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ARTICLES
Year : 1978  |  Volume : 26  |  Issue : 4  |  Page : 1-12

Retraction of the upper lid in oculo-orbital sockets


M. U. Institute of Ophthalmology, Aligarh, India

Correspondence Address:
Gopal Krishna
M. U. Institute of Ophthalmology, Aligarh
India
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Source of Support: None, Conflict of Interest: None


PMID: 374272

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How to cite this article:
Krishna G, Nath K, Shukla B R, Gogi R. Retraction of the upper lid in oculo-orbital sockets. Indian J Ophthalmol 1978;26:1-12

How to cite this URL:
Krishna G, Nath K, Shukla B R, Gogi R. Retraction of the upper lid in oculo-orbital sockets. Indian J Ophthalmol [serial online] 1978 [cited 2021 May 8];26:1-12. Available from: https://www.ijo.in/text.asp?1978/26/4/1/31494

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Table 1

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Table 1

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Retraction of the upper lid following loss of the eyes is of frequent occurrence. This problem has attracted very little attention in literature in the past and the literature on the subject is scanty, even though the problem is encountered very frequently.

In the present study of thirty cases, an attempt has been made to evaluate these cases of lid retraction after various surgical procedures such as liquid silicone injections, silicone sponge implant, skin or mucous grafting, and superior border built up prostheis.

Various causes of upper lid retraction have been summarized in [Table - 1]. In order to correct this disfigurement, various surgical treatments have been experimented from time to time and few adopted [Table - 2].

With so many debatable factors causing the retraction of the upper lid and multifarious treatments, one gets lost as to the line of treatment to be adopted in a particular case. Ultimately one adopts procedures depending upon ones own ingenunity. Certain broad out­lines emerge out of the 30 cases which we studied and this also happens to be the biggest individual series.


  Materials and methods Top


In the present study, thirty cases which were treated at M.U. Institute of Ophthalmology, Aligarh have been studied. In every case mode, circumstances and dura­tion of eye loss, use of any implant at the time of surgery was used and the subsequent problems with the prosthesis were recorded. The presence and the extent of enophthalmos was measured with exophthalmome­ter. The depth of the upper lid retraction was measured as follows:

A straight edge of the scale was placed across the centre of the superior and inferior orbital margins. From the back of this straight edge a narrow scale caliberated in millimetres was pressed posteriorly until it just touched the skin of upper lid sulcus in its deepest part [Figure - 1]. This antero-posterior depth was recorded on both sides. Measurement of retraction was again repeated at the end of post operative period and was compared with the original.

Conjunctival culture and biopsy of conjuntiva and levator muscle was also taken during the surgical procedure.

In all cases one or a combination of the following procedures was adopted [Table - 3]:

(1) Mucous membrane epidermal graft.

(2) Injection of liquid silicone.

(3) Implants of silicone sponge in the lids.

(4) Superior border build up artificial eye.

(1) Mucous membrane or epidermal graft:

In cases of contracted sockets, the cavity was lined partially or completely either by buccal mucous mem­brane grafts or epidermal grafts.

(2) Injection of liquid silicone:

Liquid silicone (Demethyl polysiloscone) of 100 cS viscosity was used. The liquid silicone was sterilized in hot air even at 160°C for one hour. 1 to 5 cc of silicone liquid was injected at the apex of the orbit, through the skin over the lateral palpebral ligament. Mechanical pressure over the injection area was maintained for 6-8 hours and patient was kept in supine position for 4 hours. Pressure bandage was applied for 4 days in order to permit the liquid to distribute itself evenly.

(3) Silicone sponge implants (Silastic-S9711 of Dow­corning):

Starting at temporal end of the eyebrow, a 15 mm oblique incision slanting slightly outwards was made. A similar oblique incision slanting medially was made below the nasal end of the eyebrow [Figure - 2]. A long narrow blunt pointed pair of scissor was introduced under orbicularis muscle from the outer incision and a tunnel was thus fashioned just below the eyebrow from the outer incision to the medial one. A 2-3 cm long strip of silastic-59711 was taken and passed from the temporal to the nasal end. The ends of the tube shaped implant were conical and were tucked, excised or burned. The wound was closed at both ends with a 4.0 plain catgut suture and the skin with 6.0 silk sutures [Figure - 3],[Figure - 4],[Figure - 5].

Local application of antibiotic ointment, in the bandage was applied and skin sutures removed on 7th post operative day.

(4) Superior border build up artificial eyes:

Acrylic conformers of varous sizes were kept in ready stock. These conformers were modified in shape and size according to needs of the socket. If additional thickness was required, the modelling was added, when necessary to increase the bulge [Figure - 6]. Repeated trials were necessary to achieve the desired results. Once the desired shape and size was achieved, the model was duplicated as superior border build up artificial eye [Figure - 7].


  Observation Top


In this series, 30 cases of sockets with restriction of the upper eye lid were studied. Their clinical observations were as under:

The age of the patient varied from 13 to 66 years affecting 21 males and 9 females. The age of the patient could roughly be divided into two age groups viz (1) younger age group from 16 to 26 years (17 patients). (2) middle age group from 32 to 45 years (13 patients). The number of females in the younger age group was twice the number in the middle age group as a large number of cases prefer to come when the question of marriage becomes imminent.

The left eye was involved in 24 patients while the right eye was affected in 6 cases. 12 patients complained of absence of space for prosthesis, 7 were not satisfied with their cos­metic appearance, 6 had discharge from their sockets while in 5 the prosthesis did not fit properly. Considering the cause of the eye loss, the commonest was trauma (9 perforating and 4 chemical injuries), followed by endophthal­mitis (7 cases), panophthalmitis (6 cases), retinoblastoma (3 cases) and anterior staphyloma (1 case). The duration between the eye loss and time lapsed when the patient reported for treatment in cases of lid retraction varied from 28 days to 45 years.

To exclude any bony pathology, x-ray examination was carried out in 11 cases. In one case there was a fracture of the floor of the orbit with haziness of the corresponding maxil­lary sinus, while in the remaining 10 x-ray were normal. In the remaining cases x-ray examin­ation was not considered necessary.

All 30 cases were studied for bacterial and fungal infections of the socket. Ten cases were sterile and 20 were infected. [Table - 4].

Fibrous tissue bands with conjunctiva (11 cases) and muscles biopsy from the levator palpebre superioris (8 cases) revealed the following changes:

(a) Changes in Conjunctiva:

Conjunctival epithelium was found to be hypertrophied [Figure - 8] without any evidence of keratinisation (7 cases). There was epithelial odema (3 cases), and complete absence of goblet cells in 4 cases. In one case, epithelium was dipping into subepithelial region. Increased amount of fibrosis under the epithelium was a prominent histological finding in 10 cases. In 8 cases there were aggregations of chronic inflamatory cells in the form of lymphocytes, monocytes and plasma cells. In one of these cases there was granuloma formation marked by epitheliod cells, giant cells and lymphocytes without any areas of cassation. Apart from chronic cellular infilterates, lymphatics seemed to be dilated in three cases.

In one case there was polymorphonuclear response under the epithelium alongwith dilatation of blood vessels with prominent endothelium.

(b) Changes in the muscles:

Increased amount of fibrous tissues in the muscle (6 cases) was a common finding [Figure - 9]. Other changes such as central displacement of the sarcolemma nuclei, absence of cross striation and fragmentation of the muscle fibres, were present in 5 specimens, thereby suggesting degenerative changes. There was no evidence of inflammation in any of the section.

Among the 30 cases under study, sockets were contracted in 22 cases. In 12 cases epider­mal graft [Figure - 10],[Figure - 12],[Figure - 13] were given. This resulted in improvement in retraction of the upper lid as in [Table - 5]. However, in none of the cases complete cure takes place. In 11 cases associated deep set socket could not be corrected.

Liquid silicone was injected in 12 deep set sockets and the amount of liquid silicone varied from 2-5 cc. Although it corrected depth of the socket and upper lid retraction to a great ex­tent yet some element of lid retraction was found to be present in every case. Average improve­ment in different amount of silicone injected is given in [Table - 6].

In 2 cases, effect of liquid silicone disappeared within 2 weeks and injection was repeated in these cases. Some complication following injec­tion was noted in the form of ptosis (1 case), decrease in vertical height (2 cases) and dis­appearance of infratarsal sulcus of lower lid in 4 cases.

In 5 cases tubular sponge was implanted [Figure - 12],[Figure - 13], this resulted in correction of retraction of the upper lid in 4 cases the degree of correction varied from 7 to 9 mm. In one case silicone implant was rejected.

In order to correct residual retraction, superior border build up artificial eye are given in 29 cases. Thickness of the superior border varied from 2 to 8 mm and the results are tabulated in [Table - 7].


  Discussion Top


The retraction ranged between 4 and 27 mm with an average of 13.7 mm. In 83.2% cases it fell between 6 to 20 mm and amongst 1/3 cases it was within 6 to 10 mm. The average retraction in the younger age group was slightly more (14.3 mm) as compared to the middle age group (12.1 mm), perhaps due to increased muscle tone in the younger age.

It was more amongst females (16 mm) as compared to males (13.3 mm), while amongst the middle aged females, it was less (9.5 mm) than males (11.5 mm), in same group, showing thereby that age change and atonicity in the females of middle age is much more than amongst males, when perhaps the absorption of fat plays a more decisive role.

The involvement of left eye was four times more than the right one for reasons unknown.

Time interval between the loss of the eye, and the time when the patient first reported for treatment was perhaps immaterial as after a certain period, sometimes the retraction becomes stationary after the contractures have reached the maximum. No direct relationship between the amount of retraction and its duration could be established.

From [Table - 8] it is concluded that irrespec­tive of other factors, if the causes which damage the eye prior to retraction of the upper lid are considered, it is found, that in order of incid­ence, the maximum average retraction is seen in cases of perforating and chemical injuries, than in panophthalmitis and least in cases of retino­blastomas.

According to Allen and Webster[1], post retinoblastoma socket manifest less retraction of the upper lid as there is little or no displace­ment of the tissues downwards due to sudden removal of a large mass from the orbit and its replacement by an implant. Thus the opinion of Allen and Webster[1] stands corroborated by our studies [Table - 8].

Percentage-wise the maximum improvement (86.96%) was observed in cases of endophthal­mitis followed by panophthalmitis (68.0%), perforating injuries (61.9%) and retinoblastoma (60.2%). The maximum improvement was seen in cases of chemical injuries (55.3%), which is understandable as there is a lot of scarring of tissues in these cases [Table - 8].

Faulty artificial eye causing chronic conjunc­tivitis and irritation, could be responsible for retraction of the upper lid in 10 cases. The sequence of events is believed to be as under:

Cracked or rough artificial eye was a constant source of irritation to conjunctiva (6 cases). With the movements of the eye lids there is constant trauma to the conjunctival epithelium, specially in the upper fornix and adjacent areas leading to its chronic inflammation. A lot of scarring (fibrous bands) takes place which restricts the movements of the upper lid, pulling it inferiorly and posteriorly and retracting it as well. The upper fornix gradually gets shallower especially on the medial side.

The heavy glass eye in due course sags the lower lid downwards and consequently, the prosthesis is gradually shifted downwards, thus initiating or exaggerating the existing supratarsal depression, with the displacement and shifting of the tissues. Such a cause of supratarsal depression was present in 2 cases.

If the artificial eye is too large, the obstrution or displacement of the punctum may result in persistent epiphora with consequent conjuctivi­ties and discharge. This may lead to the proliferation of the granulation tissue in the fornices. Two cases presented a picture of this type.

In this group, 3 cases of upper lid retraction reported to us with the sagging of the lower lids. In 2 cases sagging was due to reduced muscle tone of the orbicularis in old age and in one case it was due to heavy glass eye. As a result of sagging of the lower lid, the artificial eye shifted downwards leading to the graviatated the formation of supratarsal depression.[3],[6]

In this study only one case of fracture of the orbital floor with retraction of upper lid (16mm) reported to us. Pfeiffer[33] and Ruddmann[36] have noted and commented upon the retraction of the upper lid, due to displacement of the superior rectus muscle and the orbital contents, to cause the levator to pull directly in the postero-inferior direction simultaneously the orbital septum is also pulled posteriorly by Landstrom's muscle and finally the orbital contents are shifted downwards due to gravity and posteriorly due to muscle tone.

From [Table - 9] it is evident that the best results are achieved in cases where the implants were given at the time of enucleation or eviscer­ation while fairly good results (70-80%) were obtained in cases of simple enucleations, eviscerations and cases where the phthisic eyes were present.

On histopathological examination of the levator palpebrae superioris in 8 cases, increase in the amount of fibrous tissue and degenerative changes of the muscle fibres were the commonest findings. There was no evidence of any inflam­mation in any section of the levator becoming fibrotic, so that its length progressively decreased and in turn it pulls the Landstrom's muscle posteriorly causing further retraction of the upper lid.

Eleven cases showing retraction of the upper lid, had associated fibrous bands in and under the conjunctiva which extends into the upper fornices and upper palpebral conjunctiva. These bands on histopathology showed predominent subepithelial fibrosis.

Subepithelial proliferation of the fibrous tissue, may in itself, be not a primary cause of retraction but its extensive proliferation and subsequent gradual contraction would help its progress.

The organisms isolated from the socket do not appear to have any direct relationship bet­ween retraction of the upper lid and organisms isolated even though the chronic conjunctivitis might have existed or may coexist and which may have even aggravated the proliferation of fibrous tissue.

The cases and problems involved differ so widely with every case that no hard and fast rule can be laid regarding the line of treatment. The more the scarring, duration, lack or absence of tissue, the more drastic is the required treat­ment.

Our results showed that 1.5 mm of retraction of the upper lid was naturally overcome in cases of mucous grafts and 2.4 mm in cases of epide­ramal graft in cases of lid retraction associated with contracted socket.

[Table - 6] shows that for each cubic centimeter liquid of silicone injected, the improvement in the retraction of the upper lid was at least one and half to two times in millimetres. This shows that 4 to 10 mm of retraction can be overcome by liquid silicone alone. Minor complications after silicone injection occurred in 75% of cases which are easily manageable.

Silicone sponges were used in 5 cases of retraction of the upper lid. It was rejected in one case and so had to be removed. In another case it caused ptosis. The cosmetic improve­ment in retraction was achieved almost to the extent of thickness of the sponge used. All these cases required freeing of the contracted or fibrosed levator, which naturally affected the movements of the upper lid.

The superior border buildup Snellen's reform eye attempts to keep the front surface of the eye in a cosmetically acceptable position and with the expectation that the soft tissues of the orbit will be displaced and adjusted around the pros­thesis anteriorly to fill the supra orbital fold and other areas which otherwise appear depres­sed and empty.

Allen and Webster[1] did not state the rela­tionship between the amount of thickness of the superior border buildup eyes and the improve­ment obtained, which we have tried to correlate as under:

[Table - 7] shows that improvement obtained by the superior border build up eye varies from 50 to 100% of the thickness of the superior border of the prosthesis. The average improve­ment in 29 cases is 68% (2/3) of the thickness of the prosthesis upper border.

Complications like sagging of the lower lid and incomplete closure of palpebral fissure were observed in 10 cases (5 each). Adjustment of weight and thickness of the prosthesis relieved the condition appreciably.

Considering all the procedures, best results were obtained in cases where intrascleral or muscle cone implants were given at the time of enucleation [Table - 9]. In others apical injec­tions of liquid silicone should be followed by the appropriate surgery and the residual retrac­tion was corrected by the superior border build up prosthesis. Rarely a tubular silicone sponge would be necessary.


  Conclusions Top


There was no direct relationship between the amount of lid retraction and duration of eye loss, and between the initial disease and the occurence of retraction, but the extent of lid retraction was found in descending order in cases of perforating injuries, chemical injuries, pan and endophthalmitis and least in retino­blastoma.

Faulty prosthesis can also accentute the retraction of the upper lid in a large number of cases.

Sagging of lower lid and fracture of the floor of the orbit can also give rise to the retraction of the upper lid.

There was no close association between the micro-organism isolated from the socket and lid retraction.

Best results were obtained in cases where either a muscle cone or intrascleral implant was given initially.

The improvement in retraction of the upper lid is almost equal to the thickness of silicone tube implanted.

Each cubic centimeter of the liquid silicone gives an improvement of 1.5 to 2.0 mm in retraction of the upper lid.

The average improvement with the superior border buildup eye is about 68% of the thick­ness of the border. The improvement varies from 50-100%.

Epidermal grafting corrects upper lid retrac­tion twice that with mucous grafting in contrac­ted sockets.

Maximum improvement was seen in end­ophthalmitis (86.2%), and then in perforating injuries (61.7%) and was almost the same in re­tinoblastoma (60.7%). It was minimum in cases of chemical injuries due to excessive scarring.

The cases and problems involved differ so widely with every case that no hard and fast rule can be laid regarding the line of treatment. The more of scarring, duration, lack or absence of tissues, the more drastic is the treatment required.


  Summary Top


In this study, the scanty literature on lid retraction has been reviewed and 30 cases evaluated from the point of etiopathogenesis and the amount of retraction produced by various factors. The relief obtained by the various treatments has been evaluated.


  Acknowledgement Top


Our sincere thanks are due to Sri. D. Kumar, Head of contact lens department, Gandhi Eye Hospital, Aligarh for his help and guidance in preparation of moulds and artificial eye etc., in these trials, without which this work could not have been done[59].

 
  References Top

1.
Allen, L. and Webster, H.E., 1969, Amer. J. Ophthal., 67,189.  Back to cited text no. 1
    
2.
Allen, L., Spivey, B.E. and Burns, C.A., 1969, Amer. J. Ophthal., 68, 397.  Back to cited text no. 2
    
3.
Allen, L., 1970, Tr. Amer. Acad. Ophthal. & Otol., 74, 1318.  Back to cited text no. 3
    
4.
Barraquer, 1901, Arch. de. Oftal. Hisp. Amer., 1, 82.  Back to cited text no. 4
    
5.
Berens, C., 1943, Amer. J. Ophthal., 26, 117.  Back to cited text no. 5
    
6.
Bertlett, R.E., 1966, Amer. J. Ophthal., 61, 68.  Back to cited text no. 6
    
7.
Callahan, A., 1966, "Reconstructive surgery of the eyelids and ocular adenexa." Aesculapius, Birmingham, Ala, p 228.  Back to cited text no. 7
    
8.
Colombo. P., 1905, Quoted by Dimitry, T.J., 1944.  Back to cited text no. 8
    
9.
Converse, J.M., 1944, Arch. Ophthal., 31, 323.   Back to cited text no. 9
    
10.
Culler, N.L., 1946, Amer. J. Ophthal., 29,176.  Back to cited text no. 10
    
11.
Davis, J.S., 1917, Ann., Surg. 66, 88.  Back to cited text no. 11
    
12.
De Voe, A.G., 1945, Amer. J. Ophthal., 28, 1346.  Back to cited text no. 12
    
13.
Dimitry, T.J., 1944, Arch. Ophthal., 31, 18.  Back to cited text no. 13
    
14.
Doherty, W.B., 1923, Amer. J. Ophthal., 6, 19.   Back to cited text no. 14
    
15.
Doherty, W.B., 1939, Amer. J. Ophthal., 22, 419.  Back to cited text no. 15
    
16.
Gilles, H.D., 1920, Quoted by Sherman, A.E., 1952.  Back to cited text no. 16
    
17.
Gougelmann, P., 1929, Arch. Ophthal., 2, 76.  Back to cited text no. 17
    
18.
Gougelmann, P., 1937, Arch. Ophthal., 18, 774.   Back to cited text no. 18
    
19.
Grossman, K, 1907, Brit. Med. J., 2, 1223.  Back to cited text no. 19
    
20.
Hill, J.C., & Radford, C.J., 1964, Amer. J. Ophthol., 60, 487.  Back to cited text no. 20
    
21.
Hill, J C., 1967, Proceedings of the second International Symposium on Plastic surgery of the eye and adenexa, Edited by Smith & Con­verse, C.V. Mosby, Sant. Louis. p 439.  Back to cited text no. 21
    
22.
Heneleski, I.S. jr and Shannon, G.M., 1973, Amer. J. Ophthal., 76, 540.  Back to cited text no. 22
    
23.
Jeyes, P., 1892, Quoted by Dimitry, T.J. 1944.  Back to cited text no. 23
    
24.
Lang, W., 1887, Tr. Ophthal. Soc., U.K., 7, 286.   Back to cited text no. 24
    
25.
Lauber, H., 1910, Quoted by Sherman, A.E., 1952.  Back to cited text no. 25
    
26.
Moore, T.I., 1952, Amer. J. Ophthal., 35, 399.   Back to cited text no. 26
    
27.
Muller, F., & Muller, A., 1912, Quoted by Dimitry, T.J., 1944.   Back to cited text no. 27
    
28.
Mules, P.H., 1885, Tr. Ophthal. Soc., U.K., 5, 200.  Back to cited text no. 28
    
29.
Murphey, J.B., 1915, Surgical Clinics, Philadel­phia, 4, 125.  Back to cited text no. 29
    
30.
Murphey, P.J. et al., 1949, Quoted by Bethke, E.G. 1952, Amer. J. Ophthal., 35, 527.  Back to cited text no. 30
    
31.
Paton., 1944, Quoted by Sherman, A.E. 1952.   Back to cited text no. 31
    
32.
Peer, C.A., 1938, Jour. of Med. Soc. of New Jersey, 35, 601.  Back to cited text no. 32
    
33.
Pfeffer, R.L., 1943, Arch. Ophthal., 30, 718.  Back to cited text no. 33
    
34.
Portman, A.E., 1900, Jour. All India Med. Assoc. 37, 978.  Back to cited text no. 34
    
35.
Prince, J.H., 1946, Ocular Prosthesis, 1st ed. pp 1­23, 46-47. E. and S. Livingstone, Edinburgh.   Back to cited text no. 35
    
36.
Ruedemnn, A.D., 1947, Arch. Ophthal., 38, 724.  Back to cited text no. 36
    
37.
Sherman, A.E., 1952, Amer. J. Ophthal., 35 89.  Back to cited text no. 37
    
38.
Smith, B., 1942, Arch. Ophthal., 28, 484.  Back to cited text no. 38
    
39.
Smith, B., Ober, M. & Leone, C.R. Jr., 1967, Amer. J. Ophthal., 64, 1088.  Back to cited text no. 39
    
40.
Smith, B., Leone, C.R. Jr. & Beyer, C.K., 1971, Proc. XXI Int. Congr. Ophthal. Mexico, 1970, pt-2, p 1474.  Back to cited text no. 40
    
41.
Souders, B.F., 1945, Quoted by Sherman, A.E., 1952.  Back to cited text no. 41
    
42.
Soll, D.B., 1971, Amer. J. Ophthal., 71, 763.   Back to cited text no. 42
    
43.
Soll, D.B., 1971, Arch. Ophthal., 85, 188.   Back to cited text no. 43
    
44.
Soll, D.B., 1972, Arch. Ophthal., 87, 196.  Back to cited text no. 44
    
45.
Spratt, C.N., 1913, Quated by Sherman, A.E., 1952.  Back to cited text no. 45
    
46.
Spivey, B.E., Allen, L. & Burns, C.A., 1969, Amer. J. Ophthal., 67, 171.  Back to cited text no. 46
    
47.
Speath. E., 1925, Quoted by Sherman, A.E,, 1952.   Back to cited text no. 47
    
48.
Struble, G.C., 1945, Quoted by Sherman, A.E., 1952.  Back to cited text no. 48
    
49.
Suker, G.E., 1903, Ann. Ophthal., 12, 51.  Back to cited text no. 49
    
50.
Sugar, H.S., & Forestner, H.J., 1946, Amer. J. Ophthal., 29, 993.  Back to cited text no. 50
    
51.
Taiara, C. & Smith, B., 1973, Brit. J. Ophthal., 57,741.  Back to cited text no. 51
    
52.
Vannas, S., 1946, Acta. Ophthal., 24, 225.   Back to cited text no. 52
    
53.
Vannas, S., 1958, Acta. Ophthal., 36, 444.  Back to cited text no. 53
    
54.
Weidler, W.B., 1912, Quoted by Sherman, A.E., 1952.  Back to cited text no. 54
    
55.
Wheeler, J.M., 1907, Quoted by Sherman, A.E., 1952.  Back to cited text no. 55
    
56.
Wheeler, J.M., 1921, Amer. J. Ophthal., 4, 481.  Back to cited text no. 56
    
57.
Wheeler, J.M., 1934, Quoted by Sherman, A.E., 1952.  Back to cited text no. 57
    
58.
Wheeler, J.M., 1936, Quoted by Sherman, A.E,, 1952.  Back to cited text no. 58
    
59.
Witter, G.L., 1945, Quoted by Sherman, A.E., 1952.  Back to cited text no. 59
    


    Figures

  [Figure - 1], [Figure - 2], [Figure - 3], [Figure - 4], [Figure - 5], [Figure - 6], [Figure - 7], [Figure - 8], [Figure - 9], [Figure - 10], [Figure - 11], [Figure - 12], [Figure - 13]
 
 
    Tables

  [Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5], [Table - 6], [Table - 7], [Table - 8], [Table - 9]



 

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