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A Periosteal-Temporalis Fascia Pedicle Flap for Repairing Impending Ocular Perforations and Extruding Keratoprostheses
A Periosteal-Temporalis Fascia Pedicle Flap for Repairing Impending Ocular Perforations and Extruding Keratoprostheses Thomas C. Spoor, M.D., John M. Ramocki, M.D., and John W. Cowden, M.D. We repaired four eyes in four patients with impending perforation using a vascular periosteal-temporalis fascia pedicle flap continuous to the periorbita of the orbital wall. Two eyes with extruding keratoprostheses, one eye with severe ocular surface dysfunction and a perforated, infected keratoplasty, and one eye with scleral ectasia were successfully reconstructed. Excellent visual acuity (20/25) was attained in one eye and functional visual acuity (20/100) was maintained in another. Structural integrity was maintained in all eyes. A vascularized flap was an excellent source of tissue for reconstructing eyes with impending perforation and scleral melting. MANY TISSUES have been used to treat actual or impending corneal and scleral perforations. Autogenous tissue, including mucous membrane, auricular cartilage, eyebank sclera, periosteum, fascia lata, and dermal fat grafts have been used with limited success. Lack of vascularity limits their success on avascular surfaces. Conjunctival flaps are vascular but often lack sufficient tensile strength to prevent perforation. We repaired four eyes successfully with a vascular periosteal-temporalis fascia pedicle flap continuous to the periorbita of the lateral orbital wall.
Material and Methods Periosteal-temporalis fascia advancement flaps were used to repair four eyes from four Accepted for publication Aug. 8, 1989. From the Kresge Eye Institute, the Department of Ophthalmology, Wayne State University School of Medicine, Detroit, Michigan. Reprint requests to Thomas C. Spoor, M.D., Kresge Eye Institute of Wayne State University, 3994 John R, Detroit, MI 48201.
704
patients over the past two and one half years. Patients were referred to the oculoplastic service for treatment after they underwent several unsuccessful reparative procedures. Two patients had extruding keratoprostheses; one patient had scleral ectasia, hypotony, and an extruding scleral buckle; a fourth patient had an ulcerated perforated keratoplasty secondary to a severe ocular surface disorder. All eyes progressed to impending or actual perforation. All patients underwent lateral orbitotomy with a periosteal-ternporalis flap created to cover the keratoprostheses or site of scleral ectasia or melting. All of these patients have done well since the periosteal flap was used to treat their impending perforation (Table). Follow-up ranged from between six and 34 months. The operation is performed under general anesthesia. The lateral canthal area, lateral orbital rim, and temporalis fossa are injected with a local anesthetic mixture of 5 ml of 2% lidocaine with 1:200,000 epinephrine hydrochloride, and 5 ml of 0.75% bupivacaine with 1:200,000 epinephrine hydrochloride combined with hyaluronidase. This anesthetic enhances hemostasis and provides postoperative analgesia. A Berke orbitotomy incision is made with a No. 15 Bard-Parker blade. The incision is made adjacent to the lateral canthus and continued to an area over the temporalis muscle to the tragus of the ear (Fig. 1). The lateral canthus may be preserved. Skin muscle flaps are elevated on either side of the incision. A rectangular flap of periosteal tissue approximately 20 mm wide and up to 75 mm in length is incised with a No. 15 Bard-Parker blade extended over the ternporalis fascia (Fig. 2), and the flap is then freed from the lateral orbital wall and temporalis muscle. The periosteum is elevated from the lateral orbital bone using a Freer periosteal elevator (Fig. 3). This dissection of periosteum from the lateral orbital bone is continued to the lateral orbital rim and mobilized carefully to preserve the flap's vascular supply from the
©AMERICAN JOURNAL OF OPHTHALMOLOGY
108:704-708,
DECEMBER,
1989
Keratoprosthesis Repair
Vol. 108, No.6
705
TABLE CLINICAL CHARACTERISTICS OF PATIENTS REQUIRING PERIOSTEAL-TEMPORALIS FASCIA FLAPS
PATIENT NO" AGE (YRS). SEX
FOLLOW-UP DIAGNOSIS
1,30, M
Alkali burns in both eyes
2, 14, F
Stevens-Johnson syndrome
3,40. M
Alkali bums in both eyes
4.73. M
Eroded scleral buckle, scleral ectasia
(MOS)
INITIAL VISUAL ACUITY
FINALVISUAL ACUITY'
34
L.P.
20/25
6
L.P.
L.P.
15
L.P.
L.P.
20/100
20/100
7
COMMENT
Requires trephination over keratoprosthesis optic every two months Dehisced. melted. and infected keratoplasty; refused evisceration; restored integrity of globe Eroded keratoprosthesis; refused enucleation Restored integrity of globe
* L.P. indicates light perception.
junctiva and episclera with additional interrupted 7-0 polyglactin sutures. The lateral canthus is reconstructed if it was not previously lysed. The deep layer of the lateral orbitotomy incision is closed with buried 4-0 polyglactin sutures, and the skin closed with a running, subcuticular 6-0 nylon suture (Fig. 5). The flap overlying the keratoprosthesis is excised, exposing the optic (Figs. 6 and 7).
zygomaticotemporal branch of the lacrimal artery supplying the lateral periorbita (Fig. 4). The lateral canthus mayor may not be incised at the surgeon's discretion. If it is not incised, a tunnel is created beneath the lateral canthus. The entire flap is then thinned with Westcott scissors, especially along its temporal aspect. The bulbar conjunctiva surrounding the keratoprosthesis or ectatic sclera is undermined. The periosteal-temporalis fascia flap is brought through the lateral canthus and tunneled beneath the bulbar conjunctiva (Fig. 4). The distal end of the flap is sewn over the keratoprosthesis with 7-0 interrupted polyglactin sutures sewn to the medial aspect of bulbar and tarsal conjunctiva. The remaining edges of the flap are sewn to the edges of the bulbar con-
Case 1 A 21-year-old man suffered bilateral ocular alkali burns from caustic soda when cleaning a
Fig. 1 (Spoor, Ramocki, and Cowden). Lateral Berke-type incision for creating a periosteal-ternporalis fascia flap.
Fig. 2 (Spoor, Ramocki, and Cowden). Periostealtemporalis fascia flap outlined after completing a lateral orbital dissection.
Case Reports
706
AMERICAN JOURNAL OF OPHTHALMOLOGY
December, 1989
Fig. 3 (Spoor, Ramocki, and Cowden). Periosteal-temporalis fascia flap dissected free from lateral orbital tissue. drain in November 1984. Although he received immediate irrigation to both eyes, he subsequently required three penetrating keratoplasties; failure necessitated a keratoprosthesis on the left eye in October 1985. A scleral patch with a conjunctival flap was used to revise the keratoprosthesis because of scleral melting on the nasal side of the Girard keratoprosthesis one month later. By September 1986, the temporal sclera over the flange of the keratoprosthesis became exposed (Fig. 8). Continued melting of the sclera in this area necessitated a lateral orbitotomy with mobilization of periosteal-temporalis fascia flap over the keratoprosthesis in October 1986. A small buttonhole was excised over the site of the keratoprosthesis. Corrected visual acuity was 20/25 one week after surgery. The patient is now able to drive his truck and hunt deer with the aid of the keratoprosthesis in his one sighted eye. The
eye requires trephination of excessive tissue from the keratoprosthesis optic every six to eight weeks (Fig. 7). Case 2 A 14-year-old girl with severe ocular surface dysfunction secondary to Stevens-Johnson syndrome underwent two keratoplasties that failed in the left eye. After the second keratoplasty, a corneal ulcer and a fungal endophthalmitis developed. Vigorous treatment with vitrectomy, intravitreal amphotericin, and a penetrating keratoplasty salvaged the eye. Useful vision was lost. The keratoplasty melted, and the wound dehisced. The patient refused evisceration. Subsequently, the globe was reconstructed with a periosteal-temporalis fascia flap placed over the melting corneal graft. The structural integrity of the eye has been maintained for the past eight months.
Fig. 4 (Spoor, Ramocki, and Cowden). Periosteal-temporalis fascia flap placed through the tunnel in the lateral canthal area and placed over the keratoprosthesis. Note that flap is hinged at the lateral orbital wall and that it is an extension of the lateral periorbita.
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707
Fig. 5 (Spoor, Ramocki, and Cowden). Periostealtemporalis flap covering keratoprosthesis. Lateral canthus has been reconstructed.
Fig. 6 (Spoor, Ramocki, and Cowden). Periostealtemporalis fascia flap in position covering keratoprosthesis with window created centrally. The lateral orbital incision site is now fully closed.
Case 3 A 40-year-old man suffered severe alkali burns to both eyes in 1977. He underwent multiple operations on both eyes and had multiple failed keratoplasties. A Girard keratoprosthesis was placed in the right eye in April 1985. Thinning of the sclera and conjunctiva became noticeable by March 1986. The patient underwent a revision of the keratoprosthesis with the placement of an additional scleral graft in April 1986. In May 1986, subsequent revision of the keratoprosthesis with a new scleral onlay graft was accomplished. A conjunctival flap was also placed over the prosthesis at the time because of a large nasal area of exposed protoplast of the prosthesis. By April 1988, a few areas of erosion were beginning to occur through the conjunctival flap. The mesh
of the nasal side of the keratoprosthesis was exposed. A lateral orbitotomy was performed, and a periosteal-temporalis fascia flap was placed over the right eye. The patient has done well and has retained his keratoprosthesis in his right eye for 15 months. Case 4 A 73-year-old man had decreased vision in his left eye. He had undergone an intracapsular cataract extraction and scleral buckling procedure several years before examination. Examination disclosed a vitreous hemorrhage with some chorioretinal cryopexy scars posterior to an anterior encircling buckle. An area of scleral ectasia was present adjacent to a suture at the 2 o'clock meridian, just posterior to the muscle insertion.
Fig. 7 (Spoor, Ramocki, and Cowden). Keratoprosthesis secured by a periosteal-temporalis fascia flap. Visual acuity has been 20/25 for past 30 months.
Fig. 8 (Spoor, Ramocki, and Cowden). Nearperforation from extruding keratoprosthesis with erosion of protoplast through temporal sclera.
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December, 1989
AMERICAN JOURNAL OF OPHTHALMOLOGY
The patient was examined at intervals, and the vitreous hemorrhage resolved. He returned five months later with clear media and a bestcorrected visual acuity of 201100. No cause could be found for the vitreous hemorrhage other than the area of scleral ectasia. On Dec. 2, 1988, the patient underwent a lateral orbitotomy, and a periosteal-temporalis fascia flap was created to protect the impending perforation of the left globe. To date, the patient has maintained vision and has retained anatomic integrity of his eye. No further erosion of the sclera or extrusion of the buckle has occurred.
Discussion Erosion around a keratoprosthesis and extrusion of the prosthesis are the major complications of keratoprosthetic surgery. 1.2 Placement of a keratoprosthesis is often the last resort in attempting to restore vision. The placement of protective conjunctival flaps and scleral grafts and the revision of keratoprostheses are frequently necessary in patients with keratoprostheses because erosion and extrusion occur in many of these patients." The most common complication of keratoprosthesis implantation is melting of the tissue around the optical core, with leakage of ocular contents and extrusion of the implant. Both eyes with keratoprostheses had undergone various procedures to prevent this melting and extrusion process. We have also used a periosteal-temporalis fascia flap to repair scleral ectasia with impending perforation and necrotizing ocular perforations. Such vascular, viable tissue is an excellent source for repairing necrotizing, avascular cornea or sclera. It does not necrose or melt and makes an excellent patch graft. Many tissues have been and continue to be used in the repair of perforations caused by necrotizing scleritis and keratitis. Drawbacks of various tissue patches include undue thickness of the material and lack of durability caused by either necrosis or deficient tensile strength. Exposure of the patched material or an inadequate vascular supply can hasten necrosis, as can recognition by the host tissue of a nonautogenous patch graft as foreign. We believe the use of a periosteal-temporalis flap is superior to any alternate tissue in this type of repair. Autogenous fascia lata, free periosteal grafts, cartilage, homologous sclera, and split-thickness dermal grafts all have their
advocates. All of these alternate tissues have been used as scleral or corneal patch grafts with limited success. Necrosis of autogenous fascia lata, split-thickness grafts, periosteum, and cartilage can occur from exposure and an insufficient vascular supply. An adequate blood supply to the graft reduces the likelihood of graft resorption and necrosis. The periosteal-temporalis flap is supple and does not form a bulky, irregular surface. The flap retains a good vascular supply and is brought through a tunnel underneath the lateral canthus and bulbar conjunctiva. It is viable and covers the area of defect well. The flap is easily covered with conjunctiva or mucous membrane. It has excellent tensile strength and is flexible and cosmetically pleasing. Because this periosteal-temporalis flap is autogenous, there is no risk of rejection. The base of the pedicle flap is hinged upon the lateral orbital wall (Fig. 4). Its blood supply is derived from the zygomaticotemporal branch of the lacrimal artery. The lacrimal artery may be derived from both the meningeal and the ophthalmic arteries." Such vascular, viable tissue is an excellent source for repair of necrotizing avascular cornea or sclera. Because it is vascular, this flap does not necrose, and it makes an excellent patch graft. However, this luxuriant growth of tissue may obscure the optic of a keratoprosthesis, requiring trephination every six to eight weeks (Case 1). We used a periosteal-temporalis flap to repair four eyes with impending perforation successfully. One patient is able to see well enough to drive and hunt. We recommend this periostealtemporalis flap to protect and cover eyes with impending perforation. The technique is simple and can be performed by an oculoplastic surgeon or orbital surgeon. The periostealtemporalis flap has been so successful that we recently used it as a primary procedure in the placement of keratoprostheses in one patient.
References 1. Barber, J. c.: Keratoprosthesis. Past and present. Int. Ophthalmol. Gin. 28:103, 1988. 2. Aquavella, J. V., Rao, G. N., Brown, A. c.. and Harris, J. K.: Keratoprosthesis. Results, complications, and management. Ophthalmology 89:655, 1982. 3. Zide, B. M., and Jelks, G. W.: Surgical Anatomy of the Orbit. New York, Raven Press, 1985, pp. 13-19.
Material and Methods Periosteal-temporalis fascia advancement flaps were used to repair four eyes from four Accepted for publication Aug. 8, 1989. From the Kresge Eye Institute, the Department of Ophthalmology, Wayne State University School of Medicine, Detroit, Michigan. Reprint requests to Thomas C. Spoor, M.D., Kresge Eye Institute of Wayne State University, 3994 John R, Detroit, MI 48201.
704
patients over the past two and one half years. Patients were referred to the oculoplastic service for treatment after they underwent several unsuccessful reparative procedures. Two patients had extruding keratoprostheses; one patient had scleral ectasia, hypotony, and an extruding scleral buckle; a fourth patient had an ulcerated perforated keratoplasty secondary to a severe ocular surface disorder. All eyes progressed to impending or actual perforation. All patients underwent lateral orbitotomy with a periosteal-ternporalis flap created to cover the keratoprostheses or site of scleral ectasia or melting. All of these patients have done well since the periosteal flap was used to treat their impending perforation (Table). Follow-up ranged from between six and 34 months. The operation is performed under general anesthesia. The lateral canthal area, lateral orbital rim, and temporalis fossa are injected with a local anesthetic mixture of 5 ml of 2% lidocaine with 1:200,000 epinephrine hydrochloride, and 5 ml of 0.75% bupivacaine with 1:200,000 epinephrine hydrochloride combined with hyaluronidase. This anesthetic enhances hemostasis and provides postoperative analgesia. A Berke orbitotomy incision is made with a No. 15 Bard-Parker blade. The incision is made adjacent to the lateral canthus and continued to an area over the temporalis muscle to the tragus of the ear (Fig. 1). The lateral canthus may be preserved. Skin muscle flaps are elevated on either side of the incision. A rectangular flap of periosteal tissue approximately 20 mm wide and up to 75 mm in length is incised with a No. 15 Bard-Parker blade extended over the ternporalis fascia (Fig. 2), and the flap is then freed from the lateral orbital wall and temporalis muscle. The periosteum is elevated from the lateral orbital bone using a Freer periosteal elevator (Fig. 3). This dissection of periosteum from the lateral orbital bone is continued to the lateral orbital rim and mobilized carefully to preserve the flap's vascular supply from the
©AMERICAN JOURNAL OF OPHTHALMOLOGY
108:704-708,
DECEMBER,
1989
Keratoprosthesis Repair
Vol. 108, No.6
705
TABLE CLINICAL CHARACTERISTICS OF PATIENTS REQUIRING PERIOSTEAL-TEMPORALIS FASCIA FLAPS
PATIENT NO" AGE (YRS). SEX
FOLLOW-UP DIAGNOSIS
1,30, M
Alkali burns in both eyes
2, 14, F
Stevens-Johnson syndrome
3,40. M
Alkali bums in both eyes
4.73. M
Eroded scleral buckle, scleral ectasia
(MOS)
INITIAL VISUAL ACUITY
FINALVISUAL ACUITY'
34
L.P.
20/25
6
L.P.
L.P.
15
L.P.
L.P.
20/100
20/100
7
COMMENT
Requires trephination over keratoprosthesis optic every two months Dehisced. melted. and infected keratoplasty; refused evisceration; restored integrity of globe Eroded keratoprosthesis; refused enucleation Restored integrity of globe
* L.P. indicates light perception.
junctiva and episclera with additional interrupted 7-0 polyglactin sutures. The lateral canthus is reconstructed if it was not previously lysed. The deep layer of the lateral orbitotomy incision is closed with buried 4-0 polyglactin sutures, and the skin closed with a running, subcuticular 6-0 nylon suture (Fig. 5). The flap overlying the keratoprosthesis is excised, exposing the optic (Figs. 6 and 7).
zygomaticotemporal branch of the lacrimal artery supplying the lateral periorbita (Fig. 4). The lateral canthus mayor may not be incised at the surgeon's discretion. If it is not incised, a tunnel is created beneath the lateral canthus. The entire flap is then thinned with Westcott scissors, especially along its temporal aspect. The bulbar conjunctiva surrounding the keratoprosthesis or ectatic sclera is undermined. The periosteal-temporalis fascia flap is brought through the lateral canthus and tunneled beneath the bulbar conjunctiva (Fig. 4). The distal end of the flap is sewn over the keratoprosthesis with 7-0 interrupted polyglactin sutures sewn to the medial aspect of bulbar and tarsal conjunctiva. The remaining edges of the flap are sewn to the edges of the bulbar con-
Case 1 A 21-year-old man suffered bilateral ocular alkali burns from caustic soda when cleaning a
Fig. 1 (Spoor, Ramocki, and Cowden). Lateral Berke-type incision for creating a periosteal-ternporalis fascia flap.
Fig. 2 (Spoor, Ramocki, and Cowden). Periostealtemporalis fascia flap outlined after completing a lateral orbital dissection.
Case Reports
706
AMERICAN JOURNAL OF OPHTHALMOLOGY
December, 1989
Fig. 3 (Spoor, Ramocki, and Cowden). Periosteal-temporalis fascia flap dissected free from lateral orbital tissue. drain in November 1984. Although he received immediate irrigation to both eyes, he subsequently required three penetrating keratoplasties; failure necessitated a keratoprosthesis on the left eye in October 1985. A scleral patch with a conjunctival flap was used to revise the keratoprosthesis because of scleral melting on the nasal side of the Girard keratoprosthesis one month later. By September 1986, the temporal sclera over the flange of the keratoprosthesis became exposed (Fig. 8). Continued melting of the sclera in this area necessitated a lateral orbitotomy with mobilization of periosteal-temporalis fascia flap over the keratoprosthesis in October 1986. A small buttonhole was excised over the site of the keratoprosthesis. Corrected visual acuity was 20/25 one week after surgery. The patient is now able to drive his truck and hunt deer with the aid of the keratoprosthesis in his one sighted eye. The
eye requires trephination of excessive tissue from the keratoprosthesis optic every six to eight weeks (Fig. 7). Case 2 A 14-year-old girl with severe ocular surface dysfunction secondary to Stevens-Johnson syndrome underwent two keratoplasties that failed in the left eye. After the second keratoplasty, a corneal ulcer and a fungal endophthalmitis developed. Vigorous treatment with vitrectomy, intravitreal amphotericin, and a penetrating keratoplasty salvaged the eye. Useful vision was lost. The keratoplasty melted, and the wound dehisced. The patient refused evisceration. Subsequently, the globe was reconstructed with a periosteal-temporalis fascia flap placed over the melting corneal graft. The structural integrity of the eye has been maintained for the past eight months.
Fig. 4 (Spoor, Ramocki, and Cowden). Periosteal-temporalis fascia flap placed through the tunnel in the lateral canthal area and placed over the keratoprosthesis. Note that flap is hinged at the lateral orbital wall and that it is an extension of the lateral periorbita.
Vol. 108, No.6
Keratoprosthesis Repair
707
Fig. 5 (Spoor, Ramocki, and Cowden). Periostealtemporalis flap covering keratoprosthesis. Lateral canthus has been reconstructed.
Fig. 6 (Spoor, Ramocki, and Cowden). Periostealtemporalis fascia flap in position covering keratoprosthesis with window created centrally. The lateral orbital incision site is now fully closed.
Case 3 A 40-year-old man suffered severe alkali burns to both eyes in 1977. He underwent multiple operations on both eyes and had multiple failed keratoplasties. A Girard keratoprosthesis was placed in the right eye in April 1985. Thinning of the sclera and conjunctiva became noticeable by March 1986. The patient underwent a revision of the keratoprosthesis with the placement of an additional scleral graft in April 1986. In May 1986, subsequent revision of the keratoprosthesis with a new scleral onlay graft was accomplished. A conjunctival flap was also placed over the prosthesis at the time because of a large nasal area of exposed protoplast of the prosthesis. By April 1988, a few areas of erosion were beginning to occur through the conjunctival flap. The mesh
of the nasal side of the keratoprosthesis was exposed. A lateral orbitotomy was performed, and a periosteal-temporalis fascia flap was placed over the right eye. The patient has done well and has retained his keratoprosthesis in his right eye for 15 months. Case 4 A 73-year-old man had decreased vision in his left eye. He had undergone an intracapsular cataract extraction and scleral buckling procedure several years before examination. Examination disclosed a vitreous hemorrhage with some chorioretinal cryopexy scars posterior to an anterior encircling buckle. An area of scleral ectasia was present adjacent to a suture at the 2 o'clock meridian, just posterior to the muscle insertion.
Fig. 7 (Spoor, Ramocki, and Cowden). Keratoprosthesis secured by a periosteal-temporalis fascia flap. Visual acuity has been 20/25 for past 30 months.
Fig. 8 (Spoor, Ramocki, and Cowden). Nearperforation from extruding keratoprosthesis with erosion of protoplast through temporal sclera.
708
December, 1989
AMERICAN JOURNAL OF OPHTHALMOLOGY
The patient was examined at intervals, and the vitreous hemorrhage resolved. He returned five months later with clear media and a bestcorrected visual acuity of 201100. No cause could be found for the vitreous hemorrhage other than the area of scleral ectasia. On Dec. 2, 1988, the patient underwent a lateral orbitotomy, and a periosteal-temporalis fascia flap was created to protect the impending perforation of the left globe. To date, the patient has maintained vision and has retained anatomic integrity of his eye. No further erosion of the sclera or extrusion of the buckle has occurred.
Discussion Erosion around a keratoprosthesis and extrusion of the prosthesis are the major complications of keratoprosthetic surgery. 1.2 Placement of a keratoprosthesis is often the last resort in attempting to restore vision. The placement of protective conjunctival flaps and scleral grafts and the revision of keratoprostheses are frequently necessary in patients with keratoprostheses because erosion and extrusion occur in many of these patients." The most common complication of keratoprosthesis implantation is melting of the tissue around the optical core, with leakage of ocular contents and extrusion of the implant. Both eyes with keratoprostheses had undergone various procedures to prevent this melting and extrusion process. We have also used a periosteal-temporalis fascia flap to repair scleral ectasia with impending perforation and necrotizing ocular perforations. Such vascular, viable tissue is an excellent source for repairing necrotizing, avascular cornea or sclera. It does not necrose or melt and makes an excellent patch graft. Many tissues have been and continue to be used in the repair of perforations caused by necrotizing scleritis and keratitis. Drawbacks of various tissue patches include undue thickness of the material and lack of durability caused by either necrosis or deficient tensile strength. Exposure of the patched material or an inadequate vascular supply can hasten necrosis, as can recognition by the host tissue of a nonautogenous patch graft as foreign. We believe the use of a periosteal-temporalis flap is superior to any alternate tissue in this type of repair. Autogenous fascia lata, free periosteal grafts, cartilage, homologous sclera, and split-thickness dermal grafts all have their
advocates. All of these alternate tissues have been used as scleral or corneal patch grafts with limited success. Necrosis of autogenous fascia lata, split-thickness grafts, periosteum, and cartilage can occur from exposure and an insufficient vascular supply. An adequate blood supply to the graft reduces the likelihood of graft resorption and necrosis. The periosteal-temporalis flap is supple and does not form a bulky, irregular surface. The flap retains a good vascular supply and is brought through a tunnel underneath the lateral canthus and bulbar conjunctiva. It is viable and covers the area of defect well. The flap is easily covered with conjunctiva or mucous membrane. It has excellent tensile strength and is flexible and cosmetically pleasing. Because this periosteal-temporalis flap is autogenous, there is no risk of rejection. The base of the pedicle flap is hinged upon the lateral orbital wall (Fig. 4). Its blood supply is derived from the zygomaticotemporal branch of the lacrimal artery. The lacrimal artery may be derived from both the meningeal and the ophthalmic arteries." Such vascular, viable tissue is an excellent source for repair of necrotizing avascular cornea or sclera. Because it is vascular, this flap does not necrose, and it makes an excellent patch graft. However, this luxuriant growth of tissue may obscure the optic of a keratoprosthesis, requiring trephination every six to eight weeks (Case 1). We used a periosteal-temporalis flap to repair four eyes with impending perforation successfully. One patient is able to see well enough to drive and hunt. We recommend this periostealtemporalis flap to protect and cover eyes with impending perforation. The technique is simple and can be performed by an oculoplastic surgeon or orbital surgeon. The periostealtemporalis flap has been so successful that we recently used it as a primary procedure in the placement of keratoprostheses in one patient.
References 1. Barber, J. c.: Keratoprosthesis. Past and present. Int. Ophthalmol. Gin. 28:103, 1988. 2. Aquavella, J. V., Rao, G. N., Brown, A. c.. and Harris, J. K.: Keratoprosthesis. Results, complications, and management. Ophthalmology 89:655, 1982. 3. Zide, B. M., and Jelks, G. W.: Surgical Anatomy of the Orbit. New York, Raven Press, 1985, pp. 13-19.