- Email: [email protected]
Continuous Circular Capsulorhexis (CCC)
SURGICAL TECHNIQUE
Continuous Circular Capsulorhexis {CCC) KIMIYA SHIMIZU Musashino Red Cross Hospital, Tokyo, Japan
INTRODUCTION
The requirements for ideal anterior capsulotomy are: (1) Symmetry; (2) No tears of the capsule edge; (3) Causing minimum stress to the ocular tissues. The role of the anterior capsule is very important in fixation of PCLs firmly in the capsular bag. In these days a can-opener capsulotomy is the most popular technique, and by this technique partial symmetry of the capsulotomy can be obtained, but damage to the zonule is not negligible. On the other hand the envelope technique causes little damage to the zonule but the shape of the capsulotomy is asymmetric, which may result in lens dislocation. By either method, radial tears of the anterior capsular edge occur leading to asymmetric fixation. So, we considered the new capsulotomy methods which satisfy the requirements for ideal capsulotomy stated above. As a result, new capsulotomy techniques were developed and recently introduced. These were named as 'Continuous Tear Capsulotomy' by Gimbel in 1984, 'Circular Capsulorhexis' by Neuhan in 1986, and 'Circular Capsulotomy' by myself in 1987. And at the AAO precongress in October 1988, it was decided to refine the three items as 'Continuous Circular Capsulorhexis' at Gimbel's suggestion. METHOD
Key points of this technique are: (1) focussing of microscope; (2) water tightness; (3) triangular flap; (4) rolling over the flap; (5) prevention of V -shaped tears. (1) Adjust the microscope so that it is perpendicular to the iris plane (2) Make the cystotome Bend the 25 G needle to 30° about 1 mm from the tip. Don't bend the needle too much, or it becomes difficult to control the needle point and can cause capsu0955-3681/90/020115+03 $03.00/0 © 1990 Bailliere Tindall
lar damage. With the needle bent to 30°, perforate the anterior chamber and perform the anterior capsulotomy. It is also possible to control the side of the needle to make an incision without damaging the capsule (Fig. 1).
Fig. 1 25 G needle: Bend the needle to 30°about 1 mm away from the tip to make a incision needle
(3) Forceps us. needle Some surgeons perforate the anterior chamber with micro blades, inject Healon in the anterior chamber and then incise the capsule with forceps. But by this method, it is difficult to maintain a deep anterior chamber, as Healon only creates space and does not continuously apply the pressure so as to keep the anterior chamber deep enough during capsulotomy. So, to perform CCC with the forceps may be dangerous. Using a bent 25 G needle, to perforate the anterior chamber, water tightness can be obtained and hydraulic pressure is constantly applied. Therefore a deep anterior chamber can be maintained during CCC and capsulotomy can be performed more easily and safely. Furthermore, by continuously applying water pressure, anterior displacement of nucleus is prevented so that radial tears at the anterior capsular edge are avoided, whereas it is often caused when the forceps are used. Moreover CCC may be connected to the can-opener technique when the needle is used. Personally, I consider that fewer instruments should be used for intraocular manipulation. Eur J Implant Ref Surg, Vol2, June 1990
K. Shimizu
116
(4) Triangular flap After the needle has been inserted in the anterior chamber, anterior capsulotomy is performed. At first, a triangular flap is made to prevent any tears running to the equator at the starting point of the incision. Any stress on the zonnule during CCC is only generated at this initial point. Therefore, it should be performed close to the centre of the anterior capsule. When the needle is inserted at 11 o'clock, the flap should start at 4 not 5 o'clock and about 2 mm away from the anterior capsule centre. Then roll over the flap to control the direction of incision in the subsequent steps (Figs 2 and 3).
do, inject Healon in the anterior chamber. At first lean the needle point towards the left from 5 o'clock to 10 o'clock to avoid damage on the anterior capsule, and make the incision. Then lean the needle towards right to incise between 10 and 5 o'clock. During this step, keep the flap folded over to control the direction (Figs 4 and 5).
ilL.
····-
Figs 4 and 5 Rolling over the flap: continue to fold the flap over as the incision is made
(6) Prevention ofV-shaped tear To prevent a tear at the starting point, carry on the capsulotomy, more than 360°, until the incision line overlaps the starting point, otherwise a V -shape tear can be easily obtained. ADVANTAGES OF CCC
(1) complete in-the-bag fixation (Fig. 6):
Figs 2 and 3 Triangular flap: Roll the needle over, make a small flap between 4-5 o'clock ·
(5) Rolling over the flap Next, by using the side of the needle, the flap is folded over and the incision is continued. If it is difficult to
Fig. 6 After CCC, a no-hole PCL is transplanted. The PCL is firmly fixated in the bag Eur J Implant Ref Surg, Vol2, June 1990
Continuous Circular Capsulorhexis
117
(2) soft lens can be implanted in the bag (Fig. 7); (3) cortical aspiration is easily performed.
Fig. 7 After CCC, physical fixation of a silicone PCL is firmly obtained
Eur J Implant Ref Surg, Vol2, June 1990
As capsular integrity is maintained after CCC, it is possible to attain complete fixation of the PCL in the bag. This prevents asymmetrical capsular shrinkage or postoperative dislocation ofPCLs caused by asymmetric fixation of an 101. It also makes physical fixation of soft IOLs possible. Furthermore the anterior capsule edge doesn't plunge into the aspiration port, thereby facilitating 1-A. This technique is recommended in cases of traumatic cataract or with pseudoexfoliative cataract which are susceptible to the effects of a weak zonule.
Continuous Circular Capsulorhexis {CCC) KIMIYA SHIMIZU Musashino Red Cross Hospital, Tokyo, Japan
INTRODUCTION
The requirements for ideal anterior capsulotomy are: (1) Symmetry; (2) No tears of the capsule edge; (3) Causing minimum stress to the ocular tissues. The role of the anterior capsule is very important in fixation of PCLs firmly in the capsular bag. In these days a can-opener capsulotomy is the most popular technique, and by this technique partial symmetry of the capsulotomy can be obtained, but damage to the zonule is not negligible. On the other hand the envelope technique causes little damage to the zonule but the shape of the capsulotomy is asymmetric, which may result in lens dislocation. By either method, radial tears of the anterior capsular edge occur leading to asymmetric fixation. So, we considered the new capsulotomy methods which satisfy the requirements for ideal capsulotomy stated above. As a result, new capsulotomy techniques were developed and recently introduced. These were named as 'Continuous Tear Capsulotomy' by Gimbel in 1984, 'Circular Capsulorhexis' by Neuhan in 1986, and 'Circular Capsulotomy' by myself in 1987. And at the AAO precongress in October 1988, it was decided to refine the three items as 'Continuous Circular Capsulorhexis' at Gimbel's suggestion. METHOD
Key points of this technique are: (1) focussing of microscope; (2) water tightness; (3) triangular flap; (4) rolling over the flap; (5) prevention of V -shaped tears. (1) Adjust the microscope so that it is perpendicular to the iris plane (2) Make the cystotome Bend the 25 G needle to 30° about 1 mm from the tip. Don't bend the needle too much, or it becomes difficult to control the needle point and can cause capsu0955-3681/90/020115+03 $03.00/0 © 1990 Bailliere Tindall
lar damage. With the needle bent to 30°, perforate the anterior chamber and perform the anterior capsulotomy. It is also possible to control the side of the needle to make an incision without damaging the capsule (Fig. 1).
Fig. 1 25 G needle: Bend the needle to 30°about 1 mm away from the tip to make a incision needle
(3) Forceps us. needle Some surgeons perforate the anterior chamber with micro blades, inject Healon in the anterior chamber and then incise the capsule with forceps. But by this method, it is difficult to maintain a deep anterior chamber, as Healon only creates space and does not continuously apply the pressure so as to keep the anterior chamber deep enough during capsulotomy. So, to perform CCC with the forceps may be dangerous. Using a bent 25 G needle, to perforate the anterior chamber, water tightness can be obtained and hydraulic pressure is constantly applied. Therefore a deep anterior chamber can be maintained during CCC and capsulotomy can be performed more easily and safely. Furthermore, by continuously applying water pressure, anterior displacement of nucleus is prevented so that radial tears at the anterior capsular edge are avoided, whereas it is often caused when the forceps are used. Moreover CCC may be connected to the can-opener technique when the needle is used. Personally, I consider that fewer instruments should be used for intraocular manipulation. Eur J Implant Ref Surg, Vol2, June 1990
K. Shimizu
116
(4) Triangular flap After the needle has been inserted in the anterior chamber, anterior capsulotomy is performed. At first, a triangular flap is made to prevent any tears running to the equator at the starting point of the incision. Any stress on the zonnule during CCC is only generated at this initial point. Therefore, it should be performed close to the centre of the anterior capsule. When the needle is inserted at 11 o'clock, the flap should start at 4 not 5 o'clock and about 2 mm away from the anterior capsule centre. Then roll over the flap to control the direction of incision in the subsequent steps (Figs 2 and 3).
do, inject Healon in the anterior chamber. At first lean the needle point towards the left from 5 o'clock to 10 o'clock to avoid damage on the anterior capsule, and make the incision. Then lean the needle towards right to incise between 10 and 5 o'clock. During this step, keep the flap folded over to control the direction (Figs 4 and 5).
ilL.
····-
Figs 4 and 5 Rolling over the flap: continue to fold the flap over as the incision is made
(6) Prevention ofV-shaped tear To prevent a tear at the starting point, carry on the capsulotomy, more than 360°, until the incision line overlaps the starting point, otherwise a V -shape tear can be easily obtained. ADVANTAGES OF CCC
(1) complete in-the-bag fixation (Fig. 6):
Figs 2 and 3 Triangular flap: Roll the needle over, make a small flap between 4-5 o'clock ·
(5) Rolling over the flap Next, by using the side of the needle, the flap is folded over and the incision is continued. If it is difficult to
Fig. 6 After CCC, a no-hole PCL is transplanted. The PCL is firmly fixated in the bag Eur J Implant Ref Surg, Vol2, June 1990
Continuous Circular Capsulorhexis
117
(2) soft lens can be implanted in the bag (Fig. 7); (3) cortical aspiration is easily performed.
Fig. 7 After CCC, physical fixation of a silicone PCL is firmly obtained
Eur J Implant Ref Surg, Vol2, June 1990
As capsular integrity is maintained after CCC, it is possible to attain complete fixation of the PCL in the bag. This prevents asymmetrical capsular shrinkage or postoperative dislocation ofPCLs caused by asymmetric fixation of an 101. It also makes physical fixation of soft IOLs possible. Furthermore the anterior capsule edge doesn't plunge into the aspiration port, thereby facilitating 1-A. This technique is recommended in cases of traumatic cataract or with pseudoexfoliative cataract which are susceptible to the effects of a weak zonule.