EYEBALL
Anteroposterior stability of eyeball is provided by all except:
| A |
Suspensory ligament of the eye ball |
|
| B |
Superior oblique |
|
| C |
Superior rectus |
|
| D |
Orbital fat |
Anteroposterior stability of eyeball is provided by all except:
| A |
Suspensory ligament of the eye ball |
|
| B |
Superior oblique |
|
| C |
Superior rectus |
|
| D |
Orbital fat |
Suspensory ligament of the eye ball [Ref. Gray’s Anatomy 40/e p658; Last’s anatomy: regional and applied By Chummy S. Sinnatamby, Raymond Jack Last 11/e p417; Clinical anatomy of the eye By Richard S. Snell, Michael A. Lemp p133]
- The suspensory ligament (of Lockwood) is a part of fascial sheath encasing the eye ball. It forms a hammock stretching below the eyeball between the medial and lateral check ligaments and enclosing the inferior rectus and inferior oblique muscles of the eye.
- The ligament supports the eye, and prevents downward displacement of it.
- Gray’s 40/e p658 writes- “A continuous fascial band, the suspensory ligament of the eye, is slung like a hammock below the eye, providing sufficient support such that, even when the maxilla (forming the floor of the orbit) is removed, the eye will retain its position.”
| A |
25 mm |
|
| B |
24 mm |
|
| C |
23.5 mm |
|
| D |
23 mm |
Ans. 24 mm
Smallest diameter of the eyeball is:
| A |
Vertical |
|
| B |
Horizontal |
|
| C |
Anteroposterior |
|
| D |
More than 24 mm |
Ans. Vertical
“The dimensions of the eye are reasonably constant, varying among individuals by only a millimetre or two; the sagittal (vertical) diameter is about 24 millimetres (about one inch) and is usually less than the transverse diameter.” Magill’s Medical Guide Revised Edition; Brain.
Circumference of an adult eyeball is:
| A |
80 mm |
|
| B |
65 mm |
|
| C |
75 mm |
|
| D |
70 mm |
Ans. 75 mm
Volume of an adult eyeball is:
| A |
7.5 mL |
|
| B |
6.5 mL |
|
| C |
5.5 mL |
|
| D |
8 mL |
Ans. 6.5 mL
Weight of an adult eyeball is:
| A |
7 g |
|
| B |
9 g |
|
| C |
11 g |
|
| D |
13 g |
Ans. 7 g
Anterior segment of the eyeball includes structures lying in front of the:
| A |
Iris |
|
| B |
Crystalline lens |
|
| C |
Vitreous body |
|
| D |
Cornea |
Ans. Cornea
Posterior segment of the eyeball includes structures present posterior to the:
| A |
Posterior surface of the lens and zonules |
|
| B |
Iris and pupilVitreous body |
|
| C |
Anterior surface of the lens and zonules |
|
| D |
None |
Ans. Posterior surface of the lens and zonules
If the length of eyeball increases by 1 mm. The net effect will be:
September 2007
| A |
Myopia of 6D |
|
| B |
Hypermetropia of 6D |
|
| C |
Myopia of 3D |
|
| D |
Hypermetropia of 3D |
Ans. C: Myopia of 3D
