surgery in 94 eyes of 93 patients who presented with a pseudophakic ... No effort was made to control these two series. They were not matched by ... make accurate examination of the retinal periphery difficult, if not impos- sible. In many ... tion and the onset of symptoms suggestive of retinal detachment was calculated for ...
PSEUDOPHAKIC RETINAL DETACHMENT BY William S. Hagler, MD INTRODUCTION
THE
RATE OF CATARACT SURGERY IN THIS COUNTRY DOUBLED BETWEEN 1965 AND
1977 and the aggregate number of operations performed tripled to 350,000 by 1977.1 It has been estimated that a further dramatic increase has occurred and 550,000 cataract extractions were performed during 1981. The exact figures are not available but approximately 63% of these have some type of intraocular lens (IOL) implanted at the time of surgery.2 Therefore retinal surgeons can expect a rapid and progressive increase in the number of pseudophakic detachments referred for surgery. Tasman and Annesley3 published their original article describing their results of retinal detachment surgery in seven patients with Ridley lens implants in 1966. Only recently however have any large series of retinal detachments in patients with modern IOLs been published.4-" All of these publications except Wilkinson's1l report relatively small numbers of patients and therefore analyses and statistical studies have not been meaningful. Freeman et al12 reported a large collaborative series of 252 patients, but this comprised patients operated at ten different centers by a variety of surgeons. The purpose of this study is to report the results of retinal detachment surgery in 94 eyes of 93 patients who presented with a pseudophakic retinal detachment (PARD). All of these eyes were operated on by me or my partner, William H. Jarrett II during the five year period from 1977 through 1981. The major clinical data will be tabulated and compared with a similar retrospective series of 94 eyes operated for aphakic retinal detachment (ARD). These records were chosen at random from 3118 aphakic retinal detachments in a series of 5437 eyes operated for retinal detachment. No effort was made to control these two series. They were not matched by age, race or sex, but they were all operated on during the same five year period which does tend to control the type of surgical procedure utilized as well as the preoperative and postoperative care administered. TR. AM. OPHTH. SOC. vol. LXXX, 1982
46
Hagler
It is important to state from the outset that this analysis of PARD will not allow us to make any conclusion as to the incidence of retinal detachment in pseudophakic eyes, or for that matter, in aphakic eyes. Therefore we cannot draw any conclusion regarding which specific IOL or which type of surgical procedure will result in the lowest incidence of retinal detachment. We did hope we would be able to determine if anatomic or visual results were influenced by the type of IOL utilized. It has been well documented that problems with ophthalmoscopy occur with all types of IOLs and these problems vary with the type of lens used, the ability of the pupil to be dilated, the presence of residual cortical material, and any capsular opacification.3'6"12"13 In many iris supported lenses, whether sutured or not, full dilatation of the pupil may result in complete or partial dislocation of the lens. Even posterior chamber lenses can be dislocated into the vitreous or trapped into the anterior chamber, and in fact this occurred in two patients in this series. Reflections from the lens surfaces, along with distortions and, reflections from the haptics, can make accurate examination of the retinal periphery difficult, if not impossible. In many instances the best view of the retinal periphery is obtained under anesthesia when intense scleral depression can be utilized. MATERIALS AND METHODS
The PARD group consists of 94 eyes in 93 patients on whom we operated for retinal detachment during the years 1977 to 1981. During this period of time five additional patients with PARD were deemed to be inoperable and they are not included in this series. All patients had a standard preoperative evaluation prior to surgery with special emphasis on slit-lamp examination of the anterior segment and vitreous and the preparation of a detailed large scale fundus drawing using the stereoscopic indirect ophthalmoscope. Visualization was so poor that ultrasonography was necessary for diagnosis in four patients. The charts in both groups were reviewed and the following data tabulated: the duration of the detachment prior to surgery, the length of time between cataract surgery and development of retinal detachment (latent period), the type of lens implant, major vitreous pathology such as incarceration and membrane formation. From the drawings and initial evaluation it was determined whether there were one or more star-folds and whether there was enough periretinal proliferation present to classify the detachment as having massive periretinal proliferation (MPP). The preoperative and postoperative vision was compared, the number of months follow-up recorded, the surgical results tabulated as well as the number of
47
Retinal Detachment
surgical procedures performed on each patient. Although the major postoperative complications were listed, no effort has been made at this stage to contact all of these patients or their referring ophthalmologist regarding development of any late complications and we assume some late complications and even redetachments have occurred. All of these patients have been followed at least six months from the time of their surgery. RESULTS
In the pseudophakic retinal group there were 58 males and 35 females producing a male/female ratio of 61%/39%. The ages ranged from 35 to 90 with an average age of 69 years. In the ARD group there were 94 eyes in 94 patients with a similar male/female ratio of 57%/43%. The ages ranged from 32 to 79 with an average age of 63 years (Table I). The period of time between the lens implantation or the cataract operation and the onset of symptoms suggestive of retinal detachment was calculated for both series of patients. In the pseudophakic group the latent period was 13 months compared with 38 months in the aphakic group (Figs 1 and 2). The latent period was longer than one year in only 41% of the PARD compared with 62% of the ARD. Approximately onethird of the patients in the PARD group did not develop a retinal detachment until two or more years after surgery. Twenty-two of the 94 patients with ARD developed retinal detachment six or more years after cataract surgery. Therefore, this indicates that pseudophakic patients will have to be followed for a prolonged period, at least six years before the true incidence of retinal detachment can be determined. The age of the patient at the time of retinal detachment surgery was compared in the two groups and was found to be similar except that the PARD group had slightly more patients who were over 70 years of age (40 vs 30) than in the ARD group. This probably is accounted for by the fact that IOLs are typically utilized more frequently in elderly patients (Figs 3 and 4). TABLE I: COMPOSITION OF GROUPS
PARD
Eyes operated
Males Females Average age
ARD
NO.
%
NO.
%
94 58 35
100 61 39
94 54 40
100 57 43
69
63
48
Hagler Latent Period from Lens Extraction to Retinal Detachment
18163
14-
X.
12-
w
10-
i
8642.3
.5
1
2
3
4
5
6
7
8
9
10
11
1
2
3
YEARS
MONTHS
FIGURE 1
Pseudophakic retinal detachment.
Latent Period from Lens Extraction to Retinal Detachment
En
w w r.
0 m w
9 i
FIGURE 2
Aphakic retinal detachment.
4
5
49
Retinal Detachment PATIENTS EACH DECADE
55504540-
35f
30-
25-
2015105-
. 0-10
11-20
21-30
31-40
41-50
' 51-60
61-70
OVER 70
61-70
OVER 70
YEARS
FIGURE 3
Pseudophakic retinal detachment.
PATIENTS EACH DECADE
55-
5045405)
35-
HI
30-
E-4
°'
25201510-
50-10
11-20
21-30
31-40
41-50
YEARS
FIGURE 4
Aphakic retinal detachment.
51-60
50
Hagler
6055-
5045-
4035-
X o
35-
z
20-
3025-
1515-
5-
IImm .3
.5
1
2
3
4
5
6
7
8
9
10
11
1
2
3
4
5
YEARS
MONTHS
FIGURE 5
Pseudophakic retinal detachment.
The duration of the detachment was estimated from the patients symptoms. Approximately 85% were operated within the first month. There was no significant difference in the duration between the two groups (Figs 5 and 6).
60-
DURATION OF DETACHMENT
555545-
40-
O
3525-
I
.3
.5
1
2
3
4
5
6
7
8
9
10
11
1
2
3
YEARS
MONTHS
FIGURE 6
Aphakic retinal detachment.
4
5
51
Retinal Detachment
A wide variety of lens implants were encountered in this series. The majority, 56, had some type of iris supported lens, but the actual type of iris supported lens was not tabulated nor have we analyzed the results and complications in relation to whether or not the posterior capsule was intact. Twenty-five eyes had some type of anterior chamber lens and in ten eyes posterior chamber lenses were present. In three eyes the type of lens was not recorded. The surgical results were correlated with the type of implant used and as shown in Table II, the type of lens had no effect on the surgical results. In fact, the rate of reattachment in the total group of pseudophakic patients was 91% compared with 93% in the ARD group. We did not analyze whether or not the capsule was intact or whether a capsulotomy was done at the time of surgery or at some period of time
following surgery. There were 86 eyes successfully reattached and 8 failures in the PARD group compared with 87 reattachments and 7 failures in the ARD group. In pseudophakic eyes the vitreous contained varying numbers of cells and was described as "hazy" in 25% of all patients. In the pseudophakic eyes the patients vitreous was attached to the cataract wound in 15%. A vitreous membrane was present in 12%. In addition, one or more starfolds were present in 16% and MPP was described in 9%. In contrast in the ARD group vitreous incarceration was noted in only 6%, vitreous haze in 5%, membranes in 3%, star-folds in 16% and MPP in 5%. Because of the problems with ophthalmoscopy and/or vitreous organization a variety of surgical procedures were necessary prior to performance of the definitive retinal detachment surgery in a large number of pseudophakic patients. In four instances the IOL had to be removed. In five a surgical iridectomy using vitrectomy instruments was necessary, and in six removal of a retrolenticular membrane was performed. In an additional six patients a complete pars plana vitrectomy with removal of vitreous and epiretinal membranes was necessary because of severe MPP. In nine patients pars plana vitrectomy was necessary subsequent to TABLE II: PSEUDOPHAKIC RETINAL DETACHMENT
TYPE LENS
NO.
% SUCCESS
Anterior chamber Posterior chamber Iris plane Not reported
25 10 56 3
92 90 92 100
Total
94
91
52
Hagler
the initial retinal detachment procedure due to low-grade endophthalmitis in two patients and severe MPP in seven patients. In contrast, in the ARD group in iridectomy or membranectomy was required in only three patients and a postoperative pars plana vitrectomy in two patients. Three patients in this group underwent subsequent vitrectomy following late development of MPP postoperatively. Laser mydriasis was utilized in three instances. The eventual surgical results were excellent and statistically similar in both groups. The retina was anatomically reattached in 91% of the PARD group and 93% of the ARD group. However, as detailed above, 30 additional surgical procedures were necessary in the PARD group compared with 7 in the ARD group to effect this anatomic reattachment. This is a statistically significant difference. All of the patients in the PARD group who failed to reattach developed severe MPP. There were a variety of causes for operative failure in the seven patients in the ARD group, but most of them also developed MPP. All of these patients have been followed at least six months and the majority have been followed longer than one year. However, we have made no special effort to obtain late follow-up on patients who are being followed by referring ophthalmologists. The preoperative and postoperative visual acuity was available in all but four patients in each series. These are shown for these patients reattached in Figs 7 and 8. A refraction was not performed on most patients but the visual acuity with pin-hole was recorded. These results can be summarized by stating that in the pseudophakic group of patients the preoperative visual acuity was 20/200 or less in 78% and of these 28% obtained a final acuity of 20/50 or better. In the aphakic group the preoperative visual acuity was 20/200 or less in only 45% and 22% obtained a final vision of 20/50 or better. Although 37% of the entire group of PARD patients obtained vision of 20/50 or better compared with 45% of the ARD group, this is of no significance since in 86% of the PARD group the macula was detached compared with only 55% in the ARD group. In summary, we cannot demonstrate a significant difference in visual results since in those patients with reattached retinas the acuity was improved in approximately 75%, unchanged in 20%, and decreased in 3% in both groups. The clinical features of the retinal detachment were similar in the two groups of patients and we therefore will not describe or tabulate the detailed features such as the number, type, size, and location of the tears, the appearance of the macula, the presence or absence of equatorial folds,
Retinal Detachment
LP
cF E4
04
20/200
1
I1a
UM
HN
53
:**
1: * -
0 a0lo6 0
* a 0 6**0* * 0**
0
*e
*
a
-
2
*0
34
* * *0 * * so
-
17
00
.
10
20/400
P1
20/60 20/100
20/40 20/50
5
S.
S..
a
20/15 20/30
5
1 20/1520/30
20/4020/50
20/60- 20/20020/100 20/400
HM
LP
UN
82
POSTOPERATIVE No. IMPROVED
61
( 79 %)
NO. SAME
17
(16 %)
NO. DECREASED
4
(
5
%)
FIGURE 7
Pseudophakic retinal detachment.
whether the ciliary epithelium was detached. A total retinal detachslightly more prevalent in the ARD group, 31% compared with 22%, and the detachment was limited to one quadrant or less more frequently in the PARD group, 21% compared with 8%. Although tears were not detected preoperatively in some 15 patients with PARD, in all but 2 we were able to demonstrate one or more tears at the time of or
ment was
surgery.
The major complications were definitely higher in the PARD group as shown in Table III. Macular puckers occurred three times more frequently as did vitreous membrane formation and MPP. The lens became dislocated in five patients and all but two of these were replaced by closed procedures.
Hagler
54
POSTOPERATIVE No. IMPROVED
60
( 72 %)
NO. SAME
21
( 25%)
NO. DECREASED 2
FIGURE 8
Aphakic retinal detachment.
TABLE III: COMPLICATIONS 94 EYES
Failure to reattach Macular pucker Vitreous membranes Corneal dystrophy Dislocation of lens Multiple procedures
Endophthalmitis
PARD
ARD
8% 12% 14% 4% 5% 15% 1%
7% 4% 2% 1% 0% 11% 0%
(
2%)
Retinal Detachment
55
DISCUSSION
This report does not provide any information as to the incidence of retinal detachment following IOL implantation or even if the incidence varies with the type of lens utilized or the method of surgery performed (intracapsular vs extracapsular cataract extraction). Scheie et al'4 recently summarized some 20 articles with an incidence of retinal detachment following lens extraction without IOL implantation from 0.8% to 2.3%. Several recent publications of series of cataract extractions with IOL implants have shown a slightly smaller incidence of retinal detachment A posterior chamber lens is a relatively varying from 0% to 1.8%. 7 new procedure and none of these reports contain a significant series to determine if the incidence of retinal detachment using the posterior chamber lens will be the same. Our data show that a large number of patients do not develop detachment until six years or later following cataract surgery and this indicates that it will be necessary for pseudophakic patients to be followed for a prolonged period of time, at least up to six years, before the true incidence of detachment can be determined. Kratz2 estimates that 55% of all IOLs are posterior chamber, 35% anterior chamber and only 10% iris plane. Assuming that lens implant surgeons follow the multicenter's guidelines12 and do not insert lenses in patients with tears, lattice degeneration, or previous retinal detachment in either eye the majority of high risk patients would not have a lens implanted and should have a lower incidence of PARD. Also, Clayman et al16 have shown in a limited series of patients with IOLs that virtually all retinal detachments occurred in eyes with an axial length greater than 25 mm and lens implants presumably are not utilized as frequently in the eyes with this degree of myopia. To date there have been no series with adequate follow-up to calculate incidence of retinal detachment in relation to patients who underwent posterior chamber lens implantation using extracapsular techniques. Binkhorst et al15 have reported a series of 600 eyes with iris supported lens with intact capsule. None of these had developed a detachment at the time of publication. Although only a small percentage of patients undergoing cataract extraction, with or without lens implantation, develop retinal detachment, it must be stressed that 40% of all patients who present to us with retinal detachment are aphakic. Therefore, aphakia is the most commonly associated condition, if not the actual cause, of retinal detachment. Therefore, the act of removing a lens by whatever technique will increase the risk of
56
Hagler
future development of retinal detachment by at least 65 times.18 Hopefully, careful evaluation of large series will eventually enable us to determine if variations in technique will influence this rate. We did not make any attempt to quantitatively grade the degree of interference with ophthalmoscopy. However, I can categorically state that ophthalmoscopy is indeed considerably more difficult and time consuming in most patients with intraocular lenses. Many other authors4'7-9"12"13"17"19 have stressed the problems produced by reflection from surfaces of the lens, poor pupillary dilatation, capsular and cortical lens remnants, and reflections from the haptics. In addition to this there is an increased incidence of retropupillary membranes, severe vitreous haze, and vitreous membrane formation. We found these problems were greatest in iris supported lenses, and were reduced markedly in anterior chamber and posterior chamber lenses. As mentioned earlier, we found no significant difference in the clinical characteristics of the detached retina in patients with pseudophakic detachment compared with aphakic detachment, and therefore we conclude that the mechanisms for production most likely were similar. Both ARD and PARD were characterized by multiple small horseshoe tears located near the ora, along a prominent fold representing the posterior detachment of the vitreous base. These were most frequently located in the superior quadrants. However, the vitreous changes, as manifested by vitreous haze, star-folds, MPP, and vitreous incarceration were statistically more frequent is the PARD group and we speculate this is related to increased inflammation produced by either the lens implant or residual lens material or both. Perhaps there was a greater incidence of vitreous loss and we plan to investigate this in a subsequent study. We feel the six year increased average age of the PARD patient, 69 years, as compared with 63 years in the ARD patient is explained by the fact that intraocular lenses are characteristically used more frequently in elderly patients. We anticipated that the duration of detachment in the PARD group would be less because a large group of unilateral aphakic patients do not wear corrective lenses, and therefore recognition of an early retinal detachment would tend to be delayed. This would also explain the increased incidence of detachment limited to one quadrant in pseudophakic patients. However, the duration was found to be similar in each group. Presumably the difficulty with ophthalmoscopy has some bearing on the fact that the macula was detached in a significantly greater number of eyes in the PARD (86%) than the ARD (55%) group. There were eight patients in whom we could not determine whether the macula was de-
Retinal Detachment
57
tached until after the pupil had been enlarged or vitreous membranes removed. We have no explanation for the fact that the ratio of males to females in both groups of patients was significantly higher than that of the general population. In a previous study we noted that males outnumbered females in phakic retinal detachments 56% to 44%.2O All authors have noted a high incidence of males in both aphakic and pseudophakic detachment groups. We can find no evidence to indicate that males undergo a higher rate of cataract surgery. Perhaps males are more subjected to trauma and this could possibly account for the high ratio of males in the detachment series. The patients in these two groups were treated by similar surgical methods; approximately 60% of each group had scleral buckling procedures performed with encircling silicone bands using cryocoagulation. Twenty-five percent had segmental buckling procedures and the remainder were treated with air or gas injection without buckling procedures. However, as mentioned earlier, a significantly larger number of patients in the PARD group required supplemental surgical procedures. The increased incidence of star-folds, vitreous membranes and MPP in PARD patients tends to indicate that there probably is an increased inflammatory response in this group, especially since most surgeons abort IOL insertion if vitreous loss occurs but we cannot document this in the present report. We have not correlated those vitreous findings with the type of lens utilized but suspect they were higher in the early years when iris supported lenses were more frequently utilized. Because of the difficulty in ophthalmoscopy in pseudophakic eyes we tend to use longer and wider scleral exoplants and apply cryocoagulation to larger areas of the pigment epithelium, since some areas of the fundus were treated blindly. One of the major disadvantages of treating a pseudophakic detachment is the difficulty of using intravitreal air or gas injections because of the danger of dislocating the implant against the corneal endothelium. However, air injections were performed occasionally by using special techniques which are beyond the scope of this paper. Visual results in-the two groups obtaining reattachment showed no statistically significant differences. Five percent of the PARD group had a loss of vision compared with 3% in the ARD group and 73% vs 79% of the two groups obtained visual improvement following surgical reattachment. Approximately one in four patients whose preoperative vision was 20/200 or less obtained postoperative vision of 20/50 or better in each group and in summary there was no statistical difference in the degree of visual improvement between the two groups.
58
Hagler
Our preliminary results indicate complications were more frequent in the PARD group and these consisted primarily of macular pucker, corneal decompensation, and recurrent detachment (Table III). However, we plan to perform a detailed long term follow-up on this group of patients before making any definitive statements regarding complications. CONCLUSIONS
In summary, a study of 94 eyes operated for PARD revealed many similarities to a comparable group of ARD patients. The duration of the detachment, the high incidence of males, and the average age, were all statistically similar. The duration between the cataract surgery and the development of retinal detachment was statistically greater in ARD but this is probably explained by the fact that IOL surgery is a recent development. The macula was detached significantly more frequently in PARDs and the detachment was limited to one quadrant or less more frequently in this group of patients. Vitreous involvement as manifested by severe vitreous haze, vitreous membrane formation and periretinal organization was statistically more frequent in the pseudophakic eyes. Therefore, pseudophakic detachments required multiple surgical procedures both preceding and following the scleral buckling procedure. However, the final anatomical rate of reattachment was approximately 92% in each group and the amount of visual improvement was essentially the same. Although we do not have supporting data there is no doubt but that ophthalmoscopy is much more difficult in pseudophakic patients and this is one of the reasons why multiple surgical procedures were required in 30 instances. We anticipate that the decreasing frequency with which iris plane lenses are being used at the present time will reduce this difficulty. Perhaps serious vitreous changes will also be less frequent.
1. 2. 3. 4. 5.
REFERENCES Taylor J: Medicare payments and changes in the rate of cataract extraction. Ophthalmology 88:41A-46A, 1981. Kratz R: Personal communication, May, 1982. Tasman W, Annesley WH: Retinal detachment in prosthetophakia. Arch Ophthalmol 75:179-188, 1966. Johnson GP, Okum E, Boniuk I, et al: Pseudophakic retinal detachment. Mod Probl Ophthalmol 18:499-502, 1977. Jungschaffer OH: Retinal detachment and intraocular lenses. Int Ophthalmol Clin 19:125-137, 1979.
Retinal Detachment
59
6. Snyder WB, Bernstein I, Fuller D, et al: Retinal detachment and pseudophakia. Ophthalmology 86:229-238, 1979. 7. Norton EWD: Management of retinal detachment in patients with intraocular lens (Copeland model of the Epstein lens). Trans Am Acad Ophthalmol Otolaryngol 81: 135-136, 1976. 8. Curtin VT: Retinal detachment surgery following intraocular lens implantation. Trans Ophthalmol Soc NZ 30:45-46, 1978. 9. Mertens DAE, Zivojnovic R, Baarsma GS: Retinal detachment and pseudophakos. Doc Ophthalmol 48,2:267-271, 1979. 10. Tanenbaum HL: Retinal detachment and pseudophakia. Can J Ophthalmol 14: 249-252, 1979. 11. Wilkinson CP: Retinal detachments following intraocular lens implantation. Ophthalmology 88:410-413, 1981. 12. Freeman HM, Dobbie JG, Friedman MW, et al: Pseudophakic retinal detachment. Mod Probl Ophthalmol 20:345-353, 1979. 13. Freeman HM: Discussion of presentation by Dr William Snyder, et al. Ophthalmology 86:239-241, 1979. 14. Scheie HG, Morse PH, Aminlari A: Incidence of retinal detachment following cataract extraction. Arch Ophthalmol 89:293-295, 1973. 15. Binkhorst CD, Kats A, Tjan TT, et al: Retinal accidents in pseudophakia-intracapsular vs extracapsular surgery. Trans Am Acad Ophthalmol Otolaryngol 81:120-125, 1976. 16. Clayman HM, Jaffe NS, Light DS, et al: Intraocular lenses, axial length, and retinal detachment. Am J Ophthalmol 92:778-780, 1981. 17. Galin MA, Poole TA, Obstbaum SA: Retinal detachment in pseudophakia. Am J Ophthalmol 88:49-51, 1979. 18. Haimann MH, Burton TC, Brown CK: Epidemiology of retinal detachment. Arch Ophthalmol 100:289-292, 1982. 19. Jungschaffer OH: Retinal detachment after intraocular lens implants. Arch Ophthalmol 95:1203-1204, 1977. 20. Hagler WS: Aphakia and retinal detachment. In Emery JM, Paton D (eds): Current Concepts in Cataract Surgery, 4th Biennial Cataract Surgical Congress. St Louis, CV Mosby Co, 1976, pp 333-342.
DISCUSSION DR J. GRAHAM DOBBIE. I am very pleased to be able to discuss Doctor Hagler's paper today and I do appreciate receiving this paper from Doctor Hagler well in advance of this meeting. My first question relates to the time of onset of the retinal detachment. From our own studies, there had been hope that patients with intraocular lenses would notice the onset of retinal detachment earlier than the aphakic patient and before macular involvement because of the better peripheral vision provided to the pseudophakic patient. This was quite obviously not the case in Doctor Hagler's series. Does Doctor Hagler have any thoughts as to why the difference between our findings in which the latent period for the onset of retinal detachment was shorter than a comparable group of aphakic retinal detachments and Doctor Hagler's findings which were just the opposite. In our own series the macula was detached in 75% of the patients which was somewhat better than a comparable series of aphakic patients. However, in Doctor Hagler's series the macula was detached in 86% of the patients which is a distressingly high percentage.
V.0
Hagler
The reattachment rate was better than in our collaborative study. This was probably partly due to the fact that there were less iris supported lenses and, therefore, better visualization of the retina in Doctor Hagler's series. In our own study we could not find retinal breaks in 18% of the cases. This is at least three times greater than a comparative aphakic group of retinal detachments. Probably the cataract surgeons are now doing a better job of clearing the cortical material in the extracapsular extractions and, therefore, there is better visualization of the peripheral retina. Reattaching the retina in the presence of an intraocular lens is obviously more difficult than in an aphakic or phakic retinal detachment. This is shown by Doctor Hagler's data in which approximately one-third of the patients required procedures in addition to the scleral buckling procedure. Nevertheless, Doctor Hagler has achieved a very high rate of success in reattachment of the retina which compares favorably with the aphakic retinal detachment repair. Therefore, if his results are so good, why should the cataract surgeon worry more about retinal detachment in a pseudophakic patient than in his aphakic patients-perhaps they don't. Why does Doctor Hagler list the contraindications to intraocular lenses when the cataract surgeons have retinal surgeons like Doctor Hagler to fall back upon in the event that the patient develops a retinal detachment? The visual results in this series were good. However, Doctor Hagler took a visual acuity of 20/50 for his analysis, and in our series we used a vision of 20/40. We found that there were 5% less patients obtaining 20/40 vision in the pseudophakic group compared to the aphakic group. When vitreous was lost at the time of implant surgery only 17% of the patients regained 20/40 vision or better. One factor in Doctor Hagler's visual results might have been the fact that there were fewer iris supported lenses in his group as compared to our own. With the newer anterior and posterior chamber lenses there seems to be less irritation of the iris. There seems to be less inflammatory response with these lenses and, therefore, fewer precipitates on the lens surface and fewer synechiae. The pupils tend to dilate much better providing a better view of the peripheral retina. There also seems to be less of an inflammatory membrane around the newer lenses. With the old iris supported lenses the iridocyclitis caused pupillary membranes more frequently. These membranes continued into the vitreous and on to the surface of the retina resulting in vitreous contraction and preretinal contraction with wrinkling of the retina. There seems to be less of this problem with the posterior chamber lenses and the newer anterior chamber lenses. This is my clinical impression and I would like to get Doctor Hagler's thoughts on this as well. I wonder if Doctor Hagler found a difference in the type of retinal breaks in the early retinal detachments as compared to those of later onset. One would suspect that when the vitreous was disturbed during cataract surgery, the retinal breaks would be of the larger horseshoe shape type and that the onset of the retinal detachment would come on sooner than those in which there was no vitreous disturbance and that in this latter group, the retinal breaks would be of the typical small aphakic type which are located along the posterior vitreous base. Would Doctor Hagler please comment on this.
Retinal Detachment
61
Along these same lines, the posterior chamber lenses might be expected to prevent forward movement of the vitreous body and thereby prevent traction by the vitreous along its posterior vitreous base. This might prevent the typical aphakic retinal breaks from occurring. Does Doctor Hagler have any thoughts about this question? In our cases we are still seeing both the typical aphakic retinal breaks as well as the phakic type, but we don't have enough cases to make any valid conclusions as to whether or not and to what degree the posterior chamber lenses protect the retina by giving internal support to the vitreous body. I rather suspect that when the posterior capsule has been needled, any protection of the vitreous body offered by the posterior capsule is greatly reduced. Doctor Hagler doesn't report the results in cases of vitreous loss. In our series in those patients suffering vitreous loss at the time of cataract surgery only 17% regained 20/40 vision or better. Therefore, vitreous loss should not be taken lightly in spite of the advances in the surgery of the vitreous. Does Doctor Hagler have any comment on the effects of vitreous loss in his series of patients? Over the past 20 years I have done various procedures to the vitreous which includes attempts to cut vitreous membranes with knives and scissors, injecting silicone oil to peel membranes from the retina and to push the retina back into its more normal position and in the more recent past the various vitrectomy procedures. From experience with these procedures, I have gained rather than lost respect for the vitreous. If I was the type of person to be out demonstrating for a cause, I would be attending all the cataract meetings carrying a banner that would summarize by own feelings about the vitreous in these words, "PRESERVE VITREOUS CHASTITY." DR THOMAS D. DUANE. Doctor Dobbie discussed this paper with regard to visual acuity. I am disturbed to find out that on a national basis across the board the best results that are obtained by the retinal surgeons are 20/40 or less in about 50% or more of the cases. I have seen this statement quoted and maybe it is true, but I believe that anybody who reports on the results of visual acuity, pre- and postoperatively in a patient with retinal detachment should include visual field and visual acuity so that the rest of us can decide whether we believe an advance has occurred or not.
DR HAROLD F. SPALTER. We desperately need some honing in as to whether the claims of the intraocular surgeons, that includes the buccaneers, are diminishing or making passe the need for retinal surgeons. This of course, is a great concern of mine and I would like to ask Doctor Hagler about his retrospective thoughts on intraocular lens types. There seems to be a reverse of the current type of implants and I wonder whether his subset of posterior chamber lenses had less retinal detachment and macular edema than the anterior chamber lens subset? Does this analysis reveal to us any new information that would be useful in looking toward
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Hagler
the future as to whether there is any advantage in implanting posterior chamber lens to the exclusion of anterior? If so, are the potential advantages in preventing aphakic retinal pathology negated by opening the posterior capsule? I would appreciate hearing an answer to those questions based upon your excellent critical review.
DR FRONCIE A. GUTMAN. There are many problems in interpreting reports on the incidence of pseudophakic retinal detachment and the results of their surgical repair. The constantly changing preoperative indications for primary and secondary lens implant surgery are non-standardized and the intraoperative aggressiveness of the surgeon may include an elective vitrectomy to permit lens implantation. The choice of pseudophakos influences the type of cataract surgery (ie, intracapsular vs extracapsular), ability to dilate the pupil, and the clarity of media (ie, residual opacified membranes in extracapsular cataract surgery). Each of these factors may alter the incidence of pseudophakic retinal detachment and the results following attempted surgical repair. Since manipulation of the vitreous increases the incidence of rhegmatogenous retinal detachment, any procedure which includes any form of vitrectomy will introduce an additional risk factor for such an event. If cataract surgeons alter their surgical procedures and become more aggressive, risk factors will be added which are likely to cause an increasing incidence of pseudophakic retinal detachment. DR WILLIAM S. HAGLER. I would like to thank Doctor Dobbie and the other discussants. First, Doctor Dobbie asked if I have any explanation as to why the macula is not protected by the intraocular lens. That is, why was the rate of macular detachment at the time of diagnosis significantly higher in pseudophakic eyes than in aphakic eyes. This is something that anterior segment surgeons told us would not happen. I think that this is related primarily to the fact that although the patient may gain time by earlier recognition of the symptoms of a detachment, the surgeon may lose due to difficulty with ophthalmoscopy. In several of my patients I could not even determine whether the macula was detached or not when I first saw the patient. It was frequently only after the vitrectomy or the membranectomy had been performed that we could adequately examine the eye. My assumption is just that the diagnostic time interval is increased at least in those patients who have poor visualization due to opacification of the media. He also asked if the contraindications to lens implantation are being violated. I really wish someone could state whether an anterior segment surgeon should still follow the contraindications that were presented at the American Academy meeting several years ago. I gather from my own patients and from comments Doctor Gutman made that they really aren't and that vitreous loss is not any longer considered a contraindication. I have to ask someone else to comment on this. I feel that we may be treading on thin ice by going against these contraindications that were very thoughtfully presented several years ago.
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Doctor Dobbie mentioned the fact that breaks were not found in 18% of his series. Actually, in his series and in many instances in my series the best time to examine these patients is on the operating table. We didn't determine breaks initially in a fairly large number and only after the vitrectomy was performed were breaks found. Doctor Spalter asked me if I had any information as to why the results were so good or whether the results varied with the type of lens. Actually, in my opinion the posterior chamber lens and the anterior chamber lens are used more frequently today. In the earlier patients in the series we were having less problems with ophthalmoscopy. We still have some problems but less problems with ophthalmoscopy and I believe with Doctor Gutman that the surgeons certainly are becoming more and more aggressive about secondary lens implants, even implants with vitreous loss, but I just want to close by saying that I don't think these retinal detachment patients can be managed unless the surgeon is really familiar with vitrectomy techniques. I cannot emphasize too strongly that many of these patients require multiple, difficult, time consuming procedures. Not only are the vitrectomy procedures difficult with intraocular lenses but also fluid gas exchange can be extremely difficult and dangerous due to possibility of dislocating the lens against the cornea.
