Acute hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus.

We report a case of acute corneal hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus. A healthy 24-year-old female patient underwent Dresden protocol cross-linking in her left eye due to advanced keratoconus. After five years of a stable cornea, she returned with epiphora, blurred vision, and a soft left eye. Acute hydrops and corneal perforation were diagnosed. There was no history of pregnancy, atopy, eye rubbing, trauma, or contact lens use. Local antibiotic and eye patching were applied. Three months after the resolution of the acute episode, she retained useful visual acuity with no need for further surgery. Although cross-linking efficiently halts keratoconus, progression can occur, leading to corneal hydrops and perforation, even in the absence of any risk factors.

Acute hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus / Hidropisia aguda seguida de perfuração da córnea cinco anos após reticulação corneana para ceratocone

ABSTRACT We report a case of acute corneal hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus. A healthy 24-year-old female patient underwent Dresden protocol cross-linking in her left eye due to advanced keratoconus. After five years of a stable cornea, she returned with epiphora, blurred vision, and a soft left eye. Acute hydrops and corneal perforation were diagnosed. There was no history of pregnancy, atopy, eye rubbing, trauma, or contact lens use. Local antibiotic and eye patching were applied. Three months after the resolution of the acute episode, she retained useful visual acuity with no need for further surgery. Although cross-linking efficiently halts keratoconus, progression can occur, leading to corneal hydrops and perforation, even in the absence of any risk factors.

RESUMO Este é o relato de um caso de hidropisia aguda seguida de perfuração corneana cinco anos após reticulação corneana para ceratocone. Uma paciente saudável de 24 anos foi submetida a reticulação corneana no olho esquerdo pelo protocolo de Dresden, devido a um ceratocone avançado. Após cinco anos com a córnea estável, a paciente retornou com epífora, visão turva e amolecimento do olho esquerdo. Foram diagnosticadas hidropisia aguda e perfuração corneana. A paciente não tinha história de gravidez, atopia, fricção ocular, trauma ou uso de lentes de contato. Foram aplicados um antibiótico local e um tampão oftalmológico. Três meses após a resolução do episódio agudo, ela manteve uma acuidade visual útil, sem necessidade de novas cirurgias. Embora a reticulação interrompa de forma eficiente o ceratocone, pode ocorrer progressão, levando a hidropisia e perfuração da córnea, mesmo na ausência de fatores de risco.

Correction to: Visual, refractive and topographic outcomes of progressive thickness intrastromal corneal ring segments for keratoconic eyes.

In the original publication, the Results paragraph of the abstract was published incorrectly. The correct version should read as follows.

Visual, refractive and topographic outcomes of progressive thickness intrastromal corneal ring segments for keratoconic eyes.

PURPOSE: To evaluate one-year visual, refractive, and topographic outcomes of 58 eyes of 53 keratoconus patients who underwent surgery with a progressive thickness intrastromal corneal ring segment (ICRS). METHODS: This multi-center, retrospective, observational study evaluates the one-year effects of progressive thickness ICRS implanted in keratoconus patients meeting the inclusion criteria. One or two progressive ICRS were implanted in the selected eyes after creating an intrastromal tunnel with a femtosecond laser. Pre- and postoperative uncorrected distance visual acuity, best-corrected distance visual acuity, manifest refraction (both spherical equivalent and cylindrical refractions), corneal astigmatism, maximum keratometry, corneal thickness, and corneal topography measurements and indices were evaluated. RESULTS: In this retrospective case series, 58 eyes of 53 keratoconus patients were included with a follow-up of 12 months. The mean age was 30.89 ± 11.90 years. There were improvements postoperatively in mean values of visual acuities, both uncorrected from 0.71 (preoperatively) to 0.28 (log MAR), and best-corrected from 0.28 to 0.10 (log MAR), mean cylindrical refraction from - 2.35 ± 1.51 to - 4.15 ± 2.23 D, and mean spherical equivalent from - 2.10 ± 2.25 to - 4.64 ± 3.2 D. There was also a reduction in maximal keratometry from 54.21 D preoperatively to 50.93 D postoperatively. CONCLUSION: The implantation of the progressive thickness ICRS is an effective and safe method to improve the vision of keratoconic eyes. Corneal stability was maintained at the 12-month mark.

Treatment of perforated cornea with an autologous lamellar scleral graft: histologic findings.

We report a case of central corneal perforation treated with an autologous lamellar scleral graft and histologic findings obtained after a subsequent penetrating keratoplasty. A corneal perforation within a large Pseudomonas ulcer in a 55-year-old male rigid gas permeable contact lens wearer was sealed by a lamellar scleral graft from the same eye, followed by an uneventful penetrating keratoplasty 6 months later. Histology of the excised button revealed that the well-apposed graft, which maintained the irregular arrangement of the scleral collagen fibers, was embedded in the corneal stroma over the deep blood vessels and a rupture in Descemet's membrane. The clinical and histologic findings showed that autologous lamellar scleral grafts can be successfully used for the emergency treatment of corneal perforation when a corneal transplant is not available. The distinctive scleral structure revealed by histology and the inadequate graft transparency indicate that visual rehabilitation of eyes with a central corneal perforation can be achieved only by a subsequent optic penetrating keratoplasty.

Treatment of perforated cornea with an autologous lamellar scleral graft: histologic findings / Tratamento de córnea perfurada com enxerto autônomo de esclera lamelar: achados histológicos

ABSTRACT We report a case of central corneal perforation treated with an autologous lamellar scleral graft and histologic findings obtained after a subsequent penetrating keratoplasty. A corneal perforation within a large Pseudomonas ulcer in a 55-year-old male rigid gas permeable contact lens wearer was sealed by a lamellar scleral graft from the same eye, followed by an uneventful penetrating keratoplasty 6 months later. Histology of the excised button revealed that the well-apposed graft, which maintained the irregular arrangement of the scleral collagen fibers, was embedded in the corneal stroma over the deep blood vessels and a rupture in Descemet's membrane. The clinical and histologic findings showed that autologous lamellar scleral grafts can be successfully used for the emergency treatment of corneal perforation when a corneal transplant is not available. The distinctive scleral structure revealed by histology and the inadequate graft transparency indicate that visual rehabilitation of eyes with a central corneal perforation can be achieved only by a subsequent optic penetrating keratoplasty.

RESUMO Relatamos um caso de perfuração corneana central tratada com enxerto autólogo lamelar de esclera e os achados histológicos obtidos após ceratoplastia penetrante (CP) subsequente. Uma perfuração da córnea devido a uma grande úlcera por Pseudomonas em um usuário de lentes de contato rígidas gás permeável de 55 anos de idade foi selada por um enxerto escleral lamelar do mesmo olho, seguida de ceratoplastia penetrante, sem intercorrências, seis meses depois. A histologia do botão excisado revelou que um enxerto bem posicionado, que manteve o arranjo irregular das fibras de colágeno escleral, foi incorporado no estroma corneano sobre os vasos sanguíneos profundos e uma ruptura na membrana de Descemet. Os achados clínicos e histológicos demonstraram que o enxerto autônomo de esclerose lamelar pode ser usado com sucesso como tratamento de emergência da perfuração da córnea, quando o transplante de córnea não é possível. A estrutura escleral característica revelada pela histologia e a transparência inadequada do enxerto indicam que a reabilitação visual dos olhos com uma perfuração corneana central só pode ser alcançada através de uma ceratoplastia penetrante óptica subsequente.

Intraocular Pressure Measurements Referring to the Corneal Thickness in Keratoconic Eyes After Corneal Crosslinking with Riboflavin and Ultraviolet A.

AIM: To determine the possible relation between intraocular pressure (IOP), central corneal thickness (CCT) and corneal resistance (CR) in kerotoconic eyes before, 3,6 and 12 months after collagen crosslinking procedure (CXL) with aim to find out does the thicker cornea means already more resistance cornea followed with higher IOP. METHODS: Thirty eyes (30 patients) with central keratoconus (KC)were evaluated in retrospective cross sectional study. The corneal biomechanical parameters were taken with Wave Light Allegro Oculyzer produced by Alcon before the CXL, 3, 6 and 12 months after the procedure. IOP were checked by Goldmann applanation tonometry (GAT) before, 3, 6 and 12 months after CXL. RESULTS: The value of IOP before the CXL was 12,0 mmHg (10,62-15,25 mmHg), 3 months later 13,5 mmHg (11,0-16,0 mmHg), 6 months 14,0 mmHg (11,0-16,0 mmHg) and 12 months later 15,0 mmHg (10,37-17,25 mmHg) and was statistically significant higher (p=0,015) comparing to the value of IOP 3 months after the CXL, IOP 12 months after CXL procedure was statistically significant higher comparing to preoperative values (p=0,010). There were no statistically significant difference between the values 3 and 6 months after CXL. The CCT before the CXL procedure was 449 (433-505,75 microns), 3 months after CXL was 420 (383-473microns, p < 0,005), 6 months later 437 (401,25-480,25, p=0,001), 12 months after CXL 437 (401-503 microns, p=0,001). However there is statistically significant difference in CCT 12 months after CXL 437 (401-503microns p=0,032) and the value of CCT 3 months later the procedure (p=0,004) and the CCT 12 months after CXL and the value of CXL 6 months after CXL (p=0,036). The value of CCT did not show any statistically significant difference 3 and 6 months postoperatively. CONCLUSION: After riboflavin-UVA CXL in eyes with KC there was significant decrease in central corneal thickness 3 and 6 months after the procedure and the thickness is almost the same 12 months later. However IOP is low before CXL, raising up 3 and 6 months after CXL but significant increase is seen 12 months later. It means the regular measurement of IOP could be the serious and confident indicator of increasing of corneal resistance which is the main goal of CXL treatment.

Assessment of the tomographic values in keratoconic eyes after collagen crosslinking procedure.

GOAL: This study aimed to investigate the differences in values of K1 and K2 readings, the central corneal thickness (PAH) before the collagen crosslinking procedure (CXL) and 3, 6, 12 months later. METHODS: 64 eyes were evaluated in retrospective cross sectional study. The corneal biomechanical parameters were taken with WaveLight Allegro Oculyzer produced by Alcon before the CXL, 3,6, 12 months after the procedure. The curvature of K1 reading and K2 reading were taken and the central corneal thickness were considered due to the time after CXL. RESULTS: The value of K1 reading before the treatment was 48.8 diopters (D) (46.65-50.50) and was statistically significant lower comparing to the value of K1 3 months after the collagen CXL procedure 46.30 D (43.57-49.45) (p=0.0006), K1 reading one year post collagen CXL procedure was 47.20 D (44.35-50.07) (p=0.002). The value of K2 reading before the collagen CXL procedure was 52.65 D (47.55-54.72), 3 months after the procedure was 51.4 (45.05-54.0), 6 months later 48.55 D (47.20-50.62), 12 months later 51.30 D (47.22-54.77). There is statistically significant lower value of K2 reading 6 months after the treatment comparing to the values 3 months postoperatively (p=0.014). However there is significantly lower values of K2 reading 12 months postoperatively comparing to preoperative period (p=0.006). The value of central corneal thickness preoperative was 431.0 microns (398.0-446.25), 3 months after collagen CXL procedure was 373.50 microns (363.25-430.75), 6 months later 435.0 microns (360.0-464.75), 12 months after the CXL procedure was 429.50 microns (357.75-496.25). There is statistically significant lower values of central corneal thickness 3 months after collagen CXL treatment comparing to the central corneal thickness preoperative (p<0.005). There is statistically significant lower values of pachymetry 12 months after the CXL procedure comparing to the values 6 months later (p=0.036) and those preoperativelly (p=0.032). There is no statistically significant difference in the values of central corneal thickness in the period from 3 and 6 months postoperatively. CONCLUSION: After riboflavin-UVA CXL in eyes with keratokonus there was significant decrease in central corneal thickness 3 and 6 months after the procedure and the thickness is almost the same 12 months. However, K2 (Kmax) reading is significantly changed 3 and 6 months later and is followed by changing of K1 reading.

Predictive Values of Optical Coherence Tomography (OCT) Parameters in Assessment of Glaucoma progression.

GOAL: the purpose of the current study was to estimate the predictive values of optical coherence tomography parameters in early, developed perimetric and terminal glaucoma. METHODS: 180 eyes of 120 consecutive patients were evaluated in this retrospective cross sectional pilot study. Copernicus Spectral -domain optical coherence tomography with resolution of 3 mm obtained throught the optic nerve head were included. All examined eyes were divided to four groups (healthy,early, developed perimetric glaucoma and terminal glaucoma). The values of the thicknes of the retinal nerve fibre layer, the size of the disk, the volume of the cup, the E/D parameter and the size of the RIM were compared in four study groups. RESULTS: The sensitivity of RNFL was 90,0%, specificity 82,0 %, positive predictability 83,3 % and negative predictability was 89,1 %. The total accuracy was 86,0 % and area under curve (AUC) was 0,878 for RNFL indeks compering early to developed glaucoma. The sensitivity for CUP was 78%, the specificity was 80,8 %, the positive predictability 81,2% and the negative predictability was 77,5 %. The total accuracy was 79,3 % and area under curve (AUC) was 0,86 compering early to developed glaucoma. The sensitivity for E/D was 82,0%, the specificity was 82,9 % the positive predictability 83,7 % and the negative predictability was 81,3 %. The total accuracy was 82,5 % and area under curve (AUC) for E/D was 0,89 compering eearly to developed glaucoma. The sensitivity for RIM was 78,0%, the specificity was 76,6 %, the positive predictability was 84,7 and the negative predictability was 67,7 %. The total accuracy was 77,5 % and area under curve (AUC) for the RIM compering the developed to terminal glaucoma was 0,792. The sensitivity of RNFL was 88,0 %, the specificity was 66,7 %, the positive predictability was 81,5% and the negative predictability was 76,9%. The total accuracy was 80,0% and the area under curve (AUC) for RNFL compering developed to terminal glaucoma was 0,815. The incrreasing 0,1 unit RNFL decreases the risk of developing glaucoma from early to another developed stage of glaucoma for 6,95%. The increasing of E/D for only one unit increases the risk to develop another stage of glaucoma for 18,75 times. The increasing of RNFL for only one unit decreases the risk of performing developed glaucoma from initial stage for 7,8%. The increasing for only one unit of CUP increases the risk to develop terminal glaucoma for 8,47 times and increasing for 0,1 unit of the value of RIM decreases the risk developing terminal glaucoma for 9,27%. The increasing for 0,01 unit of the E/D index increases the risk for terminal glaucoma for 23,23 times. The increasing for one unit of RNFL decreasing the risk developing terminal glaucoma for 5,7%.

Correlation between retinal nerve fiber layer and disc parameters in glaucoma suspected eyes.

GOAL: The aim of the study was to estimate the diagnostic accuracy of optical coherence tomography parameters in normal, preperimetric, developed perimetric and terminal glaucoma. METHODS: 180 eyes of 140 consecutive patients were evaluated in this retrospective cross sectional pilot study. Copernicus Spectra--domain optical coherence tomography with resolution of 3 mm obtained through the optic nerve head were included. All examined eyes were divided into four groups (healthy eyes, initial, preperimetric glaucoma, developed perimetric glaucoma and terminal glaucoma). RESULTS: The highest value of the RIM is noticed in control group 1.44 (1.21-1.70). There is no significant difference in the size of the disc in the eyes with developed open angle glaucoma (1.80 +/- 0.66) compared to normal eyes (p = 0.663), to the eyes with initial glaucoma (p = 0.120), and terminal glaucomatous atrophy (p = 0.068). There is statistically importance of E/D parameter in healthy group 0.17 (0.04-0.27), early glaucomatous group 0.44 (0.35-0.51), developed glaucoma 0.47 (0.39-0.61) respectively p < 0.005. The volume of cup was significantly greater in the eyes with terminal glaucomatous atrophy 1.05 (0.85-1.4) compared to the healthy eyes 0.31 (0.06-0.51) (p < 0.005), significantly greater to initial glaucoma 0.84 (0.58-1.12) (p = 0.007) and significantly higher compared to developed glaucoma 0.82 (0.62-1.07) (p = 0.003). There is no significant difference in the cup between the eyes with early and developed glaucoma (p = 0.912). The eyes with terminal glaucoma had significant lower value of the thickness of retinal nerve fiber layer 56.50 (45.50-71.25) compared to developed glaucoma group 82.5 (72-95.75), initial glaucoma 110.50 (102-123) and healthy eyes 132 (119-150) (p < 0.005). CONCLUSION: The SD-OCT scanning should be used to quantify optic nerve head anatomy in human eyes. The changes can be recognized and can indicate as important risk factor in considering glaucoma changes. It also should be considered as an exact model of glaucoma pathology.

Collagen copolymer toric phakic intraocular lens for residual myopic astigmatism after intrastromal corneal ring segment implantation and corneal collagen crosslinking in a 3-stage procedure for keratoconus.

PURPOSE: To evaluate staged combined treatment for keratoconus with intrastromal corneal ring segment (ICRS) implantation followed by corneal collagen crosslinking (CXL) with riboflavin-ultraviolet-A (UVA) and then toric implantable collagen copolymer phakic intraocular lens (pIOL) implantation. SETTING: Large private ophthalmic hospital system. DESIGN: Case series. METHODS: Eyes with progressive keratoconus had ICRS implantation, then CXL, and then pIOL implantation (minimum 6 months between procedures). RESULTS: The study enrolled 14 eyes (9 patients). After the combined treatments, the mean decimal uncorrected distance visual acuity (UDVA) and mean decimal corrected distance visual acuity (CDVA) were significantly improved from 0.01 and 0.14, respectively, preoperatively to 0.44 and 0.57, respectively (P<.0001). The mean manifest refraction spherical equivalent decreased from -16.40 diopters (D) ± 3.56 (SD) (range -11.50 to -22.50 D) to -0.80 ± 1.02 D (range -2.00 to +2.00 D) after the combined treatments (P<.0001). The mean refractive astigmatism decreased from -4.73 ± 1.32 D (range -3.00 to -7.00 D) to -0.96 ± 0.35 D (range -0.50 to -1.50 D) (P<.0001). The mean steep and mean flat keratometry values reduced from 60.57 D and 56.16 D, respectively, to 54.48 D and 53.57 D (P<.0001), respectively. No intraoperative or postoperative complications occurred. CONCLUSIONS: A combined 3-stage-approach keratoconus treatment comprising ICRS implantation followed by CXL and then toric pIOL implantation was effective in improving functional vision and reducing disease progression. Longer term studies are required for further evaluation and comparison with other methods.

Topography-guided transepithelial PRK after intracorneal ring segments implantation and corneal collagen CXL in a three-step procedure for keratoconus.

PURPOSE: To present the results of topography-guided transepithelial photorefractive keratectomy (PRK) after intracorneal ring segments implantation followed by corneal collagen cross-linking (CXL) for keratoconus. METHODS: In this prospective case series, 10 patients (16 eyes) with progressive keratoconus were included. All patients underwent topography-guided transepithelial PRK after Keraring intracorneal ring segments (Mediphacos Ltda) implantation, followed by CXL treatment. The follow-up period was 6 months after the last procedure for all patients. Time interval between both intracorneal ring segments implantation and CXL and between CXL and topography-guided transepithelial PRK was 6 months. RESULTS: LogMAR mean uncorrected distance visual acuity and mean corrected distance visual acuity were significantly improved (P<.05) from 1.14±0.36 and 0.75±0.24 preoperatively to 0.25±0.13 and 0.13±0.06 after the completion of the three-step procedure, respectively. Mean spherical equivalent refraction was significantly reduced (P<.05) from -5.66±5.63 diopters (D) preoperatively to -0.98±2.21 D after the three-step procedure. Mean steep and flat keratometry values were significantly reduced (P<.05) from 54.65±5.80 D and 47.80±3.97 D preoperatively to 45.99±3.12 D and 44.69±3.19 D after the three-step procedure, respectively. CONCLUSIONS: Combined topography-guided transepithelial PRK with intracorneal ring segments implantation and CXL in a three-step procedure seems to be an effective, promising treatment sequence offering patients a functional visual acuity and ceasing progression of the ectatic disorder. A longer follow-up and larger case series are necessary to thoroughly evaluate safety, stability, and efficacy of this innovative procedure.

The results of corneal cross-linking in the treatment of keratoconus.

GOAL: To estimate corneal cross-linking (CXL) in keratoconus not only as a treatment to heal and increase the corneal stability then to consider it as a refractive procedure. METHODS: 28 eyes of 22 patients with progressive keratokonus were enrolled in prospective comparative study. Average follow up was 9 +/- 2 months (range 5 to 12 months). RESULTS: 6 months later uncorrected visual acuity (UCVA) was 0,2 (range 0,1 -0,5) and was significant higher to UCVA one month after the operation but not different to the results of UCVA before the CXL and three months later. The visual acuity with spectacles or hard contact lenses (BCVA) 6 months after CXL was 0,8 (range 0,57 -1,0) and was extremely higher then before the intervention (p=0,003), one month after CXL (p= 0,001) and significantly higher three months later (p=0,011). CONCLUSION: the CXL shows evident reduction in spherical equivalent refraction, cylinder and max K.

IntraLase femtosecond laser vs mechanical microkeratomes in LASIK for myopia: a systematic review and meta-analysis.

PURPOSE: To evaluate the safety, efficacy, and predictability of IntraLase (Abbott Medical Optics) femtosecond laser-assisted compared to microkeratome-assisted myopic LASIK. METHODS: A comprehensive literature search of Cochrane Library, PubMed, and EMBASE was conducted to identify relevant trials comparing LASIK with IntraLase femtosecond laser to LASIK with microkeratomes for the correction of myopia. Meta-analyses were performed on the primary outcomes (loss of ≥2 lines of corrected distance visual acuity [CDVA], uncorrected distance visual acuity [UDVA] 20/20 or better, manifest refraction spherical equivalent [MRSE] within ±0.50 diopters [D], final refractive SE, and astigmatism), and secondary outcomes (flap thickness predictability, changes in higher order aberrations [HOAs], and complications). RESULTS: Fifteen articles describing a total of 3679 eyes were identified. No significant differences were identified between the two groups in regards to a loss of ≥2 lines of CDVA (P=.44), patients achieving UDVA 20/20 or better (P=.24), final UDVA (P=.12), final mean refractive SE (P=.74), final astigmatism (P=.27), or changes in HOAs. The IntraLase group had more patients who were within ±0.50 D of target refraction (P=.05) compared to the microkeratome group, and flap thickness was more predictable in the IntraLase group (P<.0001). The microkeratome group had more epithelial defects (P=.04), whereas the IntraLase group had more cases of diffuse lamellar keratitis (P=.01). CONCLUSIONS: According to the available data, LASIK with the IntraLase femtosecond laser offers no significant benefits over LASIK with microkeratomes in regards to safety and efficacy, but has potential advantages in predictability.

Femtosecond LASIK retreatment using side cutting only.

PURPOSE: To present visual and refractive outcomes in 11 eyes that underwent femtosecond LASIK and subsequent retreatment with flap lifting using only side cutting. METHODS: Seven patients (11 eyes) with a mean age of 30.55±5.42 years (range: 24 to 39 years) underwent retreatment 18.18±5.41 months (range: 12 to 26 months) after primary LASIK treatment with side cutting only using a femtosecond laser for the correction of residual refractive error. RESULTS: Mean follow-up after retreatment was 7.72±1.48 months (range: 6 to 10 months). No intra- or postoperative complications were found after LASIK retreatment. Uncorrected distance visual acuity (UDVA) improved in all patients. Mean UDVA improved from 0.54±0.12 (decimal scale) (range: 0.4 to 0.7) preoperatively to 0.99±0.03 (range: 0.9 to 1.0) after retreatment. No patient lost lines of corrected distance visual acuity. CONCLUSIONS: Retreatment using a femtosecond laser to create only a side cut is an effective modality to treat residual refractive errors in postoperative LASIK patients.

One cornea for two patients: case report.

Case reporting the use of one donor cornea for two transplantation procedures: deep anterior lamellar keratoplasty (DALK) in a case of an imminent corneal perforation caused by herpetic stromal necrosis, and Descemet stripping with endothelial keratoplasty (DSEK) in an eye with pseudophakic bullous keratopathy (PBK). Descemet's membrane (DM), denuded by stromal necrosis, served as the starting point for dissection plane and creation of the recipient bed for DALK. The next steps were excision of the diseased stroma along the edge of trephination, and transplantation of a 400-450 microm thick, manually dissected lamellar graft. The remaining posterior layers of the donor cornea, 100-150 microm thick, were used as a graft in the DSEK procedure for PBK. The integrity of the globe was saved, and best-corrected visual acuity (BCVA) of 20/40 was reached after DALK in the eye with an imminent corneal perforation. A subnormal central corneal thickness (CCT) of 430 microm did not interfere with corneal shape (43.50 x 45.50 D) and function. The graft remained attached and clear after DSEK in the eye with PBK, with BCVA of 20/30 and a CCT of 653 microm. One donor cornea can be used for two lamellar keratoplasties, DALK and DSEK. Although the described obstacles may prevent this approach from becoming widely used, it may prove useful when one is confronted with a need for an urgent anterior lamellar keratoplasty, a long list of cases for DSEK, and a shortage of donor corneas.

One cornea for two patients: case report / Uma córnea para dois pacientes: relato de caso

Case reporting the use of one donor cornea for two transplantation procedures: deep anterior lamellar keratoplasty (DALK) in a case of an imminent corneal perforation caused by herpetic stromal necrosis, and Descemet stripping with endothelial keratoplasty (DSEK) in an eye with pseudophakic bullous keratopathy (PBK). Descemet's membrane (DM), denuded by stromal necrosis, served as the starting point for dissection plane and creation of the recipient bed for DALK. The next steps were excision of the diseased stroma along the edge of trephination, and transplantation of a 400-450 µm thick, manually dissected lamellar graft. The remaining posterior layers of the donor cornea, 100-150 µm thick, were used as a graft in the DSEK procedure for PBK. The integrity of the globe was saved, and best-corrected visual acuity (BCVA) of 20/40 was reached after DALK in the eye with an imminent corneal perforation. A subnormal central corneal thickness (CCT) of 430 µm did not interfere with corneal shape (43.50 x 45.50 D) and function. The graft remained attached and clear after DSEK in the eye with PBK, with BCVA of 20/30 and a CCT of 653 µm. One donor cornea can be used for two lamellar keratoplasties, DALK and DSEK. Although the described obstacles may prevent this approach from becoming widely used, it may prove useful when one is confronted with a need for an urgent anterior lamellar keratoplasty, a long list of cases for DSEK, and a shortage of donor corneas.

Relato de caso descrevendo o uso de uma córnea doadora para dois procedimentos de transplante: ceratoplastia anterior lamelar profunda (DALK) no caso de uma perfuração corneal iminente causada por necrose estromal por herpes vírus, e ceratoplastia com transplante de endotélio (DSEK) no olho com ceratopatia bolhosa em pseudofacia (PBK). A membrana de Descemet (DM), previamente desnudada pela necrose estromal, serviu como ponto de partida para o plano de dissecção e da criação do leito estromal para DALK. Os passos seguintes foram a excisão do estroma acometido até a borda da trepanação, transplante de um botão doador de aproximadamente 400-450 µm de espessura manualmente dissecado. As camadas posteriores restantes da córnea doadora, com a espessura de 100-150 µm, foram utilizadas para o procedimento DSEK no olho com PBK. A integridade do globo ocular foi mantida, e a acuidade visual melhor corrigida (BCVA) de 20/40 foi alcançada após DALK no olho com a perfuração corneal iminente. A espessura corneal central (CCT) de 430 µm abaixo da normal não interferiu com a curvatura anterior da córnea (43,50 x 45,50 D), nem com a sua função. O transplante de endotélio manteve-se tópico e transparente após DSEK no olho com a PBK, com uma BCVA de 20/30 e CCT de 653 µm. Uma córnea doadora pode ser utilizada para duas ceratoplastias lamelares, DALK e DSEK. Apesar de, devido os obstáculos descritos, pode não ser recomendada para o uso cotidiano, esta abordagem mostra-se útil nos casos da necessidade de uma ceratoplastia lamelar anterior de urgência, a longa lista para DESK e a falta de córneas doadoras.

INTACS followed by KeraRing intrastromal corneal ring segment implantation for keratoconus.

PURPOSE: To describe the visual and refractive outcomes in three eyes (two keratoconic patients) with previous intrastromal corneal ring segments (INTACS, Addition Technology Inc) that underwent adjuvant single KeraRing (Mediphacos) intrastromal corneal ring segment implantation. METHODS: Two keratoconic patients (three eyes) with implanted INTACS segments underwent an additional (without explanting previous INTACS) single KeraRing segment implantation. RESULTS: No intraoperative complications occurred. Six months postoperatively, uncorrected distance visual acuity improved from 20/100 and 20/200 to 20/32 and 20/40 in the right and left eyes, respectively, of patient 1, and from 20/400 to 20/50 in the treated right eye of patient 2. Corrected distance visual acuity improved from 20/50 and 20/100 to 20/30 and 20/32 in the right and left eyes, respectively, of patient 1 and from 20/200 to 20/40 in patient 2. Keratometric measurements improved from 51.00/45.70 to 47.00/44.60 diopters (D) and from 50.80/48.80 to 42.70/40.30 D in the right and left eyes, respectively, of patient 1, and from 49.30/45.70 to 45.60/44.10 D in patient 2. CONCLUSIONS: In keratoconic patients with INTACS in place, adjuvant single intrastromal corneal ring segment (KeraRing) implantation could improve visual and refractive outcome.

Effect of treatment sequence in combined intrastromal corneal rings and corneal collagen crosslinking for keratoconus.

PURPOSE: To compare 2 sequences of combined intrastromal corneal ring segment (ICRS) implantation and ultraviolet/riboflavin-mediated corneal collagen crosslinking (CXL) in progressive keratoconus. SETTING: Dunya Eye Hospital, Istanbul, Turkey. METHODS: In this prospective comparative randomized consecutive study, CXL was followed by ICRS implantation (Group 1) or ICRS implantation was followed by CXL (Group 2). Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, spherical equivalent (SE), manifest cylinder (cylinder), and mean keratometry (K) were compared preoperatively and postoperatively. RESULTS: The mean interval between treatments was 7 months +/- 2 (SD) (mean follow-up, 13 +/- 1 months). The mean UDVA and CDVA improved in both groups (UDVA: 0.07 +/- 0.09 to 0.25 +/- 0.12, Group 1, and 0.11 +/- 0.09 to 0.32 +/- 0.21, Group 2; CDVA: 0.24 +/- 0.11 to 0.41 +/- 0.20 and 0.22 +/- 0.16 to 0.55 +/- 0.2, respectively). The mean SE, cylinder, and mean K values decreased in both groups (SE: -7.13 +/- 3.34 D to -2.98 +/- 2.33 D, Group 1, and -7.05 +/- 5.54 D to -2.81 +/- 4.08 D, Group 2; cylinder: -4.38 +/- 2.03 D to -2.62 +/- 1.93 D and -4.68 +/- 2.60 D to -2.20 +/- 1.67 D, respectively; mean K: 52.47 +/- 4.01 D to 48.31 +/- 3.65 D and 52.06 +/- 4.93 D to 48.08 +/- 4.13 D, respectively). Overall, there was more improvement in CDVA, SE, and mean K in Group 2 than in Group 1. CONCLUSION: Implantation of ICRS followed by CXL resulted in greater improvement of keratoconus.

Intraoperative pachymetric measurements during corneal collagen cross-linking with riboflavin and ultraviolet A irradiation.

OBJECTIVE: To study central corneal pachymetric variations during corneal collagen cross-linking (CXL) treatment with the use of riboflavin and ultraviolet A irradiation (UVA). DESIGN: Prospective, noncomparative, interventional clinical study. PARTICIPANTS: Fifteen keratoconic patients (19 eyes) were enrolled. METHODS: All patients underwent riboflavin-UVA-induced corneal CXL. Intraoperative central corneal thickness (CCT) measurements using ultrasound pachymetry were performed during the procedure. Measurements were obtained after epithelial removal, after riboflavin drop instillation, and every 5 minutes (6 interval times) during UVA irradiation (30 minutes). MAIN OUTCOME MEASURES: Central corneal thickness measurements. RESULTS: Mean patient age was 26.9+/-6.5 years (range, 17-40 years). Ten were male and 5 were female. Mean preoperative CCT was 458.5+/-21.5 microm (range, 427-494 microm; 95% confidence interval [CI], 448-467 microm) and 415.7+/-20.6 microm (range, 400-468 microm; 95% CI, 406-426 microm) before and after epithelial removal, respectively. There was a statistically significant decrease (mean, 75 microm) of CCT between the epithelial removal interval (415.7+/-20.6 microm; range, 400-468 microm) and at the end of riboflavin solution instillation (340.7+/-22.9 microm; range, 292-386 microm; P<0.001). There was no statistically significant change in CCT during irradiation (P>0.05). There was no statistically significant difference between preoperative and 1-month postoperative endothelial cell count (preoperative, 2780+/-197 to 1-month postoperative, 2713+/-116; P = 0.14). No intraoperative, early postoperative, or late postoperative complications were observed in this patient series. CONCLUSIONS: During corneal CXL with the use of riboflavin and UVA irradiation, a statistically significant decrease of CCT was demonstrated.