|Year : 1984 | Volume
| Issue : 4 | Page : 225-228
Microsurgical techniques of levator resection
SM Betharia, Y Dayal
Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
S M Betharia
R.P. Centre for Ophthalmic Sciences, AI1MS, New Delhi-110 029
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Betharia S M, Dayal Y. Microsurgical techniques of levator resection. Indian J Ophthalmol 1984;32:225-8
The levator resection is the method of choice in the management of congenital ptosis as an initial procedure because it is the most physiological way to resect and strengthen the muscle and also the procedure causes minimum lagophthalmos as against the sling operations. The clarity of dissection and proper identification of the various structures under microscope cause minimum reaction and adequate correction. The aim of this paper is to highlight the important aspects of levator surgery and emphasize the advantages of microsurgery in levator resection.
| Material and methods|| |
The levator surgery was carried out both by the skin as well as by the conjunctival approach in 35 eyes. The cases included in this study included different varieties like congential, post traumatic, acquired and ptosis associated with blepharophimosis.
The residual ptosis, post traumatic ptosis and the ptosis with blepharophimosis, were tackled through the skin approach whereas in congenital ptosis both transcutaneous and transconjunctival routes were carried out. The results were compared with similar group of cases operated without using any magnification.
Important surgical steps: Transcutaneous approach:_
After marking with gentian violet the incision was made at the proposed site of lid fold. The skin and orbicularis flap was reflected and the levator identified. The orbital septum was identified and the pad of fat was herniated. Subconjunctival injection of 2% xylocaine was given to facilitate the separation of conjunctiva and Muller's muscle from the levator. The levator attachment at the tarsal plate was cut and after cutting the horns the levator was made free. Measured amount of excision was done after passing 3 double armed sutures through the tarsal plate and the levator: An advancement of 2 mmwas also done. The countour of the lid margin was assessed before tieing the knots of catgut sutures finally. The lid fold was then formed and the modified Frost suture given.
The lid was everted on Dessemarre's lid retractor. Incision in the conjunctiva was made after infiltrating it with 2% xylocaine. The conjunctival flap was reflected. Another injection of 2% xylocaine was given from the skin side to separate the skin and orbicularis from the levator. The levator was cut at its attachment with the tarsal plate. The lid retractor was then placed between the levator and the skin & orbicularis lamina of the lid.
The orbital septum was incised to prolapse the pad of fat. The horns were cut to make the levator free. Thin part of the upper border of tarsal plate was excised to make its surface raw for adhesion of levator to tarsal plate. 3 double armed 5-0 black silk sutures were passed through the conjunctival edge were then passed through the levator and through the tarsal plate and were brought out at the proposed site of lid fold to form the lid fold. The contour of lid margin was assessed. The levator was excised. The modified Frost suture was given.
Surgical results : Excellent results were obtained by using microscope. Details are given in [Table - 1][Table - 2].
| Discussion|| |
The result of levator resection depends upon the amount of resection as well as the proper dissection of the muscle. the initial incision at the proposed site of the lid fold is through the skin and orbicularis muscle. The levator apponeurosis is seen under microscope as a shining sheet with vertical fibres whereas the orbicularis has horizontal fibres. The orbital septum can be clearly defined under magnification and the orbital pad of fat is herniated out [Figure - 1] A. This is an important step which further helps in proper identification of levator. The superior transverse ligament is then identified which is at the junction of the tendinous and the muscular part of the levator [Figure - 1]B. The lateral horn of the levator which divides the lacrimal gland into palpebral and orbital part can be clearly defined and so also the relationship of the reflected part of superior oblique tendon to the medial horn [Figure - 2]A,B. Thus the damage to lacrimal gland and ducts, causing bleeding and damage to superior oblique causing diplopia, is avoided. The marginal arcade is seen running horizontally just above the level of upper border of tarsal plate and similarly the peripheral arcade at the two cornears of the lid margin. The damage to the vascular arcades which causes bleeding is thus avoided. While dissecting the levatorfrom the conjunctiva and Muller's muscle complex the damage to the Muller's muscle and conjunctiva is easily avoided without causing buttonholing of the conjunctiva. Levator insertion into the conjunctival fornix, can be easily identified and its dissection, from the fornix, is carefully avoided preventing the prolapse of the conjunctiva. The branches of the superior divisionof 3rd nerve supplying the levator from the undersurface can be clearly identified. In cases of post-traumatic and residual ptosis, the fibrous strands can be identified and clearly defined before excision [Figure - 3]A, specially near the orbital septum to make the levator absolutely free before its excision and advancement [Figure - 3]B &[Figure - 4]. In case of acquired ptosis and senile ptosis the magnification aids in proper identification of the defects in the aponeurosis of the levator and its repair can be done under direct vision. The use of microscope facilitates the dissection specially in cases of blepharophimosis where the muscle is fibrous and thick and also in cases of plexiform neurofibromatosis where it is infiltrated with neurofibromatous tissue. In cases of neurofibromatosis. the tortuous vessels can be easily identified and cauterized to provent the bleeding. The formation of lid fold, which is of great cosmetic value, is definitely aided by using microscope. It is important to take thin bites from levator and sometimes tarsal plate, apart from the upper and lower edges of the skin and orbicularis (Figure 4],[Figure 5). Excision of orbital pad of the fat and taking bites from orbital septum should be avoided to form the lid fold, which remains dynamic and does not become a frozen one as it happens in the hands of the average ptosis surgeon.
| Summary|| |
The various steps of the levator surgery done under the microscope for different types of ptosis with the advantages achieved by the use of magnification are highlighted. The use of microscope is recommended specially for operating cases of residual ptosis, traumatic ptosis and complicated cases of ptosis associated with blepharophimosis syndrome and in cases of plexiform neurofibromatosis.
| References|| |
1982 Symposium on diseases and surgery of the lids, lacrimal apparatus and orbit, The C.V. Mosby Co. St. Louis, p. 86.
Fox, S.A. '1970'. Ophthalmic Plastic Surgery, 5th edi., p 366, Grune and Stratton.
E. Wolff, '1976', Anatomy of the eye and orbit, 6th ed., p. 185, H.K Lewis and Co. Ltd., London.
Crowell B '1981' 'Ptosis' 3rd ed., The C.V. Mosby Company, St. Louis. p. 211.
[Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4], [Figure - 5]
[Table - 1], [Table - 2]