ACTA OPHTHALMOLOGICA VOL. 4 6 1968

From the University Eye Hospital, Oulu, Finland Head: Prof . H. Forsius

ROUTINE USE OF T H E OPERATING MICROSCOPE IN OCULAR SURGERY

BY

U . Krause and H. Forsius

The first ophthalmologist to adopt the use of the operating microscope seems to have been Perrit, in 1948, but others have been slow in following his example. Later an increasing number of authors have emphasized the advantages of microsurgery, e. g. Littman 1954, Dannheim 1961, Troutman and DeVoe 1964, Rizzuti 1964, Harms and Mackensen 1966, Roper-Hall 1967 a, b, Draeger 1967, Barraquer, Barraquer and Littmann 1967. Probably almost all big eye clinics possess operating microscopes, but in many places these seem to be only oc- casionally used. The enthusiasm displayed in acquiring these aids has flagged more rapidly than technical skill in their use has increased, and the initial difficulties experienced have created a bias against the method as such.

The introduction of microscopy was certainly delayed by the crudeness of the surgical instruments and suturation material previously available. However, instruments have been produced especially for microsurgery (Pierse 1967, Smith 1967), and there has been a corresponding development of atraumatic sutura- tion material. Since the technical prerequisities of better achievements with the operating microscope have thus been provided, it may be anticipated that this aid will be more utilized.

The great advantage of microsurgery undobtedly lies in the fact that the surgeon is able to see clearly what he is doing. In addition, he can alter the magnification so as to correspond to special needs. The benefit derived is obvious, e. g. on suturation of the cornea at an operation for cataract, or on transplantation of the cornea.

However, in microsurgery there are also a variety of drawbacks to be taken into account. The operator’s visual field is very limited (Figs. 1, 2 and 3), and it is surrounded by a large blind area, which he can see only by looking from beside the microscope. The person assisting at the operation is in a difficult

Received May 13th 1968.

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Fig. 1. The visual field at magnification X 6. Sacle unit one millimeter.

Fig. 2. The visual field at magnification X 10.

position (Fig. 4), because the microscope prevents him from easily wiewing the hole operative field, and it is in the way of his hands.

The surgeon cannot take any instruments to the operative field without looking from beside the microscope, since the direction of gaze through the

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Fig. 3. The visual field at magnification X 16. Figs 1 , 2 and 3 are taken through the micro- scope. W e use magnification X 6 at preparation of conjunctival flaps and at the stage of extraction in operations for cataract. Magnification X 10 and X 16 are mainly

used at suturation and examination.

Fig. 4. W e use Zeiss Opton microscope model 1964. Operator and assistant in typical postures.

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oculars does not coincide with the operative field, because the microscope is of angled type. In the microscope used in our Clinic (Zeiss Opton), the change of magnification and focusation is manual, which is rather awkward. In the new Zeiss operating microscope the change of magnification and focusation is mechanical. The use of bifocals is inconvenient, without correction a pres- byope does not see the sutures outside of the microscopic field. In addition, we suggest the use of ocular apertures large enough (1 1 mm in diameter) to allow the continuous use even of bifocals during operation.

In our opinion the operating microscope should not be occasionally employed, because a surgeon who is not used to it is clumsier in his manipulations than he is with the ordinary binocular loupe. Only an operator who uses the operat- ing microscope routinely can derive full benefit from it. In our hospital it took us almost a year until a standardized technique had been developed. The period of training is thus very long. In any event, full advantage cannot be taken of the method until a larger number of operations have been performed. Even if the operator is an experienced surgeon, the procedures require more time, and in the case of middle-aged or elderly ophthalmologists the difficulties are enhanced by the fact that it is always an effort to change a routine.

The operating microscope has been used by us at all operations for cataract and glaucoma and at all corneal operations carried out during the last four years. The residents who get their surgical training are from the outset tought to use microsurgery. Beginners are always slow, and this applies in particular

Fig . 5 .

forceps made especially for microsurgery. Some ordinary instruments in microscopic field. Magnification X 10. Note colibri-

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to those beginning to practise microsurgery. On the other hand, since they see their mistakes magnified, as well, the risk of complications is relatively less with this technique. When their training is terminated these ophthalmologists are familiar with the new technique and use the microscope at almost all stages of an operation. Since the demands made on operators certainly will be greater in the future and it seems probable that improved operating microscopes and instruments will be available, it may be anticipated that microsurgery will soon be adopted as a routine method in ophthalmology as it has been in operations on the inner ear.

SUMMARY

The advantages and drawbacks of microsurgery are discussed. I t is emphasized that benefit is derived from this method only when the operator and his as- sistants uses it routinely. When only occasionally employed, the microscope is a hindrance rather than an asset.

We have only favourable experiences from routine use of microsurgery at all operations on the anterior parts of the eye. Residents who get their training in ocular surgery at our hospital use the microscope from the outset at all intraocular operations. We recommend other training hospitals to adopt the same habit.

REFERENCES

Barraquer, J . I . , Barraquer, J . & Littmann, H.: A new operating microscope for ocular

Dannheim, H.: Ein Beitrag zur Mikrochirurgie. Klin. Mbl. Augenheilk. 1961: 138:

Draeger, J.: In Discussion to D. Pierse. Trans. Ophthal. SOC. U . K . 1967: 87: 230-234. Harms, H . & Mackensen, G.: Augenoperationen unter dem Mikroskop. Thieme, Stutt-

Littmann, H.: Ein neues Operations-Mikroskop. Klin. Mbl. Augenheilk 1954: 124:

Perrit, R. A.: cit. by Harms, H. & Mackensen, G.: Augenoperationen unter dem Mikro-

Pierse, D.: Microsurgery instrumentation and surgical technique. Trans. Ophthal. SOC.

Rizzuti, A. B.: Advances in microsurgery. Highl. Ophthal. 1964: 7 : 153-160. Roper-Hall, M . J.: The development and application of microsurgery. Trans. Ophthal.

Roper-Hall, M. J.: Microsurgery in ophthalmology. Brit. J . Ophthal. 1967 b: 51:

Smith, R.: In Discussion to D. Pierse. Trans. Ophthal. SOC. U . K . 1967: 87: 227-229. Troutman, R. & DeVoe, A . G.: Microsurgery. Highl. Ophthal. 1964: 7 : 162-180,

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SOC. U . K. 1967 a: 87: 195-203.

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