assignment 1 Qs Flashcards
Considering the site of tissue ablation in each type of refractive surgery, which procedure would you recommend for a myopic patient with EBMD/ABMD who wants refractive surgery?
PRK, since the epithelium and Bowman’s layer will be removed in the process of the procedure.
What is the best refractive surgery procedure for a 23 year old male patient with a refractive error of: -4.00-2.00x090 OD, OS?
LASIK
What is the best way to remove a bandage contact lens without causing an epithelial abrasion in a post-PRK patient?
The best way is to pull the lens down off the cornea to make sure it’s mobile then once its past the limbus then you pinch it off
What is the best refractive surgery for a pt that has corneal pachymetry readings less than 490 microns?
PRK
According to Dr. Findley, what measurements are needed on corneal topography for a patient to qualify for corneal refractive surgery?
Posterior float <40 microns; Difference of astigmatism between eyes <1.00 D; <1.50 D of irregular astigmatism in the central 3mm; <2.00 D of irregular astigmatism in central 5mm; Periphery >20 microns thicker than center.
55 year old Caucasian female presents to your office wanting to have the cataract within her right eye removed. The patient has been wearing toric SCLs for 10 years. Before cataract surgery can be performed, how long before surgery should the patient stop wearing her CLs?
Before cataract surgery, toric soft lenses should be removed for at least 2 weeks. Spherical soft lenses should be removed for at least 1 week, and RGPs for at least 4 weeks.
You have a 4 day post-op LASIK patient in your exam chair. There were no complications during surgery. SLE shows central corneal opacification with no inflammation. Manifest refraction shows a large hyperopic shift. What is your best course of treatment for this patient?
This is Central Toxic Keratopathy. There is no treatment, only time will heal it (in 6-9 months).
Which is considered the most important variable in IOL calculations, the axial length measurement or the anterior cornea measurement?
Anterior cornea because it is the most important surface, affecting both spherical power and astigmatism.
According to Dr. McWherter, how can a subconjunctival hemorrhage created during cataract surgery reduce the risk of endophthalmitis?
It allows WBCs to reach the incision site more easily
What type of patient qualifies for cataract surgery by most insruance standards
Someone who complains about problems with decrease VA with glare
Who is a good candidate for mono vision with cataract surgery
Patient who did well with mono vision when younger and has cataracts and ptosis as the only exam abnormalities
What patient is at highest risk for IOP spike after cataract surgery
Pigment dispersion and pseudoexfoliation patietns on 2 meds
Who is a potential multifocal IOL candidate
Self proclaimed perfectionist patient who believes he can live with the halos shown on the online multifocal simulator
Which of the following treatments has the lowest endophthalmitis rates after cataract surgery and is not disapproved by the FDA?
TriMoxi in the anterior vitreous during surgery with vancomycin in the AC
TriMoxi should be avoided in which of the following patietns
Patietns with levaquin allergy
Which of the following is true about laser cataract sx
The femtosecond laser creates a true circular capsulorhexis
What is the risk invovled with iris manipulation during cataract surgery
Increases post op inflammation
Your patient is wanting a multifocal IOL but in glare testing they see halos. They claim they would be okay seeing like that for the rest of their life. Would this be a contraindication to perform the cataract surgery with that specific IOL? Why?
This would not be a contraindication (in this case). The patient acknowledges the glare and is okay with living with it. If the glare were too much for the patient to deal with, another lens should be chosen prior to surgery
When performing a slit lamp exam on a patient for their 1 week post LASIK visit you notice full thickness undulating stromal folds. How would the surgeon correct these folds in order to prevent them from being permanent
This finding is called macrostriae. Since the patient has been 24 hours post op, the proper way to treat this is by removing the epithelium. If macrostriae were seen within 24 hours following surgery, the LASIK flap could be lifted and smoothed down
Regarding phakic IOLs, what is the vault and what is its purpose
It is to create space between the posterior surface of the IOL and the crystalline lens to allow adequate aqueous flow
According to Dr. Findlay, if you have a PRK patient that’s develops stromal haze, when would you expect the haze to fade away
You should expect stromal haze to fade in about 6-12 months
Name something that is usually not a mid to late complication of LASIK
Infectious keratitis. Onset is within the first 24 hours
What two conditions can mimic diffuse lamellar keratitis
Infectious keratitis and pressure induced stroma;l keratitis or PISK
When doing a pre op evaluation of the cornea for a patient who is wanting to have PRK, you notice a scar. The scar appears to be superficial to the flap interface. Is PRK still a good surgery option or should your patient pursue other surgical options?
PRK is still an option for this patient because it may remove the scar since it is superficial
What are 4 relative contraindications of multifocal IOLs
Latent phorias
Threat of disease that may affecte central vision
Dry eye
Perfectionist patietns
When examining the conjunctiva before and after refractive surgery, why would you use lissamine green?
To monitor if dry eye has worsened following the refractive surgery
You notice mictrostriae on your post LASIK patient. What must be done to help this patient? Does anything have to be done at all
This Econ’s from inital flap malpositiojn or slippage so you must repair it quickly before it becomes permanent. Lift and refloat the flap and stroke it down. If greater than 24 hours hours the epithelium must be removed
What is the difference between keratoconus and form fruste keratoconnus
Keratoconnus is inferior corneal thinning of both eyes and form fruste keratoconnus is inferior thinning of one eye, but not the other. This is due to eye rubbing of only one eye. The treatment for keratoconnus can involve scleral CL or corneal collagen cross linking, whereas form fruste keratoconnus is not progressive, so there is no treatment necessary for it
Post LASIK you see epithelial ingrowths moving toward center of the cornea with a decreased VA due to irregualr astigmatism. Would you treat, if so, how?
Yes, you would want to treat this patient due to the complain of decreased VA. The treatment would be to lift the flap back up, scrape the epithelium from the stromal bed, respoition the flap and then apply a bandage CL on the eye
What is proper procedure if a buttonhole develops in the flap intraoperatively during LASIK
stop the procedure and replace the flap, then let the flap heal for 3-6 months and then do PRK
What are 6 potential complications of refractive lens exchange?
Wound leak, IOP spike, endophthalmitis, TASS, CME, and RD
When performing KRS on a mixed astigmat with a Rx of +1.00 -2.00 x 180 OU, how must you treat the patien
For a mixed astigmatism treat one meridian as simple hyperopic astigmatic and the other as simple myopic astigmatism. In this instance if would be Plano -1.00 x 180 and Plano +1.00 x 090
A post cataract patient with a small axial length presents with high IPO and shallow AC depth both centrally and peripherally. What is the likely diagnosis and how can it be treated
Aqueous misdirection Three treatment options 1. Cycloplege (the patient typically would be for the cataract surgery itself) 2. YAG laser to anterior hyaloid 3. Pars plana vitrectomy
SMILE, a refractive surgery that uses femtosecond laser to make an intrastromal laser cut has A similar outcome to LASIK. What is one benefit of SMILE compared to LASIK and why
Less risk of fry eye symptoms, in incision takes place withi nthe cornea without the need for a larger corneal flap resulting in less damage to corneal nerves
Regarding a patient with Fuch’s who shows prominent bullae, what surgical procedure should be performed ASAP
Descemets Membrane Endotherlial Keratoplasy (DMEK)
What is the difference between a posterior polar cataract and PSC
Posterior polar cataract has sharply demarcated borders
Why should you never polish a posterior polar cataract
The capsule can rupture
What corneal procedure has the highest rejection rate in the first 2 years: PL, DALK, DSAEK, or DMEK?
PK has the highest rejection rate in the first 2 years with 18%
DALK 4%
DSAEK 5-12%
DMEK 1%
In terms of corneal transplant methods, which method does not lead to corneal astigmatism
DMEK
Descemets membrane endothelial keratoplasy
What are the two post op stages in penetrating ketratoplasty (PK)? What are the risks with each stage?
Epithelialization is the first stage and takes 1-2 weeks to occur. Patients run the risk of rejection and endophthalmitis
Stromal healing is the second stage and takes 1 year. Patients do run the risk of infection from loose suture and rejection
Which corneal transplant procedure is MOST useful for case of granular dystrophy that compromises a patients VA
Given the granular dystrophy is a stromal dystrophy, a PK would be indicated
When you have a patient with a flat anterior chamber and high IOP what are two dx that should be suspected
Angle closure and malignant glaucoma (aqueous misdirection)
What is the official treatment for malignant glaucoma
Pars plana vitrectomy
What 3 tests are required at the initial post op visit within the first 3 days after cataract surgery
VA
IOP
Slit lamp
DALK and OK have simialr stages and treatment. However, what are some of the slight differences with DALK?
DALK has:
- less risk of rejection
- can taper steroids earlier and remove sutures earlier
- less blunt trauma risk
What is the typical schedule of antibiotic, steroid, and NSAID drops following cataract surgery
ABX: q1h first day, TID x 3 more days
Steroid: QID tapered 1 gt per week
NSAID: dose depends on type
A 45 year old male comes in in wtih confluent corneal guttata, what are possible treatment options
DMEK, if they choose to defer surgery, monitor every 6 months or sooner if symptoms worsen
A patient reports for a post opt surgery with an epithelial defect. The surgical note states that TriMoxi was used during the procedure. In addition to BCL, what type of medication do you need to Rx
An abx
You have a patient that comes in after cataract surgery. On examination you find their pressures to be 60mmHg OU. you recheck pressures after a couple minutes and once again find it to be 62mmHg OU. Would you want to burp the wound> why
Yes. You would want to burp the wound and recheck pressures after 30m. If pressures are still high, burp again and repeat every 30m until pressure stops rebounding
When would you want to burp for post op cataract surgery
Depending on what the pressure is before you begin burping, you will need to continue doing so until you reach a desired IOP
What does the burping technique consist of
Numbing, betadine, abx drops, lid speculum, then calmly press the sclera adjacent to the wound to release pressure, then give IOP drops
With PK/DALK, what can be used to erase high astigmatism once healed and is referred to as the silver bullet
Toric IOL once healed is your silver bullet
How often do you burp a patients eye with IOP of 60mmHg
As often as needed every 30-40m until IOP is consistently within normal limits
Which topical IOP drop should be avoided in patietns with corneal edema
Cosopt
What is a concern of prolonged inflammation after cataract surgery
CME
What is a sign of endophthalmitis
Vitreous cells
What is true of the femtosecond laser during cataract surgery
It creates a true circular capsulorhexis
What are some potential causes of rebound inflammation
- greater inflammatory potential/history of uveitis
- iris manipulation during surgery
- retained hidden lens fragment (check angle and sulcus with gonio)
What is true about a white cataract
They are often pressurized and need to be decompressed to prevent the “Argentinian flag sign”
An exposed blue suture or haptic (eroded through conjunctiva) is
Simialr to an exposed glaucoma tube; needs abx and return to surgical practice
Which patietns should be told they are at higher risk of complications during cataract surgery, higher risk of needing a second surgery, and should be referred to a more experienced surgeon
Posterior polar cataracts
Phacodonesis
White cataracts
What is the best treatment for an eye that had high IOP and very shallow peripheral and central AC after cataract surgery, with no choridal hemorrhage?
IOP drops and cyclo
LPI
Something about posterior hyaloid membrane
Signs of endophthalmitis include
Injection
Vitreous cells
Hypopyon
Not SPK
You see an hypopyon on POD 1, what is the most likely dx
TASS
Which surgery has the fastest recovery
DMEK
What is the correct order of surgeries in increasing order concerning the amount of host tissue removed
DSAEK=DMEK
What is the best treatment for Fuchs
DMEK
What can cause of edema in a transplant
- endothelial injection (acute immune attack)
- bare stroma exposed to Aq humor
- bare stroma exposed to isotonic tears
- chronic graft failure (endo attrition)
How do you tell the difference between a hypopyon and a pseudohypopyon
The hypopyon is flat and the pseudohypopyon is layered. The hypopyon is infection or inflammation and the pseudohypopyon is not inflamed
A 60 year old AA male presents to your office for his post op cataract evaluation. You checked the patients IOP and you noticed an IOP spike. What should you do next and what could have caused that
You should perform gonio to examine the TM and see if it was unhealthy, which would habe caused the patient to have had a natural propensity for a IOP spike
Refractive surprise tends to occur due to which factors and how would you explain this occurrence to the patient
The eye shifts during healing which may be due to unique biology of the individuals eye such as posterior corneal astigmatism. The dr should never blame the surgeon but explain that every eye and person is difference and sometimes it just happens
What is the risk for posterior capsule opening
Vitreous traction
Posterior cataract fragment
Limited capsule support
IOP spike
What is the treatment of choice when a Fuchs patient presents with fibrosis and counting fingers VA
penetrating keratoplasty
Regarding aqueous misdirection (malignant glaucoma), what are the 4 most common differentials
Wound leaks
Choroidal effusion
Angle closure
Choridal hemorrhage
What is the silver bullet to erase high astigmatism in PK/DALK
Toric IOL once its healed
What is the difference between PRK and LASIK
In LASIK, a thin flap is created in the Cornea by a microkeratome or femtosecond laser. The flap is lifted to expose the underlying corneal tissue and is then replaced after the cornea is reshaped by an excimer laser.
In PRK, the epithelium is removed and completely disregarded before the underlying corneal tissue is reshaped with an excimer laser.
This is the main difference.
What is an advantage of DMEK as compared to PK?
Descemets membrane stays intact with DMEK as opposed to PK where you have bare stroma. This also allows for less edema in DMEK.
What type of corneal transplant provides the BCVA and lowest percent of tissue rejection?
DMEK
Why does PK have such a high rate of rejection at 18%?
Because it replaces the endothelium and not just the stroma. Foreign endo is most likely to cause rejection.
What is the #1 lost ophthalmic lawsuit?
The most commonly lost ophthalmic lawsuit is due to unmonitored steroid-induced glaucoma damage. As a side note, in the ophthalmology world, doctors win 90% of the cases brought against them.
What are the two post op stages of a penetrating keratoplasty? And how long do each of the stages last?
Epithelialization and stromal healing. Epithelialization takes 1 day to 2 weeks and stromal healing takes 1 year (because sutures take a long time).
Why is it bad to have loose sutures?
Increased risk of an infection!
What is the most important step to remember BEFORE removing sutures on the eye?
Apply antibiotics and wait
What are indications for a Deep Anterior Lamellar Keratoplasty (DALK)?
Stromal Disease with a healthy endothelium!
Why do we want to keep the BSCL and antibiotic on the cornea for 1-3 months after the epithelium has healed?
We should treat PK patients as though they are neurotrophic then send back to the surgeon if an epi defect develops.
You are about to do a corneal transplant on your patient with Fuch’s Dystrophy. You decide you want to do a DSAEK transplant. How would you explain to your patient the difference in DSAEK vs. DMEK (regarding the corneal components).
Both procedures include the same corneal layers except DSAEK does NOT include the stroma!
How is DALK different than PK?
The healing process is different. The stitches can be removed in 8 months and there is less risk with blunt trauma with DALK.
What is the most likely the cause of new corneal edema that resolves with steroids after a transplant as opposed to not resolving with steroids?
Edema that resolved with steroids was rejection. If it failed to resolve, it it may be endothelial attrition.
What finding in a Fuch’s patient indicates the need for surgery as soon as possible?
Bullae
What layers of the cornea are removed and replaced with a deep anterior lamellar keratoplasty?
Epithelium, Bowman’s, and stroma.
After a Penetrating Keratoplasty, when should the patient wear goggles?
When participating in sporting events and when sleeping.
How long does a patient have to lay for after a DSAEK?
24 hours
What procedure has the same indication as DSAEK? And of the two, which is more difficult with ACIOL, PPV, tubes, large iris defects, etc?
DMEK has the same indications but is more difficult compared to DSAEK.
At what time of day is the edema initially worse in Fuchs?
AM
What is the difference between PRK and LASIK
In LASIK, a thin flap is created int he cornea by a micorkeratome or femtosecond laser. The flap is lifted to expose the underlying corneal tissue and is then replaced after the cornea is reshaped by an excimer laser.
In PRK, the epjtelrium is removed and completely disregarded before the underlying corneal tissue is reshaped with an excimer laser
If a patient has FUchs and presetns with guttata but not bullae, should they be referred to surgery, and if not, when should their follow up be?
Surgery not needed. Instead, the follow up should be in 6 months or sooner if symptoms worsen.
If guttata are confluent, push for elective DMEK if they qualify
How long does it take for the corneal stroma to heal after a penetrating keratoplasty
1 year
What does DMEK stand for
Descemets membrane endothelial keratoplasty
Morning blur in fuchs patient is likely indication of what
Bullae
Patient should be referred to surgery soon because morning blur is a sign that next stage in the fuchs patient is bullae
What is an early sign of bullae in a fuchs patient
Morning blur
What are some lifelong observations following PK that rewuire calling the surgeon ASAP
Redness, pain, blur (symptoms of loose suture, infection, or rejection)
Name three conditions that can be associated with corneal ectasia
Down syndrome
Floppy eyelid syndrome
Connective tissue diseases
What determines the severity of keratoconnus
Dr. Tenkmans preference is how severe the visual rehabilitation is
What methods can we se or recommend in order to prevent keratoconnus progression in our patients
Patients should be advised to avoid rubbing their eyes. We can treat any ocular allergies the patient may have bad use corneal crosslinking in order to make it easier for the patience to stop rubbing their eyes
What do you perform corsslinking on the worst eye first
You want to make sure the <1% risk of scarring doesn’t occur. If it does, it will most likely occur in the worst eye first
What is conjunctivochalsis
Excess folds in the conjunctiva
What is considered sub clinical DME progression
DME as a center point thickness (CPT) between 225 and 299um on a time domain OCT. progression is an increase in CFT of at least 50um and CPT of at least 300um
What are the 3 most common macualr problems
- AMD
- RVO
- DME
What structure of the retina can be used to determine if drusen is large enough to start a patient on AREDS 2 to decrease the risk of progression of dry AMD
Retinal venules can be used to determine if drusen size is large enough to have success with AREDS 2 to slow poregssion of dry AMD
Which type of patient benefits the most from AREDs vitamins
Patients with poor nutrition benefit the most from AREDS vitamins. Patients who already get the vitamins they need from their diet of leafy greens and vegetables won’t get much more of a benefit because ARMD cannot be managed only by increased amounts of vitamins once the necessary intake is met.
A 68 year old female presents to your clinic experiencing central vision loss. She also is a current every day smoker. You dilate the patient and discover what appears to be dry AMD. What is one of the first things you would inform the patient to do
Stop smoking— smoking can dramatically increase your risk of AMD getting worse and progressing to Wet AMD
What is most indicative of AMD treatment failure
The present of fluid on OCT
When was the first AntiVEGF treatment FDA approved
2011
How does AntiVEGF injections work to limit new BV
It binds to and stabilized the leaky retinal vessels increasing their structural integrity which allows them to not leak any of their contents into the retina
What are some systemic concerns with lucentis treatment and what type of patietns are at most risk of blindness?
With any anti-VEGF treatment there is an increase risk systemically of hemorrhages, cerebrovascular events, myocardial infarctions, and hypertension. Diabetic patients are at an increased risk of blindness secondary to their already compromised vasculature. These patients already have increased risk of heart attack, stroke, etc.
Which AntiVEGF drug has the best safety profile and why
Lucentis because it has the shortest half life
Which of the AntiVEGF injections commonly used in Wet AMD has the highest efficacy?
Eyelea
What os Ozurdex? What does it release? And what is it used to treat?
It is an intravitreal steroid. It has a much larger needled and injects a small pellet that allows the slow release of dexamethasone steroid over the course of a few months. It is used to treat diabetic macular edema.
What is the standard of care for treatment of CRVO and what are the risks involved?
Anti-VEGF. CRVO patients normally are at risk of 90 day glaucoma but with anti-VEGF treatment the patient is at risk for neovasular glaucoma for a longer period of time, sometimes up to a year.
How soon should you refer a patient who presents with a macular hole?
Surgery within 1 month
How soon should you refer a patient who presetns with an ERM
Within 1-2 months
How soon should you refer a patient that has a mac on RD
Same day, within 12-24 hours
How soo should you refer a patient for surgery that has a mac off RD
Next day, within 1-7 days of onset. Not as urgent because VA will be the same regardless of same day vs 1 week later
If a patient has recently eaten (within the last hour) what is the risk/complication that could happen during retinal surgery?
Patients have a possibility of asphyxiating on the food they have recently eaten due to complications/reaction to anesthesia used in retinal surgery
When advising a patient who will be having retinal surgery requiring a gas bubble, how long should you let them know that it will be in their eye and how it iwill affect their vision
Let the patient know the gas bubble will be in their eye for about 3 weeks. Their vision will be blurry for the first week and a half which is normal
A patient reports to your clinic for a follow up after a RD surgery. The patient was placed on accurate and is confused as to why they are taking the medication. What do you tell them?
According to Dr. Kitchens, this acne medication as well as other mediations such as methotrexate aid in halting a form of scar tissue formation called proliferative vitreoretinipathy (PVR)
Which AntiVEGF has the highest chance of baseline VA after one year of injections
Lucentis + deferred laser
What is the point of doing both a scleral buckle and vitrectomy instead of scleral buckle alone or vitrectomy alone?
scleral buckle and vitrectomy together have a 95% success rate at attaching the retina from the first surgery while each alone is about 85% success. And that is because the scleral buckle goes around the entire eye and reduces the risk of having additional tears while the vitrectomy decreases the chance of having a re-detachment.
It is preferred to do a scleral buckle in younger myopic patients, and vitrectomy on patients with multifocal IOL because we would not want to induce myopia from using a scleral buckle unless necessary.
What are possible risks of RD surgery
ERM
Diplopia
Ptosis
Axial length change
