When the pterygium is removed the tissue that covers the sclera known as the conjunctiva is also extracted, auto-grafting replaces the bare sclera with tissue that is surgically removed from the inside of the patients’ upper eyelid. That “self-tissue” is then transplanted to the bare sclera and is fixated using sutures, tissue adhesive, or glue adhesive.

Amniotic membrane transplantation is an effective and safe procedure for pterygium removal. Amniotic membrane transplantation offers practical alternative to conjunctival auto graft transplantation for extensive pterygium removal. Amniotic membrane transplantation is tissue that is acquired from the innermost layer of the human placenta and has been used to replace and heal damaged mucosal surfaces including successful reconstruction of the ocular surface. It has been used as a surgical material since the 1940s, and has been shown to have a strong anti-adhesive effect. [6] [7] Using an amniotic graft facilitates epithelialization, and has anti-inflammatory as well as surface rejuvenation properties. Amniotic membrane transplantation can also be fixated to the sclera using sutures, or glue adhesive.[8] [9] [10] [11] [12] Amniotic membrane transplantation with Tisseel glue application and Mitomycin-C has shown excellent cosmetic outcomes with a surface free of redness, stitching, or patches which makes the ocular surface suitable for vision correction surgery sooner.[13] [14] [15]

Preserved human amniotic membrane transplantation in the treatment of primary pterygiumNalan Fatma Tekin, Suleyman Kaynak, Ali Osman Saatci, Guray Cingil. Ophthalmic Surgery and Lasers. Thorofare: Nov/Dec 2001. Vol. 32, Iss. 6; pg. 464, 6 pgs

Abstract (Summary)

BACKGROUND AND OBJECTIVE: To assess the outcome of simple excision with preserved human amniotic membrane transplantation in the treatment of primary pterygium. PATIENTS AND METHODS: A total of 59 eyes with primary pterygium underwent surgical excision. In Group 1, 28 eyes were treated with simple excision and preserved human amniotic membrane transplantation. In Group 2, 31 eyes were treated with bare sclera excision. These two groups were compared in recurrence, final appearance of the operation site, and complications. Patients were followed for at least 10 months. RESULTS: During a mean follow up of 14.9 months, we observed 3 (10.7%) recurrences in Group 1 and 20 (38.7%) recurrences in Group 2 (P:0.03). In Group 1, 20 (71.4%) eyes and 14 (45.2%) eyes in Group 2 had a satisfactory final operation site appearance (P:0.041). No serious complication was observed in both groups. CONCLUSION: Simple excision and preserved human amniotic membrane transplantation appears to be a safe and effective way of treating primary pterygium because of the lack of serious complications and a relatively low rate of recurrence.

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 (2697  words)Copyright Slack, Incorporated Nov/Dec 2001

[Headnote]* BACKGROUND AND OBJECTIVE: To assess the outcome of simple excision with preserved human amniotic membrane transplantation in the treatment of primary pterygium. m PATIENTS AND METHODS: A total of 59 eyes with primary pterygium underwent surgical excision. In Group 1, 28 eyes were treated with simple excision and preserved human amniotic membrane transplantation. In Group 2, 31 eyes were treated with bare sclera excision. These two groups were compared in recurrence, final appearance of the operation site, and complications. Patients were followed for at least 10 months.

[Headnote]* RESULTS: During a mean follow up of 14.9 months, we observed 3 (10.7%) recurrences in Group 1 and 20 (38.7%) recurrences in Group 2 (P:0.03). In Group 1, 20 (71.4%) eyes and 14 (45.2%) eyes in Group 2 had a satisfactory final operation site appearance (P:0.041). No serious complication was observed in both groups.

0 CONCLUSION: Simple excision and preserved human amniotic membrane transplantation appears to be a safe and effective way of treating primary pterygium because of the lack of serious complications and a relatively low rate of recurrence. [Ophthalmic Surg Lasers 2001;32:464-4691

INTRODUCTION It continues to be a challenge for ophthalmic surgeons to prevent the recurrence of pterygium following surgical excision despite various surgical techniques and adjunctive treatments. The use of antifibrotic agents, thiotepa or beta irradiation in adjunct to surgery reduced the recurrence rates. However, as some serious complications were reported after these treatments, concerns about safty have arisen.l-11 The application of Er:YAG or excimer laser in the treatment of pterygium is fraught with problems because of the size of the system, collateral damage to the surrounding tissue, or high recurrence rates."2-"4 Conjunctival autografting, which appears to be a safe and effective way of treating pterygium, is usually reserved for patients with recurrences or advanced disease to preserve the remaining healthy conjunctiva.1,15-19

Recently, Prabhasawat et a115 first reported the use of preserved human amniotic membrane transplantation in treatment of primary and recurrent pterygium with a relatively low recurrence rate and without serious complications. In this study, the processed and preserved amniotic membrane seemed to have a beneficial effect in promoting healthy epithelial wound healing and preventing recurrence of pterygium. Amniotic membrane transplantation has also been used in conjunction with limbal autograft for recurrent pterygium associated with symblepharon.20 Results of this study are also encouraging, with no recurrence of symblepharon in any of the patients, a high rate of remission of pterygium regrowth, and improvement of ocular movements in all cases. In the current study, we examined the outcome of simple excision and preserved amniotic membrane grafting in treatment of primary pterygium.

PATIENTS AND METHODS Patients

We consecutively performed simple excision fol

lowed by amniotic membrane grafting in 28 eyes of 27 patients with primary pterygium (23 nasal, 5 temporal pterygium) and bare sclera excision in 31 eyes of 27 patients with primary pterygium (24 nasal, 7 temporal pterygium) at Dokuz Eylul University Department of Ophthalmology between 1996 and 1998. All surgical procedures were performed by the same surgeon (NFT). Cases with recurrent pterygium were not included in this study.

Patient selection was done according to presence of one or more of the following criteria: reduced vision due to astigmatism or visual axis impairment by pterygia; moderate to severe ocular surface irregularityrelated signs and symptoms like hyperemia, burning, foreign body sensation; restriction of ocular motility, with or without diplopia; and cosmetic reasons.

Patients were followed for at least 10 months and colored anterior segment pictures were taken at each follow-up visit. Similar to a previously described grading,15 the last appearance of the operation site was graded as: Grade 1-Totally normal appearing anterior segment or presence of fine episcleral vessels on the operation site not extending beyond limbus; Grade 2-Vascular and additional apparent fibrous tissue proliferation not invading cornea; and Grade 3Fibrovascular tissue proliferation invading cornea (frank recurrence). Grade 1 was considered a satisfactory outcome. Preparation of the Amniotic Membrane

Human amniotic membrane was prepared and preserved as described previously15 with minor modifications. Human placenta was obtained from mothers who were detected as negative for syphilis, HIV, hepatitis B and C. The placenta was washed and cleaned out of blood particles with PBS (phosphate buffered solution) containing 50 mg/mL penicillin, 50 mg/mL streptomycin, 100 mg/mL neomycin, and 2.5 mg/mL amphotericin B. The amniotic membrane was dissected from the underlying chorion by blunt dissection and laid over a 0.45 pm nitrocellulose paper with the epithelial surface up. The membrane with the underlying nitrocellulose paper was cut into 5 X 5 cm disks and placed in sterile vials containing RPMI 1640 medium (Flow Lab. Ltd., U.K.) and glycerol (1:1), then stored at -80 C before surgery. Surgical Technique

Following peribulbar anesthesia with 2% lidocaine and 0.5% bupivacaine, all eyes were prepared and draped in a sterile fashion. After insertion of a lid speculum, the pterygium head was dissected from the cornea with a #15 blade and its corpus was trimmed up to 5 mm away from the limbus. Subconjuctival fibrous tissue adjacent to the pterygium was removed in an area much more than the pterygium body itself, which was limited by nasal caruncle for nasal pterygium. Minimal cauterization was applied to the exposed episcleral vessels. In the amniotic membrane group, the amniotic membrane was removed from the storage medium, then cut and trimmed to cover the defect area. The membrane with the epithelial side up was secured to the adjacent healthy conjunctiva by running 8.0 Vicryl suture, and to the cornea by interrupted 10.0 nylon sutures when necessary. In the bare sclera group, the remaining healthy conjunctiva was released and pulled together, and closed by interrupted 8.0 Vicryl sutures leaving 3 mm bare sclera from the limbus.

All patients received 1% prednisolone acetate eye drops every hour for two days, which was tapered in one month, and 0.3% tobramycine eye drop qid for two weeks.

RESULTS There was no statistical difference in age, gender, and bilaterality between the two groups (Table 1). The mean follow up was 11.9 + 1.4 and 17.7 + 5.0 months for Group 1 and Group 2, respectively (P <0.0001). The recurrence rate following amniotic membrane grafting was 10.7% (3 of 28 eyes), which was significantly lower than the 38.7% (12 of 31 eyes) of the bare sclera excision (PO.03). All recurrences developed between three to six months after surgery. In Group 1, 20 of 28 eyes (71.4%) ended up with a satisfactory final appearance postoperatively (Grade 1), which was comparable to 45.2% (14 of 31 eyes) of Group 2 (PO.041). Besides minor complications, no serious complication was observed in any patient (Table 2). Dissolution of the amniotic

membrane was observed in 3 eyes (10%), three to five weeks following surgery. These membranes gradually lost their transparency and became more opaque prior to dissolution (Figures 1 and 2).

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Table 1.

DISCUSSION The main goal of treatment for eyes with pterygium is to achieve a permanently healthy and cosmetically acceptable ocular surface without recurrence of pterygium.2' However, recurrence could not totally be prevented despite various surgical techniques and adjunctive treatments (Table 3). Even some treatment modalities may be fraught with serious sight-threatening complications such as scleral ulceration, scleromalacia and corneal perforation.'- Conjunctival autografting following surgical excision of the pterygium seems to achieve promising surgical outcomes with low recurrence rates and without serious complications.1,15-19 However, this technique sacrifices the remaining healthy conjunctiva that may be vital for further eye procedures. Thus, amniotic membrane grafting may be a viable option.

The use of amniotic membrane in ophthalmology was first reported by de Rotth22 in 1979. In this study, live amniotic membrane, which also included chorion, was used in the surgical treatment of symblepharon in 6 patients. Despite the initial successful anatomic appearance, all membranes, except one, dissolved and disapeared in a very short time. Although not proven histologically, their poor outcome might be attributed to the use of live rather than a preserved amniotic membrane and/or the presence of chorion in the transplanted tissue, leading to subsequent allograft rejection. In 1995, Kim and Tseng23 reintroduced the use of amniotic membrane that was separated from the chorion, processed, and then preserved. Results of later studies using preserved membrane in a variety of ocular disorders are encouraging.15,20,23-28 In these studies, the risk of any adverse effect, such as allograft rejection, was avoided by using a substrate without live cells. Amniotic membrane seems to have a beneficial effect in promoting healthy and rapid wound healing in the treatment of pterygia, conjunctival lesions and scars, symblepharon, persistent corneal epithelial defects with ulceration, deep corneal ulcers, chemical and thermal burns, ocular cicatricial pemphigoid, and Stevens-Johnson syndrome.15,20,23-28 Besides, the reconstructed surface shows reduced inflammation and reduced scarring.20,28 Interestingly, Lee and Tseng25 reported dissolution of the membrane in 5 of 11 eyes following preserved amniotic membrane grafting for the treatment of persistent epithelial defects with ulceration.15 Except for one, epithelization lasted in all other patients. Growth factors that are present in the preserved amniotic membrane might be liberated following dissolution and have stimulated healthy wound healing.29 In our series, we observed dissolution of the membrane in 3 eyes, 3 to 5 weeks following grafting. In the long-term follow up, only 1 of these 3 eyes experienced recurrence. The absence of recurrence in the other 2 eyes led us to think the possibility of

an ongoing beneficial effect after dissolution. Spontaneous dissolution phenomenon should be the subject of other prospective studies focusing on ultrastructural examination.

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Table 2.

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[Photograph]Figure 1.

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[Photograph]Figure 2.

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Table 3.

In the current study, amniotic membrane grafting following simple excision of primary pterygium resulted in a 10.7% probability of recurrence, compared with 38.7% for bare sclera excision. The great variations in recurrence rates, even among different studies using the same surgical procedure, can be explained by demographic differences and variations of the same surgical technique. Our two groups shared similar characteristics that enabled us to make a healthier comparision among the two distinct surgical techniques (Table 1). Also, as all surgeries were performed by a single surgeon, the amount of subconjunctival tissue removal and extent of cauterization were virtually alike. In a similar study, there was a 10.9% recurrence rate following amniotic membrane grafting with simple excision of primary pterygium.15 This result is similar to our rate because surgical technique, preservation method, and processing of amniotic membrane were alike.

Besides recurrence rate, operated eyes were also graded according to the final appearance of the operation site. Satisfactory final appearance (grade 1) was present in 71.4% of eyes in the amniotic membrane group, which was significantly higher than the 45.2% of the bare sclera group. This finding seems to support previous speculations about the role of the amniotic membrane in promoting healthy epithelial wound healing with reduced inflammation and scarring. 15,20,23-28

In the two studies using preserved amniotic membrane for treating pterygia (current studyl5), except for minor complications, no sight-threatening complication developed (Table 2). Although being effective in preventing recurrence of pterygium, treatment with mitomycin C, beta irradiation, and thiotepa may result in serious complications like uveitis, secondary glaucoma, cataract, scleral ulceration and necrosis, scleromalacia, corneal ulceration, corneal melting and perforation, bacterial corneoscleritis, fungal panophthalmitis, bacterial corneoscleritis, and skin depigmentation.1-7,11 In this aspect, amniotic membrane grafting seems to achieve relatively low recurrence rates, without injuring otherwise healthy eyes.

Because of the latest preservation techniques, amniotic membrane transplantation is feasible anytime necessary. Besides the efficiency in preventing frank recurrence, amniotic membrane grafting following simple excision appears to be an easy, safe,

cosmetically satisfying, and efficient way of treating pterygium without jeopardizing the remaining healthy conjunctiva and the eye.

[Reference] REFERENCES

[Reference] 1. Waller SG, Adamis AP Pterygium. In: Parks MM, Mitchell PR, eds. Duane's Ophthalmology (on CDROM). Philadelphia: J.B. Lippincott; 1995: vol 6, chap 35. 2. Adamis AP, Starck T, Kenyon KR. The management of pterygium. Ophthalmol Clin North Am. 1990;3:611 623. 3. Farrell PLR, Smith RE. Bacterial corneoscleritis complicating pterygium excision. Am J Ophthalmol. 1989;107:515-517. 4. Ewing-Chow DA, Romanchuk KG, Gilmour GR, Underhill JH, Climenhaga DB. Corneal melting after pterygium removal followed by topical mitomycin C therapy. Can J Ophthalmol. 1992;27:197-199. 5. Rubinfeld RS, Pfister RR, Stein RM, Foster CS, Martin NF, et al. Serious complications of topical mitomycin-C after pterygium surgery. Ophthalmology. 1992;99:1647-1654.

[Reference] 6. Gupta S, Basti S. Corneoscleral, ciliary body, and vitreoretinal toxicity after excessive instillation of mitomycin C. Am J Ophthalmol 1992;114:503-504. 7. Tarr KH, Constable IJ. Late complications of pterygium treatment. BrJ Ophthalmol 1980;64:496-505. 8. Aswad MI, Baum J. Optimal time for postoperative irradiation of pterygia. Ophthalmology. 1987;94:14501451. 9. Nowell JE Management of pterygia 20 years later. South MedJ 1986;79:1382-1384. 10. de Keizer RJW, Swart-van den Berg M, Baartse WJ. Results of pterygium excision with Sr 90 irradiation, lamellar keratoplasty, and conjunctival flaps. Doc Ophthalmol. 1987;67:33-44. 11. MacKenzie FD, Hirst LW, Kynaston B, Bain C.

[Reference] Recurrence rate and complications after beta irradiation for pterygia. Ophthalmology. 1991;98:1776-1781. 12. Nakamura K, Bissen-Miyajima H, Shimmura S, Tsubota KI Clinical application of Er:YAG laser for the treatment of pterygium. Ophthalmic Surg Lasers. 2000;31:8-12. 13. Forster W, Atzler U, Ratkay I, Busse H. Therapeutic use of the 193-nm excimer laser in corneal pathologies. Graefes Arch Clin Exp Ophthalmol. 1997;235:296-305. 14. Krag S, Ehlers N. Excimer laser treatment of pterygium. Acta Ophthalmol 1992;70:530-533. 15. Prabhasawat P, Barton K, Burkett G, Tseng SCG. Comparison of conjunctival autografts, amniotic membrane grafts, and primary closure for pterygium excision. Ophthalmology. 1997;104:974-985. 16. Tan DTH, Chee SP, Dear KBG, Lim ASM. Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with bare

sclera excision. Arch Ophthalmol. 1997;115:1235-1240.

[Reference] 17. Kenyon KR, Wagoner MD, Hettinger ME. Conjunctival autograft transplantation for advanced and recurrent pterygium. Ophthalmology. 1985;92: 1461-1470. 18. Riordan-Eva P, Kielhorn I, Ficker LA, Steele ADM, Kirkness CM. Conjunctival autografting in the surgical management of pterygium. Eye. 1993;7:634-638. 19. Starck T, Kenyon KR, Serrano E Conjunctival autograft for primary and recurrent pterygia: surgical technique and problem management. Cornea. 1991;10: 196-202. 20. Shimazaki J, Shinozaki N, Tsubota K. Transplantation of amniotic membrane and limbal autograft for patients with recurrent pterygium associated with symblepharon. BrJ Ophthalmol. 1998;82:235-240. 21. Hirst LW, Sebban A, Chant D. Pterygium recurrence time. Ophthalmology. 1994;101:755-758. 22. Treflford JD, Trelford-Sauder M. The amnion in surgery, past and present. Am J Obstet Gynecol. 1979;134:833-845. 23. Kim JC, Tseng SCG. Transplantation of preserved human amniotic membrane for surface reconstruction in severely damaged rabbit corneas. Cornea. 1995;

[Reference] 14:473-484. 24. Tseng SCG, Prabhasawat P, Lee S. Amniotic membrane transplantation for conjunctival surface reconstruction. Am J Ophthalmol. 1997; 124:765-774. 25. Lee SH, Tseng SCG. Amniotic membrane transplantation for persistent epithelial defects with ulceration. Am J Ophthalmol. 1997;123:303-312. 26. Shimazaki J, Yang HY, Tsubota K. Amniotic membrane transplantation for ocular surface reconstruction in patients with chemical and thermal burns. Ophthalmology. 1997;104:2068-2076. 27. Tsubota K, Satake Y, Ohyama M, Toda I, Takano Y, et al. Surgical reconstruction of the ocular surface in advanced ocular cicatricial pemphigoid and StevensJohnson syndrome. Am J Ophthalmol. 1996;122:3852. 28. Kruse FE, Rohrschneider K, Volcker HE. Multilayer amniotic membrane transplantation for reconstruction of deep corneal ulcers. Ophthalmology. 1999;106: 1504-1510.

[Reference] 29. Koizumi NJ, Inatomi TJ, Sotozono CJ, Fullwood NJ, Quantock AJ, et al. Growth factor mRNA and protein in preserved human amniotic membrane. Curr Eye Res. 2000;20:173-177. 30. Singh G, Wilson MR, Foster CS. Mitomycin eye drops as treatment for pterygium. Ophthalmology. 1988;95: 813-820. 31. Cardillo JA, Alves MR, Ambrosio LE, Poterio MB, Jose NK. Single intraoperative application versus postoperative mitomycin C eye drops in pterygium surgery. Ophthalmology. 1995;102:1949-1952. 32. Manning CA, Kloess PM, Diaz MD, Yee RW. Intraoperative mitomycin in primary

pterygium excision. Ophthalmology. 1997;104:844-848. 33. Chen PP, Ariyasu RG, Daza V, LaBree LD, McDonnell PJ. A randomized trial comparing mitomycin C and conjunctival autograft after excision of primary pterygium. Am J Ophthalmol. 1995;120:151-160. 34. Ngoy D, Kayembe L. Comparative study of mitomycin C and thio-tepa in the treatment of pterygium. Preliminary study. JFr Ophthalmol. 1998;21:96-102. 35. Krag S, Ehlers N. Excimer laser treatment of pterygium. Acta Ophthalmol. 1992;70:530-533.

[Author Affiliation]Nalan Fatma Tekin, MD; Suleyman Kaynak, MD; Ali Osman Saatci, MD; Guray Cingil, MD

[Author Affiliation]From the Department of Ophthalmology, Dokuz Eylul University, Izmir, Turkey.

[Author Affiliation]Accepted for publication April 9, 2001. Address reprint requests to Suleyman Kaynak, MD, Retina Goz Hastaliklari Arastirma ve Tedavi Merkezi, 1388 sok. No:16/A, 35220 Alsancak, Turkey [email: [email protected]].

Indexing (document details)

MeSH subjects: Adolescence,  Adult,  Aged,  Amnion -- transplantation,  Comparative Study,  Cryopreservation -- methods,  Female,  Human,  Male,  Middle Age,  Postoperative Complications,  Pterygium -- surgery,  Recurrence,  Safety,  Tissue Preservation -- methods,  Treatment Outcome

Author(s): Nalan Fatma Tekin,  Suleyman Kaynak,  Ali Osman Saatci,  Guray Cingil

Author Affiliation:

Nalan Fatma Tekin, MD; Suleyman Kaynak, MD; Ali Osman Saatci, MD; Guray Cingil, MD

From the Department of Ophthalmology, Dokuz Eylul University, Izmir, Turkey.

Accepted for publication April 9, 2001. Address reprint requests to Suleyman Kaynak, MD, Retina Goz Hastaliklari Arastirma ve Tedavi Merkezi, 1388 sok. No:16/A, 35220 Alsancak, Turkey [email: [email protected]].

Document Journal Article

305 PQ REVERSE_CHRON 1283785649

types:

Publication title:

Ophthalmic Surgery and Lasers. Thorofare: Nov/Dec 2001. Vol. 32, Iss. 6;  pg. 464, 6 pgs

Source type: Periodical

ISSN: 10823069

ProQuest document ID:

93903127

Text Word Count

2697

Document URL:

http://proquest.umi.com/pqdweb?did=93903127&sid=2&Fmt=4&clientId=98602&RQT=309&VName=PQD

Successful conjunctival grafts in pterygium depend on skillAnonymous. Ophthalmology Times. Cleveland: Apr 1, 1999. Vol. 24, Iss. 7; pg. 19, 1 pgs

Abstract (Summary)

Dr. [Tan] has also conducted a randomized clinical trial that compared bare sclera excisions with conjunctival autograft. "The recurrence rate in our population in Singapore for bare sclera excision for primary surgery was 61%," he said. "That went as high as 82% in recurrent cases. For conjunctival autografts, we had good results, with one recurrence (1.6%). This was, however, a one-surgeon trial."

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 (580  words)Copyright Advanstar Communications, Inc. Apr 1, 1999

SINGAPORE-A common problem with pterygium surgery is recurrence: Simple surgical excisions often result in a quick relapse.

However, the conjunctival autograft or autograft transplant has become the "gold standard" because it achieves the highest success rate of all modalities, according to Donald Tiang Hw Tan, MD, MBBS, an anterior segment surgeon in practice at the Singapore National Eye Centre.

Dr. Tan noted that there are benefits with the free conjunctival graft, in which conjunctiva from the bulbar area is placed over a bare sclera defect after excision.

"This is generally a very safe and effective procedure," he said. "Because it is technically demanding and surgeon-- dependent, recurrence rates differ widely, ranging from 2% to 35%."

Recurrence

Conjunctival grafts fail for a variety of reasons, noted Dr. Tan. "Recurrence can be caused by overly small grafts, with the pterygium appearing around the graft. Also, if the surgeon does not remove enough of the fibroblastic tissue, the pterygium will recur."

Severe retraction occurs if the graft is very thick. If the graft is not stable or not sutured in place, it will break down, retract, and cause a recurrence, said Dr. Tan. "We have seen several referral cases in which, surprisingly, a perfectly placed conjunctival autograft actually becomes a pterygium," he added.

Successful autografts

Lowering the recurrence rate in pterygium may be as simple as following a few essential rules, Dr. Tan said.

First, the surgeon should create a "large, generous graft ranging from 6 to 8 mm in diameter," he said. "Adequate removal of surrounding fibrovascular tissue is important, and it should be a thin Tenon's-free graft to prevent retraction.

"This means utilizing superficial dissection techniques, which can be quite difficult," he said. "Lastly, it should be a stable graft."

Dr. Tan has also conducted a randomized clinical trial that compared bare sclera excisions with conjunctival autograft. "The recurrence rate in our population in Singapore for bare sclera excision for primary surgery was 61%," he said. "That went as high as 82% in recurrent cases. For conjunctival autografts, we had good results, with one recurrence (1.6%). This was, however, a one-surgeon trial."

Modifications

There are limitations to conjunctival autografts, Dr. Tan cautioned, and he presented a few modifications of the procedure.

He termed the first modification a conjunctival rotational autograft. "This is a modification of the procedure in which the original epithelium overlying the pterygium can be used," he said. "It is dissected free and replaced over the bare sclera with a 1800 rotation."

The procedure is indicated when a conjunctival autograft cannot be performed: in patients with glaucoma, steroid responders, patients with pre-existing blebs, and patients with superior conjunctival scarring. Other indications are cases that require large grafts, particularly combined cataract and pterygium surgery.

Procedure

The area of epithelial excision is outlined, and the conjunctiva and epithelium nearest the head of pterygium are dissected carefully with superficial dissection techniques, Dr. Tan said.

Care is taken to avoid removing any of the underlying fibrovascular tissue. The epithelial graft is placed aside, while the underlying fibrovascular pterygium tissue is removed.

"Once a sterile bed is achieved, the epithelium is replaced, epithelial side up, but with a 1800 rotation," he said.

Another approach, the conjunctival rotational autograft, had a 4.5% recurrence rate in 51 consecutive cases, said Dr. Tan. A large rectangular autograft is obtained, then split to form an annular ring. The ring is wrapped around the limbus. This technique is particularly useful in large pterygia, he said.

[Photograph]Figure 1

Figure 2

Indexing (document details)

Subjects: Ophthalmology,  Eyes & eyesight,  Surgery,  Transplants & implants

People: Tan, Donald Tiang Hw

Author(s): Anonymous

Document types:

Feature

Publication title:

Ophthalmology Times. Cleveland: Apr 1, 1999. Vol. 24, Iss. 7;  pg. 19, 1 pgs

Source type: Periodical

ISSN: 0193032X

ProQuest document ID:

74811092

Text Word Count

580

Document URL:

http://proquest.umi.com/pqdweb?did=74811092&sid=2&Fmt=3&clientId=98602&RQT=309&VName=PQD

305 PQ REVERSE_CHRON 1283785751

Fibrin tissue adhesive has benefits in pterygium surgeryCheryl Guttman. Ophthalmology Times. Cleveland: Jul 15, 2005. Vol. 30, Iss. 14; pg. 12, 1 pgs

Abstract (Summary)

Dr. [John A. Hovanesian, MD] reported outcomes from 98 eyes evaluated in two retrospective studies of the use of the fibrin tissue adhesive. A first investigation compared surgery duration and postoperative comfort in 49 eyes of 39 patients that underwent surgery using fibrin tissue adhesive against 13 eyes of nine patients in which sutures were used.

 »  Jump to indexing (document details)

Full Text

 (905  words)Copyright Advanstar Communications, Inc. Jul 15, 2005

[Headnote]Viable alternative

[Headnote]Increased patient comfort, OR time savings help to offset cost of adhesive

Reviewed by John A. Hovanesian, MD

Washington, DC-Fibrin tissue adhesive (Tisseel VH Fibrin Sealant, Baxter BioSurgery) is a viable and attractive alternative to suturing in pterygium surgery with conjunctival-limbal autograft, said John A. Hovanesian, MD, at the World Cornea Congress V.

Dr. Hovanesian reported outcomes from 98 eyes evaluated in two retrospective studies of the use of the fibrin tissue adhesive. A first investigation compared surgery duration and postoperative comfort in 49 eyes of 39 patients that underwent surgery using fibrin tissue adhesive against 13 eyes of nine patients in which sutures were used. The second study included a larger cohort of 98 eyes of 95 patients followed for 6 to 12 months and was designed to assess graft survival and pterygium recurrence rate. Dr. Hovanesian performed all surgeries over a period of 1 year.

Enlarge 200%Enlarge 400%

[Photograph]Dr. Hovanesian

In the first study, statistically significant differences favored fibrin tissue adhesive over sutures for shorter operative time (13 versus 21 minutes, respectively) and for lessening pain after surgery. While patients in 38% of sutured cases rated their pain as moderate to severe, only 4% of cases performed with the fibrin adhesive were associated with that level of pain. In addition, the proportion of cases associated with no pain was nearly two-fold greater in the fibrin tissue adhesive group versus in the eyes with sutures, 41% versus 23%, respectively.

Graft survival

In the longer-term study, all grafts survived and there were no pterygium recurrences, defined as a >1-mm regrowth or need for reoperation. One graft developed a 1-mm diameter area of central necrosis. However, it spontaneously re-epithelialized within 2 weeks when managed with lubrication and topical treatment with a steroid and antibiotic and had done well at last follow-up at 6 months.

"Pterygium surgery is frequently combined with use of a conjunctival-limbal autograft because that technique is associated with a low rate of recurrence. Unfortunately, sutures used to fix the graft can cause significant postoperative inflammation," said Dr. Hovanesian, clinical instructor, Jules Stein Eye Institute, UCLA, Los Angeles.

"The fibrin tissue adhesive costs about $75 for one dose. However, its use seems to have no adverse impact on recurrence rate, and its benefits of OR time savings and increased patient comfort offset its higher cost relative to sutures," he added.

Attention to technique

Dr. Hovanesian's technique for the surgery begins with a standard excision of the pterygium from the cornea and conjunctiva, taking no more than a 1-mm margin of normal conjunctiva. Then, a thin conjunctival autograft is taken from the superior limbus

region using careful dissection to ensure an adequate complement of limbal stem cells is harvested while leaving Tenon's fascia in place as much as possible.

"This technique ensures a good cosmetic result in the graft and causes minimal scarring of the superior conjunctiva so that it is preserved if glaucoma surgery becomes necessary in the future," Dr. Hovanesian said.

Enlarge 200%Enlarge 400%

Figure 1 The superior limbal conjunctival autograft is dissected free from Tenon's fascia, and dissection is performed into the clear cornea to obtain limbal stem cells (blue line).Figure 2 Once freed from the limbus, the autograft includes stem cells.Figure 3 A drop of thrombin solution and a drop of fibrinogen sealant are placed on the scieral bed and the conjunctiva! autograft, respectively. (Figures courtesy of John A. Hovanesian, MD)

The harvested graft is inverted to lay epithelium against corneal epithelium, cut free with Vannas scissors, and moved in a limbus-to-limbus configuration near the bare sciera site.

The two components of the fibrin tissue adhesive are mixed on the eye in three steps by:

* placing a drop of the watery thrombin solution on the dry, bare sciera;

* placing a sparing amount (less than 1 drop) of the more viscous sealer protein solution (fibrinogen/aprotinin) on the stromal side of the conjunctival autograft; and

* inverting the graft onto the sciera using forceps.

The graft is then positioned, keeping its limbal edge aligned with the corneoscleral junction, and smoothed using forceps to achieve good edge alignment.

"The surgeon has only 10 to 15 seconds to position the graft appropriately before the mixture congeals, so it is important to move quickly," Dr. Hovanesian said.

The fibrin tissue adhesive secures the graft well for 7 to 10 days, which allows adequate time for healing. Postoperative care consists of overnight patching over ointment with

four-times-daily administration of prednisolone acetate 1% and a fluoroquinolone antibiotic.

Fibrin glue was first developed for use in neurologic, cardiac, and abdominal surgery. Its use in ophthalmic surgery is off-label, although there is a growing list of publications reporting its value in various applications, noted Dr. Hovanesian.

Although the components of the fibrin tissue adhesive are derived from pooled human and bovine blood, it has been used internationally for more than 25 years in approximately 8 million surgeries with no documented cases of transmission of hepatitis B or C, HIV, bovine spongiform encephalopathy, or prion-mediated disease.

FYI

John A. Hovanesian, MD

Phone: 949/951-2020

Fax: 949/951-9244

E-mail:[email protected]

Dr. Hovanesian has no financial interest in Tisseel VH or Baxter Healthcare.

[Sidebar]Take-Home MessageA retrospective review of 98 eyes undergoing pterygium surgery with fibrin tissue adhesive (Tisseel VH Fibrin Sealant, Baxter BioSurgery) to secure a conjunctival-limbal autograft demonstrates the adhesive is a safe alternative to sutures. It compares favorably with respect to recurrence risk, and has advantages for minimizing surgical time and postoperative pain.

Indexing (document details)

Subjects: Ophthalmology,  Eyes & eyesight,  Medical research,  Surgery,  Skin & tissue grafts

Author(s): Cheryl Guttman

Document types:

Feature

Document features:

Photographs,  Illustrations

305 PQ REVERSE_CHRON 1283785838

Section: Cornea

Publication title:

Ophthalmology Times. Cleveland: Jul 15, 2005. Vol. 30, Iss. 14;  pg. 12, 1 pgs

Source type: Periodical

ISSN: 0193032X

ProQuest document ID:

901162061

Text Word Count

905

Document URL:

http://proquest.umi.com/pqdweb?did=901162061&sid=2&Fmt=4&clientId=98602&RQT=309&VName=PQD