The Differences of Depth Parameters of Deposits The Differences of Depth Parameters of Deposits Depending on the Morphology in Granular Corneal Depending on the Morphology in Granular Corneal

Dystrophy Type Dystrophy Type ⅡⅡ by Fourier Domain Optical Coherence by Fourier Domain Optical Coherence TomographyTomography

Jin Pyo Hong,MDJin Pyo Hong,MD11, Jae Lim Chung,MD, Jae Lim Chung,MD11, Jung Won , Jung Won

Park,MDPark,MD22, Tae-im Kim,MD,PhD, Tae-im Kim,MD,PhD11, Kyoung Yul , Kyoung Yul Seo,MD,PhDSeo,MD,PhD11, Eung Kweon Kim,MD,PhD, Eung Kweon Kim,MD,PhD11

11Corneal Dystrophy Research Institute, Department of Ophthalmology, College Corneal Dystrophy Research Institute, Department of Ophthalmology, College of Medicine, Yonsei University, Seoul, Koreaof Medicine, Yonsei University, Seoul, Korea22Daegu Yonsei Eye Clinic, Daegu, KoreaDaegu Yonsei Eye Clinic, Daegu, Korea

Authors have no financial interest

Purpose

Granular corneal dystrophy typeⅡ (GCDⅡ) Arg124His mutation in the Bigh-3 gene Histologic feature of hyaline granules and amyloid lattice lines Granular deposits as the earliest manifestation Lattice deposits as later presentation Diffuse haziness as getting older

Surgical treatment of GCDⅡ Phototherapeutic keratectomy(PTK) Penetrating keratoplasty(PKP) Lamellar keratoplasty(LKP)

The depth of different deposits according to the patterns Should be identified before surgery Critical to decide which treatment modalities Such as PTK, PKP, LKP

Purpose

Fourier domain optical coherence tomography, RTVue-100®(Optovue Inc, Fremont, CA) High speed, high resolution tomography scanning 5 μm depth resolution Layer by layer assessment 26,000 A scan/second 0.04 second of one B scan acquisition

Purpose of this study To evaluate the differences of depth parameters depending on morphology

of deposits using Fourier domain optical coherence tomography, RTVue-100®

Methods

Patients 54 patients were evaluated Heterozygous GCDⅡ by gene analysis No history of uveitis, glaucoma, other ocular surface disease, previous

operation

Methods Standardization of measuring CCT for RTVue-100® with ultrasonic pachymeter

• 20 normal subjects (40 eyes)• 13 GDCII patients (23 eyes)

3 Classifications of deposits detected by RTVue-100®• Granular, lattice, diffuse haziness

Recurrent deposit after refractive surgery Two points for each different deposits per one patient

Methods

Classification Type I – diffuse haziness Type II – granular deposits

• Type IIa – round granulated• Type IIb – round spiculated

Type III – lattice deposits• Type IIIa – spiculated lattice • Type IIIb – conventional lattice (with long branches)

Parameters Following parameters measured from Bowman’s layer perpendicularily

• Distance of upper surface from Bowman’s layer(USBL)• Distance of lower surface from Bowman’s layer(LSBL)• Thickness of deposits(TD)

LSBLTD

USBL

Bowman’s layer

Results

Standardization of measuring CCT for RTVue-100® with ultrasonic pachymeter

CCT RTVue Ultra sono p

Normal subjects(n=40)

526.3±26.7 525.6±26.2 0.149

GCDII patients(n=23)

528.6±35.5 522.5±35.1 0.295

p 0.723 0.655

Type I diffuse haziness (white arrow)

Results

Type IIa Round granulated (white arrow)

Type IIb Round

spiculated (white arrow)

Results

Type IIIa Spiculated lattice (white arrow)

Type IIIb Conventional

lattice (white arrow)

Results

Recurrent deposits after LASIK

Results

The various parameters of deposits

Diffuse haziness(n=58)

Granular deposits(n=59)

Lattice deposits(n=74)

P

USBL 0 0 65.4±48.0 <0.001

LSBL 47.7±10.2 91.3±39.5 313.3±71.4 <0.001

TD 47.7±10.2 91.3±39.5 246.2±71.9 <0.001

The differences of depth between granular deposits (Type IIa vs Type IIb)

Parameters of granular depositsP

Round granulated (n=45) Round spiculated (n=14)

USBL 0 0 -

LSBL 85.7±22.7 84.7±17.4 0.899

TD 85.7±22.7 84.7±17.4 0.899

Results

The differences of depth between two different shaped lattice trunks(Type IIIa vs Type IIIb)

Parameters of lattice trunksP

Spiculated lattice (n=14) Conventional lattice (n=45)

USBL 62.2±44.5 64.7±49.9 0.869

LSBL 305.7±56.8 321.9±80.3 0.475

TD 242.5±61.3 256.4±67.4 0.494

The differences of depth between trunks and limbs of lattice with long branches (Type IIIb)

Parameters of lattice(n=74)P

Trunks limbs

USBL 67.1±52.5 165.0±110.1 <0.0001

LSBL 321.9±80.3 289.4±117.2 0.208

TD 253.0±75.3 125.7±40.9 <0.0001

Parameters of recurrent deposits after LASIK (n=15)

Parameters mean±SD (min – max)

Mean depth of center of deposits 84.9±43.6 (22 – 191)

Mean maximum thickness 85.6±24.9 (47 – 125)

Mean minimum thickness 45.1±18.0 (22 – 85)

Conclusion

1st report investigating in vivo the depth of deposits depending on the morphology

Three deposits had three distinct depths Diffuse haziness at the superficial layer Granules at ant. stroma Lattice deposits at mid to post. Stroma

No differences of depth between two shaped lattice deposits Easily detected by RTVue-100® in case slit lamp examination

can not reveal the depth Most of all

Guide the treatment modality according to what the main pattern of deposits are in the visual axis, such as PTK, DLKP, PKP by in vivo measuring with RTVue-100®