CASE REPORT
Retained Host Descemet Membrane (Auto-DMET) During Conversion of Deep Anterior Lamellar Keratoplasty to Penetrating Keratoplasty: A Case Report Lucas M. M. Vianna, MD,*†‡ Fasika Woreta, MD,* Amanda E. Kiely, MD,* and Albert S. Jun, MD, PhD*
Purpose: The aim of this study was to relate a case of deep anterior lamellar keratoplasty (DALK) converted to penetrating keratoplasty in which the host central Descemet membrane (DM) with a large perforation was left attached to the host cornea.
Methods: This is a case report of a 34-year-old man who underwent an attempted DALK for keratoconus in his left eye, which became complicated with a large rupture in DM during dissection. The host DM was left in place, the donor cornea with DM intact was sutured onto the host bed, and air was injected into the anterior chamber. The patient was monitored by biomicroscopy, pachymetry, topography, anterior segment optical coherence tomography, and specular microscopy. Results: The postoperative course resulted in improved uncorrected visual acuity, best spectacle-corrected visual acuity, and topography. Corneal edema was observed in the host cornea peripheral to the graft. Three months after the surgery, the endothelial cell density was reduced by 63% compared with the preoperative donor cell density. Conclusions: Leaving the host DM during conversion of DALK to penetrating keratoplasty was uneventful in this case, although corneal edema was observed in the area overlying the host cornea. It is possible that the retained DM could provide additional autologous endothelial cells to prolong graft survival. Key Words: cornea, keratoconus, penetrating keratoplasty, deep anterior lamellar keratoplasty, Descemet membrane (Cornea 2014;33:865–867)
D
eep anterior lamellar keratoplasty (DALK) has important advantages over penetrating keratoplasty (PK) and is a good surgical option for corneal diseases not involving
Received for publication April 9, 2014; revision received April 16, 2014; accepted April 17, 2014. Published online ahead of print June 9, 2014. From the *Department of Ophthalmology, Cornea and Anterior Segment Service, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD; †Department of Ophthalmology, Federal University of São Paulo/ Paulista School of Medicine, São Paulo, Brazil; and ‡Department of Ophthalmology, State University of Rio de Janeiro, Rio de Janeiro, Brazil. The authors have no funding or conflicts of interest to disclose. Reprints: Albert S. Jun, MD, PhD, 400 N. Broadway, Smith Building 5011, Baltimore, MD 21231 (e-mail: [email protected]). Copyright © 2014 by Lippincott Williams & Wilkins
Cornea Volume 33, Number 8, August 2014
the endothelium.1–3 Optimal surgical and visual outcomes depend on maximal baring of Descemet membrane (DM), which can lead to its perforation, the most common intraoperative complication.1–3 Few studies have evaluated the prognosis of DM perforation during DALK.4,5 In cases of small perforations, the procedure can be completed with air injections into the anterior chamber. In large perforations, converting to PK after removing the host DM is the standard procedure because of the possibility of a double anterior chamber and stromal opacity formation.4,5 Concerning endothelial pathologies, Descemet stripping (automated) endothelial keratoplasty6 and Descemet membrane endothelial keratoplasty7 are also increasing in popularity. Recently, some cases of complete endothelial cell repopulation and corneal clearance despite subtotal8,9 and total (tentatively named “Descemet membrane endothelial transfer”—DMET)10,11 graft detachment were reported. We report a case of DALK converted to penetrating keratoplasty (PK) in which the host central DM with a large perforation was left attached to the host cornea. We suggest the possibility that the host DM can function as an “auto-DMET” and potentially improve long-term graft survival of the PK in these patients.
CASE REPORT A 34-year-old black man presented with the diagnosis of keratoconus and progressive blurred vision in both eyes and an apical corneal scar in his left eye in July 2013. The corrected distance visual acuity with spectacles was 20/125 oculus dexter and 20/150 oculus sinister, with a manifest refraction of 26.50 +6.00 · 45 in the right eye and +0.50 +6.00 · 180 in the left eye. Bilaterally, slit-lamp examination showed papillae on the tarsal conjunctiva and central corneal scar with a positive Munson sign, Fleischer ring, Vogt striae, and inferior steepening with an iron ring, worse in the left eye. Fundus examination was unremarkable in both eyes. On Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany), the apical thickness was found to be 408 mm in the left eye. Because of the severity of keratoconus, the patient was unable to wear a contact lens. After discussing treatment options, risks, benefits, and alternatives, the patient elected to undergo a DALK. The Anwar technique12 was performed with the successful formation of a big bubble. During the final steps of posterior stromal dissection, a large tear occurred in the DM, and extended superiorly to the angle. The visual axis was clear. The host DM was not excised and was left attached to the host cornea by a superiortemporal pedicle. A viscoelastic was placed on the iris, and the donor cornea with intact DM was sutured onto the host bed with 16 www.corneajrnl.com |
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Vianna et al
FIGURE 1. Anterior biomicroscopy showing normal corneal transparency except in the superotemporal area (left panel arrows) overlying the host DM that can be seen rolled up in the superotemporal angle on anterior segment optical coherence tomography (right panel arrows). interrupted 10-0 nylon sutures. The viscoelastic was aspirated from the anterior chamber near the end of the case. Air was injected into the anterior chamber, leaving an air bubble of a diameter similar to that of the graft, and the patient was instructed to lie flat for 50 minutes in the postoperative area and instructed to maintain this position for at least 10 minutes every hour during the first week. Standard postoperative topical antibiotic was given four times daily and topical 1% prednisolone acetate was given initially as 1 drop every 2 hours, while the patient was awake, during the first week. The antibiotics were discontinued after 1 week, and corticosteroids were tapered to once a day over 6 weeks. The postoperative course showed improvement in the uncorrected visual acuity and best spectacle-corrected visual acuity, to achieve 20/40 after 3 months. Biomicroscopy showed normal corneal transparency except in the superior-temporal area overlying the host detached DM that could be seen rolled up in the temporal superior angle on anterior segment optical coherence tomography (Fig. 1). The endothelial cell density (ECD) was 1138 cells per square millimeter in the third month postoperatively. The donor cornea had an ECD of 3067 cells per square millimeter.
DISCUSSION While performing DALK in which a large rupture in the DM occurs, the most common response according to the literature is to convert to PK, by removing the free host DM.4,5 We report a case of an attempted DALK with a large rupture in which the host DM attached only by a pedicle was left in the anterior chamber in addition to converting to PK (tentatively named auto-DMET). It is known that the host DM with its endothelium in an uneventful DALK has better endothelium outcomes when compared with those of PK. Because the hypothesis that a free donor DM left in the anterior chamber secondary to a detached Descemet membrane endothelial keratoplasty could play a role in endothelial recovery as described in the literature,10 could a torn and detached host DM during attempted DALK, or even a piece of it, have any positive or negative contribution to the endothelium postoperatively? In our case, the postoperative course was as usual for a PK, with the visual acuity reaching 20/40 after 3 months. Normal recovery of corneal transparency was observed,
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although corneal edema was present in the area overlying the host DM remnant from the central cornea (Fig. 1). The donor cornea had an ECD of 3067 cells per square millimeter measured at the time of preservation and was used after 5 days. By 3 months postoperatively, the ECD was 1138 cells per square millimeter. The rate of endothelial cell loss after PK is reported to be about 16% to 29% within the first 6 months.13–16 Our case has apparently a higher initial loss rate than is related in the literature, although this could have been because of perioperative factors, such as intraoperative trauma. If the lower ECD at 3 months in our case was because of surgical trauma to the graft endothelium, the retained host DM could have either positive or negative effects on the ECD in the graft in the long term. Over time, it could contribute to the ECD to offset the normally observed natural attrition of endothelial cells in post-PK corneas1 or after insults such as graft rejection episodes. In this case, the retained DM would act as a reservoir of host endothelial cells, and act as an autoDMET. Alternatively, it could theoretically reduce the ECD, possibly by mechanical contact between the donor and recipient tissue. Although this scenario has undoubtedly been faced by many surgeons who perform DALK, some of whom may have not excised the ruptured DM before converting to PK, the present case is the first to our knowledge to describe such an occurrence and its outcome. A longer term follow-up of ECD in our patient and possibly in others treated in a similar manner could provide insights into the effects of the retained DM in aborted DALK surgery. If the outcomes are shown to be positive, such an approach could become a more widespread component of managing this surgical occurrence.
REFERENCES 1. Reinhart WJ, Musch DC, Jacobs DS, et al. Deep anterior lamellar keratoplasty as an alternative to penetrating keratoplasty a report by the American Academy of Ophthalmology. Ophthalmology. 2011;118: 209–218. 2. Rama P, Knutsson KA, Razzoli G, et al. Deep anterior lamellar keratoplasty using an original manual technique. Br J Ophthalmol. 2013;97:23–27.
2014 Lippincott Williams & Wilkins
Cornea Volume 33, Number 8, August 2014
3. Smadja D, Colin J, Krueger RR, et al. Outcomes of deep anterior lamellar keratoplasty for keratoconus: learning curve and advantages of the big bubble technique. Cornea. 2012;31:859–863. 4. Den S, Shimmura S, Tsubota K, et al. Impact of the Descemet membrane perforation on surgical outcomes after deep lamellar keratoplasty. Am J Ophthalmol. 2007;143:750–754. 5. Leccisotti A. Descemet’s membrane perforation during deep anterior lamellar keratoplasty: prognosis. J Cataract Refract Surg. 2007;33:825–829. 6. Lee WB, Jacobs DS, Musch DC, et al. Descemet’s stripping endothelial keratoplasty: safety and outcomes: a report by the American Academy of Ophthalmology. Ophthalmology. 2009;116:1818–1830. 7. Dapena I, Ham L, Melles GR. Endothelial keratoplasty: DSEK/DSAEK or DMEK—the thinner the better? Curr Opin Ophthalmol. 2009;20:299–307. 8. Balachandran C, Ham L, Verschoor CA, et al. Spontaneous corneal clearance despite graft detachment in Descemet membrane endothelial keratoplasty (DMEK). Am J Ophthalmol. 2009;148:227–234. 9. Price FW Jr, Price MO. Spontaneous corneal clearance despite graft detachment after Descemet membrane endothelial keratoplasty. Am J Ophthalmol. 2010;149:173–174; author reply 174–175.
2014 Lippincott Williams & Wilkins
Retained Host DM During DALK to PK Conversion
10. Dirisamer M, Ham L, Dapena I, et al. Descemet membrane endothelial transfer (DMET) “Free floating” donor Descemet implantation as a potential alternative to “keratoplasty.” Cornea. 2012;31:194–197. 11. Dirisamer M, Yeh RY, van Dijk K, et al. Recipient endothelium may relate to corneal clearance in Descemet membrane endothelial transfer. Am J Ophthalmol. 2012;154:290–296. 12. Anwar M, Teichmann KD. Big-bubble technique to bare Descemet’s membrane in anterior lamellar keratoplasty. J Cataract Refract Surg. 2002;28:398–403. 13. Bourne WM. Cellular changes in transplanted human corneas: Castroviejo lecture. Cornea. 2001;20:560–569. 14. Nishimura JK, Hodge DO, Bourne WM. Initial endothelial cell density and chronic endothelial cell loss rate in corneal transplants with late endothelial failure. Ophthalmology. 1999;106:1962–1965. 15. Alqudah AA, Terry MA, Straiko MD, et al. Immediate endothelial cell loss after penetrating keratoplasty. Cornea. 2013;32:1587– 1590. 16. Bertelmann E, Pleyer U, Rieck P. Risk factors for endothelial cell loss post-keratoplasty. Acta Ophthalmol Scand. 2006;84:766–770.
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Retained Host Descemet Membrane (Auto-DMET) During Conversion of Deep Anterior Lamellar Keratoplasty to Penetrating Keratoplasty: A Case Report Lucas M. M. Vianna, MD,*†‡ Fasika Woreta, MD,* Amanda E. Kiely, MD,* and Albert S. Jun, MD, PhD*
Purpose: The aim of this study was to relate a case of deep anterior lamellar keratoplasty (DALK) converted to penetrating keratoplasty in which the host central Descemet membrane (DM) with a large perforation was left attached to the host cornea.
Methods: This is a case report of a 34-year-old man who underwent an attempted DALK for keratoconus in his left eye, which became complicated with a large rupture in DM during dissection. The host DM was left in place, the donor cornea with DM intact was sutured onto the host bed, and air was injected into the anterior chamber. The patient was monitored by biomicroscopy, pachymetry, topography, anterior segment optical coherence tomography, and specular microscopy. Results: The postoperative course resulted in improved uncorrected visual acuity, best spectacle-corrected visual acuity, and topography. Corneal edema was observed in the host cornea peripheral to the graft. Three months after the surgery, the endothelial cell density was reduced by 63% compared with the preoperative donor cell density. Conclusions: Leaving the host DM during conversion of DALK to penetrating keratoplasty was uneventful in this case, although corneal edema was observed in the area overlying the host cornea. It is possible that the retained DM could provide additional autologous endothelial cells to prolong graft survival. Key Words: cornea, keratoconus, penetrating keratoplasty, deep anterior lamellar keratoplasty, Descemet membrane (Cornea 2014;33:865–867)
D
eep anterior lamellar keratoplasty (DALK) has important advantages over penetrating keratoplasty (PK) and is a good surgical option for corneal diseases not involving
Received for publication April 9, 2014; revision received April 16, 2014; accepted April 17, 2014. Published online ahead of print June 9, 2014. From the *Department of Ophthalmology, Cornea and Anterior Segment Service, Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD; †Department of Ophthalmology, Federal University of São Paulo/ Paulista School of Medicine, São Paulo, Brazil; and ‡Department of Ophthalmology, State University of Rio de Janeiro, Rio de Janeiro, Brazil. The authors have no funding or conflicts of interest to disclose. Reprints: Albert S. Jun, MD, PhD, 400 N. Broadway, Smith Building 5011, Baltimore, MD 21231 (e-mail: [email protected]). Copyright © 2014 by Lippincott Williams & Wilkins
Cornea Volume 33, Number 8, August 2014
the endothelium.1–3 Optimal surgical and visual outcomes depend on maximal baring of Descemet membrane (DM), which can lead to its perforation, the most common intraoperative complication.1–3 Few studies have evaluated the prognosis of DM perforation during DALK.4,5 In cases of small perforations, the procedure can be completed with air injections into the anterior chamber. In large perforations, converting to PK after removing the host DM is the standard procedure because of the possibility of a double anterior chamber and stromal opacity formation.4,5 Concerning endothelial pathologies, Descemet stripping (automated) endothelial keratoplasty6 and Descemet membrane endothelial keratoplasty7 are also increasing in popularity. Recently, some cases of complete endothelial cell repopulation and corneal clearance despite subtotal8,9 and total (tentatively named “Descemet membrane endothelial transfer”—DMET)10,11 graft detachment were reported. We report a case of DALK converted to penetrating keratoplasty (PK) in which the host central DM with a large perforation was left attached to the host cornea. We suggest the possibility that the host DM can function as an “auto-DMET” and potentially improve long-term graft survival of the PK in these patients.
CASE REPORT A 34-year-old black man presented with the diagnosis of keratoconus and progressive blurred vision in both eyes and an apical corneal scar in his left eye in July 2013. The corrected distance visual acuity with spectacles was 20/125 oculus dexter and 20/150 oculus sinister, with a manifest refraction of 26.50 +6.00 · 45 in the right eye and +0.50 +6.00 · 180 in the left eye. Bilaterally, slit-lamp examination showed papillae on the tarsal conjunctiva and central corneal scar with a positive Munson sign, Fleischer ring, Vogt striae, and inferior steepening with an iron ring, worse in the left eye. Fundus examination was unremarkable in both eyes. On Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany), the apical thickness was found to be 408 mm in the left eye. Because of the severity of keratoconus, the patient was unable to wear a contact lens. After discussing treatment options, risks, benefits, and alternatives, the patient elected to undergo a DALK. The Anwar technique12 was performed with the successful formation of a big bubble. During the final steps of posterior stromal dissection, a large tear occurred in the DM, and extended superiorly to the angle. The visual axis was clear. The host DM was not excised and was left attached to the host cornea by a superiortemporal pedicle. A viscoelastic was placed on the iris, and the donor cornea with intact DM was sutured onto the host bed with 16 www.corneajrnl.com |
865
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Vianna et al
FIGURE 1. Anterior biomicroscopy showing normal corneal transparency except in the superotemporal area (left panel arrows) overlying the host DM that can be seen rolled up in the superotemporal angle on anterior segment optical coherence tomography (right panel arrows). interrupted 10-0 nylon sutures. The viscoelastic was aspirated from the anterior chamber near the end of the case. Air was injected into the anterior chamber, leaving an air bubble of a diameter similar to that of the graft, and the patient was instructed to lie flat for 50 minutes in the postoperative area and instructed to maintain this position for at least 10 minutes every hour during the first week. Standard postoperative topical antibiotic was given four times daily and topical 1% prednisolone acetate was given initially as 1 drop every 2 hours, while the patient was awake, during the first week. The antibiotics were discontinued after 1 week, and corticosteroids were tapered to once a day over 6 weeks. The postoperative course showed improvement in the uncorrected visual acuity and best spectacle-corrected visual acuity, to achieve 20/40 after 3 months. Biomicroscopy showed normal corneal transparency except in the superior-temporal area overlying the host detached DM that could be seen rolled up in the temporal superior angle on anterior segment optical coherence tomography (Fig. 1). The endothelial cell density (ECD) was 1138 cells per square millimeter in the third month postoperatively. The donor cornea had an ECD of 3067 cells per square millimeter.
DISCUSSION While performing DALK in which a large rupture in the DM occurs, the most common response according to the literature is to convert to PK, by removing the free host DM.4,5 We report a case of an attempted DALK with a large rupture in which the host DM attached only by a pedicle was left in the anterior chamber in addition to converting to PK (tentatively named auto-DMET). It is known that the host DM with its endothelium in an uneventful DALK has better endothelium outcomes when compared with those of PK. Because the hypothesis that a free donor DM left in the anterior chamber secondary to a detached Descemet membrane endothelial keratoplasty could play a role in endothelial recovery as described in the literature,10 could a torn and detached host DM during attempted DALK, or even a piece of it, have any positive or negative contribution to the endothelium postoperatively? In our case, the postoperative course was as usual for a PK, with the visual acuity reaching 20/40 after 3 months. Normal recovery of corneal transparency was observed,
866
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although corneal edema was present in the area overlying the host DM remnant from the central cornea (Fig. 1). The donor cornea had an ECD of 3067 cells per square millimeter measured at the time of preservation and was used after 5 days. By 3 months postoperatively, the ECD was 1138 cells per square millimeter. The rate of endothelial cell loss after PK is reported to be about 16% to 29% within the first 6 months.13–16 Our case has apparently a higher initial loss rate than is related in the literature, although this could have been because of perioperative factors, such as intraoperative trauma. If the lower ECD at 3 months in our case was because of surgical trauma to the graft endothelium, the retained host DM could have either positive or negative effects on the ECD in the graft in the long term. Over time, it could contribute to the ECD to offset the normally observed natural attrition of endothelial cells in post-PK corneas1 or after insults such as graft rejection episodes. In this case, the retained DM would act as a reservoir of host endothelial cells, and act as an autoDMET. Alternatively, it could theoretically reduce the ECD, possibly by mechanical contact between the donor and recipient tissue. Although this scenario has undoubtedly been faced by many surgeons who perform DALK, some of whom may have not excised the ruptured DM before converting to PK, the present case is the first to our knowledge to describe such an occurrence and its outcome. A longer term follow-up of ECD in our patient and possibly in others treated in a similar manner could provide insights into the effects of the retained DM in aborted DALK surgery. If the outcomes are shown to be positive, such an approach could become a more widespread component of managing this surgical occurrence.
REFERENCES 1. Reinhart WJ, Musch DC, Jacobs DS, et al. Deep anterior lamellar keratoplasty as an alternative to penetrating keratoplasty a report by the American Academy of Ophthalmology. Ophthalmology. 2011;118: 209–218. 2. Rama P, Knutsson KA, Razzoli G, et al. Deep anterior lamellar keratoplasty using an original manual technique. Br J Ophthalmol. 2013;97:23–27.
2014 Lippincott Williams & Wilkins
Cornea Volume 33, Number 8, August 2014
3. Smadja D, Colin J, Krueger RR, et al. Outcomes of deep anterior lamellar keratoplasty for keratoconus: learning curve and advantages of the big bubble technique. Cornea. 2012;31:859–863. 4. Den S, Shimmura S, Tsubota K, et al. Impact of the Descemet membrane perforation on surgical outcomes after deep lamellar keratoplasty. Am J Ophthalmol. 2007;143:750–754. 5. Leccisotti A. Descemet’s membrane perforation during deep anterior lamellar keratoplasty: prognosis. J Cataract Refract Surg. 2007;33:825–829. 6. Lee WB, Jacobs DS, Musch DC, et al. Descemet’s stripping endothelial keratoplasty: safety and outcomes: a report by the American Academy of Ophthalmology. Ophthalmology. 2009;116:1818–1830. 7. Dapena I, Ham L, Melles GR. Endothelial keratoplasty: DSEK/DSAEK or DMEK—the thinner the better? Curr Opin Ophthalmol. 2009;20:299–307. 8. Balachandran C, Ham L, Verschoor CA, et al. Spontaneous corneal clearance despite graft detachment in Descemet membrane endothelial keratoplasty (DMEK). Am J Ophthalmol. 2009;148:227–234. 9. Price FW Jr, Price MO. Spontaneous corneal clearance despite graft detachment after Descemet membrane endothelial keratoplasty. Am J Ophthalmol. 2010;149:173–174; author reply 174–175.
2014 Lippincott Williams & Wilkins
Retained Host DM During DALK to PK Conversion
10. Dirisamer M, Ham L, Dapena I, et al. Descemet membrane endothelial transfer (DMET) “Free floating” donor Descemet implantation as a potential alternative to “keratoplasty.” Cornea. 2012;31:194–197. 11. Dirisamer M, Yeh RY, van Dijk K, et al. Recipient endothelium may relate to corneal clearance in Descemet membrane endothelial transfer. Am J Ophthalmol. 2012;154:290–296. 12. Anwar M, Teichmann KD. Big-bubble technique to bare Descemet’s membrane in anterior lamellar keratoplasty. J Cataract Refract Surg. 2002;28:398–403. 13. Bourne WM. Cellular changes in transplanted human corneas: Castroviejo lecture. Cornea. 2001;20:560–569. 14. Nishimura JK, Hodge DO, Bourne WM. Initial endothelial cell density and chronic endothelial cell loss rate in corneal transplants with late endothelial failure. Ophthalmology. 1999;106:1962–1965. 15. Alqudah AA, Terry MA, Straiko MD, et al. Immediate endothelial cell loss after penetrating keratoplasty. Cornea. 2013;32:1587– 1590. 16. Bertelmann E, Pleyer U, Rieck P. Risk factors for endothelial cell loss post-keratoplasty. Acta Ophthalmol Scand. 2006;84:766–770.
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