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New Instrument Developed to Assist Splitting of the Nucleus in Cataract Surgery During Phacoemulsification
Short Reports
217
The most usual cause is the exit of a loop out of the bag. A pea-podding or capsular shrinkage appears to be a minor factor of intracapsular decentration. The haptic of the spiral lens has definite specificities. It is not a loop but an encircling blade, very rigid in the implant plane but not perpendicular to it. The technique of implantation [4] after envelope capsulotomy and planned ECCE guarantees a stable position of the haptic along the whole bag equator without any spring effect. Escape of the haptic out of the bag cannot occur. However a slight upward decentration may be seen in full dilatation in 20% of cases (Table 2). It is probably due to a pea-podding effect, exerted by the lower bag upon the whole implant and not counteracted by the upper floppy part of the bag. Capsulorhexis without rim tears ensures on the contrary a symmetrical capsular bag. Escape of the rigid encircling haptic out of the bag is impossible. Furthermore, no asymmetrical pea-podding effect can occur. Rhexis and phacoemulsification decrease dramatically the incidence of spiral IOL decentration. This goal is essential if multifocal or small and oval optics are to be successfully used.
New Instrument Developed to Assist Splitting of the Nucleus in Cataract Surgery During Phacoemulsification PIETRO LISCHETTI UniversityEyeC/inicofRome 'TorVergata', C./. Columbus, Via della Pineta Sacchetti 506, Rome, Italy
OBJECTIVE: To show the workings of a new instrument designed to split the lens along the cross-shaped grooves during phacoemulsification. SETTING: University Eye Clinic of Rome 'Tor Vergata', C.I. Columbus, Via della Pineta Sacchetti 506 Rome, Italy. PATIENTS: Those in need of cataract surgery. RESULTS: The new forceps operates by exerting pressure on the wall of the nucleus grooves previously performed with the tip of the phacoemulsifier. CONCLUSIONS: The instrument provides an additional and safer step in avoiding the risks of using ultrasound near to the posterior lens capsule. Keywords: Cataract; Phacoemulsification; Forceps; Nucleus; Splitting
CONCLUSIONS
Capsulorhexis and phacoemulsification guarantee a better postoperative centration of Spiral IOL than the envelope technique does. Reduction of the diameter of the optics is therefore possible without losing safety. In this series the percentage of CME is lower after phaco than after planned ECCE but additional data are needed to demonstrate this statistically.
REFERENCES 1 A Galand and M Delmelle. Preliminary reort on the rigid disc lens. J. Cataract Refract. Surg., 1986; 12' 394-397. 2 HV Gimbel. Capsulotomy method eases in-the-bag PCL. Ocular Surgery News, 1985; 1: 20. 3 T Neuhann. Theorie und Operationstechnik der Kapsulorhexis. Klin. Mbl. Augenheilk., 1987; 190: 542-545. 4 G Meur. Small incision disc lens. Eur. J. Implant Ref Surg., 1989; 1: 64-66. 5 G Meur, M Maenhaut. Un implant disque rigide pour petites incisions. Bull. Soc. Belge Ophthalmol., 1988; 229: 81-85. 6 G Meur. Cataract Surgery: New Techniques-Part I (letter). Highlights ofOphthalmology, 1992; 20:4-7. 7 A Gaskell and PS Baines. Comparison of flexible loop posterior chamber lens implant centration following intercapsular versus extracapsular cataract surgery. Implant and Refractive Surgery, 1988; 6: 3-4, 88-91. 8 SO Hansen, MR Tetz, KD Solomon, MD Borup, RN Brems, DJC O'Morchoe, 0 Bouhaddou, DJ Apple. Decentration of flexible loop posterior chamber intraocular lenses in a series of 222 postmortem eyes. Ophthalmology, 1988; 95: 344-349. Eur J Implant Ref Surg, Vol 5, September 1993
INTRODUCTION
Phacoemulsification has become one of the most popular procedures in the surgical treatment of cataract. According to· Gimbel ('divide and conquer') and Sheperd's modification, the technique consists of sculpturing the nucleus of the lens with the tip of the phacoemulsifier into two cross-shaped grooves of 90-95% in depth and then fracturing in four parts [1]. This technique permits a simple emulsification of the lens material by offering two major advantages: (1) it allows the surgeon to perform phacoemulsification of any type of cataract and in eyes with mild mydriasis; (2) it allows the surgeon to perform phacoemulsification further away from the cornea thus preventing any contact with the corneal endothelium. This technique requires experienced surgeons [2], since the cutting of deep and definite grooves is the first important step in splitting the lens nucleus into Correspondence to: Pietro Lischetti, Via A. Torlonia 12, 00161, Rome, Italy. The author has no financial interest in the instrument presented in the paper.
218
Short Reports
Fig.1
four parts. The purpose of this paper is to present a new instrument which provides surgeons with a safer and easier procedure for splitting the nucleus during phacoemulsification.
MATERIAL AND METHODS
The instrument consists of a very thin pair offorceps 11 em long, the terminal parts of which are 1 em long and slightly arched (Fig. 1). The tips are valveshaped and closely clamped together when in the rest position. On opening, by a simple pressing of the handle, the terminal parts diverge (5-6mm), their base unmodified (2 mm), in the manner of a compass. Following capsulorhexis, hydrodissection with balanced salt solution (BSS) is performed. Two cross-~haped grooves, less deep than the standard procedures, are made along the 12 to 6 and 3 to 9 o'clock meridian. A gentle pressure superiorly applied to the handle will apply force in the opposite direction on the tip of the instrument, thus facilitating the splitting of the nucleus. The above procedure is then repeated by rotating the nucleus to the other three meridians.
CONCLUSION
emulsification during extracapsular cataract surgery. However, to succeed in a complete splitting of the nucleus, the tip of the phacoemulsifier should penetrate 90-95% into the nucleus itself. This procedure requires experienced surgeons, as damage to the posterior lens capsule could occur. The present forceps provides a safer and easier step when splitting the nucleus without the risk of getting too close with the tip of the phacoemulsifier to the posterior lens capsule. While other methods have been proposed for splitting the nucleus without the phacoemulsifier [3, 4], our instrument can be introduced into wounds of 3 mm width or less, with the advantage of having a major opening capacity of its terminal parts. REFERENCES 1 JR Sheperd. In situ fracture. J. Cataract Refract. Surg., 1990; 16: 436-440. 2 OA Cruz, GW Wallace, CA Gay, AY Matoba, DD Koch. Visual results and complications of phacoemulsification with intraocular lens implantation performed by ophthalmology residents. Ophthalmology, 1992; 99: 448-452. 3 JH Levy, AM Pisacano, RD Anello. A new endocapsular nucleus controller to facilitate nuclear splitting during bimanual endocapsular phacoemulsification. Eur. J. Implant Ref Surg., 1992; 4: 121-122. 4 SF Brint, JE Blaydes, L Bloomberg, P Crozafon, HI Fine, MC Kraff, J Filippelli, J Hoffman. Initial experience with the hydrosonic instrument to soften cataracts before phacoemulsification. J. Cataract Refract. Surg., 1992; 18: 130-134.
Since its introduction in 1988, Sheperd's technique has been widely accepted and used for lens phacoEur J Implant Ref Surg, Vol5, September 1993
217
The most usual cause is the exit of a loop out of the bag. A pea-podding or capsular shrinkage appears to be a minor factor of intracapsular decentration. The haptic of the spiral lens has definite specificities. It is not a loop but an encircling blade, very rigid in the implant plane but not perpendicular to it. The technique of implantation [4] after envelope capsulotomy and planned ECCE guarantees a stable position of the haptic along the whole bag equator without any spring effect. Escape of the haptic out of the bag cannot occur. However a slight upward decentration may be seen in full dilatation in 20% of cases (Table 2). It is probably due to a pea-podding effect, exerted by the lower bag upon the whole implant and not counteracted by the upper floppy part of the bag. Capsulorhexis without rim tears ensures on the contrary a symmetrical capsular bag. Escape of the rigid encircling haptic out of the bag is impossible. Furthermore, no asymmetrical pea-podding effect can occur. Rhexis and phacoemulsification decrease dramatically the incidence of spiral IOL decentration. This goal is essential if multifocal or small and oval optics are to be successfully used.
New Instrument Developed to Assist Splitting of the Nucleus in Cataract Surgery During Phacoemulsification PIETRO LISCHETTI UniversityEyeC/inicofRome 'TorVergata', C./. Columbus, Via della Pineta Sacchetti 506, Rome, Italy
OBJECTIVE: To show the workings of a new instrument designed to split the lens along the cross-shaped grooves during phacoemulsification. SETTING: University Eye Clinic of Rome 'Tor Vergata', C.I. Columbus, Via della Pineta Sacchetti 506 Rome, Italy. PATIENTS: Those in need of cataract surgery. RESULTS: The new forceps operates by exerting pressure on the wall of the nucleus grooves previously performed with the tip of the phacoemulsifier. CONCLUSIONS: The instrument provides an additional and safer step in avoiding the risks of using ultrasound near to the posterior lens capsule. Keywords: Cataract; Phacoemulsification; Forceps; Nucleus; Splitting
CONCLUSIONS
Capsulorhexis and phacoemulsification guarantee a better postoperative centration of Spiral IOL than the envelope technique does. Reduction of the diameter of the optics is therefore possible without losing safety. In this series the percentage of CME is lower after phaco than after planned ECCE but additional data are needed to demonstrate this statistically.
REFERENCES 1 A Galand and M Delmelle. Preliminary reort on the rigid disc lens. J. Cataract Refract. Surg., 1986; 12' 394-397. 2 HV Gimbel. Capsulotomy method eases in-the-bag PCL. Ocular Surgery News, 1985; 1: 20. 3 T Neuhann. Theorie und Operationstechnik der Kapsulorhexis. Klin. Mbl. Augenheilk., 1987; 190: 542-545. 4 G Meur. Small incision disc lens. Eur. J. Implant Ref Surg., 1989; 1: 64-66. 5 G Meur, M Maenhaut. Un implant disque rigide pour petites incisions. Bull. Soc. Belge Ophthalmol., 1988; 229: 81-85. 6 G Meur. Cataract Surgery: New Techniques-Part I (letter). Highlights ofOphthalmology, 1992; 20:4-7. 7 A Gaskell and PS Baines. Comparison of flexible loop posterior chamber lens implant centration following intercapsular versus extracapsular cataract surgery. Implant and Refractive Surgery, 1988; 6: 3-4, 88-91. 8 SO Hansen, MR Tetz, KD Solomon, MD Borup, RN Brems, DJC O'Morchoe, 0 Bouhaddou, DJ Apple. Decentration of flexible loop posterior chamber intraocular lenses in a series of 222 postmortem eyes. Ophthalmology, 1988; 95: 344-349. Eur J Implant Ref Surg, Vol 5, September 1993
INTRODUCTION
Phacoemulsification has become one of the most popular procedures in the surgical treatment of cataract. According to· Gimbel ('divide and conquer') and Sheperd's modification, the technique consists of sculpturing the nucleus of the lens with the tip of the phacoemulsifier into two cross-shaped grooves of 90-95% in depth and then fracturing in four parts [1]. This technique permits a simple emulsification of the lens material by offering two major advantages: (1) it allows the surgeon to perform phacoemulsification of any type of cataract and in eyes with mild mydriasis; (2) it allows the surgeon to perform phacoemulsification further away from the cornea thus preventing any contact with the corneal endothelium. This technique requires experienced surgeons [2], since the cutting of deep and definite grooves is the first important step in splitting the lens nucleus into Correspondence to: Pietro Lischetti, Via A. Torlonia 12, 00161, Rome, Italy. The author has no financial interest in the instrument presented in the paper.
218
Short Reports
Fig.1
four parts. The purpose of this paper is to present a new instrument which provides surgeons with a safer and easier procedure for splitting the nucleus during phacoemulsification.
MATERIAL AND METHODS
The instrument consists of a very thin pair offorceps 11 em long, the terminal parts of which are 1 em long and slightly arched (Fig. 1). The tips are valveshaped and closely clamped together when in the rest position. On opening, by a simple pressing of the handle, the terminal parts diverge (5-6mm), their base unmodified (2 mm), in the manner of a compass. Following capsulorhexis, hydrodissection with balanced salt solution (BSS) is performed. Two cross-~haped grooves, less deep than the standard procedures, are made along the 12 to 6 and 3 to 9 o'clock meridian. A gentle pressure superiorly applied to the handle will apply force in the opposite direction on the tip of the instrument, thus facilitating the splitting of the nucleus. The above procedure is then repeated by rotating the nucleus to the other three meridians.
CONCLUSION
emulsification during extracapsular cataract surgery. However, to succeed in a complete splitting of the nucleus, the tip of the phacoemulsifier should penetrate 90-95% into the nucleus itself. This procedure requires experienced surgeons, as damage to the posterior lens capsule could occur. The present forceps provides a safer and easier step when splitting the nucleus without the risk of getting too close with the tip of the phacoemulsifier to the posterior lens capsule. While other methods have been proposed for splitting the nucleus without the phacoemulsifier [3, 4], our instrument can be introduced into wounds of 3 mm width or less, with the advantage of having a major opening capacity of its terminal parts. REFERENCES 1 JR Sheperd. In situ fracture. J. Cataract Refract. Surg., 1990; 16: 436-440. 2 OA Cruz, GW Wallace, CA Gay, AY Matoba, DD Koch. Visual results and complications of phacoemulsification with intraocular lens implantation performed by ophthalmology residents. Ophthalmology, 1992; 99: 448-452. 3 JH Levy, AM Pisacano, RD Anello. A new endocapsular nucleus controller to facilitate nuclear splitting during bimanual endocapsular phacoemulsification. Eur. J. Implant Ref Surg., 1992; 4: 121-122. 4 SF Brint, JE Blaydes, L Bloomberg, P Crozafon, HI Fine, MC Kraff, J Filippelli, J Hoffman. Initial experience with the hydrosonic instrument to soften cataracts before phacoemulsification. J. Cataract Refract. Surg., 1992; 18: 130-134.
Since its introduction in 1988, Sheperd's technique has been widely accepted and used for lens phacoEur J Implant Ref Surg, Vol5, September 1993