GLAUCOMA Flashcards
increased pigmentation of angle
- PDS (uniform)
- PXF (patchy, sampaolesi)
- surgery
- trauma
- inflammation
- hyphema
- angle closure
causes of arcuate defect
glaucoma
AION / NAION
disc drusen
BRVO / BRAO
optic nerve pit w/ serous detachment
optic nerve coloboma
myelinated nerve fibers
optic neuritis / C-R’itis
retinoschisis
retinitis pigmentosa
papilledema
laser
high myopia
shock optic neuropathy
melanocytoma
visual field defect with clear cut edge
Hyperope Rx (+6.00D on 30-2)
Brain surgery removed
Absolute defect in retinoschisis
RP
enlarged blind spot
Structural causes
- Large disc/megalopapilla
- ONH drusen
- High myope
Eye disease
- Early papilledema
- Chronic papilledema
- Early glaucoma
- AIBSE (acute idiopathic B.S. enlargement)
- MEWDS
- diabetic or hypertensive papillitis
large disc > 4.09 mm2
physiologic
megalopapilla
high myopia
morning glory/pits
congenital glaucoma
small disc < 1.29 mm2
physiologic
high hyperopia
hypoplasia
drusen
thickest rim and most susceptible to glaucoma
thickest: I>S>N>T
most susceptible: I>S>T>N
K spindle
Age
PXF
PDS
Trauma
Surgery
Hyphema
Uveitis
Melanoma
Nevus of Ota
hyphema in an adult
Systemic causes
- Bleeding diathesis – anemia – sickle cell
- Anticoagulation
- Leukemia / lymphoma
- Behcet’s / HLA-B27
Local causes
- Iris tumour
- NVI
- HSV / VZV
- Fuchs
- ocular surgery
- UGH
- trauma
causes of ectropion uvea
ICE
AR
uveitis
PPMD
NF-1
NVG
epi downgrowth
isolated congenital anomaly
causes of epi down growth
ECCE #1
PK
Glaucoma sx
Penetrating trauma
risk factors for OAG
IOP
Age
Race
FHx
thin CCT
(C:D, VF severity)
Soft: DM / myope / CRVO/ HTN/CVD
ass systemic diseases: sleep apnea, myopia, DM, BP, CRVO, migraine, thyroid, raynauds, hyperlipid
Risk factors for NTG
Female
Migraine
Disc H
Vasospasm / Raynauds
Smoking
risk factors for ACG
I Age
Race
Sex (F > M)
Hyperope
FHx
ocular biometrics
blacks vs white disease
3 – 6x white OAG
earlier onset (1 decade)
HIGHER IOP
Larger c:d ratios / ONH
More BLIND (8x increased risk)
Thinner cornea (CCT thin = underestimate)
causes of increased EVP
- AVM - SWS, AV fistula- carotid or dural cavernous sinus, orbital varix
- Venous obstruction -
- local - thyroid, retrobulbar tumour, CS thrombosis, orbital vein thrombosis
- systemic - CHF, SVC syndrome
- idiopathic
blood in schlemms
artifact of goniolens occluding episcleral veins
high episcleral venous pressure
- idiopathic uveal effusion syndrome
- Sturge-Weber
- carotid-cavernous fistula
- dural-cavernous fistula
- orbital AV fistula
- retrobulbar tumor
- mediastinal tumor
- superior vena cava obstruction
low IOP
- inflammation
- hypotony
- following trabeculectomy
normal eye
unilateral IOP rise with uveitis
Trabeculitis (stellate KP – HSV / VSV / FHI / Posner / toxo / sarcoid / syphilis)
Lens-related (lytic / anaphylactic /particle)
UGH
Other: JRA (20%)
HLA-B27 (Reiter’s)
Lyme
TB
VKH
Behcet’s
Causes of NVI NVA
DDx - NVI/NVA - 97% d/t ischemia – 3% d/t inflammation d/o
ocular vascular dz
- DR (30%)
- CRVO (30%) – 90 day glaucoma
- CRAO / BRVO
- ROP / FEVR / Eales
- sickle cell
- Coats disease
- PHPV
- syphilitic vasculitis
- sarcoid
- anterior segment ischemia
other ocular dz
- ocular ischemic syndrome
- chronic uveitis
- chronic RD
- endophthalmitis
- Stickler syndrome
- retinoschisis
Intraocular tumors
- uveal melanoma
- metastatic carcinoma
- RB
- reticulum cell sarcoma
ocular therapy
- radiation therapy
- postvitrectomy in DR
systemic vascular dz
- carotid occlusive dz
- carotid artery ligation
- CCF
- GCA
- Takayasu (pulseless) disease
Trauma
Rare causes FHI, Uveitis, Iris melanomas, PXF
ONH analyzers
HRT (Heidelberg Retinal Tomogram)
– confocal scanning laser- tomographic slices are manipulated to form a 3D construct, can calculate NFL measurements
GDx (Glaucoma Diagnostix)
– scanning laser polarimeter- takes advantage of hte birefringent properties of hte rNFL arising from parallel microtubules - as light passes through NFL polarization state changes, deeper layers of retinal tissue reflect light back to the detector where the degree to which polarization has changed can be recorded.
– polarized lite shift measures relative NFL thickness
OCT (Optical Coherence Tomography)
– interferometer; low coherence lite
– high resolution (10 um)
– measures absolute NFL thickness
when to treat with cycloplegic
Pseudophake /aphake
ACIOL pupil block
Microspherophakia (pulls lens back – LIE on BACK!)
Malignant glaucoma
Post-SB (band too tight!) – pushes L-I back
Uveitis (posterior synechiae)
Cyclodialysis cleft (low IOP) – it closes it
congenital glaucoma problems
whole eye:
- anterior segment dysgenesis (A-Reigers / Peters)
- nanophthalmos / microphthalmia
- high hyperopia
cornea
- sclerocornea
- cornea plana
- megalocornea
- microcornea (closed angle)
- aniridia: 50% get glaucoma
lens:
- microspherophakia
- dislocation DDX
retina / vitreous:
- PHPV / ROP
nerve:
- morning glory
blind painful eye
Make sure correct dx – r/o malignancy! (B-scan)
Atropine / Pred Forte
Cauterize cornea
Retrobulbar EtOH / chlorpromazine (lasts 6 mos – 1 year & immediate results)
Cycloablation
! Laser (diode / trans-scleral YAG)
! Cryo
Enucleate / eviscerate (DEFINITIVE!)
How do you define progression
- need at least two confirmatory tests
- in CNTGS used thresold testing - If two or more points within or adjacent to an existing scotoma worsened by at least 10 dB or three times the average of the short-term fluctuations= progression if seen on two further fields… may not apply to Swedish Interactive Threshold Algorithm (SITA) visual fields for two reasons. First, the short-term fluctuation is not measured in the SITA program. Second, a 10-dB change in full threshold may not be equivalent to a 10-dB change in a SITA field.
- In EMGTS for the indication of likely progression, used the Glaucoma Progression Analysis software requires that three consecutive visual field tests contain three or more identical points that have changed at a statistically significant level
- total dev plot two spots that are less than 5 % suspicious for defect…or one spot that is less than 1% repeat
when are you worried about neuro disease
- optic nerve pallor out of proportion to degree of cupping
- VFD greater than expected based on amount of cupping
- VF patterns not typical of glacuoma
- unilateral progression of VFD despite equal IOP
- decreased visual acuity out of proportion to the amount of cupping or field loss
- color vision loss (esp in red green)
OHTS who to treat
- highest risk were those with IOP greater than 25.75 and CCT < 555 (36%)
- patietns with CCT > 588 and IOP < 23.75 had the least risk (2%)
Contraindications to SLT
ABSOLUTE
- uveitis
- congenital/developmental glaucoma
- ICE/NVG/PPMD
- PAS
Relative:
- Angle recession
- lack of effect in fellow eye
- advanced glaucoma
Cx of ALT/SLT
- IOP spike 1-4 hours after treatment
- IOP increased requiring filtering sugery
- hyphema
- PAS
- rarely - corneal opacity
RECALL risk factor for IOP spike after ALT/SLT: higher energy level, 360 degree treatment, posterior placement of burns, more heavily pigmented angle
Mechanism for steriod response
- increased extracellular matrix layed down in TM (increased GAGs)
- decreased migration of macrophage to clear out extracellumar matrix
- swelling of TM
- inflammatory cells blocking TM
RECALL: risk factors for IOP response: known POAG, family history, age, DM, mypopia
RECALL: steriods take 4-6 weeks on avg to get response, IOP should decrease by 2 months
Risk for re bleed
- Hypotony or increased IOP
- 50% or greater hyphema
- systemic HTN
- ASA
- black
Recall: 5-10% chance of re bleed, with re bleed 50% change increased IOP, 5-10% chance of glaucoma with >180 degrees of angle recession
Mechanisms of angle closure
PUSHING
pupillary block, aqueous misdirection, ciliary body swelling, anteriorly located ciliary processes, choroidal swelling, serous or hemorrhagic detachments or effusions, posterior seg tumours, contracting retrolental tissue, anteriorly displaced lens, encircling bands
PULLING
contraction of inflammatory membrane or fibrovascular tissue, migration of corneal endothelium (ICE, PPMD), fibrous ingrowth, epi ingrowth, iris incarceration
bleb failure risks
- ant seg NV
- black race
- aphakia
- young
- prior CE IOL
- uveitis
- prior failured filtering procedures
risk factors for endophthalmitis
- bleb leak, inferior or nasal bleb, high bleb
- intraoperative MMC
- conjunctivitis/blepharitis/ NLD obstruction
- upper respiratory infection
- diabetes
- trabeculectomy alone compared to combined procedure
- chronic antibiotic us
- CL use
- male
- young
risk factors for blebitis
- bleb leak
- intraoperative MMC
- antibiotic use after the postoperative period
- high axial length
- conjunctivitis
- upper respiratory infection,
- winter season
complications of filtering surgery
early
- infection
- hypotony
- shallow or flat AC
- aqueous misdirection
- hyphema
- transient IOP elevation
- CME
late
- leakage or failure
- cataract
- blebitis
- endophthalmitis
- dysesthetic bleb
- bleb migration
- hypotony
- maculopathy
- ptosis
- plate migration
- tube occulsion
- eyelid retraction
