Diabetes is well known and you can hear it everywhere. Still, diabetes is an insidious disease, especially on the eye. The affected patient often feels very healthy and he is supposedly doing well. If restrictions occur diabetes shows its evil side. Diabetes is like a ball, which was triggered and the direction and speed, one can only guess. Life will never be the way it once was. Therefore it is best to give diabetes not a chance. Eye doctors in collaboration with other physicians and the diabetes specialists are very important partners of the patient. The main goal is an indepedent living and to enable a high quality of life.
Our esteemed colleague, Dr. Martin K. Schmid, Co-Medical Chief at Eye Clinic Lucerne, Switzerland, proved to us the honor on 7th GETOCT meeting in Lucerne. He lectured in close collaboration with the public on diabetes and OCT.
Optical Coherence Tomography (Optische Kohärenztomographie, OCT): Time ist so short to do only routine work, you can be sure that there must be something more to be discovered. What should you say? There are sufficiently OCT scanner and the market is saturated. The poor ophthalmologists should not be plagued with all with the machines. Are you still waiting for the right OCT scanner to buy or to work with? Are you waiting for the 100 procent machine? This device doesn’t exist!
View user video about OptosOCT SLO:
Yet! Optos has dared, and it is amazing what their brand new OCT scanner is capable. As a world first blog we are reporting about a new all-in-one device suitable for nearly every purpose: OptosOCT SLO.
Components of the System
The device is comparable to the other OCT scanner with a dual setup: a scanner unit and a separate aquisition/analysis standard PC system (a screen and keyboard with mouse).
As a separate part a frontlens is included for anterior segment imaging which must be screwed to the anterior part of the optical head.
Start the OCT Engines
Compared with other OCT’s the launch of the system is very simple, very smooth and user friendly. One must press only two buttons on the main power switch/PC, the system starts by itself and is ready, no separate configuration is needed.
Patient Screen
The input of patient data is a bit a cumbersome solution. In particular, the birth date is inconvenient to enter. The patient screen has a bit a confusing design, because it is mixed up with different tabs of patient data, acquisition protocols and analysis.
A standard manually adjustable head rest is offered to ensure a good positioning of the patient. Once the alignment is carried out correctly the OCT scanner is guided by using the operator’s controls.
A special feature is that the live image of the CCD camera on the screen is to be find unobtrusively at the right bottom corner. For beginners, this may be somewhat confusing, because the fast exact focusing is regarded as the primary key setting. The workflow would be more intuitive if the eye of the examiner is guided in a serial way on the screen.
Once the three presented white dots are displayed sharp, clear and at a minimum size the measurement can begin. On the screen a relative nice infrared image of the fundus is projected. Fine adjustment of lateral and axial movements are corrected using the joystick.
For larger corrections the chinrest is moved by using the up / down buttons. A little disadvantage is that the patient’s head behind the scanning unit virtually disappears so that one has not always a direct visual control on the positioning and the patient’s condition.
Potpurry of Scan Protocols
The OptosOCT SLO system shows its strengths: a whole potpurry of acquisitions protocols is disclosed. The tomographic imaging contains all standard protocols by means of Line Scanning, Raster Scanning, Radial Scanning, 3D Retinal Topography, RNFL Scannning, Optic nerve Topography.
Those who still want more can use the Cornea-Lens-Module: a separate lens has to be screwed on the optical head of the scanner. It takes a little finesse, because the grooves of the anterior chamber lens are a little too fine shot, but it goes pretty fast.
This extension includes a relative detailed imaging of the cornea, the anterior chamber and even the angle. The quality of no current OCT system at 800nm is outstanding in relation to the cross sectional imaging. But the OptosOCT SLO is moving in the medium quality range. Therefore, it is still a gift without being asked for: corneal pachymetry may be performed as well. That might be a very nice additional bonus in patients with corneal pathologies or glaucoma.
Fast and easy Signal Centration
An ideal solution is to center the OCT signal. In other OCT devices with buttons, the signal must be moved gradually into the lower third of the scanning window. Some OCT machines have an auto adjust button which sometimes fires beyond the objective. With OptosOCT SLO a cross-sectional image on the screen is simply packed with the mouse and brought out where you want it. Very comfortable. Then comes the ready for take off: aquistion of the OCT signal! For this you press the button “AUTO” next to the joystick or on the screen.
Then something strange happenes. Nothing happens! Because the OptosOCT SLO , uses only one light source it has a “break”, which is uncommon when compared with other devices that have a permanent live SLO scan. On the screen it is shown that the system has to run a “warm-up”.
This auto reference is found in other scanners, too, and is called calibration for example, but it interferes less, because the live-SLO image always allowes to control the patient’s eye. This is a pure matter of habit and of no further importance.
Additional capabilities: OCT viewer
There is a primarily viewer software on the PCand it is easy to use. But there is a very comfortable, additional support from Optos: an external OCT data viewer software is available, you just have to unzip it , double click only, and voilà, all your recorded OCT data can be imported to any PC and be considered whenever you have time and desire.
In comparison with other OCT viewer installations, it is solved in an very elegant way and even inexperienced PC user will enjoy it. It just works!
Summary
The OptosOCT SLO is an eye catcher, is beautifully designed and very well made. It leaves a good impression, is relatively easy to use and to delegate. The presentation of the OCT scans is good compared to other standard OCT systems and is certainly sufficient for everyday clinical practice, but it is not enough to the absolute top of OCT quality. On the technical side the user interface may be simplificated to improve the workflow, but one gets along well. Very surprising are the many possibilities: cornea, anterior chamber, retina, glaucoma. As only OCT device, it provides a built-in micro-perimeter with many simulations. This can be helpful in the combined analysis of morphology and function in case of glaucoma, macular degeneration or in central serous retinopathy (CSR).
What is extremely encouraging is the price! For about 62 000 Swiss Francs as an introduction package in Switzerland one can get an exceptionally good equipped OCT system, even including the cornea module and micro-perimetry and possibly even the external viewer software and one-year-full range service.
Of course that’s a lot of money. But for this you nearly get a “Swiss Army Knife OCT” with lots of possibilities and one may ask: healthy vision, what is it really worth?
Eye doctors are experts at recognizing patterns. Every day, they compare the eyes of their patients with pictures from their clinical experience. Still, often we are blind to perceive a change. GETOCT begins here a simple, fun workout called Eye Acrobatics.
You must consciously direct your attention to individual details to find differences in virtually identical images. Find in this proliferative diabetic retinopathy (PDRP) six subtle differences.
Find the best apple performing the GETOCT Apple Test! Apples look good, taste, and contain many healthy vitamins for healthy eyes! How can you find the most delicious apple? Just make the GETOCT Apple Test. Download: Big Apple Test GETOCT
Changing life! In his third part of pitfalls with OCT, it is shown how careful one must be with the interpretation of OCT images.
We must not be satisfied only with beautiful pictures. You have to go into details and see and read the pictures like a book to get the correct diagnosis. Then, OCT will be an exciting experience that can change lifes.
Interpretation of OCT is awareness!
Interpretation of an OCT image means brightening of something, explaining and laying out the findings. OCT images are some kind of a transmitter, the interpreter is the receiver of an hidden information. Your answers to an OCT image are linked to your experiences, your interest and willingness to lay down the blinders and your prejudices. The answer to a question also affects the other answers. Put nothing into the image what is not there!
It’s a challenge to record a good OCT image. The even greater challenge is the correct interpretation! A major risk ist the danger of subjectivity and a rapid satisfaction. Search the challenge of OCT images! Nothing is more boring in your career as an eye doctor when you do the same every day.
As a source of enlightenment: getoct.com database
A big help is to consider as many OCT images as possible to achieve a “cerebral calibration “. Hundreds of annotated OCT images and videos are waiting to be discovered, through you.
Don’t miss anything really occurring
Dr. Hasler says at the getoct academy 2011, that a perfect instruction of the patient leads to good OCT images. You have first to prepare a good timing to start the recording at the right moment. It is of advantage to get both: OCT scan and corresponding infrared image of the fundus. These images are linked to each other and improve the orientation. If the scans are not perfect, it is worthwhile to start again. Immediately delete useless images to keep your computer clean.
Dr. Hasler: the algorithme (red line) follows the wrong way and leads to an erroneous measurement.
Algorithme makes mistakes (red/white line): OCT mapping and thickness imaging is nonsense (X) by Dr. Hasler.
Highly myopic eyes are difficult
OCT scanners are designed for normal-sighted eyes and sometimes have a button for highly myopic eyes. An oblique cut makes the algorithm work hard and leads more frequently to errors. Thus one has to check only the individual cross-sections of whether the algorithm has done his work satisfactorily.
The quality of an individual OCT cut influences the construction and the representation of the three-dimensional volume. If the cross section is poor in quality, the 3D representation is useless.
3D images are a summary of cross-sections and if they look strange you have to switch back and look at the cross section level. The OCT scanner analyzes the samples using an algorithm, so a „ simple calculation method“. The 3D OCT has the advantage that you can quickly scroll through a lesion, to detect and to estimate the dimensions and to identify mistakes easier.
In addition, 3D OCT is a good training to discover the anatomy of the eye and the problem is explained in an impressive way to the patient. Interpretation of OCT
The most difficult task is the correct interpretation of the OCT images. There is an enormous achievement to get a good OCT image. Good interpretation is a real challenge.
Dr.med.PeterMaloca recommends a multi-stage procedure for an accurate diagnosis: Checklist OCT pre-interpretation:
1. OCT practice:
Only practice makes perfect! Who does not look exactly on OCT images, will never learn it. 2. OCT network – calibration
Get in touch with experienced OCT users. Visit an OCT congress, for example the annual getoct academy in Lucerne (in German) and join the community at getoct.com. Upload your pictures to getoct.com, ask the community.
OCT interpretation in 5 getoct steps by Dr. med. Peter Maloca: 1. Orientation: where are you? For a proper assessment of OCT images you have to orient yourself first. Say nothing of what you can not prove or show on the OCT images! 2. Findings: describe only what you really see in simple words. 3. Summarize the findings 4. Link the findings to a diagnosis (interpretation) 5. Be honest: self-criticism/what else? Be honest! Say nothing what you have not checked for alternatives! Don’t skip lesions! Twist nothing! There are no stupid questions. Only someone who has no questions is stupid. Serve the OCT scans and do not abuse it for your self-expression! 6. Explain: explain to the patient the diagnostic findings. If he understood it, you have understood it.
Steps of interpretation OCT by Dr Maloca
***
OCT-Interpretation von Dr. med. Peter Maloca:
1. Orientierung auf dem OCT- Bild: wo bist Du? Für eine angemessene Bewertung der OCT-Bilder müssen Sie sich zuerst orientieren. Sagen Sie nichts, was Sie nicht beweisen können, zeigen Sie es auf den OCT-Bildern! 2. Befunde: beschreiben Sie in einfachen Worten nur, was Sie wirklich sehen. 3. Zusammenfassung der Befunde 4. Verknüpfen Sie die Befunde zu einer Diagnose (Interpretation) 5. Seien Sie ehrlich, Selbstkritik, was könnte es sonst noch sein?
Seien Sie ehrlich! Sagen Sie nichts, was sie nicht nach Alternativen geprüft haben! Lassen Sie keine Läsionen aus! Verdrehen Sie nichts! Es gibt keine dummen Fragen. Nur jemand, der keine Fragen hat, ist dumm. Missbrauchen Sie die OCT scans nicht zu Ihrer Selbstdarstellung!
6. Erkläre! Erklären Sie dem Patienten die Befunde. Wenn er es verstanden hat, haben Sie es auch verstanden.
Main problem in OCT (optical coherence tomography) is that things are interpreted in the pictures, they really do not exist. Pitfalls with OCT, technical aspect, case presentation, view video from getoct academy 2011.
It’s a great honor to welcome Dr. med. Pascal Hasler, Basel, at the 6th getoct academy in Lucerne/Switzerland. The problem with OCT congresses is, that everything looks wonderful. Everyone seems to know everything and no one dares to admit mistakes. Therefore, Dr. Pascal Hasler will show you in this video pitfalls using OCT. In the first part technical aspects are discussed. In the second part pitfalls of interpretation are shown. Therefore it is important that there are such courses as the practice-oriented getoct academy in Lucerne!
getoct academy 2011 Dr. Maloca and Dr. Hasler
Dr Hasler says that there are four main sources of error using OCT: patient dependent, cooperation between patient and examiner, wrong scanner settings and above all interpretation of OCT images, which is an extraordinary challenge.
Here is a summary of Dr. Hasler speech, held at the 6. getoct academy 3 December 2011:
Pitfalls with OCT, technical aspect, case presentation
1. Sources of error in patient
miosis: OCT in miosis is possible, but difficult due to lower signal strength, no accurate centering of laser beam
small interpalpebral space/ptosis
in dry eye use of moisturizing eyedrops before scanning
wrong indications for OCT: with vitreous hemorrhage OCT is practically impossible 2. Cooperation between patient and examiner:
poor visual acuity is equally to poor fixation: expand inner fixation target, use external fixation light
restless patients: shorten scanning, ask for assistance to fix the head
alternatively use the quick scan mode even when you loose image quality
scan rather an individual, low qualitiy cross scan than a fullrange measurement 3. Wrong settings on OCT scanner:
choose corresponding diopters, may be set automatically
the centering should be focused on the hot spot orthogonally if possible
measurement on correct eye and correctly stored
choose the right scan protocol: in children, one must often use protocols others than in adults
observe the quality of the scan signal observing the intensity chart
OCT is also useful for advanced cataract to evaluate the retina because the wavelength of the laser light is not so impeded by the cloudiness oft he cataract.
4. Interpretation of OCT
The most difficult task is the correct interpretation of the OCT images. There is an enormous challenge to get a good OCT image. Still, good interpretation of OCT iamges is an extraordinary challenge!
New video:
Dr. med. Peter Maloca recommends a multi-stage procedure for an accurate diagnosis: 1. First patient data
Is it the right patient (name, age)? Is it the right eye? 2. Anatomy
Where are normal, healthy structures?
Where are different structures?
Signs of activity (thickening, accumulation)?
3. Descriptive diagnosis
Try to describe the nature of the different structures first without trying to make a diagnosis: “I see a fine line that runs to the center of the retina, where spaces are present and there is a gap in the center of the retina” 4. Working diagnosis – differential diagnosis
Count for possible diagnoses. Which is less? What is rare is rare. Ask your colleagues. Upload some images to getoct.com and ask your getoct friends. 5. Diagnosis, synopsis
Which diagnosis is best suited to clinical picture and the other results? 6. Follow-up
What happens during the next time?
The biggest mistake in OCT is to ask: does the OCT suits my diagnosis instead of matches my diagnosis to the OCT?
***
Dr. med. Peter Maloca empfiehlt ein mehrstufiges Verfahren zur korrekten OCT-Diagnose:
OCT-Checkliste von Dr. med. Peter Maloca:
1. Patientendaten
Ist es der richtige Patient (Name, Alter)? Ist es das richtige Auge? 2. Anatomie
Wo sind normale, gesunde Strukturen?
Wo sind abweichende Strukturen?
Aktivitätszeichen (Verdickungen, Einlagerungen)? 3. Deskriptive Diagnose
Beschreibe die Art der abweichenden Strukturen zuerst ohne eine Diagnose erzielen zu wollen: “Ich sehe eine feine Linie, die zur Netzhautmitte zieht, wo rundliche Räume vorhanden sind und die Netzhaut eine Lücke aufweist” 4. Arbeits Diagnose- Differential-Diagnose
Zähle mögliche Diagnosen auf, die Dir einfallen. Welche weniger? Was selten ist, ist selten. Frage Deine Kollegen. Lade Bilder auf getoct.com hoch und frage Deine getoct friends. 5. Diagnose, Synopsis
Welche Diagnose passt am besten zum klinischen Bild und den anderen Resultaten? 6. Verlauf
Was passiert während der nächsten Zeit?
Der grösste OCT-Fehler ist die Frage, ob das OCT zur Diagnose passt anstelle von “passt die Diagnose zum OCT?”
Présentation
Pour la plupart des gens, la perte de vision sévère ou cécité est pires que le cancer ou même la mort. Pour la plupart des patients, il y a maintenant des options diagnostiques et thérapeutiques afin d’éviter la perte visuelle. Un ophtalmologiste peut évaluer les changements pathologiques de l’œil seulement. En OCT (tomographie en cohérence optique) il y a un outil disponible avec lequel dans un court laps de temps, on peut mesurée complètement inoffensif l’oeil avec précision. Il n’est pas nécessaire de toucher l’œil. On peut examiner aujourd’hui le plus petit niveau de l’œil.
Qu’est-ce OCT?
OCT est synonyme de «tomographie par cohérence optique” et est similaire à une échographie. Seulement, au lieu d’ondes sonores, une lumière laser spécial et totalement inoffensif est utilisée. La lumière (optique) de laser est constitué d’ondes de lumière cohérente (cohérence) pour produire des images en coupe (tomographie).
Comment peut-on examiner avec OCT?
Souvent, la cornée avant la mesure OCT est traité avec un collyre hydratant. Le patient garde ses vêtements, s’assied à l’appareil, basé sur son menton et son front contre un support. Il regarde ensuite dans l’appareil, où généralement une croix de lumière apparaît à fixer. Il y aura deux ou trois bons cligna pour préserver l’humidité cornée et de tenir à disposition pour une mesure idéale. L’examinateur compte sur trois, presses à la fois d’accord sur un bouton pour déclencher la mesure et le patient ouvre les yeux en place. Une mesure prend quelques secondes. Cycles de mesure prendent entre 1 à 10 minutes, selon la question. Habituellement les deux yeux sont examinés afin de permettre une comparaison entre les yeux. Les images sont imprimées et expliqué en détail aux patient et donnée. Par ailleurs, les images sont stockées et disponibles pour les enquêtes ultérieures.
Comment fonctionne un OCT?
L’OCT est sans doute une technologie laser, mais l’énergie du laser appliquée est très faible, de sorte qu’aucun dommage ne peut être attendue en principe. La mesure est sans contact et ne prend que quelques minutes, peut souvent être dispensé sans dilatation de la pupille, ce qui est de certaines formes de glaucome à l’avantage, car une augmentation soudaine de la pression intraoculaire peut être évitée. Les patients avec la situation de l’œil sec, dans de rares cas ont une sensation de sécheresse renforcée. Ceci peut être détecté par un ophtalmologiste et traité. L’OCT est plus convivial pour le patient, parfaitement sûr et indolore!
Lorsque l’OCT est un moyen utile?
Une tâche importante de l’ophtalmologie contemporaine, et que les maladies sont découverts à un stade précoce avant que des dommages irréversibles ont été subis. Ainsi, le traitement approprié et le succès sera surveillée de près. Une allégation de santé est limité et suivi en temps opportun, les coûts sont réduits.
Les problèmes oculaires suivants sont détectés tôt avec OCT:
Glaucome
Le glaucome ne veut pas dire seulement «augmentation de la pression intraoculaire», car il y a des types particuliers de glaucome avec une pression de l’œil «normale». Parce que le glaucome est un groupe de maladies dont la caractéristique commune est l’atteinte du nerf optique. Caractéristique d’un mort du tissu de fibres nerveuses est trouvé aux nerf optique qui apparaît pâle et creusé et la rétine qui disparaît dans l’épaisseur. Elle est également parlée par le ” voleur invisibles”, parce le glaucome détruit très lentement le nerf optique et la victime jusqu’à très tard remarque un dommage permanent. Une réduction rapide de la pression intraoculaire peut être le stop de la maladie. Un diagnostic très précis et de suivi permet le mesure du champ visuel et, plus récemment, dans les OCT, qui compare les valeurs de référence appariés selon l’âge avec les valeurs mesurées sur le patient et permet un diagnostic plus tôt.
Diabète
Le diabète non traité peut mener à la cécité. En plus d’un trouble circulatoire survient dans les cas avancés, une accumulation de liquide (œdème maculaire) dans la rétine. L’épaisseur de la rétine peut varier en fonction de la teneur en sucre et la pression artérielle. Avec OCT, on peux mesurer l’épaisseur de la rétine et contrôler très précisément le traitement.
Dégénérescence maculaire liée à l’âge, brièvement AMD
Liées à l’âge, des dépôts de produits métaboliques dégénérescence mènent sur le terrain de la macule, dans le centre de la visionet döclanche une perte substantielle. La capacité de lire peut être perdu, une cécité survient pratiquement jamais. Il existe deux formes: la fréquente sèche (atrophique) et le rare, mais rapidement progressive humide (exsudative) forme. Environ 10 pour cent des patients souffrent de la version humide. Une documentation précise de l’étendue et la localisation est possible avec OCT.
Rétinopathie séreuse centrale (RCS)
RCS est une maladie de la rétine chez les personnes à l’âge de 20 et 50. RCS est observé avec un stress modéré chronique, les corticostéroïdes, après une transplantation d’organe, les maladies auto-immunes ou de grossesse. Grâce à un petit écart dans la couche pigmentaire de liquide se produit sous la couche de cellules sensorielles de la rétine. La perte de vision des patients préavis, le flou, des lignes ondulées. Habituellement, la maladie est limitée et un retour après deux à trois mois suit, avec peu de cicatrices des défauts de vision des couleurs peuvent arriver. Merci à OCT, le cours sera déterminée exactement.
Trous maculaires
Créer un trou dans le centre de la vision, alors bien sûr la lecture est difficile. Selon l’aspect de l’orifice, un autre traitement est recommandé. Avec le OCT on peut décider à ce sujet et fait une classification précise.
Fibroplasie épirétinienne, la traction rétinienne
L’intérieur de l’œil n’est pas creux et vide, mais rempli d’un gel relativement transparent qui est entouré par une enveloppe qu’un ballon et entrecoupées de plusieurs chambres, appelée le vitré. Le corps vitré est proche de la rétine. Il se rétrécit avec l’âge et peut développer des forces de traction sur la rétine (traction) et ainsi conduire à incomplèt ou approfondie trous rétiniens (foramen). Il peut également venir à une formation des fibres sur la surface de la rétine (fibroplasie), qui peuvent fausser la rétine et de l’enflure (œdème maculaire).
Liste OCT positive
■ Changements maculaire (AMD, DME, inflammation, troubles circulatoires, l’occlusion des vaisseaux, dégénérescence maculaire congénitales et acquises)
■ Le glaucome et la détection précoce (couche de fibres nerveuses, RNFL)
■ maladies de la rétine (uvéite, troubles circulatoires, l’occlusion des vaisseaux)
■ traction vitréorétinienne
■ lésions du nerf optique
■ perte imprécise de l’acuité visuelle
■ la morphologie de la cornée, la topographie cornéenne, diagnostic du segment antérieur
Liste OCT négative:
■ tumeur de la rétine (naevus, angiome, mélanome)
■ processus choroïdienne
■ pathologie sclérale ou orbital
Introduction For most people, the severe vision loss of visual acuity or blindness are the worst imaginable fate that often more feared than cancer or death. But for most patients, there are now safe diagnostic and therapeutic options in order to avoid visual loss or blindness. An ophthalmologist can only estimate the extent of pathological changes of the eye usually. But with OCT (optical coherence tomography) he has a new tool available which allows him in a short time, a completely harmless examination of the eye. It is not necessary to touch the eye. A novel insight into the smallest levels of the eye is possible.
What is OCT?
OCT stands for “optical coherence tomography” and is similar to an ultrasound. Only instead of sound waves, a special and completely harmless laser light is used. The laser light consists of coherent light waves (optical) to produce cross-sectional images (tomography).
How is OCT done?
Often the cornea prior to the OCT measurement is treated with hydrating eye drops. The patient keeps his clothes on, sits down at the device, based on his chin and his forehead against a support. He then looks into the device, where usually a cross of light appears to fix. The patient will be asked to blink sometimnes to keep the cornea moist and to prepare for an ideal measurement. The examiner counts on three, presses at the time agreed on a button to trigger the measurement and the patient opens his eyes wide up. The measurement takes a few seconds. Measurement cycles take between 1-10 minutes, depending on the question. Usually both eyes are examined in order to enable a comparison. The images are printed, explained to the patient in detail and given. Moreover, the images are stored and are available for subsequent examinations.
OCT is harmful?
OCT is probably a laser technology, but the applied laser energy is very weak, so no damage can be expected in principle. The measurement is contact-free and only takes a few minutes. OCT can often be performed without pupil dilation, which is in certain forms of glaucoma an advantage, since a sudden increase of intraocular pressure can be prevented. Patients with dry eye report, in rare cases an increased feeling of dryness. This can be detected by an ophthalmologist and treated. OCT is patient-friendly, completely safe and painless!
When is OCT useful?
An important task of contemporary ophthalmology is to determine a diseases at an very early stage before irreversible damage has occurred. Thus, the appropriate therapy is initiated, and the success will be monitored closely. A damage is restricted and follow-up costs are reduced.
The following eye problems are detected early with OCT:
Glaucoma
Glaucoma does not mean only increased intraocular pressure, because there are special types of glaucoma with a nearly “normal” eye pressure. Glaucoma is a group of diseases whose common feature is the damage to the optic nerve. Characteristic for glaucoma is a death of nerve fiber tissue and the optic nerve head appears pale and hollowed out and retinal thickness disappears. It is also spoken by the “invisible” thief, because glaucoma progresses very slowly and thus secretly destroys the optic nerve and the patients notices very late a permanent damage. With eye drops the intraocular pressure can be lowered to stop retinal loss. A very accurate diagnosis and follow-up allows the measurement of the visual field and, more recently, the OCT: it compares the age-matched reference values with the values measured on the patient and allows an earlier diagnosis.
Diabetes
Untreated diabetes can lead to blindness. In addition to a systemic disorder in advanced cases, an accumulation of fluid (macular edema) in the retina occurs. The retinal thickness can vary depending on sugar content and blood pressure. With OCT one can measure the retinal thickness very precisely to control the treatment.
Age-related macular degeneration, briefly AMD
In age-related macular degeneration deposits of metabolic products lead to a substantial loss to the center of reading. The reading ability can be lost, but a blindness occurs practically never. There are two forms: the frequent dry (atrophic) and the rare but rapidly progressive wet (exudative) form. About 10 percent of patients suffer from the wet version. An accurate documentation of the extent and localization is possible with OCT.
Central serous retinopathy (CRS)
CRS is a retinal disease and occurs in people between 20 and 50 years. CRS is observed with moderate, chronic stress, corticosteroids, after organ transplantation, autoimmune diseases or pregnancy. Through a small gap in the insulating pigment layer fluid accumulates between the sensory and outer cell layer of the retina. The patients notice vision loss, blurring, wavy lines. Usually the disease is limited by itself all the way back after two to three months, little scarring can lead to permanent vision defects or color vision problems. Thanks to OCT, the course will be determined exactly.
Macular holes
With a hole in the reading center, of course reading is difficult.
Depending on the appearance of the hole, another treatment is recommended. With the OCT one can decide about the therapy and made an accurate classification.
Epiretinal fibroplasia (ERFP), retinal traction, pseudo-holes
The interior of the eye is not hollow and empty, but filled with a relatively transparent gel-like material that is surrounded by a balloon-like envelope and interspersed with several chambers, called vitreous. The vitreous is close to the retina. The vitreous shrinks with age and can develop tensile forces on the retina (traction) and thus lead to incomplete or thorough retinal holes (foramen). It can also come to formation of fiberboards on the retinal surface (fibroplasia), which can distort the retina and lead to a retinal swelling (macular edema).
