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Case 34a
by Dr. Mahadhir Alhady, Dr.
Ngo Chek Tung &
Professor Chua Chung Nen
Congenital ptosis with poor levator
function is the most common type of ptosis seen in young children. The
surgical method of choice is to perform frontalis suspension using either
synthetic materials (for example prolene and mersilene mesh) or autologous
tissues (such as fascia lata and palmaris longus1). And the most
commonly used instrument to introduce these materials is the Wright needle.
However, we find the Wright needle requires the use of a bigger skin wound
and causes more trauma. The instrument that we commonly employ in our
department is the 18-gauge intravenous catheter2. It has several advantages:
-
smaller size means better cosmetic
result and less trauma,
-
it is cheap and disposable,
-
the tip is always sharp because it is
not re-used.
Figure 1.
Showing the difference in size between a Wright needle and a G18 gauge
catheter
needle.
Figure 2. A
big wound and more tissue manipulation with a Wright needle (right) than
with a G18
needle.
Surgical techniques
-
A Fox3 pentagon was used
with five stab incisions using no. 11 blade, two in the eyelid, two in
the superior eyebrow margin, and one in the forehead.
-
The 18-gauge intravenous catheter
needle was inserted through the incision sites.
-
A lid guard was placed between the
globe and the eyelid to avoid accidental penetration of the eye by the
needle.
-
The 2/0 prolene was introduced through
the needle lumen to be placed deep to the orbicularis and
frontalis muscles (Figures below).
-
The sutures were lifted and tied at the
forehead incision to achieve the satisfactory lid height and contour.
Only the forehead incision needs suturing with 6.0 Vicryl to prevent
protrusion of the suture ends.
We have used this technique in 15 patients
(22 eyelids) with good cosmetic results.
Figure 3. Refer to surgical techniques for
explanation. Only the upper most forehead scar
needs suturing (K and L).
a. What is the
disadvantage of this technique?
There are two main
disadvantages with this technique:
i. The lumen of the
needle is small and therefore can not be used for the introduction of
larger materials such as fascia lata or mersilene mesh.
ii. The needle is
straight and may be difficult to used in adult who has a prominent
forehead. However, we have found that it is possible to get around the
problem by bending the needle with a artery forcep.
b. What
alternative instrument may be used?
Previous writers4 had proposed
the use of epidural needle in place of Wright needle. However,
we find the epidural needle has several disadvantages:
1. it is long and very flexible making creation of a straight
track difficult and
2. it is many times the cost of an
intravenous catheter needle.
Figure 4.
A patient with blepharoptosis before and after (5 days postoperative)
combine ptosis using
the above
technique and medial canthoplasty.
Figure 5. Two other patients before and after ptosis operation using G18
needle. The patient above also had an esotropia as a result of
deprivation amblyopia but unilateral suspension was sufficient to leave
the lid. Both patients have minimal forehead scars.
References:
1.Wong CY,
Fan DS, Ng JS, Goh TY, Lam DS. Long-term results of autogenous palmaris
longus frontalis sling in children with congenital ptosis. Eye. 2005
May;19(5):546-8.
2. Alhady M, Ngo CT, Tan AK, Chua CN. Use of 18-gauge intravenous catheter
needle for frontalis suspension in children with congenital ptosis. Eye.
2006 Oct 13; [Epub ahead of print]
3. Fox SA.
Ophthalmic Plastic Surgery, 3rd edn. Grune & Stratton: New York, NY, 1963.
4. Davi G, Modorati G, Brancato R. A disposable needle for frontalis
suspension surgery in congenital ptosis. Ophthalmic Surg Lasers 1997; 28(7):
607–608.
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