Removal of Dislocated Lens Fragments During Cataract Surgery
Removal of Dislocated Lens Fragments During Cataract Surgery
Conventionally, nuclear fragments that fall onto the retina during phacoemulsification are removed by three-port PPV at a second surgery. To perform this second surgery, the surgeon must be experienced in vitreal surgery and must have vitreal instruments, for example, the body of instruments for vitreal surgery. If the second surgery is delayed, there is a higher incidence of complications, for example, corneal oedema, uveitis, glaucoma and retinal detachment. As a general rule, cataract surgeons who have experience with retinal surgery can remove dislocated nuclear fragments during cataract surgery if the appropriate vitreal instruments are available.
One advantage of our procedure is that it can be performed through the incision for cataract surgery during that surgery without the need for a three-port PPV later. In addition, the body of the instruments for vitreal surgery is not required. However, having only an anterior vitreous cutter and a fragmatome are not enough to remove dislocated nuclear fragments because the fragments on the retina cannot be seen without intraocular illumination. The tip of a 27-gauge Twinlight illuminator is long and narrow, and can be fixed to the anterior vitreous cutter and fragmatome. For our technique, we fixed the tip of a 27-gauge Twinlight illuminator near the tip of the anterior vitreous cutter and fragmatome so that the dislocated nuclear fragments on the retina could be seen. If the surgical field was still dark, two 27-gauge Twinlight illuminators were fixed to the anterior vitreous cutter and fragmatome.
Both Borne et al and Al-Khaier et al reported that the retinal detachment rate was higher in patients who had undergone phacofragmentation. This was probably due to an accidental aspiration of vitreous fibres by the fragmatome leading to a tractional retinal detachment. We moved the lens fragments to the anterior chamber where they can be divided and removed by grasping without emulsification. These procedures can then protect the retina from the ultrasonic vibrations and reduce the possibility of aspirating vitreous fibres. Making the vitreous body visible with triamcinolone acetonide allowed us to be sure that the core vitrectomy was complete. In addition, the visibility minimised the chances of aspirating peripheral vitreous fibrils by the fragmatome.
Aaberg et al reported that aggressive attempts to retrieve intravitreal lens fragments with a limbal-based approach during cataract surgery can lead to giant retinal tears. They used deep vitrectomy with abundant irrigation of the vitreous cavity. Vitreous cavity phacoemulsification was also attempted by anterior segment surgeons at the time of cataract surgery.
In our procedure, we did not use profuse irrigation of the vitreous cavity, and vitreous cavity phacoemulsification was not attempted. We carried out core vitrectomy with good visibility, thus the risk of vitreal traction on the retina was low.
Cases with dislocated nuclear fragments larger than one-fourth the size of the lens nucleus required cutting the peripheral vitreous fibrils. However, these peripheral vitreous fibrils were not easily incised, and the peripheral retina cannot be carefully examined for retinal tears in our procedure. The larger nuclear fragments were more likely to pull on peripheral anterior vitreous gel, thus increasing the risk of a retinal tear. So we excluded cases with nuclear fragments greater than one-fourth the size of the lens nucleus. We also excluded cases without a posterior vitreous detachment (PVD) because we believed that creating a PVD with a low cutting rate has a high risk of producing retinal tears and detachments, and so we performed the core vitrectomy without having to create a PVD.
The eye with a final BCVA of 0.4 had an ERM, and we believe it was the cause of the decreased BCVA. We excluded eyes with a history of retinal detachments because they were at a higher risk of retinal detachments, which our procedure cannot treat.
Because a good view is necessary, only cases with a sclerocorneal incision were suitable for this technique. For the core vitrectomy, the vitreous cutter must be inserted more vertically, which tended to create corneal folds that can reduce the intraoperative view of the surgical field. To overcome this, we expanded the inner part of the sclerocorneal incision from the usual 2.75 mm to approximately 4 mm or more in length; however, the outer part was 2.75 mm, which eliminated the need of profuse irrigation of the vitreous cavity during anterior and core vitrectomy. We also did not use our procedure in cases with a corneal incision because the Oshio wide-field lens would overlap it.
In our cases, the corneal endothelial cell loss (28.0±14.9%) was higher than that reported after PPV phacofragmentation. We believe that this was because the lens nuclei in our cases were harder than those during PPV phacofragmentation. Another possible reason was that there was more manipulation in the anterior chamber while suturing the intraocular lens to the ciliary sulcus in two eyes.
If an ophthalmological surgical illuminator is not available, then a strong light source, for example, operating microscope light fibre can be used.
In conclusion, we present a technique for removing dislocated lens fragments that are smaller than one-fourth the size of the lens nucleus through the sclerocorneal incision made for cataract surgery. This technique does not require a second surgery or the body of instruments for vitreal surgery. Our method may not be a safe alternative to PPV due to the small study number of six eyes. A larger number of cases is needed to assess its safety fully, in particular for retinal tears and detachments.
Discussion
Conventionally, nuclear fragments that fall onto the retina during phacoemulsification are removed by three-port PPV at a second surgery. To perform this second surgery, the surgeon must be experienced in vitreal surgery and must have vitreal instruments, for example, the body of instruments for vitreal surgery. If the second surgery is delayed, there is a higher incidence of complications, for example, corneal oedema, uveitis, glaucoma and retinal detachment. As a general rule, cataract surgeons who have experience with retinal surgery can remove dislocated nuclear fragments during cataract surgery if the appropriate vitreal instruments are available.
One advantage of our procedure is that it can be performed through the incision for cataract surgery during that surgery without the need for a three-port PPV later. In addition, the body of the instruments for vitreal surgery is not required. However, having only an anterior vitreous cutter and a fragmatome are not enough to remove dislocated nuclear fragments because the fragments on the retina cannot be seen without intraocular illumination. The tip of a 27-gauge Twinlight illuminator is long and narrow, and can be fixed to the anterior vitreous cutter and fragmatome. For our technique, we fixed the tip of a 27-gauge Twinlight illuminator near the tip of the anterior vitreous cutter and fragmatome so that the dislocated nuclear fragments on the retina could be seen. If the surgical field was still dark, two 27-gauge Twinlight illuminators were fixed to the anterior vitreous cutter and fragmatome.
Both Borne et al and Al-Khaier et al reported that the retinal detachment rate was higher in patients who had undergone phacofragmentation. This was probably due to an accidental aspiration of vitreous fibres by the fragmatome leading to a tractional retinal detachment. We moved the lens fragments to the anterior chamber where they can be divided and removed by grasping without emulsification. These procedures can then protect the retina from the ultrasonic vibrations and reduce the possibility of aspirating vitreous fibres. Making the vitreous body visible with triamcinolone acetonide allowed us to be sure that the core vitrectomy was complete. In addition, the visibility minimised the chances of aspirating peripheral vitreous fibrils by the fragmatome.
Aaberg et al reported that aggressive attempts to retrieve intravitreal lens fragments with a limbal-based approach during cataract surgery can lead to giant retinal tears. They used deep vitrectomy with abundant irrigation of the vitreous cavity. Vitreous cavity phacoemulsification was also attempted by anterior segment surgeons at the time of cataract surgery.
In our procedure, we did not use profuse irrigation of the vitreous cavity, and vitreous cavity phacoemulsification was not attempted. We carried out core vitrectomy with good visibility, thus the risk of vitreal traction on the retina was low.
Cases with dislocated nuclear fragments larger than one-fourth the size of the lens nucleus required cutting the peripheral vitreous fibrils. However, these peripheral vitreous fibrils were not easily incised, and the peripheral retina cannot be carefully examined for retinal tears in our procedure. The larger nuclear fragments were more likely to pull on peripheral anterior vitreous gel, thus increasing the risk of a retinal tear. So we excluded cases with nuclear fragments greater than one-fourth the size of the lens nucleus. We also excluded cases without a posterior vitreous detachment (PVD) because we believed that creating a PVD with a low cutting rate has a high risk of producing retinal tears and detachments, and so we performed the core vitrectomy without having to create a PVD.
The eye with a final BCVA of 0.4 had an ERM, and we believe it was the cause of the decreased BCVA. We excluded eyes with a history of retinal detachments because they were at a higher risk of retinal detachments, which our procedure cannot treat.
Because a good view is necessary, only cases with a sclerocorneal incision were suitable for this technique. For the core vitrectomy, the vitreous cutter must be inserted more vertically, which tended to create corneal folds that can reduce the intraoperative view of the surgical field. To overcome this, we expanded the inner part of the sclerocorneal incision from the usual 2.75 mm to approximately 4 mm or more in length; however, the outer part was 2.75 mm, which eliminated the need of profuse irrigation of the vitreous cavity during anterior and core vitrectomy. We also did not use our procedure in cases with a corneal incision because the Oshio wide-field lens would overlap it.
In our cases, the corneal endothelial cell loss (28.0±14.9%) was higher than that reported after PPV phacofragmentation. We believe that this was because the lens nuclei in our cases were harder than those during PPV phacofragmentation. Another possible reason was that there was more manipulation in the anterior chamber while suturing the intraocular lens to the ciliary sulcus in two eyes.
If an ophthalmological surgical illuminator is not available, then a strong light source, for example, operating microscope light fibre can be used.
In conclusion, we present a technique for removing dislocated lens fragments that are smaller than one-fourth the size of the lens nucleus through the sclerocorneal incision made for cataract surgery. This technique does not require a second surgery or the body of instruments for vitreal surgery. Our method may not be a safe alternative to PPV due to the small study number of six eyes. A larger number of cases is needed to assess its safety fully, in particular for retinal tears and detachments.
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