Year : 1984 | Volume
: 32 | Issue : 6 | Page : 485--487
Pars plana lensectomy-a detailed study
Rajini Kantha, SS Badrinath, Chandran Abraham, Mary Abraham, Manju Kulkarni
Sankara Nethralaya, 18, College Road, Madras, India
Sankara Nethralaya 18, College Road, Madras 600 006
|How to cite this article:|
Kantha R, Badrinath S S, Abraham C, Abraham M, Kulkarni M. Pars plana lensectomy-a detailed study.Indian J Ophthalmol 1984;32:485-487
|How to cite this URL:|
Kantha R, Badrinath S S, Abraham C, Abraham M, Kulkarni M. Pars plana lensectomy-a detailed study. Indian J Ophthalmol [serial online] 1984 [cited 2020 Jan 23 ];32:485-487
Available from: http://www.ijo.in/text.asp?1984/32/6/485/30846
Conventional operations like discission, aspiration an d linear extraction have been employed for the treatment of congenital cataracts and traumatic cataracts in young adults for many years. Phaco-emulsification came into vogue in 1970. A detailed study of pars plana lensectomy with ocutome fragmatome system has been carried out and the advantages enumerated.
MATERIAL AND METHODS
146 eyes of 119 patients with cataract of varying aetiology were subjected to pars plana lensectomy and with ultrasonic fragmatome-ocutome system. 88 of the patients were males and 31 were females. In 27 cases, the procedure was done bilaterally. The surgery was performed between June 1979 and May 1983. Majority of the patients (62.9%) belonged to the 1-20 years age group [Table 1]. The youngest was I month old and the oldest 49 years of age. The various indications for lensectomy has been enumerated in [Table 2]. Congenital and traumatic cataracts, were the most common indications for lensectomy.
A preliminary ultrasonography was done in 96 eyes where there was no view of the fundus in order to assess the condition of the posterior segment, especially the retina. The patient's pupil was fully dilated 12 hours before the surgery with 10% Phenylephrine and 2% Homatropine. The standard pars plana lensectomy procedures were adopted Surgery was performed either under local or general anaesthesia. The sclerotomies were made 3-3.5 mm away from the limbus in adults and 2-2.5 mm away in infants at the 2 and 10 0' clock position at the parsplana. The sclerotomy was then plugged with a scleral plug making the eye ball water tight.
The pre-operative visual acuity is recorded in [Table 3]. Majority of the patients (54.7%) bad a visual acuity of less than 1/60. In infants, who comprised 21.9% of the total number of cases, the visual acuity could not be assessed. Inaccurate projection of light was observed in 2 cases.
Since fundus view could not be obtained in 65.7% cases, due to cataract preoperatively ultrasonography, both A and B scan were performed in these eyes. The anteroposterior diameter of the globe, ruptured lens matter in vitreous cavity (5.44%), vitreous haemorrhage (1.36%) and total retinal detachment (2.05%) were noted.
The complications encountered during the procedure and in the post-operative period are recorded in [Table 5][Table 6]. The most common intra-operative complication was small lens dropping falling into the vitreous cavity (20.51 %). Some of these were retrieved after careful vitrectomy 3. In all cases, the lens matter got absorbed without any residual complications. Accidental sphincterectomy occurred with the ocutome, but this did not cause any significant optical or cosmetic problems. Iritis in the post operative period was mild and resolved with local steroid drops and Atropine. Glaucoma which occurred in 5 cases was transient and subsided within a week, after the administration of acetazolamide.
In immediate post-operative period lens dropping and vitreous haemorrhage were the most common complications. In 2 cases, rhegmatogenous retinal detachment occurred 7 months and 14 months after the operation during the follow-up period. In both the cases scleral buckling operations were performed and the retina got attached. Out of these two, one had a redetachment after a period of l2 years. Revision scleral buckling was done for this eye which did very well in the post-operative period. The final visual acuity in the first case was 6/5, N/6 with contact lenses and in the second case 6/9, N/6 with suitable spectacle correction In another case, lensectomy was performed for traumatic cataract in the right eye. The 4±'hard nucleus got dislocated posteriorly and all efforts to retrieve it failed. This patient developed small retinal holes in the posterior pole which caused a total retinal detachment in that eye.
Pars plans lensectomy with an ultrasonic fragmatome ocutome system is one of the latest advances in cataract surgery. In cases of congenital cataracts and cataracts in young adults where an intracapsular cataract extraction is contraindicated, lensectomy can be the procedure of choice. Complications like after cataract, vitreous loss, bullous keratopathy. epithelial down growth, anterior synechiae, secondary glaucoma and wound dehiscence which are met with during conventional surgery are either absent or seen in significantly small numbers, after parsplana lensectomy. Since this procedure utilizes a small scleral incision and a closed system to maintain intraocular pressure during the surgery, pre-operative reduction of intraocular pressure is not necessary. Early ambulation of the patient is possible since no corneo-scleral section has been made. The most important advantage of this procedure is that vitreous loss does not occur. Lensectomy can also be done in cases where vitrectomy or scleral buckling procedures are indicated in order to obtain a clear media, if the lens is cataractous.
Powerful suction of 8 mm Hg was needed. High energy levels were required. A power setting of 9 or 12W was found sufficient. It is not possible to remove the anterior and posterior capsule with the fragmatome. Lens with 3+ or 4+ nuclear sclerosis are not suitable for fragmentation. Fragmatome is superior to ocutome especially in cataracts with l+ or 2+ nuclear sclerosis. Ultra sonification is a much faster process than lens removal with only ocutome. It is impossible to fragment lens, if vitreous gets mixed with lens matter.
In soft cataracts without any nuclear sclerosis, like in congenital and traumatic cataracts, the entire lensectomy procedure can be carried out independently with the ocutome. without the help of fragmatome. The ocutome pore size is kept at the maximum to facilitate easier and faster removal of lens material.
In this series, 146 eyes of 119 patients were subjected to parsplana lensectomy with ultrasonic fragmatome-ocutome system. It has a definite role in cases where a vitreous loss is inevitable with conventional techniques.
|1||0' Malley, C., 1977. The Ocutome news letter, 2:3|
|2||Benson, W.E., Blankenship, G.W, and Machemen. R., 1977. Amer. J. Ophthalmol., 84; 150.|
|3||0' Malley, C., 1977, The Ocutome news letter,2:3|
|4||Girad, L.J. 1979, Ultrasonic Fragmentation for Intraocular surgery, Vol. 1, C.V. Mosby Co., St Louis, Missouri.|
|5||Abraham, M. and Kulkarni, M. 1982 All Ind. Ophthalmol Conf, Calcutta.|
|6||Charles, S., 1980, The Ocutome news letter., 5;3.|