Training of eye-hand coordination: one student is working, and the another one is holding the optic.
1.Task: red, green, and blue slips of the paper are grasped one-by-one and based on their colours are put in the Petri dishes. This is done first with right and then with left hands (for the left-handed students, in a reversed manner).
2.Task: needle insertion into the plastic case. We grasp the needle and the case with the instruments.Following this, the needle is inserted into the case. It will not be successful if the needle and the case are not parallel to each other.
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10. Practice
Laparoscopic training in trainer box
Task: based on numbers and first with your right hand, put the rubber bands on the sticks located at the left side. Then, put these bands back to their orginal place with your left hand. The students are holding the optic by themselves. The duration of this activity is measured. A skilled student can perform this task in less than 2 minutes.
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9. Practice
Microsurgery: basic instrumentation and adjustement of microscope, microsurgical stich insertion
Aim of the parctice: to learn and practice the appropriate usage of basic microsurgical instruments, the suture-tying under magnification with a help of silicone rubber practice pad.
1.Appropriate handling of microsurgical instruments: to hold the following instruments as a pen. Instruments: curved-tipped forceps, jeweler (Adson) forceps, microsurgical scissors, microsurgical needle holder, strait dissector with locking system, vessel clip, microsurgical clip applicator, approximator
2.Loupe is a glasses like magnifying instrument. The eyepieces of loupe are adjustable to the surgeon’s pupil diameter, but the magnification is fixed. Put ont he instrument and adjust to our own pupil diameter, than fix the position.
3.Training in a laboratory with an operating microscope often takes long hours of concentrated work. This task is impossible to accomplish unless the surgeon has a comfortable and perfectly balanced position.
One should remove every object from the way of the legs on the ground which can disturb convenience. It is also important to have enough place for the knees, hence sitting at a table with drawers is not always suitable.
It determines two very important issues. On one hand, it affects the ability of manipulation, on the other hand it affects how we see through the microscope. We can only work without hand tremor if both forearms are resting on the table. One should not achieve this immobility by leaning on the elbows, as it quickly leads to fatigue and tremor of the hands. Turn the light source on, focus on the filed and instruments held in both hands into the middle of the field trying different magnifications. The final adjustment is provided by the conformity of body position and microscope adjustments. After a few occasions, we just briefly and routinely perform these procedures.
4.Swith on the microscope. Position the eyepieces at 0 diopter. Adjust the fine focus. Set the interpupillary distance. Choose the lowest magnification and focus on the spot that you previously marked by using the coarse focus. Choose the highest magnification and adjust the fine focus also for this magnification. The reason for starting the fine focusing at the highest magnification is that the microscope will be focused in the smallest depth of the field, thus allowing a perfect focus at all magnifications. Switch to the lowest magnification without modifying the focus, and set the eyepieces to the lowest possible diopter. Adjust the diopters separately for each eye by rotating the lens of the eyepiece clockwise.
5.It is particularly important to practice the stitching and knotting in microsurgery. We use 10/0-7/0 atraumatic needles which are permanently attached to a fine monofilament thread. The cross section of the needle is somewhat flat so it cannot turn around along its axis when held in the needle holder. We grab the needle closed to the thread (at 1/3 of the needle). At the beginning even grabbing of the needle represents a problem.
The recommended technique is shown here. Holding the thread in the left hand, lay the greater curvature of needle on the surface a way it gets into position where it is suitable to grab it with and instrument held in the right hand.
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For a right-handed person the steps are as follows: the needle is held in the forceps in the right hand, the forceps in the left hand is put under the incision (to expose the wound on the right side). Never grab the edge of the structure to be sutured with the forceps. The axis of the needle should be held perpendicularly to the surface to be sutured. The distance from the edge should be approx. two times the diameter of the needle.
On the left side: Let us make the tip of the needle get out exactly in line with the stitch on the right side. When the tip of the needle is visible on the left side, we grab it with the left forceps and pull the needle out. Be careful and do not disconnect the thread from the needle. Let us try to avoid surface friction by retracting with the left forceps when the needle is pulled through the rubber. When we pull the thread through counteract the friction by retracting with a forcep held int he right hand.
6. Microsurgical knotting evolves the simultaneous use of two instruments, similarly to the laparoscopic approach. In the clinical practice, two major methods of tying knots are applied: the one-handed and the two-handed versions. The one-handed version resembles the method used in macroscopic instrument-aided knotting procedures, because the long part of the thread is held always in the same hand, whereby the thread is passed into the other hand during the two-handed procedure.
Grab the long thread with the right needle holder at a distance which can be easily looped around the tip of the left forceps (direction: towards the “short end”, distance: 3 times the length of the “short end”. Reach and pull the “short end” through the loop with the left forceps (meanwhile do not let the loop slip off). Pull only the “long end” while firmly holding the “short end”, and tighten the knot.
When the knot is tightened, the edges of the rubber should only touch each other - do not overlap! In order to achieve this, the distance of the stitch from the edge should not be large and the knot must not be very much tightened. Do not pull the “short end”, pull only the “long end” otherwise the knot looses its ideal structure.
Move the”long thread” to the side of the short end, grab the “long end” now with the left hand (distance: 3 times the length of the “sort end”) and wrap it around the right forceps (direction: opposite to the “short end”) than grab the “short end” with the right forceps and pull it through the loop, and tighten the knot. Eventually, cut both the “short and long” ends approx. 3 mm long.
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10. Practice
Microsurgery: insertion stiches
The matter of the previous lesson is repeated during this section.
1.Taking on the appropriate body and hand position. Adjustment of the microscope or loupe.
2.Practice of the grabbing and adjustment of the needle–thread complex under magnification.
3.Making a 2 cm long incision on the rubber pad.
4.Insertion of interrupted microsurgical stiches. The distance between stiches are 0,5-1 mm.
5.Knotting under magnification.
6.A repeat the above mentioned excersises 5 or 10 times on the incisions lay in different directions.
The trainee should be able to tie 6 knots in 10 minutes to consider himself proficient in this excersise.
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