Ординатура / Офтальмология / Английские материалы / Oculoplasty and Reconstructive Surgery Made Easy_Garg,Touky, Nasralla_2009
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reluctant to buy it due it is high to cost. During that period one of my ENT surgeons visited my clinic and while discussing with him, he commented that for functioning any DCR surgery minimum 3 mm opening is required and this is not possible with laser DCR. Actually he was promoting endolaser DCR Then I contacted to endolaser surgeon and they said that repeated surgery is required and so they were also not happy.
A Thought
Now what to do? My mind was constantly wondering. During that period my son, who was studying in 3rd M.B.B.S. came to home. I was going through his new surgical book and that time I read a comment that “All drainage implant that comes in contact with air must be corrugated (e.g. Breast abscess) and all drainage implant that do not come in contact with air must be tubular (e.g. Hydrocephalous)”. With that statement I got the answer to the question, why intracystic implant was not working, because it was a tubular implant and was coming in contact in with air. With that thought in my mind I slept that night but I was unable to get sound sleep. Though, I stopped doing intracystic implant, in my mind there was something that can be done.
One Sunday evening I was sitting with my family. My mother in law came that morning to meet me. While talking with each other I suddenly got up and went down stare in my operation theater. I took small tube from saline set, made cut on both side and dipped in to the glass of water and to my surprise what I wanted had happened. Then I took intracystic implant and made similar cuts and I got the desired result. My idea worked and I got the solution to the problem. On the next patient I tried that idea and to my surprise it worked successfully. After that I tried this to so many patients and the results were fantastic.
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The idea is “To convert tubular drainage into corrugated drain”.
Then I presented a scientific paper at Maharashtra Ophthalmic Conference, Aurangbad for which I received the “Innovation Award”
Physics Principal (Figure 1)
The tubular implant when comes in contact with air function like a closed pipette. If the tip of the pipette is closed from above with the figure then the water column will not drain because, the atmospheric pressure is more than the pressure of water column in the tube. When the finger is removed the water column will drain out but a small drop of fluid at the bottom of will not drain. Even if you vigorously shake the tube that water will remain.
Figure 1: Closed and open pipettes
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Figure 2: Breast abscess and hydrocephalus
Have you seen a tubular drainage for breast abscess or rectal abscess? No.
Have you seen a corrugated drain for hydrocephalus? No
(Figure 2)
So the conclusion is:
Tubular intracystic implant behaves likes a closed pipette after the suturing of lacrimal sac. So water column remains in the tube but the drainage of fluid does not occur. To drain the fluid from the tube the implant must be corrugated
(Figure 3).
Theoretical Consideration
Functioning of Nasolacrimal Duct
The nasolacrimal tube is vertical tube. There is a valve at the lower end. The fluid forms a water column in to the nasolacrimal duct. With the inspiration fluid flow occurs because the intranasal atmospheric pressure goes below the pressure of water column in the nasolacrimal duct. With
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Figure 3: Tube function as closed pipette after sac suturing
Figure 4: Physiology of nasolacrimal duct
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expiration the intranasal atmospheric increases and the flow of fluid stops temporarily (Figure 4).
Functioning of DCR
In DCR, drainage works only when the intranasal atmospheric pressure is equal to the atmospheric pressure in to the lacrimal sac. Minimum 3 mm opening is sufficient for DCR to function
(Figure 5).
Drawbacks of Conventional Implant
A thought came in my mind that by simply inserting the tube in to the lacrimal sac and draining the fluid into the nasal
Figure 5: Drainage occurs when intranasal atmospheric pressure and sac pressure is balanced
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cavity though appears logically correct but technically it do not work. If the thing is so simple then why it is not so popular? There are few drawbacks of conventional implant.
•It is a tubular so it does not obey the law of physics and the basic surgical principle
•On table – patency is false positive because the fluid is forcibly injected in to the tube above the atmospheric pressure.
•Postoperative – Patency is false positive because the fluid is injected in to the tube above the atmospheric pressure.
•So in spite of positive result the patient’s complaints are persistent.
The aim is:
•To break the water column in to the tube.
•To break the surface tension of fluid into the tube.
The answer is:
To convert, the tubular drain in to corrugated drain
(Figure 6).
PREPARATION OF MODIFIED CORRUGATED IMPLANT
To convert intracystic in to “Modified corrugated implant” a cut is made on the tube from above (below the collar) and from the lower end. A strip of about 3 mm width is removed on either side of the wall of the tube exactly opposite to each other. The length of the strip is 2/3rd the length of the tube from above and from below overlapping in the center. Tip of the implant is closed by suturing with 6/0 silk (Figure 7).
Advantages of Dr Anil Shah’s Modified Corrugated Implant
•The vertical strip is removed from the tube breaks the water column and the surface tension of the fluid.
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Figure 6: Converting the tubular drain into corrugating drain
Figure 7: Anil Shah’s modified corrugated intracystic implant
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•Due to the removal of vertical strip, the tube is converted in to two corrugated plates.
•The vertical strip overlapping in the center forms a hole that gives air communication so that the atmospheric pressure in the nose and the sac is balanced. It also breaks the water column.
•If the tube is open at the end then, some time, the implant may not pass through nasal mucosa and tenting of nasal mucosa may occurs. But if the tip is closed with suture then it has many advantages. The implant can be fully loaded on the introducer. It can be easily introduced deep in to nasal cavity and the strength of the tube is also maintained.
Selection is
20 patients were operated in last 6 month between the age group of 30 to 70. Selected cases were of chronic dacryocystitis and mucocele. Failed DCR cases were excluded. All patients had sac patent postoperatively15 patient, who came follow up over 6 month had patent sac.
Surgical Procedure
In this technique intracystic implant developed by Dr. M.D. Pawar has been used. The intracystic implant has been used as a method of treatment for epiphora due to the obstruction to the nasolacrimal duct. The aim behind this design is to make surgical procedure safer, quicker and improve the success rate.
The conventional implant is technically easier. Bleeding during surgery is reduced and no nasal packing is required. The surgery becomes OPD procedure.
I have tried conventional implant but my success rate was low. So I made few modifications on the implant and made a
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new “Modified Corrugated Intracystic Implant” and my success rate improved significantly.
Available
The implant is available in ETO sterilized blister peel open pack, ready to use on table. Implant is prepared as per design. The implant can also be re sterilized by autoclaving.
Material
Modified corrugated implant (Figure 8). Introducer (Figure 9), Perforator (Figure 10), 5-0 Vicryl suture, and other surgical instrument for DCR.
Procedure
All the surgical procedures were done under local anesthesia similar to as used in conventional DCR. Sac is exposed. Identify medial palpebral ligament and exactly below make a vertical incision of about 3 mm on the anterior-lateral wall of the lacrimal sac.
Irrigate the sac with saline to remove blood and purulent material. Irrigate sac with 1;1000 adrenaline so as to avoid oozing during surgery (Figure 11).
Stay suture to implant: A suture is passed from lower end medial edge of vertical incision. It is passed from outside to inside in to the lumen of sac. The needle is taken out of the lumen and passed through the two holes of the intracystic implant below the collar of implant. Again the suture is passed inside to out side the medial wall of the lacrimal sac from the upper end of the vertical incision. Cut the needle from the suture. This is a “U” shaped loop of suture holding the implant to the lacrimal sac. After introducing the implant in to the nasal cavity the thread of the suture is pulled out and a
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Figure 8: Dr Anil Shah modified corrgated intracystic implant
Figure 9: Introducer for implant
Figure 10: Perforator for fracturing lacrimal bone