Recent Advances in Ophthalmology–13 HV Nema, Nitin Nema
INDEX
Page numbers followed by f refer to figure and t refer to table.
A
Acanthamoeba 129
Accommodation failure 244
Achromatopsia 244
Acinetobacter baumannii 113
Acne vulgaris 264
Acquired nystagmus 235
signs in 243t
Acquired red-green dyschromatopsia 43
Acrylic IOLs 135
Acyclovir resistance 20
Adeno-associated virus vectors 165, 168
Adnexa lacrimal glands 125
Advanced glycation end products 139, 141f
Aflibercept 150, 155
Agents of phototoxicity 186
All India Ophthalmological Society 114
Amikacin 104
Amniotic membrane 28
transplant 18
Amphotericin B 104
Amyloid-β targets 163
Ancillary investigations 39
role of 51
Ancillary tests 277
Aneurysms 265
Angiomatous proliferation 171
Angiotensin converting enzyme 50, 147
Angle hypopyon 268
Angular vein 219f
Ankyrin repeat protein, designed 165, 167
Anterior chamber reaction with hypopyon 120f
Anterior venous drainage 219f
Anticoagulants 171
Anti-inflammatory therapies 161
Anti-neutrophilic cytoplasmic antibody 278
Anti-oxidative stress therapies 161, 163
Antiplatelet agents, role of 171
Anti-platelet-derived growth factor agents 165, 166
Anti-tubercular drug 43
ocular side-effects of 43t
Anti-tubercular therapy 42
Anti-vascular endothelial growth factor
agents 59,
drugs 165, 175
injection 128
therapy 150
Aperiodic alternating nystagmus 238
Arcuate scotoma, inferior 88f, 92f
Argon-fluoride excimer laser 1
Arteriovenous malformations 208
Arthritis 263
Aspergillus species 129
Automated nystagmus acuity function 239, 240
Azathioprine 53
Azopt eye drops 245f
B
Bacillus cereus 128, 136
Bacillus species 100
Bacterial endophthalmitis 100
Bacterial endotoxin residues 118
Balanced salt solution 118
Band-shaped keratopathy 51
Behçet posterior uveitis 272f
Behçet's disease 261, 263, 263t, 270f, 271f, 237f, 274t, 278, 278t, 279
in children 273
in pregnancy 274
prevalence of 262t
sex ratio of 262t
Behçet's eye disease 281
Behçet's ocular disease 283
Behçet's patients 265
Behçet's uveitis 263, 275, 279, 282
Behçet's vasculitis 273f
Bevacizumab 150, 155
Biomechanical response, coefficient of 5
Birdshot retinochoroidopathy 51
Birefrigerant interstitial crystals in kidney, depositoin of 258f
Blau syndrome 51
Blind spot 211f
enlarged 210f
Blood pressure control 147
Blue-light hazard 186
Borreliosis 36
Bronchoalveolar lavage 46, 52
Brucellosis 36
Budd-Chiari syndrome 265
Bullous keratopathy 16
C
Candida 136
albicans 129
chorioretinitis 136
species 100, 129
Cardiac disease 263
Cardiac manifestations 265
Carotico-cavernous fistula 218, 219f
Carotid artery, internal 207, 223
Carotid cavernous fistula 208, 218
Cataract 51, 54
surgery 14, 281
after 15f
Cavernous aneurysm 217
neck of 217f
Cavernous carotid artery 208
Cavernous internal carotid artery aneurysms 215
Cavernous sinus 219f, 222f
Cefazoline 104
Ceftazidime 104, 104f
Cell based therapies 26
Central corneal thickness 86
Central nervous system disease 263
Central scotomas 43
Cerebellar artery, superior 208
Cerebellar hemispheres 243
Cerebral angiogram 206
findings 208, 212, 215, 223, 225
Cervicomedullary junction 243
Chalky white retinitis 270
Chemoreduction 197
Chemotherapy 197
Children's Hospital Los Angeles 194
Chorioretinal degeneration, diffuse 271f
Choroidal blood flow enhancing agents 161, 164
Choroidal granuloma 40, 48
Choroidal invasion 201
Choroidal neovascular membrane 160
Choroidal neovascularization 171
Choroidal polyp 171
Ciclosporin-A 280
Clindamycin, intravitreal injection of 62
Cluster infections 114
Cochrane systemic 17
Collagen cross-linking 14
Computer-assisted tomography 41
Conbercept 166
Confocal microscopy in smile 7
Confocal scanning laser ophthalmoscope 69, 82
Confusional states 263
Congenital nystagmus waveforms 235
Congenital stationary night blindness 244
Conjunctiva 125
Conjunctival granulomas 47
Conjunctival limbal autografts 26
Contact lenses 244
Control cardiovascular risk in diabetes, action to 147, 148
Convergence dampening 244
Cornea 125
in smile, biomechanical properties of 5
Corneal abscess 107f
Corneal cap precision in smile 7
Corneal edema 120, 121f
Corneal endothelial deposits 43
Corneal perforation 16
Corneal scar 16
Corneal surface, anterior 4f
Corneal tensile properties 5f
Corneal transplant 14
Cortical vein 214f
abnormal 213f
reflux to 214f
Corticosteroids 14, 53, 280
Cultivated limbal epithelial transplantation 26
Cutaneous pathergy 263
Cyclosporin A 18
Cyclosporine 53
Cystadrops 259
Cystagon 259
Cystaran 259
Cystinosis 255, 257f
Cystoid edema 144f
Cystoid macular edema 53, 57, 281
Cytomegalovirus retinitis 62
Cytotoxic agents 280
D
Darpin 168
Demographics 170
Dendritic ulcer 17f
Dexamethasone 104, 154, 155
Diabetes
complication 147
epidemiology of 147
control trial 147
intervention, epidemiology of 147
mellitus 14
Diabetic eye disease 140f
Diabetic macular edema 57, 139, 141, 142, 145, 146, 149, 156
classification of 142, 143
diffuse 144f
pathogenesis of 141f
Diabetic retinopathy 139, 156
disease severity scale 141
study, early treatment 139
Diacylglycerol 141
Diencephalon 243
Diet 189
Diquafosol 24, 26
Disciform keratitis 17, 19f
Disk edema 43
DNA
replication 60
synthesis 17
viruses 12
DNA-dependent RNA polymerase 42
Drainage systems 24
Drugs 189
Dry eye 4
advances in diagnosis of 24
disease, management of 24t
novel therapies for 25
DSA machine 206
Dural arteriovenous fistula 208, 212
E
Eales’ disease 36
Eccentric gaze nystagmus 230, 231
Eccentric horizontal null position 250
Eculizumab 161, 162
Eczema, severe 14f
Electrophysiology 277
Embryonic organogenesis 255
Emerging therapeutic options 161, 165
Emixustat 164
Encapsulated cell technology 165, 167
Endocrine 256
Endogenous bacterial 136
Endophthalmitis 36, 107f, 126, 127, 135
after intravitreal avastin 111f
chronic 109
classification of 100t
epidemiology of postoperative 126
legal issues to 115
postoperative 99, 127
types of 135t
vitrectomy study 127
with corneal involvement 111f
Endothelial keratitis 13, 19
Endothelial keratoplasty, after 16f
Endothelin 141
Endovascular intervention 206208, 212, 216, 223
Endovascular therapy in neuro-ophthalmic lesions 208
End-tuberculosis strategy 32
Epiretinal membrane 272f
Epithelial keratitis 16, 19
Epstein Barr virus 46
Erythema nodosum 264
Erythrocyte sedimentation rate 206
Esotropia 195
Ethambutol 42
European league against rheumatism 279
Excited dimer 1
Exotropia 195
Extraocular muscles 125
Extrascleral extension 201
Extremely drug resistant 43
Eye 28f, 68f
disease study, age-related 161, 163
dressings 133
drops 133
infection 125
movement
abnormalities, classification of 230
recording 238
normal 76f
pathogenesis involving 258
perimetry, left 210f, 211f
report
both 71f
single 70f
Eyelid 47, 125
eversion of lower 223f
F
Facial vein 219f
Femtosecond laser technology 1
Femtosecond-laser in situ keratomileusis 4, 6
Fenretinide 164
Fever primes retina 186
Fibrotic sequelae 171
Fine needle aspiration cytology 40f
Fluocinolone 155
Fluocinolone acetonide 57
Fluorescein angiography 143, 171
Focal macular edema 143, 143f
Focal therapy 197, 200
Food and drug administration 57
Fovea 43
Foveal avascular zone 144
Foveation domain, longest 245
Fundus autofluorescence 39, 40f, 162, 173
Fundus examination 119
Fundus fluorescein angiography 39, 145, 176f
role of 145t
Fungal endophthalmitis 108, 108f
Fusarium species 129
Fusion maldevelopment nystagmus syndrome 231, 237239
G
Gallium 52
Ganglion cell 78
complex 78, 78f, 86f
layer 78
Gastrointestinal disease 266
Gene therapy 260
Genetic 180
factors 275
Genexpert omni 43
Genital ulcers 263, 265
Genitourinary involvement 266
Gentamicin 104
Geographic atrophy 160
Ghost vessels 273f
Glaucoma probability score 73f
Glaucoma 51, 54
diagnosis of 80
future developments in 93
management 65
probability score 72, 73, 73t
secondary 54
Glaucomatous damage, early 88f
Glucocorticoid family 57
Glycemic control 147
Gonads 257
Gonioscopy 120
Gram-negative bacteria 100
Granuloma 49f
Granulomatous uveitis, anterior 48f
Graphic recording of nystagmus 235, 237f
Growth retardation 256
Guglielmi detachable coils 207
H
Hand-washing technique 130
Head posture 244
abnormal 237, 238f
Heerfordt's syndrome 47
Heidelberg engineering 69
Heidelberg retina tomograph 65, 69, 72
Helicobacter pylori 46
Hematoma, extradural 218
Hemorrhage 171
Hemorrhagic peds, large 174
Hemorrhagic retinopathy 48
Hepatitis C 46
Herpes simplex keratitis, classification of 13t
Herpes simplex virus 1113, 15, 20, 46
disease 12, 14
infection 11
keratitis 13, 15, 19
prevention of recurrent 20
risk factors for 14t
type of 13
vaccination 20
Herpetic endotheliitis 18
Herpetic eye disease 11
study 11, 18
Herpetic retinochoroiditis 36
Herpetic uveitis 51
Hertle's criteria 243
Hilar lymphadenopathy
bilateral 50, 51f
chest X-ray-bilateral 50
HIV infection 14
Human central nervous system stem cells 165
Hyperdense serpiginous, abnormal 213f
Hyperglycemia, chronic 139
Hypertrophied feeding artery 226f
Hypopyon uveitis 43
I
Idiopathic intracranial hypertension 208, 211
Iluvien 154
Immune stressors 14
Immunity, altered 14
Immunosuppressive agents 280
Improvement in visual fields 211f
Incision lenticule extraction, small 2
Indocyanine green angiography 39, 171, 277
Induced pluripotent stem cells 165
Infantile nystagmus
diagnostic criteria of 232t
syndrome 231
Infection in ocular surgery, control of 125
Inflammatory cells, pearls of 270f
Inflammatory neovascular membrane 51
Inflammatory vitreous exudates 43
Intense pulsed light therapy 24
Intercellular adhesion molecule-1 5
Interdigitation zone 190
Inter-eye symmetry 68
Interferon- gamma release assays 36, 37, 41
Interferon-G 33
Interleukin 33, 275
International diagnosis of sarcoidosis 50t
Intra-arterial chemotherapy 198, 199f
Intracranial dural arteriovenous fistula 212
Intraocular
cataract surgery, progress in 125
fluids 118
lenses 119, 189
lymphoma, primary 51
pressure 39, 40, 58, 86, 120, 121
raised in 47
retinoblastoma 195t
tuberculosis 32, 37t
classification of 41t
Intraretinal microvascular abnormality 142
Intravenous chemotherapy 197
Intravitreal 61
antibiotics 103f
anti-VEGFs 53
chemotherapy 199
clindamycin 62
corticosteroid 154t
dexamethasone 58
implants 58
drugs in endophthalmitis 104t
fluocinolone acetonide 58
ganciclovir 62
immunosuppressives 60
injections 56, 57, 151, 167
methotrexate 60
nonsteroidal anti-inflammatory drug 59
steroids 151
therapeutics in
infectious uveitis 62
noninfectious uveitis 56
uveitis, advances in 56
therapy 150
current 155t
triamcinolone acetonide 56, 57
vancomycin 104f
Intravitreous triamcinolone acetonide 57, 155
Iris 47
mass 47
Isoniazid 42
J
Joint involvement 267
Joubert syndrome 244
Juvenile rheumatoid arthritis in children 51
K
Keratitis, type of 19
Keratoconjunctivitis sicca 47
Keratolimbal allograft 26
Keratoprosthesis surgery 26, 27
Klebsiella pneumoniae 128
L
Lacrimal gland involvement 47
Lacrimal secretory 24
Lampalizumab 161
Laser flare photometry 277
Laser in situ keratomileusis 1, 2, 8, 14, 15
Laser refractive surgery of cornea 1
Laser source 93
Laser therapy 148
Latent nystagmus 237
Leber's congenital amaurosis 244
Leprosy 36
Leukocyte cystine levels 259
Lifitegrast 24
Light intensity 7
Light pollution 190
Light sensitivity 244
Light-emitting diodes 188
Limbal stem cell deficiency 26, 27, 27f, 28
management of 26, 26t
Lipid control 147
Lipiflow 24
Lipopolysaccharide 113
Liver enzyme tests, abnormal 50
Lofgren's syndrome, acute 47
Low vision 244
Lung 46
LVP Keratoprosthesis 26
Lyme disease 51
Lymphocyte function-associated antigen 1 25
Lypoxygenase 141
M
Macular degeneration, age-related 57, 160, 170, 174, 189
Macular edema 139, 154, 281f
diffuse 143
type of 146, 146f
Macular ischemia 144, 144f, 269f
Macular phototoxicity 185
acute 189
chronic 189
diagnosis of 189
Macular scar 273f
Macular swelling, causes of 145
Malignant melanoma lymphoma 36
Mantoux test 36, 37
Matrix metalloproteinase-9 24, 25
Mediastinal lymph nodes 46
Medications 119
Meibomian gland dysfunction 26
Meibomian glands 24
Meningeal artery, left middle 213f
Mesencephalon 243
Metaherpetic ulcer 16f
Metastatic disease 195
Metastatic tumor 36
Methotrexate 53
Microaneurysm 149
Microperimetry 146
Middle cerebral artery 225
Moderate myopia 3f
Moorfield's regression analysis 71, 73, 73t
Multicenter uveitis steroid treatment 58
Multidrug resistance TB 43
Multifocal chorioretinal lesions 48f
Multifocal choroiditis 36, 51
Multifocal placoid pigment epitheliopathy, acute posterior 36, 48
Multifocal serpiginoid choroiditis 40
Multiple lymph nodes 52f
Multiple sclerosis 51
Multi-resistant Staphylococcus aureus 134
Mutton fat keratic precipitates 47
MYC mutation 193
Mycobacterium tuberculosis 32, 36, 37, 46, 274
Mycophenolate mofetil 53
Myoclonic triangle 243
Myopathy 256
Myopia, changes in high 3f
N
Natural killer 275
Necrotizing keratitis 17
Needle-stick injury 130
Negative mantoux test 53
Negative tuberculin test 50
Nephropathic cystinosis 258f
Nerve fiber indicator 66, 68
Nerve fiber layer 78
Nerve growth factor 5
Neuro-Behçet's disease 263, 266
Neurology 257
Neuro-ophthalmic involvement 266
Neuroretinal rim 78
Neuroretinitis 35
Neurotrophic keratopathy 16
New anti-VEGF agents 166
New anti-VEGF drugs 165
Newer intravitreal antibiotics 113
Nitric oxide 141
Nodular periphlebitis 48
Nodule in trabecular meshwork 47
Nongranulomatous anterior uveitis 47
Non-infectious uveitis 56
Nonocular manifestations 264
Non-proliferative diabetic retinopathy 139, 142, 156
Nucleic acid amplification tests 38
Nystagmus 230, 239t, 242t, 244, 244t
acuity function 240
expanded 239
classification of 239t
interpretation of 236I
pathophysiology of 235
pharmacological treatment of 245
surgical treatment of 250
syndrome 234f
types of 246t
pathological 231t
O
Occipital arteriovenous malformation 224
Occipital artery 213f
Occult chroidal neovascular membrane 171
Ocular complications 51
management of 280
Ocular conditions, abnormal 244t
Ocular disease 263
Ocular histopathology 276
Ocular HSV infection 12
Ocular hypertension treatment study 69
Ocular manifestations of Behçet's disease 267
Ocular media 188
Ocular recurrences 20
Ocular sarcoidosis 45, 47, 50
diagnosis of 51
prognosis of 54
Ocular surface
disease 4
disorders 29
management of 24, 28
treatment of 28t
squamous neoplasia 28
Ocular tissues 32
Oculocutaneous albinism 234f
Ophthalmic artery 208
infusion, selective 199
Ophthalmic disorders 206
Ophthalmic practice 132
Ophthalmic treatment 259
Ophthalmic vein
left superior 219f
superior 218, 219f, 221f, 222f
Ophthalmoscopic features 171
Optic atrophy 43
Optic disc 71
edema 51
granuloma 40
neovascularization 51, 281
size 71
Optic nerve 276
head 66, 77f, 78f
analysis 77
sarcoid granuloma 49f
involvement 36
Optic neuritis 43
Optic neuropathy 40
Optic OCT, adaptive 94
Optical coherence tomography 39, 65, 73, 74, 85, 145, 162, 171, 172, 239
angiograms 95
angiography 95, 146, 173
role of 146t
Optical management of nystagmus 244, 244t
Optokinetic nystagmus 230
Oral
acyclovir 18
medication 148
steroids 14f
ulcers 263
Orbital retinoblastoma 202f
Organ transplant recipients 14
Oscillopsia 244
Ozurdex 154
P
Pain 120
Palsy 263
Panophthalmitis 36
Panretinal photocoagulation 156
Panuveitis 36
Pars plana vitrectomy 156
Pathergy test 267
Pazopanib 167
Periarteritis nodosa 278
Periocular Subtenon's chemotherapy 198
Periodic alternating nystagmus 238
Peripapillary atrophy 89f
Peripapillary nerve fiber layers 77f
Peripapillary splinter hemorrhages 43
Periphlebitis, acute 269
Peroxisomal disorders 244
Persistent fetal vasculature 196
Photic injury 185
Photodynamic therapy 175
Photomechanical injury 185
Photorefractive keratectomy 1, 5
Photothermal injuries 185
Phototoxic injury 185
Phototoxicity 186
Pigment epithelial
derived factors 149
detachments 172
Plaque brachytherapy 200
Plexiform layer, inner 78
Polarization sensitive optical coherence tomography 94
Polylactic acid-co-glycolic acid 59
Polypoidal choroidal
neovascularisation 172
vasculopathy 170, 174
management of 175
Post-cataract
acute 135
chronic 135
surgery 104
Posterior communicating artery 208, 224f
aneurysm 223
Prednisolone acetate 122
Pre-perimetric glaucoma 87f
Presumed ocular sarcoidosis 50
Primitive neuroectodermal tumors 194
Probable ocular sarcoidosis 50
Proliferative diabetic retinopathy 139, 156
Prominent posterior hyaloids 270f
Prophylaxis 112, 129
Propionibacterium acnes 46, 109
Protein kinase C 140, 141
Pseudomonas
aeruginosa 129
strains 113
endophthalmitis 114
Pulmonary function test 52
Pulmonary involvement 267
Pulmonary sarcoidosis 46
Punctate inner choroidopathy 36
Pupil 121
Pupillary nodules 47
Pyrazinamide 42
R
Radical vitrectomy with silicone oil 107f
Radiotherapy, external beam 200
Ranibizumab 150, 155
Rapamycin 162
RB1 gene 193
Reactive oxygen species 139
Rebamipide 24, 25
Recurrent keratitis 16
Recurrent polypoidal choroidal vasculo-pathy 180
Refractive error 244
Refractive lenticule extraction 2, 7
Refractive procedures, effect of 4f
Regenerative stem cell therapies 161
Relex smile 5, 7, 8
Renal 256
Renal biopsy, stain of 258f
Renal manifestations, extra 256
Rennin angiotensin system 141
Restore 150
Retina 276
Retinal detachment 51
Retinal disc neovascularization 51, 281
Retinal disease 189
Retinal edema pigmentary changes 43
Retinal ganglion cells 65
Retinal hemorrhages 268f, 269f
Retinal ischemia 51, 269f
Retinal laser therapy, selective 150
Retinal macroaneurysm 48
Retinal nerve fiber
bundles 94
layer 65, 67, 72, 75, 77
analysis 75
curvature 73
thickness 66, 80
Retinal perivasculitis 40
Retinal pigment epithelial 94, 161, 273f
changes 271f
Retinal pigment epithelium mottling 186
Retinal vasculitis 35
Retinitis 270
Retinoblastoma 36, 193, 196f, 202
advanced 199f
gene 193
staging system for 195t
Retinovascular 143
Reverse staining pattern 16
Rifampicin 42
Right eye 202f
perimetry 210f, 211f
Right ophthalmic segment aneurysm 217f
Right palpebral fissure, obliteration of 223f
Right transverse sinus 209f
Right vertebral artery 226f
RNA transcription 60
Rostaglandin analogs 14
S
Sarcoid nodule 49f
Sarcoidosis 36, 45, 47t, 50, 278t
clinical signs of 50
diagnosis of 51t
posterior segment in 48t
prevalence of 45
Scanning laser polarimetry 65, 81
Scleral buckling, posterior 209f
Segment invasion, anterior 201
Segmental periphlebitis 48
Serous exudation 171
Serous retinal detachment 176
Serpiginous choroiditis 36
Serpiginous-like choroiditis 34
Serum ace levels 50
Sexual transmission 262
Sigmoid sinus 209f
Simple limbal epithelial transplantation 26, 27
Sirolimus 161, 162
Skin
disease 263
lesions 264
Slit lamp
biomicroscopy 132
examination 119
Smile 1, 46, 8
advantages of 4
patients 4
surgery, enhancements after 7
Snellen visual acuity 188f
Snowballs 48
Spasmus nutans syndrome 234, 235f
Spectacles 133
Spectral domain optical coherence tomography 190
Staphylococcus aureus 100, 128
Staphylococcus epidermidis 129
Staphylococcus infection, cycle of 128f
Stem cell therapy 165
Stereometric parameters 71
Steroids 165, 166
intensive 102f
response to 120
Stevens-Johnson syndrome 28
Stop-TB strategy 32
Strabismus 230
Streptococcus species 128
Strokes 263
Stromal keratitis 13, 17, 19
Subretinal abscess 35
Subretinal fluid 161
Subretinal haemorrhage, management of 178
Subretinal scarring 273f
Subthreshold micropulse laser 149
Sunlight 186
Superior petrosal sinus 221f
Supplements 189
Surgery, benefits of 248t
Surgical instruments 131t
Sustained drug-delivery devices 165, 167
Sustained release implants 151
Sustained release intravitreal implants 154
Sympathetic ophthalmia 36, 51
Synechiae, broad posterior 40
Syphilis 36, 51
Systemic immunosuppression 14
Systemic intravenous chemotherapy 197, 198f
Systemic lupus erythematosus 278
Systemic sarcoidosis 46
T
T cell ratio 46
Taut attached posterior hyaloid 145
T-cell predominance 276
Tear inflammatory mediators in smile 5
Tear meniscus height 4
Temporal arachnoid cyst 225f
Tent-shaped peripheral anterior synechiae 47
Thermal laser 175
Thiazolidinediones 141
Third generation laser refractive surgery 2
Thrombophlebitis 263
Time-domain technology 74
Tissue
biopsy 53
plasminogen activator 178
Tonometer prisms 132
Toxic anterior segment syndrome 100, 117
Toxic endothelial cell destruction syndrome 117
Toxocara species 129
Toxoplasma gondii 129
Toxoplasmosis 36, 51
Tractional macular edema 146f
Tractional retinal detachment 156
Traimcinolone 155
Transbronchial lung biopsy 53
Transpupillary thermotherapy 200
Transverse sinus 214f
junction of right 209f
left 213f
Triamcinolone acetonide 57, 151
TSNIT average 67
TSNIT standard deviation 68
TSNIT symmetry graph 67
Tubercular anterior uveitis 34f
Tubercular retinal vasculitis 35f
Tuberculin skin test 36, 37, 41
Tuberculoma 34
Tuberculosis 33, 33f, 41, 51
diagnosis of 36t
Tumor necrosis factor alpha 5, 33, 275
U
Umbilical cord serum 29
United Kingdom Prospective Diabetes Study 147
Untreated retinoblastoma 197
Uvea 276
Uveitis 33, 56, 267, 273f
anterior 33, 270f
chronic posterior 273f
compatible 50
in immunocompetent 41
intermediate 33, 47
posterior 33, 271f
severe acute anterior 43
treatment, double-masked 61
V
Valacyclovir 20
Vancomycin 104
Vascular endothelial growth factor 58, 59, 141
expression 56
injections 161f
threshold 156
Vascular network, branching 170, 172
Vascular occlusions 51, 265
Vasculitis 263, 265
Venous sinus 214f
Vermis, anterior 243
Vernal keratoconjunctivitis 28
Vertebral artery 207
left 213f
Vestibular nucleus, superior 243
Vestibular nystagmus 230
Video nystagmography 239
Viscoelastic residues 118
Vision 120
in Behçet's disease 282
in left eye, blurred 34f
loss, evaluate unexplained 145, 146
Visual acuity
best corrected 101
corrected distance 7
reduction in 270f
Visual cycle modifying agents 161, 164
Visual fields 211f
Vitrectomy 155
Vitreo macular traction 146
Vitreous 120, 270f
cytology 52
hemorrhage 51, 281
infiltrates 35
Vitritis 35, 269, 269f
Vogt-Koyanagi-Harada
disease 36
syndrome 51
Voriconazole 104
W
Wegener's granulomatosis 278
Welding arc 186
White reflex 196f
Z
Zimura 161, 162
×
Chapter Notes

Save Clear


SMILE vs LASIKChapter 1

Jorge L Alio
Mohamed El Bahrawy
 
RECENT EVOLUTION OF LASER REFRACTIVE SURGERY OF THE CORNEA
The concepts of modern refractive surgery witnessed its breakthrough when Professor Jose I Barraquer described in 1949 his coined technique of keratomileusis, setting the foundation for all following innovation in this field. The name excimer laser came as an abbreviation of “excited dimer”, introduced by the Russian, Nikolay Basov, in 1970 using a xenon dimer gas. Few years later, the argon-fluoride excimer laser was developed and was first tried on an organic tissue by IBM scientists. The introduction of excimer laser to be used in the human eye was done by Stephen Trokel as a precise and safe tool of corneal shaping, these concepts later defined the refractive techniques widely used now, when Marguerite McDonald under the supervision of Steve Kaufmann, performed the most commonly used epithelium removal technique photorefractive keratectomy (PRK). Peyman, presented the first patency of using excimer laser as a corneal refractive tool, and it was accepted in June 1989 (personal correspondence Gholam Peyman). Following Ioannis Pallikaris, among others, introduced the most widely used and commonly accepted technique of laser in situ keratomileusis (LASIK) in 1990.1 Laser refractive surgery has been performed for decades, and there have been tremendous advancements in terms of technique and technology, making it increasingly precise and highly predictable.2 LASIK is currently the most common laser refractive procedure for the treatment of myopia—its advantages include early postoperative improvement in visual acuity and minimal postoperative patient discomfort. Although LASIK patients report 95% satisfaction, a spectrum of complicated side effects can negatively impact results.3
Femtosecond laser technology was first developed by Dr Kurtz at the University of Michigan in the early 1990s,4 and was rapidly adopted in the surgical field of ophthalmology. Femtosecond lasers emit light pulses of short duration (10−15s) at 1053 nm wavelength that cause photodisruption of the tissue with minimum collateral damage.5 The femtosecond laser has revolutionized corneal and refractive surgery with respect to its increased safety, precision, and predictability over traditional microkeratomes. Advantages of bladeless femtosecond assisted LASIK (FS-LASIK) over conventional microkeratome assisted LASIK (MK-LASIK) include reduced dry eye symptomatology, reduced risk of flap button hole or free cap formation.6,72
Ever since femtosecond lasers were first introduced into refractive surgery, the ultimate goal has been to create an intrastromal lenticule that can then be manually removed as a single piece thereby circumventing the need for incremental photoablation by an excimer laser. A precursor to modern refractive lenticule extraction (ReLEx) was first described in 1996 using a picosecond laser to generate an intrastromal lenticule that was removed manually after lifting the flap,8,9 however, significant manual dissection was required leading to an irregular surface. The switch to femtosecond improved the precision10 and studies were performed in rabbit eyes in 199811 and in partially sighted eyes in 200312 but these initial studies were not followed up with further clinical trials. Following the introduction of the VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany) in 2007,13 the intrastromal lenticule method was reintroduced in a procedure called femtosecond lenticule extraction (FLEx). The 6-month results of the first 10 fully seeing eyes treated were published in 200814 and results of a larger population have since been reported.15,16 The refractive results were similar to those observed in LASIK, but visual recovery time was longer due to the lack of optimization in energy parameters and scan modes; further refinements have led to much improved visual recovery times.17 Following the successful implementation of FLEx, a new procedure called small incision lenticule extraction (SMILE) was developed. This procedure involves passing a dissector through a small 2–3 mm incision to separate the lenticular interfaces and allow the lenticule to be removed, thus eliminating the need to create a flap. The SMILE procedure is now gaining popularity following the results of the first prospective trials.1829
 
Small Incision Lenticule Extraction (SMILE) Outcome
Since, the development of the SMILE technique, the exciting new concept of the flapless nature of the technology, namely the 3rd generation laser refractive surgery, has driven many authors to approach it and report the results of SMILE outcomes alone or in comparison with LASIK.
In a study we conducted, we compared the outcomes of a matched case of SMILE versus 6th generation excimer laser LASIK patient, where the cases were matched by age, gender and spherical equivalent. In the SMILE group; 50% females, 34 years (23:49), −4.59 diopters (–2.125:–8.37), the LASIK group; matching SMILE/FLEx cases: of same gender, age (±1 year), spherical equivalent (±0.5 D). The study included 16 eyes in each group, and we reported both SMILE and LASIK had comparable results in terms of safety, efficacy and predictability, in follow up of 6 months duration (Table 1.1).
TABLE 1.1   Refractive outcome of comparative study between SMILE and LASIK
Comparison
SMILE
FS-LASIK
20/20 or more
93.75%
92.18%
20/25 or more
100%
96.87%
20/40 or more
100%
100%
Efficacy
No loss of lines
96.87%
93.43%
Lost more than 2 lines
0%
0%
Gained lines
18.75% (1 line)
18.64% (1–3 lines)
Predictability
% of cases ± 0.5 D
84.43%
86.25%
% of cases ± 1.0 D
100%
100%
3
zoom view
Figs 1.1A and B: Topographical changes in moderate myopia
zoom view
Figs 1.2A and B: Topographical changes in high myopia
4Many other authors reported similar outcomes, still with a disadvantage of slower refractive recovery in SMILE patients, which is currently witnessing significant improvements due to the development of different energy and spot spacing setting.17,21 Kim et al. reported that age may be a predictor that influenced visual outcome, as outcomes were better in younger patients of his study sample but its effect appeared clinically insignificant.22 SMILE surgery was effective and safe in correcting low to moderate astigmatism, and stable refractive outcomes were observed at the long-term follow-up. The preoperative cylinder ranged from −2.75 D to −0.25 D (average of −0.90 ± 0.68 D), and the mean postoperative cylinder values were −0.24 ± 0.29 D, −0.24 ± 0.29 D, and −0.20 ± 0.27 D at 1 month, 6 months, and 12 months, respectively.23
On the other side topographic changes and barometric changes were significantly lower in SMILE patients compared with LASIK patients whether in mild to moderate myopia or high myopia as reported by results of our study (Figs 1.1 and 1.2).
 
Advantages of SMILE in Cases of Dry Eye and Ocular Surface Disease
The flapless nature of SMILE will preserve the important anterior corneal phase, this will preserve the natural integrity of corneal nerves, which will significantly influence the ocular surface and tear film stability (Fig. 1.3).
Central corneal sensitivity exhibited a small decrease and a faster recovery after the SMILE procedure compared to FS-LASIK during the first three postoperative months. Corneal sensitivity after SMILE and FS-LASIK was similar at 6 months after surgery.24 Qiu et al. in a longitudinal retrospective study studied ninety-seven consecutive patients (193 eyes) who underwent SMILE for myopia. Parameters evaluated included: subjective dry eye symptoms (dryness, foreign body sensation and photophobia), tear film breakup time (TBUT), Schirmer's test without anesthesia, tear meniscus height (TMH) and corneal fluorescein staining. Each parameter was evaluated before, and subsequently at 1 day, 1 week, 1 month and 3 month after surgery. The results showed that compared with preoperative data, dryness was noted to be significantly increased at 1 week and 1 month postoperatively (P <0.01). Symptoms of photophobia and foreign body sensation demonstrated significant differences at 1 day and 1 week as compared with preoperative scores respectively (P <0.01). These values were decreased at 1 and 3 month postsurgery (P >0.05). Conversely the corneal staining scores were higher than the preoperative data at 1 day, 1 week and 1 month (P <0.01), but were close to the preoperative level at 3 months postoperatively. There was a significant decrease in TMH at 1 week and 1 month (P <0.01), but the value was close to the preoperative level at 3 months postoperatively (P = 0.16).
zoom view
Fig. 1.3: Effect of different refractive procedures on the anterior corneal surface
5The examination outcomes of ST were significantly increased at 1 day then reduced at 1 week after surgery (P <0.01). Each value subsequently returned to the baseline value at 1 and 3 months (P >0.05). TBUT was significantly decreased at all postoperative time points (P < 0.01). It is reported that SMILE resulted in mild dry eye symptoms, tear film instability and ocular surface damages; however, these complications can recover in a short period of time.25 This was confirmed when compared with FS assisted LASIK by Li et al. as he reported that SMILE surgeries resulted in a short-term increase in dry eye symptoms, tear film instability, and loss of corneal sensitivity. Furthermore, SMILE surgeries have superiority over femto-LASIK in lower risk of postoperative corneal staining and less reduction of corneal sensation.26
 
Tear Inflammatory Mediators in SMILE
In a study by Gao et al. Tears were collected and analyzed for interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), nerve growth factor (NGF) and intercellular adhesion molecule-1 (ICAM-1) levels using multiplex magnetic beads. All measurements were preformed preoperatively and 1 day, 1 week, 1 month and 3 months postoperatively. They reported that In the early postoperative period, ReLEx SMILE results in milder ocular surface changes than FS-LASIK. Furthermore, the tear inflammatory mediators IL-6 and NGF may play a crucial role in the ocular surface healing process following ReLEx smile and FS-LASIK.27 SMILE induces less keratocyte apoptosis, proliferation and inflammation compared with femtosecond laser LASIK.28
 
Biomechanical Properties of the Cornea in SMILE
Randleman et al. suggested that the cohesive tensile strength of the stroma is based on how the stromal lamellae are held together, which decreases from anterior to posterior within the central corneal region. Reinstein et al. used a mathematical model to predict that the postoperative tensile strength would be higher after SMILE than both LASIK and PRK, given the fact that the strongest anterior lamellar layer remains intact, enabling it to correct higher levels of myopia with a better safety profile. In our investigation, we studied biomechanical corneal properties by comparing targeted vs obtained radius of curvature (Fig. 1.4).
The mean values and standard deviation of the curvature change coefficient are: [(Paired T-test) SMILE: −1.77 ± 1.72 (%), FS-LASIK: −1.82 ± 3.76 (%)].
zoom view
Fig. 1.4: Mathematical model for calculation of corneal tensile properties
6
zoom view
Fig. 1.5: Results of biomechanical tensile changes in SMILE and FS-LASIK
zoom view
Fig. 1.6: Results of biomechanical tensile changes in SMILE and FS-LASIK
A good correlation for the linear fit: (Pearson Correlation) R = 0.95 for SMILE group R = 0.85 for FLEX group. There are not statistically significant differences (P>0.1) between two groups. However, the low standard deviation of the SMILE group demonstrates a better predictability for this technique (Figs 1.5 and 1.6).
Other study used Scheimpflug-based noncontact tonometer, concluded that no significant modifications in biomechanical properties were observed after SMILE so this procedure could induce only minimal transient alterations of corneal biomechanics.29 When correlating corneal biomechanical properties with the induced high-order aberrations. The preoperative CRF was significantly correlated with the induced 3rd–6th order HOAs and spherical aberration of the anterior surface and the total cornea after SMILE and FS-LASIK surgeries (P<0.05), postoperatively. The CRF was significantly correlated with the induced vertical coma of the anterior and posterior surfaces and the total cornea after SMILE surgery (P<0.05). There was a significant correlation between the CRF and the induced posterior corneal horizontal coma after FS-LASIK surgery (P = 0.013). This indicates that corneal biomechanics affect the surgically induced corneal 7HOAs after SMILE and FS-LASIK surgery, which may be meaningful for screening the patients preoperatively and optimizing the visual qualities postoperatively.30 On the other hand in high myopic patients, FS-LASIK demonstrated a greater increase in posterior corneal elevation than SMILE only at 12 months as well as a greater reduction of CRF than SMILE, but there were no significant difference between the two groups over time.31
 
Confocal Microscopy in SMILE
In confocal microscopy study, the mean backscattered light intensity (LI) at all measured depths and the maximum backscattered LI were higher in the SMILE group than the femto-LASIK group at all postoperative visits. LI differences at 1 week and 1 month and 3-month visits were statistically significant (P< 0,05). LI differences at 6 months were not statistically significant. There was no difference in the number of refractive particles at the flap interface between the groups at any visit. It may be concluded that SMILE results in increased backscattered LI in the anterior stroma when compared with femto-LASIK.32 The decrease in sub-basal nerve fiber density was less severe in the SMILE group than the FS-LASIK group in the first 3 months following the surgery. The sub-basal nerve density was correlated with central corneal sensitivity.33
 
Corneal Cap Precision in SMILE
There is a significant change in corneal deformation parameters following SMILE procedure. The changes may be caused predominantly by stromal lenticule extraction, while lenticule creation with femtosecond laser may not have an obvious effect on corneal deformation properties.34 A study conducted investigating the morphology of SMILE cap using anterior segment optical coherence tomography reported that corneal caps of SMILE are predictable with good reproducibility, regularity and uniformity. Cap morphology might have a mild effect on refractive outcomes in the early stage.35 and the predictability of cap thickness in SMILE surgery does not differ from the femto-LASIK flaps created using the same femtosecond laser platform.36
 
Enhancements after SMILE Surgery
One of the most important challenges facing SMILE technology is the enhancement methodology in postoperative refractive residuals. In a study enrolled 28 eyes 27 underwent the VisuMax® Circle pattern procedure for refractive enhancement, and 1 for residual lenticule extraction. In 100% of cases (28 eyes) the lifting of the flap was possible, as planned. In all cases of refractive enhancement (27 eyes) by LASIK, the exposure of the stromal bed was sufficient for the necessary excimer laser ablation. No eyes lost two or more Snellen lines of corrected distance visual acuity (CDVA) and no procedure or flap related complications or serious adverse events occurred. This initial case series demonstrates that VisuMax® Circle pattern is efficacious and a suitable method to create a corneal flap for enhancement, following small incision lenticule extraction.37
 
Innovative Indications of Laser Lenticular Extraction
  1. The technique of cryopreservation of corneal lenticules extracted after small incision refractive lenticule extraction (ReLEx SMILE) and initial results of8 femtosecond laser intrastromal lenticular implantation for hyperopia: The technique seems to be a safe method of long-term storage of refractive lenticules extracted after ReLEx SMILE for use in allogeneic human subjects. It may potentially be a safe and effective alternative to excimer laser ablation for hyperopia because of the low risks of regression, haze, flap-related complications, postoperative dry eye, and higher-order aberrations.38
  2. ReLEx SMILE Xtra, small-incision lenticule extraction with accelerated cross-linking; in patients with thin corneas and borderline topography: Based on the initial clinical outcome it appears that SMILE Xtra may be a safe and feasible modality to prevent corneal ectasia in susceptible individuals.39 Also this has been investigated in forme fruste keratoconus and irregular corneas, combined small-incision lenticule extraction and intrastromal corneal collagen cross-linking are a promising treatment option for patients for whom conventional laser refractive surgery is contraindicated.40
  3. Finally, A feasibility study reported that LASIK can be performed following lenticule re-implantation to create presbyopic monovision. The tissue responses elicited after performing LASIK on corneas that have undergone SMILE and subsequent lenticule re-implantation are similar to primary procedure.41
REFERENCES
  1. El Bahrawy M, Alió JL. Excimer laser 6th generation: state of the art and refractive surgical outcomes. Eye Vis (Lond). 2015;2:6.
  1. Alio J. Refractive surgery today: is there innovation or stagnation? Eye Vis (Lond). 2014;1:4.
  1. Alio JL, Muftuoglu O, Ortiz D, Pérez-Santonja JJ, Artola A, Ayala MJ, et al. Ten-year follow-up of laser in situ keratomileusis for high myopia. Am J Ophthalmol. 2008;145:46–54.
  1. Soong HK, Malta JB. Femtosecond lasers in ophthalmology. Am J Ophthalmol. 2009;147:189–97.
  1. Ratkay-Traub I, Ferincz IE, Juhasz T, Kurtz RM, Krueger RR. First clinical results with the femtosecond neodymium-glass laser in refractive surgery. J Refract Surg. 2003;19:94–103.
  1. Salomao MQ, Wilson SE. Femtosecond laser in laser in situ keratomileusis. J Cataract Refract Surg. 2010;36:1024–32.
  1. Morshirfar M, Gardiner JP, Schliesser JA, Espandar L, Feiz V, Mifflin MD, et al. Laser in situ keratomileusis flap complications using mechanical microkeratome versus femtosecond laser: retrospective comparison. J Cataract Refract Surg. 2010;36:1925–33.
  1. Krueger RR, Juhasz T, Gualano A, Marchi V. The picosecond laser for nonmechanical laser in situ keratomileusis. J Refract Surg. 1998;14:467–69.
  1. Ito M, Quantock AJ, Malhan S, Schanzlin DJ, Krueger RR. Picosecond laser in situ keratomileusis with a 1053-nm Nd:YLF laser. J Refract Surg. 1996;12:721–28.
  1. Kurtz RM, Horvath C, Liu HH, Krueger RR, Juhasz T. Lamellar refractive surgery with scanned intrastromal picosecond and femtosecond laser pulses in animal eyes. J Refract Surg. 1998;14:541–8.
  1. Heisterkamp A, Mamom T, Kermani O, Drommer W, Welling H, Ertmer W, et al. Intrastromal refractive surgery with ultrashort laser pulses: in vivo study on the rabbit eye. Graefes Arch Clin Exp Ophthalmol. 2003;241:511–7.
  1. Ratkay-Traub I, Ferincz IE, Juhasz T, Kurtz RM, Krueger RR. First clinical results with the femtosecond neodynium-glass laser in refractive surgery. J Refract Surg. 2003;19:94–103.
  1. Reinstein DZ, Archer TJ, Gobbe M, Johnson N. Accuracy and reproducibility of Artemis central flap thickness and visual outcomes of LASIK with the Carl zeiss meditec VisuMax femtosecond laser and MEL 80 excimer laser platforms. J Refract Surg. 2010;26:107–19.
  1. Sekundo W, Kunert K, Russmann C, Gille A, Bissmann W, Stobrawa G, et al. First efficacy and safety study of femtosecond lenticule extraction for the correction of myopia: six-month results. J Cataract Refract Surg. 2008;34:1513–20.
  1. Blum M, Kunert KS, Engelbrecht C, Dawczynski J, Sekundo W. Femtosecond lenticule extraction (FLEx)—results after 12 months in myopic astigmatism. Klin Monbl Augenheilkd. 2010;227:961–5.
  1. Vestergaard A, Ivarsen A, Asp S, Hjortdal JØ. Femtosecond (FS) laser vision correction procedure for moderate to high myopia: a prospective study of ReLEx(®) flex and comparison with a retrospective study of FS-laser in situ keratomileusis. Acta Ophthalmol. 2013;91(4):355–62.
  1. Shah R, Shah S. Effect of scanning patterns on the results of femtosecond laser lenticule extraction refractive surgery. J Cataract Refract Surg. 2011;37:1636–47.
  1. Sekundo W, Kunert KS, Blum M. Small incision corneal refractive surgery using the small incision lenticule extraction (SMILE) procedure for the correction of myopia and myopic astigmatism: results of a 6 month prospective study. Br J Ophthalmol. 2011;95:335–9.
  1. Shah R, Shah S, Sengupta S. Results of small incision lenticule extraction: All-in-one femtosecond laser refractive surgery. J Cataract Refract Surg. 2011;37:127–37.
  1. Reinstein DZ, Archer TJ, Gobbe M, et al. Small incision lenticule extraction (SMILE) history, fundamentals of a new refractive surgery technique and clinical outcomes. Eye Vis (Lond). 2014;1:3.
  1. Vestergaard A, Ivarsen AR, Asp S, Hjortdal JO. Small-incision lenticule extraction for moderate to high myopia: predictability, safety, and patient satisfaction. J Cataract Refract Surg. 2012;38:2003–10.
  1. Kim JR, Hwang HB, Mun SJ, Chung YT, Kim HS, et al. Efficacy, predictability, and safety of small incision lenticule extraction: 6-months prospective cohort study. BMC Ophthalmol. 2014;14:117.
  1. Zhang J, Wang Y, Wu W, Xu L, Li X, Dou R, et al. Vector analysis of low to moderate astigmatism with small incision lenticule extraction (SMILE): results of a 1-year follow-up. BMC Ophthalmol. 2015;15:8.
  1. He M, Huang W, Zhong X, et al. Central corneal sensitivity after small incision lenticule extraction versus femtosecond laser-assisted LASIK for myopia: a meta-analysis of comparative studies. BMC Ophthalmol. 2015;15:141.
  1. Qiu PJ, Yang YB. Early changes to dry eye and ocular surface after small-incision lenticule extraction for myopia. Int J Ophthalmol. 2016;9(4):575–9.
  1. Li M, Zhao J, Shen Y, Li T, He L, et al. Comparison of dry eye and corneal sensitivity between small incision lenticule extraction and femtosecond LASIK for myopia. PLoS ONE. 2013;8:10.
  1. Gao S, Li S, Liu L, Wang Y, Ding H, et al. Early Changes in Ocular Surface and Tear Inflammatory Mediators after Small-Incision Lenticule Extraction and Femtosecond Laser-Assisted Laser In Situ Keratomileusis. PLoS ONE. 2014;9:9.
  1. Dong Z, Zhou X, Wu J, et al. Small incision lenticule extraction (SMILE) and femtosecond laser LASIK: comparison of corneal wound healing and inflammation. Br J Ophthalmol. 2014;98:263–9.
  1. Mastropasqua L, Calienno R, Lanzini M, et al. Evaluation of corneal biomechanical properties modification after small incision lenticule extraction using Scheimpflug-based noncontact tonometer. Biomed Res Int. 2014;2014:290619.
  1. Wang Y, Wu W. The Correlation Analysis between Corneal Biomechanical Properties and the Surgically Induced Corneal High-Order Aberrations after Small Incision Lenticule Extraction and Femtosecond Laser In Situ Keratomileusis. J Ophthalmol. 2015;2015:758196.
  1. Wang B, Zhang Z, Naidu RK, et al. Comparison of the change in posterior corneal elevation and corneal biomechanical parameters after small incision lenticule extraction and femtosecond laser-assisted LASIK for high myopia correction. Cont Lens Anterior Eye. 2016;39(3):191–6.
  1. Agca A, Ozgurhan EB, Yildirim Y, et al. Corneal backscatter analysis by in vivo confocal microscopy: fellow eye comparison of small incision lenticule extraction and femtosecond laser assisted LASIK. J Ophthalmol. 2014;2014:265012.
  1. Li M, Niu L, Qin B, et al. Confocal comparison of corneal reinnervation after small incision lenticule extraction (SMILE) and femtosecond laser in situ keratomileusis (FS-LASIK). PLoS One. 2013;8(12).
  1. Shen Y, Zhao J, Yao P, et al. Changes in corneal deformation parameters after lenticule creation and extraction during small incision lenticule extraction (SMILE) procedure. PLoS One. 2014;9(8):e103893.
  1. Zhao J, Yao P, Li M, et al. The morphology of corneal cap and its relation to refractive outcomes in femtosecond laser small incisionlenticule extraction (SMILE) with anterior segment optical coherence tomography observation. PLoS One. 2013;8(8).
  1. Ozgurhan EB, Agca A, Bozkurt E, et al. Accuracy and precision of cap thickness in small incision lenticule extraction. Clin Ophthalmol. 2013;7:923–6.
  1. Chansue E, Tanehsakdi M, Swasdibutra S, et al. Safety and efficacy of VisuMax® circle patterns for flap creation and enhancement following small incision lenticule extraction. Eye Vis (Lond). 2015;2:21.
  1. Ganesh S, Brar S, Rao PA. Cryopreservation of extracted corneal lenticules after small incision lenticule extraction for potential use in human subjects. Cornea. 2014;33(12):1355–62.
  1. Ganesh S, Brar S. Clinical outcomes of small incision lenticule extraction with accelerated cross-linking (ReLEx SMILE Xtra) in patients with thin corneas and borderline topography. J Ophthalmol. 2015;2015:263412.
  1. Graue-Hernandez EO, Pagano GL, Garcia-De la Rosa G, et al. Combined small-incision lenticule extraction and intrastromal corneal collagen crosslinking to treat mild keratoconus: Long-term follow-up. J Cataract Refract Surg. 2015;41(11):2524–32.
  1. Lim CH, Riau AK, Lwin NC, et al. LASIK following small incision lenticule extraction (SMILE) lenticule re-implantation: a feasibility study of anovel method for treatment of presbyopia. PLoS One. 2013;8(12):e83046.