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Chao DL, Rinella NT, Khanani AM, Wykoff CC, Kim GH. Cooling Anesthesia for Intravitreal Injection: Results of the Prospective Open-Label, Dose-Ranging COOL-1 Trial. Clin Ophthalmol 2021; 15:4659-4666. [PMID: 34916777 PMCID: PMC8670887 DOI: 10.2147/opth.s336653] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 11/05/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To evaluate the safety and efficacy of a novel medical device to provide cooling anesthesia to the eye as local anesthesia for intravitreal injections. Study Design First in human, open-label study of 43 subjects assessed at three different doses: −10°C for 20 seconds (group 1), −15°C for 15 seconds (group 2), and −15°C for 20 seconds (group 3). Main outcome measures were safety and pain of injection using a numeric rating scale (NRS). Results Cooling anesthesia did not result in any serious ocular adverse events. One grade 1 adverse event was a vasovagal response during cooling administration which resolved immediately after cooling. Mean NRS scores at the time of injection for each group ranged from 2.5 to 4.3 There was a statistically significant difference between pain scores of the 3 groups at injection in aggregate but not in pairwise comparisons (P value = 0.047). There was a statistically significant decrease in pain from injection to 5 minutes post injection in all groups (P value = 0.00008, 0.003, 0.0005 for groups 1, 2, 3, respectively) as well as from 5 minutes to 24–48 hours (P value = 0.00001, 0.018, and 0.0545 for groups 1, 2, 3, respectively). Conclusion The rapid cooling anesthesia device was well tolerated for achieving local anesthesia among patients receiving intravitreal injections with no serious ocular adverse events.
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Affiliation(s)
- Daniel L Chao
- Viterbi Family Department of Ophthalmology, University of California, San Diego, CA, USA
| | - Nicolas T Rinella
- Viterbi Family Department of Ophthalmology, University of California, San Diego, CA, USA
| | - Arshad M Khanani
- Sierra Eye Associates and University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Charles C Wykoff
- Retina Consultants of Texas, Retina Consultants of America; Blanton Eye Institute, Houston Methodist Hospital & Weill Cornell Medical College, Houston, TX, USA
| | - Gun-Ho Kim
- RecensMedical, Ulsan, Korea.,Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Korea
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Ruiz-Lozano RE, Garza-Garza LA, Davila-Cavazos O, Foster CS, Rodriguez-Garcia A. The clinical and pathogenic spectrum of surgically-induced scleral necrosis: A review. Surv Ophthalmol 2021; 66:594-611. [PMID: 33422510 DOI: 10.1016/j.survophthal.2020.12.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 12/23/2020] [Accepted: 12/28/2020] [Indexed: 11/20/2022]
Abstract
The onset of scleral necrosis after ocular surgery may have catastrophic ocular and systemic consequences. The two most frequent surgeries causing surgically-induced scleral necrosis (SISN) are pterygium excision and cataract extraction. Several pathogenic mechanisms are involved in surgically induced scleral necrosis. All of them are poorly understood. Ocular trauma increasing lytic action of collagenases with subsequent collagen degradation, vascular disruption leading to local ischemia, and immune complex deposition activating the complement system represents some of the events that lead to scleral necrosis. The complex cascade of events involving different pathogenic mechanisms and the patient's abnormal immune response frequently leads to delayed wound healing that predisposes the development of scleral necrosis. The management of SISN ranges from short-term systemic anti-inflammatory drugs to aggressive immunosuppressive therapy and surgical repair. Therefore, before performing any ocular surgery involving the sclera, a thorough ophthalmic and systemic evaluation must be done to identify high-risk patients that may develop SISN.
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Affiliation(s)
- Raul E Ruiz-Lozano
- Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Monterrey, Mexico
| | - Lucas A Garza-Garza
- Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Monterrey, Mexico
| | - Osvaldo Davila-Cavazos
- Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Monterrey, Mexico
| | - C Stephen Foster
- Massachusetts Eye Research and Surgery Institute, Waltham, MA, USA; Department of Ophthalmology, Harvard Medical School, Boston, MA, USA
| | - Alejandro Rodriguez-Garcia
- Tecnologico de Monterrey, School of Medicine and Health Sciences, Institute of Ophthalmology and Visual Sciences, Monterrey, Mexico.
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3
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Svistushkin MV, Kotova SL, Shekhter AB, Svistushkin VM, Akovantseva AA, Frolova AA, Fayzullin AL, Starostina SV, Bezrukov EA, Sukhanov RB, Timashev SF, Butnaru DV, Timashev PS. Collagen fibrillar structures in vocal fold scarring and repair using stem cell therapy: a detailed histological, immunohistochemical and atomic force microscopy study. J Microsc 2019; 274:55-68. [PMID: 30740689 DOI: 10.1111/jmi.12784] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Revised: 01/15/2019] [Accepted: 01/24/2019] [Indexed: 12/11/2022]
Abstract
Regenerative medicine opens new opportunities in the repair of cicatricial lesions of the vocal folds. Here, we present a thorough morphological study, with the focus on the collagen structures in the mucosa of the vocal folds, dedicated to the effects of stem cells on the vocal folds repair after cicatricial lesions. We used a conventional experimental model of a mature scar of the rabbit vocal folds, which was surgically excised with a simultaneous implantation of autologous bone marrow-derived mesenchymal stem cells (MSC) into the defect. The restoration of the vocal folds was studied 3 months postimplantation of stem cells and 6 months after the first surgery. The collagen structure assessment included histology, immunohistochemistry and atomic force microscopy (AFM) studies. According to the data of optical microscopy and AFM, as well as to immunohistochemical analysis, MSC implantation into the vocal fold defect leads not only to the general reduction of scarring, normal ratio of collagens type I and type III, but also to a more complete restoration of architecture and ultrastructure of collagen fibres in the mucosa, as compared to the control. The collagen structures in the scar tissue in the vocal folds with implanted MSC are more similar to those in the normal mucosa of the vocal folds than to those of the untreated scars. AFM has proven to be an instrumental technique in the assessment of the ultrastructure restoration in such studies. LAY DESCRIPTION: Regenerative medicine opens new opportunities in the repair of the vocal fold scars. Because collagen is a main component in the vocal fold mucosa responsible for the scar formation and repair, we focus on the collagen structures in the mucosa of the vocal folds, using a thorough morphological study based on histology and atomic force microscopy (AFM). Atomic force microscopy is a scanning microscopic technique which allows revealing the internal structure of a tissue with a resolution up to nanometres. We used a conventional experimental model of a mature scar of the rabbit vocal folds, surgically excised and treated with a mesenchymal stem cells transplant. Our morphological study, primarily AFM, explicitly shows that the collagen structures in the scarred vocal folds almost completely restore after the stem cell treatment. Thus, the modern microscopic methods, and especially AFM are instrumental tools for monitoring the repair of the vocal folds scars.
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Affiliation(s)
| | - Svetlana L Kotova
- Institute for Regenerative Medicine, Sechenov University, Moscow, Russia.,N.N. Semenov Institute of Chemical Physics, Moscow, Russia
| | - Anatoly B Shekhter
- Institute for Regenerative Medicine, Sechenov University, Moscow, Russia
| | | | - Anastasia A Akovantseva
- Institute of Photonic Technologies, Research Center 'Crystallography and Photonics', Moscow, Russia
| | | | - Alexey L Fayzullin
- Institute for Regenerative Medicine, Sechenov University, Moscow, Russia
| | | | | | | | - Sergey F Timashev
- N.N. Semenov Institute of Chemical Physics, Moscow, Russia.,National Research Nuclear University MEPhI, Moscow, Russia
| | - Denis V Butnaru
- Institute for Regenerative Medicine, Sechenov University, Moscow, Russia
| | - Peter S Timashev
- Institute for Regenerative Medicine, Sechenov University, Moscow, Russia.,N.N. Semenov Institute of Chemical Physics, Moscow, Russia.,Institute of Photonic Technologies, Research Center 'Crystallography and Photonics', Moscow, Russia
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4
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Uhlig MR, Magerle R. Unraveling capillary interaction and viscoelastic response in atomic force microscopy of hydrated collagen fibrils. NANOSCALE 2017; 9:1244-1256. [PMID: 28054696 DOI: 10.1039/c6nr07697a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The mechanical properties of collagen fibrils depend on the amount and the distribution of water molecules within the fibrils. Here, we use atomic force microscopy (AFM) to study the effect of hydration on the viscoelastic properties of reconstituted type I collagen fibrils in air with controlled relative humidity. With the same AFM tip, we investigate the same area of a collagen fibril with two different force spectroscopy methods: force-distance (FD) and amplitude-phase-distance (APD) measurements. This allows us to separate the contributions of the fibril's viscoelastic response and the capillary force to the tip-sample interaction. A water bridge forms between the tip apex and the surface, causing an attractive capillary force, which is the main contribution to the energy dissipated from the tip to the specimen in dynamic AFM. The force hysteresis in the FD measurements and the tip indentation of only 2 nm in the APD measurements show that the hydrated collagen fibril is a viscoelastic solid. The mechanical properties of the gap regions and the overlap regions in the fibril's D-band pattern differ only in the top 2 nm but not in the fibril's bulk. We attribute this to the reduced number of intermolecular crosslinks in the reconstituted collagen fibril. The presented methodology allows the mechanical surface properties of hydrated collagenous tissues and biomaterials to be studied with unprecedented detail on the nanometer scale.
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Affiliation(s)
- Manuel R Uhlig
- Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany.
| | - Robert Magerle
- Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany.
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Wong CW, Ang M, Tsai A, Phua V, Lee SY. A Prospective Study of Biometric Stability After Scleral Buckling Surgery. Am J Ophthalmol 2016; 165:47-53. [PMID: 26945723 DOI: 10.1016/j.ajo.2016.02.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 02/19/2016] [Accepted: 02/19/2016] [Indexed: 01/29/2023]
Abstract
PURPOSE To assess time to stabilization and factors associated with changes in biometric parameters after scleral buckling (SB). DESIGN Prospective case series. METHODS Seventeen eyes with primary rhegmatogenous retinal detachment (RRD) that underwent SB at the Singapore National Eye Centre were enrolled. SB surgery was performed using an encircling element and segmental buckle. Axial length (AL); anterior chamber depth (ACD), defined as the distance from the corneal epithelium to the anterior lens surface; anterior/posterior corneal curvature (K); and refraction were measured preoperatively and at week 1 and months 1, 3, 6, 9, and 12 postoperatively. Stability of each parameter was defined as the earliest time point at which there is no significant difference compared to its value at month 12. RESULTS AL increased (26.09 ± 1.46 to 26.51 ± 1.96, P = .01), ACD decreased (3.84 ± 0.47 to 3.32 ± 0.57, P < .001), and a myopic shift of 1.04 diopters (95% CI 0.03-2.05, P = .04) occurred at month 12. Anterior/posterior K were not significantly changed from baseline. AL stabilized at month 3 while ACD and spherical equivalent (SE) stabilized at week 1. Cryotherapy was associated with greater increase in AL (P = .001) and myopic shift (P = .02). More extensive segmental buckling was associated with greater increase in AL (P = .009) and myopic shift (P = .03). CONCLUSIONS Our study suggests that patients requiring cataract surgery after SB should have biometry performed no earlier than 3 months post SB surgery, and intraocular lens power calculation with a fourth-generation formula. A greater increase in AL and myopic shift was associated with cryotherapy and more extensive segmental buckling.
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Timashev PS, Kotova SL, Belkova GV, Gubar'kova EV, Timofeeva LB, Gladkova ND, Solovieva AB. Atomic Force Microscopy Study of Atherosclerosis Progression in Arterial Walls. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2016; 22:311-25. [PMID: 26843417 DOI: 10.1017/s1431927616000039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cardiovascular disease remains the leading cause of mortality worldwide. Here we suggest a novel approach for tracking atherosclerosis progression based on the use of atomic force microscopy (AFM). Using AFM, we studied cross-sections of coronary arteries with the following types of lesions: Type II-thickened intima; Type III-thickened intima with a lipid streak; Type IV-fibrotic layer over a lipid core; Type Va-unstable fibrotic layer over a lipid core; Type Vc-very thick fibrotic layer. AFM imaging revealed that the fibrotic layer of an atherosclerotic plaque is represented by a basket-weave network of collagen fibers and a subscale network of fibrils that become looser with atherosclerosis progression. In an unstable plaque (Type Va), packing of the collagen fibers and fibrils becomes even less uniform than that at the previous stages, while a stable fibrotic plaque (Vc) has significantly tighter packing. Such alterations of the collagen network morphology apparently, led to deterioration of the Type Va plaque mechanical properties, that, in turn, resulted in its instability and propensity to rupture. Thus, AFM may serve as a useful tool for tracking atherosclerosis progression in the arterial wall tissue.
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Affiliation(s)
- Peter S Timashev
- 1Institute of Laser and Information Technologies,2 Pionerskaya St.,142092 Troitsk,Moscow,Russia
| | - Svetlana L Kotova
- 2Department of Polymers and Composites,N.N.Semenov Institute of Chemical Physics,4 Kosygin St.,119991 Moscow,Russia
| | - Galina V Belkova
- 2Department of Polymers and Composites,N.N.Semenov Institute of Chemical Physics,4 Kosygin St.,119991 Moscow,Russia
| | - Ekaterina V Gubar'kova
- 3Nizhny Novgorod State Medical Academy,10/1 Minin and Pozharsky Sq.,603005 Nizhny Novgorod,Russia
| | - Lidia B Timofeeva
- 3Nizhny Novgorod State Medical Academy,10/1 Minin and Pozharsky Sq.,603005 Nizhny Novgorod,Russia
| | - Natalia D Gladkova
- 3Nizhny Novgorod State Medical Academy,10/1 Minin and Pozharsky Sq.,603005 Nizhny Novgorod,Russia
| | - Anna B Solovieva
- 2Department of Polymers and Composites,N.N.Semenov Institute of Chemical Physics,4 Kosygin St.,119991 Moscow,Russia
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7
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Stanley A, Pedersen E, Brakebusch C, Quondamatteo F. Changes in dermal matrix in the absence of Rac1 in keratinocytes. J Anat 2016; 228:826-37. [PMID: 26889750 DOI: 10.1111/joa.12442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2015] [Indexed: 11/30/2022] Open
Abstract
Keratinocytes, in response to irritants, secrete pro-inflammatory mediators which recruit and activate immune and mesenchymal cells, including fibroblasts, to repair the skin. Fibroblasts respond by synthesising collagen and promoting the crosslinking extracellular matrix (ECM). We recently showed that the deletion of Rac1 in keratinocytes causes heightened inflammation due to aberrant crosstalk with immune cells. Indeed, the skin of these mice shows a higher inflammatory response to the induction of irritant contact dermatitis (ICD), and also even to treatment with a vehicle alone, compared with controls. As inflammation is intimately linked with fibrotic disease in the skin, this raised the question as to whether this deletion may also affect the deposition and arrangement of the dermal ECM. This study assessed the effects of Rac1 deletion in keratinocytes and of the heightened inflammatory status by induction of ICD on the tissue localisation and arrangements of dermal collagen. Qualitative analysis did not reveal evidence for the formation of pathologies in the dermis. However, quantitative analysis did reveal some perturbations in the dermal matrix, namely that only the combination of the lack of Rac1 and ICD affects the architectural organisation of the dermal collagen, and that a higher inflammatory state in the tissue (i.e. when Rac1 is deleted in the keratinocytes or ICD is induced in the skin, or a combination of both) influences the diameter of the collagen fibrils. It is proposed that this increase in the diameter of collagen fibrils due to inflammation may serve as pre-fibrotic marker enabling earlier determination of fibrosis and earlier treatment. This study has revealed previously unknown effects on the ECM due to the deletion of Rac1 in keratinocytes.
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Affiliation(s)
- Alanna Stanley
- Skin and ECM Research Group, Anatomy NUI Galway, Galway, Ireland
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Spitzner EC, Röper S, Zerson M, Bernstein A, Magerle R. Nanoscale Swelling Heterogeneities in Type I Collagen Fibrils. ACS NANO 2015; 9:5683-5694. [PMID: 25961780 DOI: 10.1021/nn503637q] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The distribution of water within the supramolecular structure of collagen fibrils is important for understanding their mechanical properties as well as the biomineralization processes in collagen-based tissues. We study the influence of water on the shape and the mechanical properties of reconstituted fibrils of type I collagen on the nanometer scale. Fibrils adsorbed on a silicon substrate were imaged with multiset point intermittent contact (MUSIC)-mode atomic force microscopy (AFM) in air at 28% relative humidity (RH) and in a hydrated state at 78% RH. Our data reveal the differences in the water uptake between the gap and overlap regions during swelling. This provides direct evidence for different amounts of bound and free water within the gap and overlap regions. In the dry state, the characteristic D-band pattern visible in AFM images is due to height corrugations along a fibril's axis. In the hydrated state, the fibril's surface is smooth and the D-band pattern reflects the different mechanical properties of the gap and overlap regions.
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Affiliation(s)
- Eike-Christian Spitzner
- †Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
| | - Stephanie Röper
- †Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
| | - Mario Zerson
- †Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
| | - Anke Bernstein
- ‡Orthopädie und Traumatologie, Universitätsklinikum Freiburg, D-79095 Freiburg, Germany
| | - Robert Magerle
- †Fakultät für Naturwissenschaften, Technische Universität Chemnitz, D-09107 Chemnitz, Germany
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Kotova SL, Timashev PS, Guller AE, Shekhter AB, Misurkin PI, Bagratashvili VN, Solovieva AB. Collagen structure deterioration in the skin of patients with pelvic organ prolapse determined by atomic force microscopy. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2015; 21:324-333. [PMID: 25740571 DOI: 10.1017/s1431927615000148] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We used atomic force microscopy (AFM) to diagnose pathological changes in the extracellular matrix (ECM) of skin connective tissue in patients with pelvic organ prolapse (POP). POP is a common condition affecting women that considerably decreases the patients' quality of life. Deviations from normal morphology of the skin ECM from patients with POP occur including packing and arrangement of individual collagen fibers and arrangement of collagen fibrils. The nanoindentation study revealed significant deterioration of the mechanical properties of collagen fibril bundles in the skin of POP patients as compared with the skin of healthy subjects. Changes in the skin ECM appeared to correlate well with changes in the ECM of the pelvic ligament tissue associated with POP. AFM data on the ECM structure of normal and pathologically altered connective tissue were in agreement with results of the standard histological study on the same clinical specimens. Thus, AFM and related techniques may serve as independent or complementary diagnostic tools for tracking POP-related pathological changes of connective tissue.
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Affiliation(s)
- Svetlana L Kotova
- 1N.N. Semenov Institute of Chemical Physics,Department of Polymers and Composites,4 Kosygin St.,119991,Moscow,Russia
| | - Peter S Timashev
- 2Institute of Laser and Information Technologies,2 Pionerskaya St.,142092,Troitsk,Moscow,Russia
| | - Anna E Guller
- 3Research Institute of Molecular Medicine,I.M. Sechenov First Moscow Medical University,8 Trubetskaya St.,Bldg. 2,119991,Moscow,Russia
| | - Anatoly B Shekhter
- 3Research Institute of Molecular Medicine,I.M. Sechenov First Moscow Medical University,8 Trubetskaya St.,Bldg. 2,119991,Moscow,Russia
| | - Pavel I Misurkin
- 1N.N. Semenov Institute of Chemical Physics,Department of Polymers and Composites,4 Kosygin St.,119991,Moscow,Russia
| | - Victor N Bagratashvili
- 2Institute of Laser and Information Technologies,2 Pionerskaya St.,142092,Troitsk,Moscow,Russia
| | - Anna B Solovieva
- 1N.N. Semenov Institute of Chemical Physics,Department of Polymers and Composites,4 Kosygin St.,119991,Moscow,Russia
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Kim YH, Jin KH, Kim JH, Park DJ, Choi S, Park HK. Molecular and chemical investigations and comparisons of biomaterials for ocular surface regeneration. Microsc Res Tech 2013; 77:183-8. [PMID: 24357544 DOI: 10.1002/jemt.22326] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 12/07/2013] [Indexed: 11/11/2022]
Abstract
This study investigated and compared the ultrastructural and chemical properties of representative biomaterials for ocular surface regeneration: a human amniotic membrane (AM) in a basal plate, a human AM in reflected chorion, a preserved AM, and a human corneo-scleral tissue. Assessments of the morphological differences in the extracellular matrices were evaluated by hematoxylin-eosin, Masson's trichrome (for total collagen), and picrosirius-red (for newly synthesized collagen) staining. Assessments of the changes in the molecular structures and chemical compositions of the biomaterials for ocular surface regeneration were evaluated by Raman spectroscopy. A placental AM (52 %) was a dense and thick collagenous structure compared to a reflected AM (23 %). The spectroscopy did not obtain any structural information for a preserved AM. The cornea group (100 %, control) and sclera group (104 %) showed the collagen lamellae and interfibrillar spacing, and a slight inflammatory reaction with more fibrous and granulomatous tissues. There was a formation of newly synthesized collagen in a placental AM, while there were few collagen components in a reflected AM. Human AM tissues showed consistent Raman spectra and the characteristic collagen bands, similar to the corneal and scleral tissues. Therefore, these findings suggest that human placental AM and reflected AM are structurally suitable for scleral and corneal surface regeneration, respectively, while human placental or preserved AM and reflected AM are molecularly and chemically suitable for corneal and scleral surface regeneration, respectively.
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Affiliation(s)
- Yeon-Hee Kim
- Department of Obstetrics and Gynecology, The Catholic University of Korea, Kyonggi-do, 480-717, Korea
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