Deep anterior lamellar keratoplasty and penetrating keratoplasty in macular corneal dystrophy: comparison of visual and topographic outcomes and complications

ABSTRACT Purposes: This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy. Methods: In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates. Results: After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test). Conclusion: Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.

Complications of Descemet stripping endothelial keratoplasty – A retrospective interventional study at a tertiary eye care center in Southern India

Purpose: To analyze the visual outcome and complications of Descemet stripping endothelial keratoplasty (DSEK) with their management in 256 eyes at a tertiary eye care center in southern India. Methods: This is a retrospective interventional study of 62 months duration conducted at a tertiary eye care center in southern India. Two hundred and fifty?six eyes of 205 patients were included in the study after obtaining written informed consent from the patients. All cases of DSEK were performed by a single experienced surgeon. In all cases, donor dissection was performed manually. A Sheet’s glide was inserted through the temporal corneal incision and donor button was placed on the Sheet’s glide with the endothelial side down. The lenticule was separated and inserted into the anterior chamber by pushing the lenticule into the anterior chamber using Sinskey’s hook. Any complication, either intraoperative or postoperative, was recorded and managed either medically or by appropriate surgical means. Results: The mean best corrected visual acuity (BCVA) before surgery was CF?1 m, which improved to 6/18 after surgery. Intraoperative donor graft perforation during dissection was seen in 12 cases, thin lenticule in three eyes, and repeated artificial Anterior Chamber (AC) collapse in three eyes. Dislocation of lenticule was the most common complication seen in 21 eyes, which was managed by graft repositioning and rebubbling. Eleven cases had minimal separation of the graft and seven cases had interface haze. Pupillary block glaucoma was seen in two cases that resolved with partial release of bubble. Surface infiltrate was seen in two cases, which was managed with topical antimicrobial agents. Primary graft failure was seen in two cases. Conclusion: DSEK is a promising alternative to penetrating keratoplasty for corneal endothelial decompensation, but it also has its own merits and limitations, and most often, merits overweigh limitations.

Femtosecond laser-assisted laser in situ keratomileusis for the correction of high myopia in Meesmann corneal dystrophy: a case report / Femto-LASIK para correção de alta miopia na distrofa corneana de Meesmann: relato de caso

ABSTRACT The patient was a 26-year-old woman who had manifest refraction and uncorrected and corrected distance visual acuities of -7.00 × -4.50 at 175°, 20/400, and 20/25, respectively, in the right eye, and -3.25 × -5.25 at 179°, 20/200, and 20/25, respectively, in the left eye. In the right and left eyes, the mean corneal thicknesses were 733 and 749 µm, and the maximum epithelial thicknesses were 70 and 68 µm, respectively. Myriads of intraepithelial cysts were observed in the slit-lamp examination. At 30 months after femtosecond laser-assisted laser in situ keratomileusis (femto-LASIK), the manifest refraction and uncorrected and corrected distance visual acuities were respectively 0.00 × -1.25 at 55°, 20/25, and 20/20 in right eye, and 0.00 × -0.50 at 135°, 20/20, and 20/20 in the left eye. In this case of Meesmann dystrophy, myopia was successfully treated with thick flap femto-LASIK without complications or ectasia.

RESUMO A paciente era uma mulher de 26 anos com refração manifesta, acuidade visual para longe não corrigida e corrigida de -7,00 × -4,50 a175°, 20/400 e 20/25 no olho direito e -3,25 × -5,25 a 179°, 20/200 e 20/25 no olho esquerdo. A espessura média da córnea foi de 733 e 749 µm, e a espessura epitelial máxima foi de 70 e 68 µm, respectivamente no olho direito e no esquerdo. Inúmeros cistos intraepiteliais foram observados no exame com lâmpada de fenda. Trinta meses após o femto-LASIK, a refração manifesta, a acuidade visual para longe não corrigida e corrigida eram respectivamente de 0,00 × -1,25 a 55°, 20/25 e 20/20 no olho direito e 0,00 × -0,50 a 135°, 20/20 e 20/20 no olho esquerdo. Neste caso de distrofia de Meesmann, a miopia foi tratada com sucesso com femto-LASIK de retalho espesso sem complicações ou ectasia.

Demographic profile and clinical characteristics of Fuchs’ endothelial corneal dystrophy in a tertiary eye care center

Purpose: This study was performed to determine the demographic profile and clinical characteristics in patients with Fuchs’ endothelial corneal dystrophy (FECD) reporting to a tertiary eye care center in India. It is a retrospective, single?center, observational study. Methods: The study included 280 patients (559 eyes) diagnosed with FECD presenting between January 2013 and December 2020. The data was collected from the electronic medical record system of the institute. Patient data included demographic features, clinical characteristics, investigations, and surgical interventions. Results: The mean age of the patients was 62 years. Late?onset FECD (95.7%) was more common than early?onset FECD (4.3%). Male: female ratio for late?onset FECD and early?onset FECD was 1:1.65 and 3:1, respectively. More than one?third of the patients had associated systemic history. Preexisting ocular diseases were seen in 5.9% of eyes. Blurring of vision was seen in 383 eyes (68.5%), 13 eyes (2.1%) had glare, and 163 eyes (29.2%) were asymptomatic. A total of 113 surgical interventions were done in 108 eyes (including repeat transplants). Only cataract surgery was done in 40 (7.2%) eyes, whereas penetrating keratoplasty, Descemet stripping endothelial keratoplasty, and Descemet membrane endothelial keratoplasty without or with cataract surgery (sequential or triple procedure) were done in 12 (2.1%), 47 (8.4%), and 14 (2.5%) eyes, respectively. Conclusion: Patients with FECD present mostly during the sixth decade. Posterior lamellar keratoplasty is the most common transplant procedure being performed on FECD patients

In vivo confocal microscopic observations of 49 patients with posterior polymorphous corneal dystrophy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To explore the imaging features of 49 patients with posterior polymorphous corneal dystrophy(PPCD)by in vivo confocal microscopy(IVCM).METHODS: Retrospective case series study. A total of 49 patients(86 eyes), including 32 males and 17 females diagnosed with PPCD between January 2013 and January 2021 were collected. The mean age was 42.5±22.9 years. All patients were scanned by IVCM to analyze the density of corneal endothelial cells and described IVCM characteristics of different types of PPCD.RESULTS: The number of endothelial cells in the lesion area of all patients was lower than that in the peripheral area. Under IVCM, 44 eyes(51%)were categorized into type 1 PPCD(vesicular lesions), characterized by single or multiple, central round or irregular crater-like lesion on paracentral corneal endothelial layer; 16 eyes(19%)were categorized into type 2 PPCD(band lesions), which displayed curved and raised edge with scattered or banded-distributed gutta-like lesion between edges. Type 3 PPCD(diffuse lesion)were in 26 eyes(30%), which showed that endothelial cells were missing in many areas. The blurred images of endothelium in most areas featured with spikes lined in a streak, and the clear images in some areas featured with a band lesions. Two patients were followed up for 4-5a. The IVCM images showed different lesions, including the decrease of central corneal endothelial cell density and the iron deposit in the corneal epithelium, etc.CONCLUSION: IVCM is able to scan the characteristic microstructural alterations at the level of endothelium and Descemet membrane in patients with PPCD, and provide an effective image diagnosis for PPCD.

Guidelines for the application of artificial intelligence in the diagnosis of anterior segment diseases(2023) / 国际眼科杂志(Guoji Yanke Zazhi)

This paper aims to delve deeply into the practical guidelines for the application of artificial intelligence(AI)in the diagnosis of anterior ocular diseases in ophthalmology. Given the complexities and variability inherent in the images associated with the research of anterior segment diseases, AI has traditionally found its principal application in the sphere of posterior segment diseases within ophthalmology. However, with the evolution and advancement of AI technologies, notably machine learning and deep learning, alongside an exponential surge in anterior segment electronic image data, the implementation of AI in the domain of corneal, conjunctival, lens, and eyelid disease is not only feasible but has become a reality. The Ophthalmic Imaging and Intelligent Medicine Branch of the Chinese Medical Education Association, in tandem with the Ophthalmology Professional Committee of the International Translational Medicine Association, have orchestrated a consortium of experts. These specialists have synthesized the most recent progressions, both nationally and internationally, in the application of AI in the diagnosis of anterior ocular diseases. This includes its use in corneal, conjunctival, lens, and eyelid diseases, and provides an analysis of the current challenges faced as well as the future directions of development. This guideline has been formulated through several iterations of thoughtful discussion and revisions. Its purpose is to empower clinical ophthalmologists with a reliable framework to facilitate the enhanced application of AI in diagnostic decision-making and clinical research for anterior ocular diseases.

Distrofia corneal de Meesmann en paciente con queratotomía hexagonal / Meesmann corneal dystrophy in a patient with hexagonal keratotomy

RESUMEN Las distrofias corneales constituyen un grupo de enfermedades hereditarias que suelen ser bilaterales y simétricas, las cuales progresan lentamente y sin relación con factores ambientales o sistémicos. Se presenta una paciente de raza blanca, de 45 años de edad, remitida al Servicio de Córnea del Instituto Cubano de Oftalmología "Ramón Pando Ferrer", quien refirió sensación de cuerpo extraño, sensibilidad a la luz y mala visión de ambos ojos, así como antecedente de queratotomía hexagonal hacía aproximadamente 20 años. En lámpara de hendidura se observaron en el epitelio numerosas lesiones puntiformes en forma de vesículas claras, semejantes a ampollas, distribuidas paracentralmente, que respetaban ligeramente el centro, con espacios de córnea transparente entre ellas y mejor visibilidad de las lesiones en retroiluminación. En la microscopia confocal se observaron en el ojo derecho estructuras redondas u ovales, de forma quística, hiporreflectivas. En el ojo izquierdo se encontraron imágenes difusas hiperreflectivas en el epitelio corneal basal. Se detectó la presencia de nervios corneales tortuosos, de aspecto fragmentado en ambos ojos. Se consideró como diagnóstico la distrofia de Meesmann y se realizó queratectomía superficial, con lo cual se logró alivio de la sintomatología de la paciente(AU)

ABSTRACT Corneal dystrophies are a group of hereditary diseases often bilateral and symmetrical which progress slowly and without any relationship to environmental or systemic factors. A case is presented of a white 45-year-old female patient referred to the Cornea Service of Ramón Pando Ferrer Cuban Institute of Ophthalmology, who reported a foreign body sensation, light sensitivity and poor vision in both eyes, as well as a history of hexagonal keratotomy from approximately 20 years before. Slit lamp examination revealed numerous punctiform lesions in the form of clear blister-like vesicles distributed paracentrally and slightly sparing the center, with transparent cornea spaces between them and better visibility of the lesions under retroillumination. Confocal microscopy showed round or oval cystic and hyporeflective structures in the right eye, whereas the left eye exhibited diffuse hyperreflective images in the basal corneal epithelium. Tortuous corneal nerves of a fragmented appearance were detected in both eyes. A Meesmann dystrophy diagnosis was considered and superficial keratectomy was performed, with which the patient's symptoms were relieved(AU)

Research progress of descemetorhexis without endothelial keratoplasty promoting corneal endothelial regeneration / 国际眼科杂志(Guoji Yanke Zazhi)

@#Endothelial dysfunctionis traditionally considered irreversible, and endothelial keratoplasty(EK)is almost the only treatment available. Recently, however, a surgery called descemetorhexis without endothelial keratoplasty(DWEK)can regenerate the central corneal endothelial cells in patients with Fuchs endothelial corneal dystrophy(FECD), and local Rho-associated kinase inhibitor can enhance its efficacy.

Functional research progress of UBIAD1 and pathogenesis of SCCD / 国际眼科杂志(Guoji Yanke Zazhi)

@#The molecular basis of schnyder crystalline corneal dystrophy(SCCD)is UBIAD1 gene mutation. The pathogenesis of SCCD includes conformational change of UBIAD1 protein which leads to loss of combination with GGpp compounds. UBIAD1-HMG CoA reductase complexes can't be separated, and the rate-limiting enzyme can't dissociate from endoplasmic reticulum to cytoplasm, which results in loss of recognition and degradation by the proteasome. The direct consequence is the gradual accumulation and biosynthesis of cholesterol and non-sterol isoprenoids compounds in the cell. This paper reviews the clinical manifestation, molecular basis, pathogenesis of SCCD and the function of UBIAD1 which provide guidance for molecular diagnosis and treatment of SCCD and pave the way for elucidating the function of UBIAD1 <i>in vivo</i>.

A self-controlled study on corneal nerve invasion phenomenon of Bowman's membrane in patients with ⅢA lattice corneal dystrophy / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To analyze and study the corneal nerve invasion phenomenon of Bowman's membrane in patients with IIIA lattice corneal dystrophy by confocal laser scanning microscopy. Quantitative analysis of 10a continuous observation image data was performed, followed by self-control studies.<p>METHODS: A total of 10 patients(13 eyes)with IIIA Lattice corneal dystrophy were continuously examined by confocal laser scanning microscopy. The data were observed and analyzed. <p>RESULTS: The normal corneal nerve of Bowman's membrane(Grade 0)of IIIA LCD patients gradually decreased with the prolongation of observation time. The nerves of grade I to V involved(amyloid-wrapped nerve fibers)gradually increased correspondingly. So suggested that the corneal nerve invasion of Bowman's membrane(amyloid deposits)in patients with IIIA LCD were gradually increasing with time. <p>CONCLUSION: In patients with type ⅢA lattice corneal dystrophy, there is a neurotropic phenomenon in Bowman's membrane, which gradually worsens with the aggravation of the lesion. This lesion can explain the recurrent epithelial damage of the IIIA LCD from some degrees. Continuous observation of patients with type IIIA LCD by corneal laser confocal microscopy can well understand the development of the lesion and explain its clinical manifestations.

Functional research progress of UBIAD1 and pathogenesis of SCCD / 国际眼科杂志(Guoji Yanke Zazhi)

@#The molecular basis of schnyder crystalline corneal dystrophy(SCCD)is UBIAD1 gene mutation. The pathogenesis of SCCD includes conformational change of UBIAD1 protein which leads to loss of combination with GGpp compounds. UBIAD1-HMG CoA reductase complexes can't be separated, and the rate-limiting enzyme can't dissociate from endoplasmic reticulum to cytoplasm, which results in loss of recognition and degradation by the proteasome. The direct consequence is the gradual accumulation and biosynthesis of cholesterol and non-sterol isoprenoids compounds in the cell. This paper reviews the clinical manifestation, molecular basis, pathogenesis of SCCD and the function of UBIAD1 which provide guidance for molecular diagnosis and treatment of SCCD and pave the way for elucidating the function of UBIAD1 <i>in vivo</i>.

Research progress of Schnyder crystalline corneal dystrophy in molecular basis and clinic / 国际眼科杂志(Guoji Yanke Zazhi)

@#Schnyder crystalline corneal dystrophy(SCCD)is a rare autosomal dominant genetic disorder that occurs in bilateral corneas and is associated with crystalline opacification. SCCD is an inherited eye disease and distributes equally in both man and woman. Clinical research revealed that corneal crystalline turbidity resulted from the abnormal accumulation of cholesterol, phospholipid and other lipids in the corneal epithelium and stroma. The occurrence of SCCD is related to abnormal lipid metabolism caused by UBIAD1 mutation, but the molecular basis of the disease is unknown. This paper reviews the discovery and developmental history of SCCD, the molecular basis of SCCD and its clinical research, which provides guidance for the diagnosis and treatment of SCCD and the elucidation of pathogenic molecular mechanism.

Deep anterior lamellar keratoplasty outcomes in macular and granular corneal dystrophy – A comparative cross-sectional study

Purpose: To compare the functional and anatomical outcomes (in terms of graft uptake and rejection/failure) of deep anterior lamellar keratoplasty (DALK) in stromal corneal dystrophy (macular and granular). Methods: Sixteen eyes with macular corneal dystrophy (MCD; group A) and 10 eyes with granular corneal dystrophy (GCD; group B) underwent successful DALK by big bubble technique or layer-by-layer dissection. Results: Both groups showed significant improvement in their best-corrected visual acuity postoperatively (postoperative P value in MCD and GCD was 0.00001 and 0.0008, respectively) with no statistically significant differences between the two groups (P = 0.77) at 1 year. Postoperative endothelial count did not drop significantly in group A (MCD, P= 0.1553). Only in seven eyes preoperative endothelial count could be obtained (due to dense stromal corneal opacity), but there was a significant endothelial count difference between preoperative and postoperative count in group B (GCD, P= 0.0405) at the end of 1 year postoperatively which could be because of age and stage of disease (advanced granular dystrophy) and also because of small sample size of GCD compared with MCD. Intergroup comparison between the two groups showed no statistically significant difference (P = 0.6353) with good postoperative outcome in both groups. Conclusion: DALK can be successfully done in both groups and results are comparable. However, long-term outcomes on a large scale need to be further evaluated.

Iridocorneal Endothelial Syndrome with Features of Posterior Polymorphous Corneal Dystrophy

PURPOSE: To report a case of iridocorneal endothelial syndrome, which overlapped with some of the features of posterior polymorphous corneal dystrophy. CASE SUMMARY: A 61-year-old female presented with tearing pain and blurred vision in her left eye, which was aggravated in the morning. The symptom started approximately 1 year prior to her visit. At the initial visit, the visual acuities were 1.0 in both eyes and the intraocular pressures were normal. On slit-lamp examination, a single pair of horizontal parallel lines was observed at the central corneal endothelial layer in the right eye. In contrast, multiple pairs of oblique parallel lines were observed in the left eye. The lines of the lesions were more prominent and wavier in the left eye than those of the right eye. The overlying cornea was clear, and the corneal thicknesses were in the normal range in both eyes. Using a gonioscopic examination, localized peripheral anterior synechiae were observed only in the left eye. The pupil and iris were normal in both eyes. On specular microscopic examination, the corneal endothelial cell size in the right eye increased and the corneal endothelial density decreased to 668 cells/mm². In the left eye, multiple abnormal endothelial cells with dark-light reversal were observed. In conclusion, the patient was subsequently diagnosed with iridocorneal syndrome, rather than posterior polymorphous corneal dystrophy. CONCLUSIONS: Posterior polymorphous corneal dystrophy and iridocorneal endothelial syndrome may present with many similarities. Therefore, in cases of uncertain diagnosis, an understanding of the clinical features is important for proper diagnosis.

Study of TGFBI gene mutations in the patients with corneal dystrophy in northeast of China / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To explore the mutation type of TGFBI gene in a lattice-like corneal dystrophy(LCD)family in northeast China. <p>METHODS: A basic ophthalmologic examination was performed on the patients and two normal persons in the family. Genomic DNA of three affected, two unaffected family members and 50 normal individuals was extracted from peripheral leukocytes. All exons of TGFBI were amplified by polymerase chain reaction(PCR)methods and direct sequencing was carried out for mutation analysis. <p>RESULTS: A missense mutation(c.370C>T)in exon 4 of TGFBI led to an amino acid substitution R124C in the TGFBI protein in all affected family members, but the mutation was not detected in normal subjects of the family and control individuals. <p>CONCLUSION: We conclude that the novel mutation R124C causes lattice corneal dystrophy type I in the studied family. It was verified that R124C is a hot spot mutation in LCD I.

Advances in the treatment of macular corneal dystrophy / 国际眼科杂志(Guoji Yanke Zazhi)

@#Macular corneal dystrophy(MCD)refers to corneal stromal dystrophy, which can cause progressive visual field defects. MCD belongs to autosomal recessive disease. Mutation of CHST 6 gene is considered to be a pathogenic factor. In general, full-thickness penetrating keratoplasty has become a standard treatment for improving vision. Now more advanced surgical interventions such as deep anterior lamellar keratoplasty(DALK)and phototherapeutic keratectomy(PTK)have also been shown to be important in the treatment of MCD. Some new technologies, such as gene targeting therapy and enzyme replacement therapy, are also being studied as potential permanent solutions for MCD. The pathogenesis, genetic basis, clinical manifestations, treatment and prognosis of this disease are reviewed in this paper.

Lithium chloride promotes the proliferation and autophagy of corneal stromal fibroblasts by TGFBI / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To study the expressions of TGFBI and microtubule-associated protein 1 light chain 3 alpha(LC3)in granular corneal dystrophy, and the influences of lithium chloride(LiCl)on corneal stromal fibroblast cell proliferation by TGFBI. <p>METHODS: Immunohistochemistry and Western-blot assays were used to detect the expression levels of TGFBI and LC3 in corneal dystrophy and normal corneal tissues. TGFBI overexpression vector was transfected into corneal stromal fibroblasts, and then the cells were treated with 5, 10, 20, 40mmol/L LiCl for different times(0, 1, 6, 12h), and Western-blot assay was performed to evaluate the expression levels of TGFBI and LC3, and CCK-8 assay was carried out to assess cell proliferation activity.<p>RESULTS: TGFBI and LC3 were highly expressed in corneal tissues of patients with corneal dystrophy. TGFBI overexpression inhibited the proliferation ability of corneal stromal fibroblasts(<i>P</i><0.05). LiCl inhibited the expression levels of TGFBI and LC3, and enhanced the cell proliferation activity in corneal stromal fibroblasts transfected with mutant TGFBI(<i>P</i><0.05).<p>CONCLUSION: LiCl promoted the proliferation and autophagy of corneal stromal fibroblasts, and its mechanism may be related to down regulated expressions of TGFBI and LC3.

Primary graft failure after big bubble deep anterior lamellar keratoplasty in macular corneal dystrophy

Macular corneal dystrophy is autosomal recessive dystrophy characterized by deposits of abnormal glycosaminoglycans in stromal lamellae and within endothelial cells. Deep anterior lamellar keratoplasty is successful in the management of this dystrophy. We herein describe three cases of primary graft failure after uneventful big bubble deep anterior lamellar keratoplasty for macular corneal dystrophy.