Lasik Questions and Answers

Which statements are FALSE:

1. a + e
2. c + d
3. b + c
   b + c
4. d + e
5. None of the above

LASEK ...

1. LASEK, or Advanced Surface Ablation, was developed to improve safety and visual outcomes of laser refractive surgery.
2. There are < 15 potential complications that can occur in LASIK surgery.
   There are < 15 potential complications that can occur in LASIK surgery.
3. Major complications causing severe irreversible vision loss are not uncommon.
   Major complications causing severe irreversible vision loss are not uncommon.
4. Minor complications are frequent with LASIK.
5. The minor complications ultimately will have a subjective and objective effect on visual outcome.

---

Which of these statements is FALSE;

A flap too small can result from:

1. Keratome jam due to mechanical failure or tissue blockage.
2. A too flat corneal curve.
3. An incorrect choice of suction ring over which the Keratome can slide across.
4. The epithelium being too thick.
   The epithelium being too thick.

---

Which of the following statements are TRUE:

Microkeratome irregularities of the blade can cause:

1. Irregular flap shape
2. Variations in flap thickness
3. Variations in flap shape
4. Laceration or damage to the flap
5. High astigmatic visual problems
6. All of the above
   All of the above

---

Which statements are FALSE:

1. a + c
2. c + d
3. b + e
4. a + c
   a + e
5. b + d

A flap Buttonhole...

1. Is caused by the Intralase (or Keratome) laser cutting a flap too thick centrally.
   Is caused by the Intralase (or Keratome) laser cutting a flap too thick centrally.
2. Is caused by the Microkeratome (blade or Intralase) cutting a flap too thin centrally.
3. Causes epithelium to grow under the flap.
4. Can cause Corneal Melting which creates scarring and a poor visual outcome.
5. Is a special technique in LASIK to provide for a superior vision following laser surgery.
   Is a special technique in LASIK to provide for a superior vision following laser surgery.

---

Which statements are TRUE:

1. b + c + d
2. a + d + e
   a + d + e
3. a + b + d
4. b + c + e
5. a + c + e

1. A 'Free Cap' can be remedied by reattachment procedures and produces acceptable vision outcomes.
   A 'Free Cap' can be remedied by reattachment procedures and produces acceptable vision outcomes.
2. The corneal free cap is specialised collagen and so, unlike epithelium, is easily replaced.
3. The loss of free cap is a minor problem with no symptomatic outcomes.
4. Epithelial Abrasion results from Keratome injury caused by a dry corneal surface
   Epithelial Abrasion results from Keratome injury caused by a dry corneal surface
5. Epithelial Abrasion, whether small or severe, disturbs vision as well as causing disabling pain.
   Epithelial Abrasion, whether small or severe, disturbs vision as well as causing disabling pain.

---

Which statement is FALSE:

1. a
2. b
3. c
   c
4. d
5. e
6. f

Diffuse Lamellar Keratitis (DLK) is...

1. A condition unique to LASIK.
2. Inflammation within the flap interface.
3. Can be successfully treated with antibiotics & Vitamin C.
   Can be successfully treated with antibiotics & Vitamin C.
4. Can be directly caused by chemical or bacterial contaminants.
5. Can be indirectly caused by trauma of the flap.
6. In its most severe form, can cause devastating permanent vision effects including possible blindness.

---

Which of the above statements are true:

1. a + c + e
2. b + d + f
3. c + d + e
4. a + e + f
5. c + d + f
   c + d + f

Epithelial Ingrowth:

1. Is not associated with DLK.
2. Affects the centre of the flap.
3. Causes tear film problems, dry eye symptoms & night vision disturbances.
   Causes tear film problems, dry eye symptoms & night vision disturbances.
4. Can lead to melting of the cornea & flap.
   Can lead to melting of the cornea & flap.
5. Even if extensive, rarely causes permanent structural effects.
6. With Autolytic corneal enzymatic activity, may necessitate a corneal graft.
   With Autolytic corneal enzymatic activity, may necessitate a corneal graft.

---

Cross out the incorrect answer in each statement:

1. LASIK flaps in the early post-operative period are very weakly/strongly adhered.
   LASIK flaps in the early post-operative period are very weakly/strongly adhered.
2. The flaps only stay in place in the first few days due to tissue re-growth/osmotic pressure of the underlying cornea.
   The flaps only stay in place in the first few days due to tissue re-growth/osmotic pressure of the underlying cornea.
3. The position of the flap may be displaced through small/large trauma such as a poke with a finger or even squeezing of the eyelids.
   The position of the flap may be displaced through small/large trauma such as a poke with a finger or even squeezing of the eyelids.
4. After months or years, the flap always/never heals with the corneal stroma.
   After months or years, the flap always/never heals with the corneal stroma.
5. It is only the overlying epithelium/Bowman's membrane which anchors it
   It is only the overlying epithelium/Bowman's membrane which anchors it
6. Macrowrinkles result after immediate/delayed repositioning of a dislocated flap.
   Macrowrinkles result after immediate/delayed repositioning of a dislocated flap.
7. They will remain/disappear after repositioning.
   They will remain/disappear after repositioning.

---

Which statements are true:

1. a + c + d
2. c + d + e
3. a + b + d
4. a + b + e
5. All of the above
   All of the above

Subluxation or flap dislocation:

1. Is at its highest risk in the early post laser period.
2. If large, can cause severe pain and major visual loss.
3. If small, may go undetected by the patient, and thus allow time for permanent flap folds to form.
4. The flap never heals at the interface between the flap and the corneal bed.
5. The flap interface can be lifted up many years later and as such is a portal of entry of bacterial and foreign bodies

---

---

---

---

---

Cross out the incorrect words:

---

---

Cross out the incorrect word:

---

Which statements are true:

1. a + b + c
2. b + d + e
3. a + c + d
4. b + c + e
   b + c + e
5. c + d + e

1. The Epithelium can be separated from the corneal surface using a weak steroid solution.
2. The epithelium can be separated by the application of a weak alcohol solution.
   The epithelium can be separated by the application of a weak alcohol solution.
3. Epi - Lasik lifts the epithelium with a mechanical separator.
   Epi - Lasik lifts the epithelium with a mechanical separator.
4. Epi - Lasik results in a slightly slower visual recovery, but minimal post-operative pain.
5. Epi-Lasik results in rapid visual recovery compared to the alcohol separation method.
   Epi-Lasik results in rapid visual recovery compared to the alcohol separation method.

---

What is the correct thickness for each:

1. Superficial
   10 - 30microns wide; 0.2-10 microns thick
   20 - 40microns wide; 0.2-0.8 microns thick
   
   30 - 50microns wide; 0.2-1.2 microns thick
   30 - 50microns wide; 0.2-1.2 microns thick
2. Deep
   
   0 - 100microns wide; 0.5-1.5 microns thick
   0 - 100microns wide; 0.5-1.5 microns thick
   100 - 200microns wide; 1.0-2.5 microns thick
   250 - 350microns wide; 1.0-2 microns thick

---

Corneal structure consists of two types of corneal lamellae:

Cross out the incorrect word: