OCULUS Pentacam Interpretation Manual Download

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113

Figure 136: Corneal Optical Densitometry display showing a clear cornea following

laser scar peel; cataract present

Figure 137: Slit lamp image showing a clear cornea following laser scar peel;

cataract present

15 Using Pentacam

technology to evaluate corneal

scars, planning and documenting surgery outcomes

Summary of Contents for Pentacam

Page 1: ...US Optikger te GmbH Postfach 35549 Wetzlar GERMANY Tel 49 641 2005 0 Fax 49 641 2005 295 E Mail export oculus de www oculus de OCULUS USA info oculususa com OCULUS Asia info oculus hk OCULUS Czechia o...

Page 2: ...LUS Optikger te GmbH OCULUS has been certified according to DIN EN ISO 13485 and therefore sets high quality standards in the development production quality assurance and servicing of its entire produ...

Page 3: ...in OD and OS 15 5 2 Form fruste keratoconus 18 6 Fast Screening Report as a first step in examining a patient and evaluating one s findings by Ina Conrad Hengerer MD 20 27 6 1 Case 1 Unilateral high a...

Page 4: ...ophy with glaucoma by Prof Renato Ambr sio Jr Marcela Q Salom o MD 76 11 5 Screening parameters by Prof Renato Ambr sio Jr 79 12 Belin Ambr sio Enhanced Ectasia Display 80 102 12 1 Why elevation is di...

Page 5: ...ication time on Pentacam Nucleus Staging PNS by Mehdi Shajari MD Wolfgang Mayer MD Prof Thomas Kohnen 141 142 19 1 Introduction 141 19 2 Case 1 Low PNS and low EPT 142 19 3 Case 2 High PNS and high EP...

Page 6: ...mileusis in situ by Prof Renato Ambr sio Jr 171 24 Scheimpflug and slit lamp images 173 178 24 1 Corneal dystrophy 173 24 2 Congenital anterior pyramid cataract 174 24 3 Posterior capsular cataract 17...

Page 7: ...impflug images in three dimensions with the dot matrix fine meshed in the centre due to the rotation It takes a maximum of 2 seconds to generate a complete image of the anterior eye segment Any eye mo...

Page 8: ...reby taking this effect into account B Inclusion of anterior posterior surface By convention most keratometers use the refractive index of 1 3375 when calculating the dioptric power of the anterior ra...

Page 9: ...he front and back surface of the cornea however D Location of the principal planes Calculation of corneal power by ray tracing involves sending parallel light through the cornea It must take into acco...

Page 10: ...g to Snell s law of refraction assuming a refractive index of 1 3375 to convert curvature into refractive power Figure 2 This is a map that other Placido topographers also may show because it only con...

Page 11: ...r 1 336 as well as the sagittal curvature of each These results are aggregated The True Net Power map thus takes effects A and B into account The underlying equation is Figure 4 True Net Power map cal...

Page 12: ...map Its output is therefore also referred to as Equivalent Keratometer Readings EKR It calculates power according to Snell s law using the refractive indices of corneal tissue and aqueous humour and a...

Page 13: ...ncipal planes due to corneal thickness In this way the map takes effects A B C and D into account Its results are more realistic than any other but they will deviate from normal sagittal SimK values s...

Page 14: ...intended to discourage you from using other maps and settings that you may have found to work best for you 4 1 Recommended settings When working through the following chapters it is advisable to cons...

Page 15: ...3D pIOL Simulation Software and Aging Prediction prior to iris fixated pIOL implantation available in the Pentacam HR only Calculate the required pIOL power using the implanted calculator Use the dat...

Page 16: ...lmology Assessment of Corneal Optical Quality for Premium IOLs with Pentacam Highlights of Ophthalmology Vol 39 N 4 2011 Zernike Analysis to determine the amount HOA and LOA ACD manual horizontal whit...

Page 17: ...and numbers The topographic map Figure 8 shows the left and right eye but gives no unequivocal statement if it is a keratoconus or not The right eye seems to be fine The left eye is a little steeper T...

Page 18: ...posterior surface indicates this cornea as a suspicious cornea Both sides show an inferior position of the cone with suspicious elevations suspicious elevation Figure 9 4 Maps Selectable showing kerat...

Page 19: ...more than 30 m Note that the position of the thinning in the pachymetry map and the highest spot on the elevation map are exactly at the same position This is an excellent example to document that top...

Page 20: ...50 m The anterior and posterior elevation revealed a slightly decentered apex This had led to a false positive inferior steepening on the curvature map Custom LASIK was performed without incident Figu...

Page 21: ...e showing a form fruste keratoconus false positive topography in OS Figure 13 4 Maps Selectable showing a form fruste keratoconus false positive topography in OD 5 Differences between Placido and elev...

Page 22: ...degree of nuclear opacity PNS 6 1 Case 1 Unilateral high astigmatism with suspicion of bilateral keratoconus A male patient aged 45 years presented for the first time in 2010 to have his distance spe...

Page 23: ...wing abnormal pachymetry and elevation data with unambiguous signs of keratoconus in OD Figure 15 Fast Screening Report showing abnormal pachymetry and elevation data with unambiguous signs of keratoc...

Page 24: ...Figure 16 Belin Ambr sio Enhanced Ectasia Display version III showing keratokonus in OD Figure 17 Belin Ambr sio Enhanced Ectasia Display version III showing keratokonus in OS 6 The Fast Screening Rep...

Page 25: ...nd transplant deturgenscence was functionally assessed on the basis of the Compare 4 Exams display Figure 18 At one week postoperative central apical corneal thickness measured 670 m In the course of...

Page 26: ...24 Figure 19 Fast Screening Report showing the presurgical condition in a case of Fuchs dystrophy Figure 20 Fast Screening Report at one month after DMEK surgery 6 The Fast Screening Report...

Page 27: ...Figure 21 Corneal Optical Densitometry showing the presurgical condition in a case of Fuchs dystrophy Figure 22 Corneal Optical Densitometry at one month after DMEK surgery 6 The Fast Screening Repor...

Page 28: ...ainst his right eye Analysis based on the Pentacam Fast Screening Report revealed an abnormal value for K Max anterior surface as well as anterior and posterior elevation Figure 23 After calling up th...

Page 29: ...Maps Refractive with suspicious curvature and elevation maps of the anterior surface Figure 25 Compare 2 Exams showing changes in anterior surface elevation within a period of one week 6 The Fast Scr...

Page 30: ...r zone from 1 0 to 8 0 mm the Pentacam calculated right eye total cornea refractive power TCRP as having an almost constant astigmatism at around 1 00 1 10 D from the centre up to 5 0 mm peripherally...

Page 31: ...26 4 Maps Refractive showing with unremarkable elevation maps and curvature map in OD Figure 27 4 Maps Refractive showing unremarkable elevation maps and curvature map in OS 7 Corneal Power Distributi...

Page 32: ...re 28 Corneal Power Distribution showing normal power distribution in OD Figure 29 Corneal Power Distribution showing a markedly increased power from 2 0 to 3 0 mm in OS 7 Corneal Power Distribution d...

Page 33: ...g to patient information Uncorrected vision acuity was 20 30 in OD and 20 200 in OS Patient refers severe glare and starburst all day mainly at night OD sph 0 25 cyl 3 00 A 156 VA 20 20 OS sph 5 00 cy...

Page 34: ...progression in OS The pachymetric progression is abrupt in both eyes providing a significant indication of ectasia Figure 32 Figure 33 Probably mild ectasia could have been diagnosed prior to surgery...

Page 35: ...terested in further vision enhancement for her dominant right eye Her best spectacle corrected visual acuity BSCVA was 20 20 with sph 1 25 D The referring surgeon was concerned about post LASIK ectasi...

Page 36: ...This device routinely fails to correctly identify the posterior corneal surface in postoperative patients leading to underestimates of residual bed thickness and frequent incorrect diagnosis of post L...

Page 37: ...maps incorrectly suggesting ectasia in OD Figure 37 Pentacam 4 Maps Selectable revealing there to be no post LASIK ectasia In this example Orbscan measured the pachymetry 37 microns m thinner than Pen...

Page 38: ...Examination with the Pentacam 4 Maps Refractive display Figure 38 yielded a corneal thickness of 728 m resulting in a corrected IOP of 11 mmHg according to the Dresdner scale Further examination on t...

Page 39: ...o of 0 6 in both eyes The lens was clear and gonioscopy examination revealed a narrow angle in both eyes grade I II The anterior segment exam with the Pentacam Figure 41 documented an ACA of 22 5 degr...

Page 40: ...t in the differential display Figure 43 Figure 42 General Overview display 10 days after YAG laser iridectomy in OS showing improved ACA and ACD values Figure 43 Compare 2 Exams showing changes from b...

Page 41: ...ct of the treatment evident to her 9 3 Screening for narrow angles by Dilraj S Grewal MD 9 3 1 Case 1 A 64 year old Indian female patient presented for a routine eye exam Her vision was 20 20 in both...

Page 42: ...aphy OCT and retinal nerve fiber layer RNFL scans showed retinal thickness to be normal in both eyes Figure 49 Figure 45 General Overview display showing a low ACV shallow ACD and narrow angle in OD F...

Page 43: ...igure 47 24 2 Humphrey visual field full visual field in OD Figure 48 24 2 Humphrey visual field full visual field in OS Figure 49 Spectral domain OCT showingnormal RNFL thickness in both eyes 9 Glauc...

Page 44: ...year old Indian female patient presented for a routine eye exam Her vision was 20 20 in both eyes She was found to have a shallow anterior chamber on slitlamp biomicroscopy Gonioscopy showed Shaffer s...

Page 45: ...43 Figure 51 General Overview display showing a low ACV shallow ACD and narrow angle in OS 9 Glaucoma...

Page 46: ...fects in both eyes Figure 54 Figure 52 24 2 Humphrey visual field showing an early superior arcuate defect in OD Figure 53 24 2 Humphrey visual field showing an early inferior paracentral defect in OS...

Page 47: ...ng Figure 55 confirmed the diagnosis of phacomorphic glaucoma as evidenced by a shallow ACD of 1 75 mm an ACV of 65 mm3 and ACA of 17 5 degrees in the right eye An anterior vaulting of the lens was vi...

Page 48: ...46 Figure 56 Scheimpflug Image showing increased ACV deeper ACD and wider ACA following removal of the lens and posterior chamber IOL implantation 9 Glaucoma...

Page 49: ...6 Show Nasal Temp 7 Show Max Diameter 9mm 12 and Show Numeric Values 14 Anterior elevation posterior elevation Right click on the scale and set to Belin intuitive 75 m for refractive practice Belin in...

Page 50: ...are considered normal while differences between 12 m and 15 m are suspicious and differences 15 m are typically indicative of keratoconus Similar numbers about 5 m higher apply to posterior elevation...

Page 51: ...ation island patterns not astigmatism These numbers pertain to elevation in the central and paracentral region in an island pattern 10 2 Normal astigmatic cornea This 4 Maps Selectable display Figure...

Page 52: ...agittal curvature The curvature maps reveal a steep cornea K1 47 6 K2 50 2 but the elevation maps do not reveal any suspicious areas The pachymetry map is well centered with a thinnest reading of 546...

Page 53: ...e a similar pattern as does the anterior sagittal curvature The anterior elevation map is symmetric and the curvature shows a symmetric astigmatic pattern The pachymetry map is well centered with a th...

Page 54: ...re defined astigmatic pattern However because the posterior cornea contributes a much smaller amount to the overall refractive state of the eye the posterior astigmatism reads only 0 4 D in spite of a...

Page 55: ...astig 0 7 D The anterior elevation shows no defined pattern which is mirrored by the anterior sagittal curvature The corneal thickness is slightly high 583 m in the thinnest reading DIAGNOSIS normal...

Page 56: ...operties of the posterior cornea no cornea air interface differ from those of the anterior surface the refractive astigmatism of the posterior cornea is listed only as 0 3 D The pachymetry map shows a...

Page 57: ...on shows a normal astigmatic pattern as does the anterior elevation not shown The pachymetry maps show the thinnest regions OD at 492 m and OS at 483 m This is a normal eye topographically but one tha...

Page 58: ...or values are within the normal range while the posterior numbers are just outside the normal range The pachymetry map is normal revealing a thick cornea thinnest region 608 m with a normal pachymetry...

Page 59: ...show an asymmetric pattern Curvature is a reference based measure An asymmetric curvature pattern can occur with a completely normal astigmatic cornea when the apex line of sight and measurement axis...

Page 60: ...hrough a vertical cross section revealing severe flattening over most of the cornea an inferior band of thinning and a sharp change in corneal contour over the area of thinning PMD is one of the most...

Page 61: ...pachymetry distribution with a significant inferior temporal displacement of the thinnest zone At times the only indicator of potential pathology may be the magnitude and distribution of the corneal...

Page 62: ...somewhat irregular astigmatic pattern but without any obvious positive island The tangential curvature incorrectly locates the cone much more inferiorly than the cone location shown by both the poste...

Page 63: ...nd thinned to 499 m If the surgeon had only relied on anterior curvature and central corneal thickness readings this patient would have been classified as normal normal anterior curvature and central...

Page 64: ...f the thinnest area towards the area of the abnormal posterior elevation The left eye shows a relatively normal posterior astigmatic pattern but a distinctly abnormal pachymetry distribution with mark...

Page 65: ...tive deviation maximal at 33 m anterior and 89 m posterior with an accompanying displacement of the pachymetry map thinnest reading 485 m The tangential curvature map also shows inferior steepening bu...

Page 66: ...in over 10 of normal corneas Corneal tomography provides a three dimensional reconstruction of the cornea thus permitting evaluation of the anterior and posterior corneal surfaces and thereby the cre...

Page 67: ...in PIT between normal and keratoconic eyes over all locations considered was very high p 0 0001 Keratoconic corneas had a much higher thickness percentage increase than normal eyes on each of the 22...

Page 68: ...s of our studies served as a basis for engineering new summaries and graphs that would help clinicians explore CTSP and PIT so as to be able to objectively evaluate thickness profiles and detect ectas...

Page 69: ...corneal thickness for diagnosis and classification of corneal ectasia The CTSP and PIT graphs are furthermore relevant in evaluating abnormal thick corneas in endothelial disease They provide very re...

Page 70: ...68 Figure 78 Show 2 Exams Pachymetric showing a normal thin cornea Figure 79 Show 2 Exams Topometric showing an ectatic cornea 11 Corneal Thickness...

Page 71: ...and classification criteria for keratoconus are based on anterior corneal curvature data derived from corneal topography We wish to emphasize that the thickness profile described here should be used...

Page 72: ...SP and PIT increase sensitivity for the detection of very early forms of keratoconus we studied patients with keratoconus in one eye and in the other a cornea of normal surface curvature as evidenced...

Page 73: ...ymetric showing a normal cornea Compared with the specificity of artificial intelligence based indices for detecting ectasia topometric indices are fraught with high false positive rates especially in...

Page 74: ...periphery corneal swelling makes the cornea homogeneously thick decreasing the increase in thickness values towards the periphery We have found that the flattening of the CTSP and PIT curves occurs ev...

Page 75: ...73 Figure 86 Show 2 Exams Pachymetric showing a case of Fuchs dystrophy 11 Corneal Thickness...

Page 76: ...gure 88 Scheimpflug image showing clear cornea in OS with no peak in the densitogram for the endothelium 11 3 Case 2 Ocular hypertension by Prof Renato Ambr sio Jr Marcela Q Salom o MD The case below...

Page 77: ...respectively This is a case of normal thick corneas of correspondingly high stiffness leading to ocular hypertension There is no indication for topical medications to decrease the IOP Figure 90 HRT s...

Page 78: ...s membrane and the endothelium Camel s sign in both eyes Figure 91 Figure 92 This indicates a less transparent cornea Both lenses can be seen to lack clarity even with non dilated pupils In both eyes...

Page 79: ...th eyes HRT was not possible in OD due to impaired transparency of the ocular media early cataract and had a below average quality in OS Figure 95 Pascal Dynamic Contour Tonometer IOP measurements wer...

Page 80: ...guration is abnormal both in the image and according to Moorefield s classification This patient has glaucoma as well Figure 94 Specular microscopy in OD and OS Figure 95 HRT single initial report sho...

Page 81: ...ge pachymetry progression index 0 8 Fuchs dystrophy or oedema 0 8 average pachymetry progression index 1 2 normal or ocular hypertension average pachymetry progression index 1 2 ectasia The shapes of...

Page 82: ...troduced a measuring device that included both a magnification and a doubling mechanism enabling the examiner to match the corneal reflection to itself This technique was popularized by Helmholtz in 1...

Page 83: ...as able to provide a qualitative picture of approximately 50 of the cornea Antonio Placido however who is often credited with this technique was the first to photograph these corneal reflections Placi...

Page 84: ...t we understand how curvature and elevation measurement differ There is a common misunderstanding in the assumption that curvature maps reflect the shape of the cornea Curvature regardless of how it i...

Page 85: ...but these will not be discussed here Corneal thickness maps are easy to comprehend Corneal thickness is an absolute measurement representing the distance between the anterior and posterior surface Co...

Page 86: ...elevation qualitatively useful we need to display the data in a more clinically relevant manner To do this we typically display the elevation data against a non planar reference surface It needs to b...

Page 87: ...e reference surface to a fixed best fit sphere computed from the central 8 0 mm optical zone setting Manual 8 0 mm Fixing the area used to compute the reference surface is also necessary to allow comp...

Page 88: ...lly masking the cone A modification of the BFS called the enhanced reference surface utilizes the same 8 0 mm central optical zone but excludes a small portion of this data surrounding the TP on the c...

Page 89: ...lding an island of greater magnitude The enhanced reference surface is one component of the Belin Ambr sio Enhanced Ectasia Display a comprehensive tool for preoperative refractive surgery screening F...

Page 90: ...l portion of the cornea from the BFS computation the enhanced reference surface serves to further accentuate ectatic or conical protrusion while having little if any effect on normal corneas The Belin...

Page 91: ...ata base of normal and keratoconic corneas The major advance is that while an individual parameter s may fall outside the norm the final overall comprehensive reading may still be viewed as normal Fig...

Page 92: ...l astigmatic pattern The central cornea has a normal thickness at the apex of 532 m but shows little progression towards the periphery causing the PIT tracing to be relatively flat opposite of what yo...

Page 93: ...t value and TP displacement are all within normal limits The posterior elevation change is further heightened by the enhanced reference surface and the bottom display for the posterior elevation revea...

Page 94: ...e thinnest value at 568 m is normal The combination of a number of suspicious values however is enough to put the overall reading D well outside of the normal range at 3 23 SD from the norm and it is...

Page 95: ...phy There are also changes on the posterior surface both yellow more dramatic changes in the pachymetric progression Dp which is red at 3 70 SD from the mean and a mild displacement of the TP yellow T...

Page 96: ...nown as the enhanced BFS An exclusion map may be significantly different from its corresponding baseline elevation map or it may be very similar depending on the relative impact of the 4 mm exclusion...

Page 97: ...95 Figure 114 Belin Ambr sio Enhanced Ectasia Display version I showing elevation data on the left and pachymetry data on the right 12 Belin Ambr sio Enhanced Ectasia Display...

Page 98: ...ic eyes than it is in normals 0 9 0 23 mm p 0 05 Along with the TP the pachymetric display also evaluates the thickness profile of the cornea The basics and interpretation of the CTSP Corneal Thicknes...

Page 99: ...97 Figure 115 Placido topopraphy in OD showing no keratoconus Figure 116 Placido topography in OS showing no keratoconus 12 Belin Ambr sio Enhanced Ectasia Display...

Page 100: ...l thickness and anterior curvature The thinnest corneal reading in OS is below 500 m the pachymetric progression graphs are borderline in OD and abnormal in OS and the enhanced elevation maps show cha...

Page 101: ...99 Figure 118 Belin Ambr sio Enhanced Ectasia Display version I showing subclinical keratoconus in OD 12 Belin Ambr sio Enhanced Ectasia Display...

Page 102: ...mbr sio Enhanced Ectasia Display improves the ability to detect ectatic disease 7 8 The Ambr sio relational thickness maximum ARTmax 9 was 259 m in both eyes Figure 120 Figure 121 The final deviation...

Page 103: ...keratoconus in OD Figure 121 Belin Ambr sio Enhanced Ectasia Display version III showing forme fruste keratoconus in OS The Belin Ambr sio Enhanced Ectasia Display shows abnormal values for posterior...

Page 104: ...be an improvement of the refractive surgery screening process 17 18 However some studies have shown this scoring system to have drawbacks revealing high false positive as well as high false negative...

Page 105: ...d position of scattering phenomena that may occur within the cornea What is the clinical utility of corneal densitometry If performed in uniform conditions densitometry assessment can be used for maki...

Page 106: ...the precipitates due to the impossibility of targetingthe endothelial surface with retroillumination Figure 124 Once the patient had been started on a course of antibiotics and corticosteroids he sho...

Page 107: ...tical Densitometry display showing keratic precipitates after one week of therapy Figure 126 Corneal Optical Densitometry display showing keratic precipitates after two weeks of therapy 14 Corneal Opt...

Page 108: ...ear old patient with a history of stable keratoconus was treated by implantation of INTACS corneal ring segments The segments are readily visible in the densitometry screen Figure 127 The depth of the...

Page 109: ...ossible to examine the lamellar interface in greater detail When the visual outcome in the case of this 80 year old lady was slightly less than expected there were found to be specks or deposits of in...

Page 110: ...sualize the scar its depth in the cornea correlate it to corneal shape topography and its consequent impact on refraction In each and every patient with corneal scarring I begin my quest by using the...

Page 111: ...op slit lamp images of an on cornea scar Figure 131 General Overview showing findings on an in cornea scar in the Scheimpflug image 15 Using Pentacam technology to evaluate corneal scars planning and...

Page 112: ...niques but also as a means of educating my patients with a visual aid that they can understand In cases of moderate anatomical abnormality with structural instability i e keratoconus keratoglobus pell...

Page 113: ...lower 2 images show the impact after Laser PRK following previous INTACS to result in decrease in corneal astigmatism from 3 7 D to 0 3 D After corneal visual rehabilitation collagen cross linking can...

Page 114: ...measurable After IOL power calculation he then underwent cataract surgery with a precisely calculated lens implant and was brought to emmetropia and unaided 20 20 vision Figure 134 Corneal Optical De...

Page 115: ...owing a clear cornea following laser scar peel cataract present Figure 137 Slit lamp image showing a clear cornea following laser scar peel cataract present 15 Using Pentacam technology to evaluate co...

Page 116: ...st cataract surgery with toric lens implant giving 20 20 vision Figure 139 Slit lamp image showing status post cataract surgery with toric lens implant giving 20 20 vision 15 Using Pentacam technology...

Page 117: ...of lens exchange surgery using a toric lens implant in the second stage which eventually brought the patient to emmetropia and unaided 20 20 vision Figure 140 Corneal Optical Densitometry display afte...

Page 118: ...he emmetropic outcome after lens exchange surgery INTACS in place Figure 143 Slit lamp image after lens exchange surgery with an emmetropic outcome INTACS in place 15 Using Pentacam technology to eval...

Page 119: ...as INTACS in the US Anterior corneal curvature analysis showed significant inferior cone displacement and a maximum steepness of 50 D with the steepest part of the cone well below the pupillary margi...

Page 120: ...s classification based solely on anterior curvature Both the anterior and posterior elevation map as well as the pachymetry map locates the cone just at the inferior pupillary border giving a picture...

Page 121: ...and high order aberrations HOA Z 4 spherical Z 5 trefoil 5th order Z 6 astigmatism 6th order Figure 147 The keratoconus menu of the Pentacam identifies this cornea as an oblate postoperative cornea N...

Page 122: ...chymetric showing the pachymetry progression in an oblate postoperative cornea After the implantation of INTACS her visual acuity was OS sph 0 50 cyl 1 25 A 30 VA 20 20 The Scheimpflug image shows a s...

Page 123: ...thelial EpiON crosslinking using riboflavin 0 22 solution VibeX Xtra Avedro Inc Waltham MS USA The patient was subjected to 8 min of pulsed UV A light 1 sec on 1 sec off at 30 mW cm2 energy dose of 7...

Page 124: ...122 16 INTACS implantation Figure 151 Preoperative Scheimpflug image of the vertical section Figure 152 Postoperative Scheimpflug image of the vertical section...

Page 125: ...ious corneal surgery to design a display which contains all of the necessary information for screening treating patients The proper settings for the Holladay Report are automatically set correctly by...

Page 126: ...tting pull down menu then click Save and check the Lock Settings box Figure 155 shows the map overlay for the corneal thickness map and Figure 156 the overlay for the other 5 maps Figure 154 Miscellan...

Page 127: ...Medical Optics Santa Ana Calif with a total SA of 0 27 m the Acrysof SN60WF Alcon Inc Fort Worth Texas which is nominally 0 18 m and varies with IOL power and the SofPort AO Bausch Lomb Rochester New...

Page 128: ...s In general values beyond 2 SD are suspicious of pathology and those beyond 3 SD are considered abnormal statistically The steep red and flat blue semi meridians principal are shown in the 3 mm the 3...

Page 129: ...nnest pach m m m mean 543 SD 33 509 576 2 SD 67 476 609 3 SD 100 442 643 The central lower map relative pachymetry RP Figure 157 shows why a negative meniscus lens has a predictable thickness from its...

Page 130: ...Variables indicating shape and SA of cornea front surface Q value Eccentricity Zernike 4 0 SA Seidel Longitudinal SA D 0 54 0 73 Q 2 0 00 0 00 0 26 0 51 Q 2 0 19 1 03 0 00 0 00 0 38 2 10 0 26 0 51 Q 2...

Page 131: ...l axial radius of curvature mm versus zone diameter red and the mean ring axial radius of curvature mm versus zone diameter green The blue values represent refractive power D of a zone as one moves fr...

Page 132: ...ues are calculated instantaneously The lower right map Figure 158 shows the EKR power map uses both front and back power Snell s law and represents the values that are appropriate for IOL power calcul...

Page 133: ...pupil diameter is 5 48 mm and taken with low light levels but depending on the location of the device illuminated room the value is usually smaller than the scotopic pupil size one obtains with infrar...

Page 134: ...e axial power lines green and red are not and therefore do not reflect actual refractive power changes due to the cornea The distribution of EKR in the 4 5 mm zone shows that the EKR65 mean 40 76 glob...

Page 135: ...nting in the direction of the hot spot on the curvature maps On the RP map the minimum 4 6 is at the limit of suspicious and is also located at the point of peak power on the tangential curvature map...

Page 136: ...ry little from 43 02 to 42 63 0 39 D from the 3 to 4 5 mm zone The EKR65 power increases SA as the pupillary diameter increases This visual performance is also affected by KC and is limited by the irr...

Page 137: ...normal green at the 6 mm diameter The center has a front elevation front is 8 m at the center and on the elevation back is 14 m This elevation on the back is suggestive of ectasia The steepened radiu...

Page 138: ...priate Ks for IOL calculation would be at the 3 0 mm zone and are EKR65 flat K1 35 23 A 146 and EKR65 steep K2 35 30 A 56 The axes are quite different from the 4 5 mm zone but this is due to the small...

Page 139: ...taract surgeons to understand the lifestyle of each patient the ocular pathology and the optical quality of the eye before surgery This article explains on the basis of case examples how the Pentacam...

Page 140: ...ap is used to determine any abnormality in corneal shape In the upper center is the map of Total Corneal Refractive Power TCRP TCRP n 1 376 for cornea n 1 336 for aqueous is calculated from the anteri...

Page 141: ...nformed consent regarding the effects of corneal irregular astigmatism on quality of vision Total HOA 0 360 m shows mild irregular astigmatism and SA 0 403 m is relatively high but within the normal r...

Page 142: ...how postoperative refractive errors can be avoided following cataract surgery in post LASIK patients As is well known patients for whom IOL power was calculated by conventional methods often experienc...

Page 143: ...he software automatically calculates the density of a central 3 dimensional reference block grading it from 0 to 5 During conventional cataract surgery phacoemulsification has to be performed The effe...

Page 144: ...of 2 99 seconds was calculated 19 3 Case 2 High PNS and high EPT In OD of this caucasian male patient one sees immediately that lens clarity is considerably reduced compared to the first patient This...

Page 145: ...stigmatism is based on the 1 376 refractive index of cornea whereas the KA is based on the 1 3375 keratometric index which was developed to take into account the influence of the posterior corneal sur...

Page 146: ...was 20 03 mm and a 33 00 D toric Acrysof Alcon Fort Worth TX was calculated for emmetropia The Pentacam detected a WTRA whose measurements at 3 mm Figure 170 Figure 171 yielded a 0 8 D difference bet...

Page 147: ...of axial length and corneal power 50 suggested a T4 IOL to correct the KA residual predicted astigmatism 0 23 D 39 and a T3 IOL to correct the TCRP astigmatism residual predicted astigmatism 0 20 D 36...

Page 148: ...was calculated for emmetropia Traditional KA measurement Figure 172 showed a value of 1 9 161 which was significantly lower than the Pentacam TCRP at 3 mm Figure 173 measuring 2 8 D 160 3 Figure 172...

Page 149: ...riented at 160 One month after surgery the patient had no residual refractive astigmatism 20 3 Case 3 Cylinder overcorrection from measurement of keratometric astigmatism A 71 year old man underwent c...

Page 150: ...of 0 2 D 90 we targeted a correction of 1 37 D 76 A SN6AT4 IOL was implanted at 75 One month after surgery the refraction was sph 0 25 cyl 0 25 A 120 Using the KA data would have led to cylinder overc...

Page 151: ...as Phaco Optics Okulix are linked via interface New algorithm for intraocular lens power calculations after myopic laser in situ keratomileusis based on rotating Scheimpflug camera data Richard Potvin...

Page 152: ...L The Pentacam allows us to measure very easily and accurately the anterior chamber and so determine if there is enough space to implant an iris fixated Artisan phakic IOL One can measure not only the...

Page 153: ...A 180 OS sph 0 50 cyl 1 00 A 180 We had a good pre op planning process and a happy post op patient 22 2 3D pIOL Simulation and Aging Prediction by Prof Burkhard Dick Sabine Buchner Optometrist 22 2 1...

Page 154: ...efore we checked the possibility of a pIOL implantation A 3D simulation of the fit of a pIOL gave a swift answer to this Because of her big pupil size it was clear that only the Artisan Verisyse with...

Page 155: ...cing the distance between them A possible consequence would be endothelial cell loss a risk that must be taken into account and avoided For this purpose the Pentacam offers unique aging prediction sof...

Page 156: ...ging by the first impression of her anterior chamber conditions this patient appears suitable for pIOL implantation Without the Pentacam we would have done the implantation However because of the pred...

Page 157: ...used the Pentacam 3D pIOL Simulation and Aging Prediction to simulate the fit of the pIOL and to check its position over the course of years following surgery using the aging prediction module pIOL l...

Page 158: ...inimum clearance is 1 mm Conclusion The amount of endothelium cells was in the normal range The patient was young and her refraction could be expected to remain stable over the next year The minimum c...

Page 159: ...OL and endothelium should be greater than 1 mm Endothelial cell density should be at least 2000 per mm Dislocation of the pupil should be no greater than 1 mm The Scheimpflug image in Figure 183 shows...

Page 160: ...kic IOL implantation Figure 184 3D pIOL Simulation and Aging Prediction showing a large iris convexity The following warning appears Automatic pIOL alignment may be negatively influenced by large iris...

Page 161: ...80 sph 14 25 cyl 6 0 A 0 in OS The thinnest pachymetry value was 408 m in OD and 395 m in OS Given the severity of the clinical picture the moderately thin cornea and the presence of contact lens into...

Page 162: ...ASIK ectasia treated by transepithelial crosslinking followed by phakic intraocular lens implantation in both eyes Figure 186 Scheimpflug Image after transepithelial crosslinking in OD A and OS B slit...

Page 163: ...act surgery would be the only option to improve her visual acuity She was now presenting at our clinic for a second opinion Scheimpflug imaging was successful Figure 187 in perfectly documenting the p...

Page 164: ...Pentacam revealed only a small degree of corneal astigmatism Figure 189 but also a peripheral hot spot black circle BSCVA was 20 25 after removing the first sutures The question now was whether also...

Page 165: ...20 80 in both eyes The Pentacam delivered the solution in two seconds The right eye had a cataract and undetected keratoconus Figure 190 Figure 192 The left eye had no cataract but undetected keratoco...

Page 166: ...164 23 Case reports from daily practice Figure 193 4 Maps Refractive of OS Figure 194 Pachymetry progression in OS Figure 195 Scheimpflug image of OS...

Page 167: ...stion open regarding the right eye Which K reading should we use for the IOL calculation The Pentacam gives us an actually measurement ot the central power of the cornea We used 42 9 for both K1 and K...

Page 168: ...ms had started after wearing her contact lens 6 hours in OS She woke up in the next night with moderate secretion She complained of photophobia and blurred vision in OS when wearing glasses A Pentacam...

Page 169: ...inolones initiating treatment with an attack dose of one drop every ten minutes during the first hour followed by hourly doses around the clock One day later she reported improvement in her vision as...

Page 170: ...d female patient presented with incisional edema 12 months after phacoemulsification Endothelial morphology revealed large cells with pleomorphism and polymegathism Central cell count was 1 079 cells...

Page 171: ...or camel sign over the edematous area on the densitometry This is caused by the high reflectivity of the posterior layer of the cornea at the incision level 23 6 Case 6 Corneal thinning after herpeti...

Page 172: ...umenting corneal thickness The thinnest spot is displayed in the pachymetry map and can also be seen in the Scheimpflug images facilitating follow up examination Figure 204 The patient was kept on pro...

Page 173: ...d one re treatment for removal of epithelial ingrowth asked for a second opinion The slit lamp examination Figure 205 revealed epithelial ingrowth under a moderately deep cap reaching the center of th...

Page 174: ...Maps Refractive confirming epithelial ingrowth The pachymetry map in the 4 Maps Refractive Figure 207 showed this effect as well even in the presence of an opaque cornea The Pentacam was useful for e...

Page 175: ...p images 24 Scheimpflug and slit lamp images 24 1 Corneal dystrophy Figure 209 Slit lamp photo documenting corneal dystrophy on the posterior surface Figure 208 Scheimpflug image revealing corneal dys...

Page 176: ...Scheimpflug and slit lamp images 24 2 Congenital anterior pyramid cataract Figure 211 Slit lamp photo showing an anterior pyramid cataract Figure 210 Scheimpflug image showing an anterior pyramid cat...

Page 177: ...5 24 Scheimpflug and slit lamp images 24 3 Posterior capsular cataract Figure 213 Slit lamp photo showing a posterior capsular cataract Figure 212 Scheimpflug image showing a posterior capsular catara...

Page 178: ...176 24 Scheimpflug and slit lamp images 24 4 Nuclear cataract Figure 215 Slit lamp photo showing a nuclear cataract Figure 214 Scheimpflug image showing a nuclear cataract...

Page 179: ...177 24 Scheimpflug and slit lamp images 24 5 Posterior synechia Figure 217 Slit lamp photo showing posterior synechia Figure 216 Scheimpflug image showing posterior synechia...

Page 180: ...6 Pterygium Figure 219 Topography revealing pterygium Figure 220 Slit lamp photo of an eye with pterygium Figure 218 Scheimpflug image in 190 showing a case of pterygium 24 Scheimpflug and slit lamp...

Page 181: ...D sph 2 50 OS sph 1 00 The Pentacam Show 2 Exams display showed an optimal eccentricity on the 30 meridian of both eyes namely 0 50 in OD and 0 49 in OS permitting us to propose an orthokeratology tre...

Page 182: ...atient was examined 4 times within 2 months to follow up the condition of the cornea and the efficacy of the treatment was confirmed by a comparison of all four exams Figure 222 Figure 222 Compare 4 E...

Page 183: ...rning after wearing the lens over night and in the late afternoon Examination with the Pentacam using the Compare 2 Exams display confirmed that the effect of the ortho K lens was reversed during the...

Page 184: ...astasios John Kanellopoulos MD George Asimellis PhD J Refract Surg 2014 30 2 88 92 Curvature Analyses of the Corneal Front and Back Surface Bo o Vojnikovi Nikica Gabri Iva Dekaris and Branka Juri Coll...

Page 185: ...tcome in superficial corneal opacities Mohammad A Rashad Clinical Ophthalmology 2012 6 885 894 2012 Rashad publisher and licensee Dove Medical Press Ltd Corneal Densitometry as an Indicator of Corneal...

Page 186: ...o P Guerra MD Ricardo Louzada MD Abhijit Sinha Roy PhD Allan Luz MD William J Dupps MD PhD Michael W Belin MD FACS J Refract Surg Posted online July 29 2011 2011 Tomographic Normal Values for Corneal...

Page 187: ...stics of keratoconus assessed by rotating Scheimpflug imaging Illes Kovacs MD PhD Kata Mihaltz MD Janos Nemeth MD DSc Zoltan Z Nagy MD DSc J Cata ract Refract Surg 2010 36 1101 1106 Q 2010 ASCRS and E...

Page 188: ...ue Makoto Saika Toshifumi Mihashi Takashi Fujikado Yasuo Tano Investigative Ophthalmology Visual Science June 2009 Vol 50 No 6 Effect of bottle height on the corneal endothelium during phacoemulsifica...

Page 189: ...onus Eyes Using Scheimpflug Photography Charles R Edmonds O D F A A O Shu Fen Wung Ph D A C N P F A A N Bart Pemberton O D F A A O and Steven Surrett B S Eye Contact Lens 2009 3 120 122 Comparison of...

Page 190: ...12 040 Comparison between central corneal thickness measurements by Oculus Pentacam and ultrasonic pachymetry Hani S Al Mezaine Saleh A Al Amro Dustan Kangave Abdulkareem Sadaawy Taher A Wehaib Saleh...

Page 191: ...L Simulation for High Res Imaging This software provides preoperative detection of post operative phakic IOL positioning H BURKHARD DICK MD MANA TEHRANI MD H Burkhard Dick MD J Cataract Refract Surg T...

Page 192: ...almology 2006 doi 10 1016 j ophtha 2006 01 063 Progress o da espessura corneana do ponto mais fino em dire o ao limbo estudo de uma popula o normal e de portadores de ceratocone para cria o de valores...

Page 193: ...s Giacomo Savini and Kristian N ser Investigative Ophthalmology Visual Science February 2015 Vol 56 No 2 829 Precision of 5 different keratometry devices Jonas Vejvad N rskov Laursen Peter Jeppesen Th...

Page 194: ...different measurement technologies Nienke Visser MD Tos T J M Berendschot PhD Frenne Verbakel BSc John de Brabander PhD Rudy M M A Nuijts MD PhD J Cataract Refract Surg 2012 38 1764 1770 Q 2012 ASCRS...

Page 195: ...e cataract grading by Scheimpflug imaging and effect on operative fluidics and phacoemulsification energy Donald R Nixon MD J Cataract Refract Surg February 2010 Intraocular lens power calculation aft...

Page 196: ...and Atlas B Dom nech D Mas E Ronda J P rez J Espinosa C Optica Pura Y Aplicada 2009 42 1 51 60 The Comparison of Central and Mean True Net Power Pentacam in Calculating IOL Power After Refractive Surg...

Page 197: ...ract Refract Surg 2007 33 1041 1044 PIOL Simulation for High Res Imaging This software provides preoperative detection of postope rative phakic IOL positioning H Burghard Dick MD Mana Tehrani MD H Bur...

Page 198: ...Singh Grewal MD J Cataract Refract Surg 2007 33 116 119 Scheimpflug Imaging in Late Capsular Bag Distention Syndrome After Phacoemulsification Rajeev Jain MS Dilraj Grewal MBBS Rajeev Gupta MS Satinde...

Page 199: ...heimpflug camera imaging Shuning Li MD PhD Hongtao Wang MD Dapeng Mu MD PhD Jing Fu MD Xiaozhen Wang MD PhD Jian Wang MD PhD and Ningli Wang MD Clinical and Experimental Ophthalmology 2010 38 10 Measu...

Page 200: ...capsule rupture following closed globe injury Scheimpflug imaging pathogenesis and management D S Grewal R Jain G S Brar S P S Grewal European Journal of Ophthalmology Vol 18 no 2008 Nanophthalmos Ul...

Page 201: ...ractive surgery Curr Opin Ophthalmol 2013 24 4 310 20 9 Ambrosio R Jr Caiado AL Guerra FP et al Novel pachymetric parameters based on corneal tomography for diagnosing keratoconus J Refract Surg 2011...

Page 202: ...ation of corneal shape and biomechanics before LASIK Int Ophthalmol Clin 2011 51 2 11 38 28 Ambrosio R Jr Ramos I Faria Correia F Belin MW Tomographic Screening for Ectasia Susceptibility Analysis mus...

Page 203: ...i G Versaci F Vestri G et al The influence of posterior corneal astigmatism on total corneal astigmatism in eyes with high moderate to high astigmatism J Cataract Refract Surg 2014 40 1645 1653 48 Sav...

Page 204: ...reening Report showing suspicious values of K Max anterior surface and anterior and posterior elevation 26 Figure 24 4 Maps Refractive with suspicious curvature and elevation maps of the anterior surf...

Page 205: ...ofile CTSP 64 Figure 76 Thickness profile in an ectatic and a normal eye 66 Figure 77 Show 2 Exams Topometric showing a normal thin cornea 67 Figure 78 Show 2 Exams Pachymetric showing a normal thin c...

Page 206: ...of the same eye at the patient s initial presentation 104 Figure 125 Corneal Optical Densitometry showing keratic precipitates after one week of therapy 105 Figure 126 Corneal Optical Densitometry sh...

Page 207: ...f 1 4 D 110 8 144 Figure 171 Corneal Power Distribution display showing a lower amount of astigmatism at 0 6 D 114 9 145 Figure 172 Topometric showing a keratometric astigmatism of 1 9 D 161 146 Figur...

Page 208: ...o documenting corneal dystrophy on the posterior surface 173 Figure 210 Scheimpflug image showing an anterior pyramid cataract 174 Figure 211 Slit lamp photo showing an anterior pyramid cataract 174 F...

Page 209: ...N 1243 normal eyes internal unpublished data by J T Holladay 128 Table 7 Back elevation near min RP N 1243 normal eyes internal unpublished data by J T Holladay 128 Table 8 Maximum back elevation N 12...

Page 210: ...rneal thickness spatial profile cyl cylinder D diopter s EKR EKR65 equivalent keratometer readings equivalent keratometer readings 65 EPT effective phacoemulsification time HRT Heidelberg Retina Tomog...

Page 211: ...Specification R radius RGPCL rigid gas permeable contact lens RK radial keratotomy RNFL retinal nerve fiber layer RP relative pachymetry SA spherical aberration SD standard deviation sph sphere TCA to...

Page 212: ...ke University 2351 Erwin Road Durham North Carolina 27705 USA Phone 1 617 584 2334 Fax 1 919 681 6474 Email dilraj gmail com Arun C Gulani MD GULANI VISION INSTITUTE 8075 Gate Parkway W Suite 102 103...

Page 213: ...de Jos J Rozema MSc PhD Department of Ophthalmology Antwerp University Hospital Wilrijkstraat 10 2650 Edegem Belgium Email Jos Rozema uza be Giacomo Savini MD Studio Oculistico d Azeglio Via d Azegli...

Page 214: ...212 The following pages remain free and offer space for personal notes...

Page 215: ...LUS Optikger te GmbH OCULUS has been certified according to DIN EN ISO 13485 and therefore sets high quality standards in the development production quality assurance and servicing of its entire produ...

Page 216: ...US Optikger te GmbH Postfach 35549 Wetzlar GERMANY Tel 49 641 2005 0 Fax 49 641 2005 295 E Mail export oculus de www oculus de OCULUS USA info oculususa com OCULUS Asia info oculus hk OCULUS Czechia o...

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