眼科學-結膜疾病、角膜疾病(英文)

1、DISEASES OFConjunctiva 1ConjunctivaBulbar conjunctivaPalpebral conjunctiva(tarsal)Fornix2Conjunctival sign of inflammationPapillaeFolliclesChemosisMembrane true, pseudoScarSymblepharon3Chemosis4Membrane true, pseudo5Scar6Symblepharon7Bacterial conjunctivitis8Acute conjunctivitisStaph.aureus, H.aegyp

2、tius, H.influenzae, Strep.pneumoniae, Strep.pyogenes, P.aeruginosa, E.coli, C.piphtheriaeDuration3-4 wksRisk factor lid malposition, dry eye, chronic dacryocystitis, poor hygiene, eye prosthesis, topical steroidMild and nonspecific symptom16Viral conjunctivitisBenign, self limited, last longer than

3、bacterial conjunctivitisAlmost all acute follicular conjunctivitis, preauricular adenopathy17Epidemic keratoconjunctivitis(EKC)Adenovirus serotype 8,11,19,37Redness, FB sensation, tearing, photophobiaBilateral 50%Lid swelling, conjunctival injection, watery discharge, follicles, preauricular adenopa

4、thymembrane, pseudomembrane18Viral conjunctivitis19Epidemic keratoconjunctivitis(EKC)20EKCTreatmentPrevent transmissionSupportive treatment cold compress, topical artificial tear, topical vasoconstrictor, topical NSAID, topical steroid21Pharyngoconjunctival fever22Pharyngoconjunctival feverAdenoviru

5、s serotype 3,4,7Sign & symptom same as EKCKeratitis EKC, mild Pharyngitis, feverTreatment same as EKC23Acute hemorrhagic conjunctivitis24Acute hemorrhagic conjunctivitisPicornavirus enterovirus70, coxsackievirus A24Acute follicular conjunctivitis, subconjunctival hemorrhageKeratitis 6mm ,may involve

6、 over 75% of cornea. )82Cornea with keratoconus. Note the steeper curvature 83PATHOPHYSIOLOGYAll layers of the cornea are believed to be affected by KC, most notable features are the. 1. Thinning of the corneal stroma.2. Ruptures in the Bowman layer.3. Deposition of iron in the basal epithelial cell

7、s, forming the Fleischer ring. 4. Breaks in and folds close to the Descemet membrane result in acute hydrops and striae, respectively.84ETIOLOGYSporadic: Imbalance of enzymes within the cornea. This imbalance makes the cornea more susceptible to oxidative damage from compounds called free radicals,

8、causing it to weaken and bulge forward. Heredity Eye rubbingContact lenses wearHormonal change85Multiple imagesAssociated systemic diseasesfamily history of keratoconusseeing doubleGhost imagesflare or halos around lightsSensitive to lightVisual discomfortBlurring of visual acuityhistory86SYMPTOMSSt

9、art in puberty (in the teens) and may progress for the next 10 to 20 years.NearsightednessAstigmatismBlurred vision - even when wearing glasses and contact lensesGlare at night Light sensitivityFrequent prescription changes in glasses and contact lenses Eye rubbingDiplopia or polyopia.87Munsons sign

10、Corneal scarringCorneal striaeFleishers Ringchange in the astigmatic spectacle correction changeSigns88The Classic Signs Of KeratoconusSlit lampFleischers ring (an iron colored ring surrounding the cone)89Vogts striae (stress lines caused by corneal thinning) Apical scarring (scarring at the apex of

11、 the cone).90Corneal thinning: In advanced cases, the thinning of the central cornea can be seen on examination.91Munsons sign: Its an angulation of the lower lid during inferior gaze due to corneal protrusion92Photokeratoscope with normal round curvature Note the distorted pattern of the rings 93CO

12、RNEAL TOPOGRAPHY & PACHYMETRYMeasurements of corneal thickness and curvature The most commonly used approach is ultrasonic pachymetry. the probe must touch the corneal surface and topical anesthesia is thus required. Its accuracy is dependent on the perpendicularity of the probes application to the

13、cornea and reproducibility relies on precise probe placement on the corneal center.The Orbscan II corneal topography system (Bausch & Lomb) is an optical scanning-slit instrument that provides topographic analysis and pachymetric measurements of the cornea. This disparity between instruments can res

14、ult from their distinct methodologies. The noncontact Orbscan system measures the hydrated mucous component of the tear film over the cornea; contact ultrasonic pachymetry does not. Thus, Orbscan readings are higher than ultrasonic readings.94Ultrasound pachymetryOrbscan95TREATMENTSTo improve vision

15、 & to stop progressionGlasses or soft contact lenses in mild or early keratoconus.Rigid gas permeable lenses in the intermediate stages. Advancing keratoconus cant tolerate rigid contact lensNew treatments:Corneal ring -Intacts corneal rings (placing with the corneal stroma in the periphery of the cornea. The result is a flatter cornea and clearer vision.)C3R - Corneal Collagen Crosslinking with Riboflavin. Increasing collagen crosslinking within the cornea. Combined with Intacs to provide a combined effect and provide greater stability than one treatment alone.