Biomedical subjects
Publications and source records attributed to C C Kok-van Alphen.
The results of analyses of 1218 consecutive corneal transplants performed in a single centre reveal that the most important prognostic factors for corneal allograft survival are recipient corneal vascularisation, graft diameter, HLA-A and B matching especially for high risk patients, organ culture storage of donor corneas prior to transplantation and donor age.
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The number of contact lenses worn has increased steadily in the last decades. The number and types of complications have increased in approximately the same degree. New, hitherto unknown, complications are continually described. The complications are classified according to the factors which cause them: complications of mechanical origin; complications due to metabolic disorders; allergic reactions; exogenous infections; disorders of tear production. The lesions found in the cornea and the conjunctiva are described. The complications caused by hard lenses are usually noticed earlier by the patient than those due to soft lenses, because the lesions caused by hard lenses are usually painful, whereas those due to soft lenses are not.
A retrospective review of 288 penetrating keratoplasties (PKP) for herpes simplex keratitis demonstrated a 60.4% survival rate of clear grafts at 3 years. A highly significant difference in corneal graft survival in severely vascularized corneas (57.1% at 3 years) versus non- or slightly vascularized corneas (82.8% at 3 years) was observed (P = 0.009). Prospectively HLA-A and -B matched grafts in vascularized corneas revealed a significantly improved graft survival when compared to unmatched grafts (P = 0.035). Corneal graft survival in eyes grafted 'à chaud' was not significantly below the graft survival of vascularized corneas with a clinically non-active herpetic corneal disease. Recurrence of herpes simplex in the graft was observed in an earlier postoperative period in HLA-A and -B matched grafts (P = 0.0004).
Re-examination of the fate of 136 corneal grafts for bullous keratopathy (secondary endothelial decompensation) revealed a decreased, but not significant, graft survival of those grafts compared to the total of 572 grafts in patients with a diagnosis other than bullous keratopathy, as well as a decreased graft survival when compared to the survival of the grafts for Fuchs dystrophy (primary endothelial decompensation). A statistically significant decreased graft survival (P = 0.015) was observed when corneal grafts performed in pseudophakic eyes with secondary endothelial decompensation were compared to those performed in aphakic eyes with secondary endothelial decompensation. An immunological explanation for this difference was not detected. The influence of an intraocular lens on corneal corneal graft survival was analyzed. Indications for removing or retaining the intraocular lens at the time of graft surgery are reported.
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Over the years we have noticed on more than one occasion a connection between rejection of a corneal graft and emotional stress. We considered this at first to be a coincidence. However, we have now seen 11 patients in whom an acute rejection occurred just after emotional stress. There appears to be a clear relationship between psychological stress and rejection.
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Automutilation of the cornea occurs more frequently than is generally supposed. The patient, particularly at his first visit, certainly will not reveal the cause of the cornea lesion. In two University Eye Clinics 19 patients were seen in whom the diagnosis of automutilation of the cornea could be made. It is important for the ophthalmologist to bear the possibility of automutilation in mind. In 6 of our patients corneal grafts were performed. All these grafts failed because of further automutilation. Corneal transplantation is certainly not indicated; these operations were performed because the patient's true condition had not been spotted in time. Better forms of treatment are tarsorrhaphy or the application of closely occluding bandages. In this way fair results were obtained in 2 cases. It is wrong to force the patient to a confrontation (i.e. to tell him that automutilation is suspected). Confrontation can lead to more severe mental disorders. In all cases psychiatric treatment is absolutely essential. The ophthalmological prognosis for this condition is poor and psychiatric help is quite often refused.
In connection with a number of ophthalmological patients in whom automutilation was seen, the background to this behaviour is considered. It is usually seen in patients with a borderline personality. Automutilants differ from simulants. In practice, it is important to avoid confrontation and to look out for 'splitting'. Psychiatric treatment is seldom successful.
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Different influences on corneal survival were studied in 539 grafts. The follow-up period ranged from 3 months to 4 1/2 years. The degree of vascularization of the host cornea, previous graft failures and the diameter of the graft could be demonstrated to influence the graft survival significantly. A significant influence of sex differences between donors and recipients was found. A female donor results in a better graft survival in female recipient as compared to male recipients. No significant influence on graft survival was found of pregnancies and blood transfusions. Age of the donor, storage methods and time lapse between death and transplantation did not influence the graft survival either.
The effect of prospective HLA-A and -B matching on corneal graft survival was studied in 159 Dutch recipients. The follow-up period ranges from 3 months to 4 1/2 years. In the same period 380 grafts were performed at random. The influence of HLA-A and -B matching on graft survival in all vascularized cases (n = 137) was significant (P = 0.046). If the non-immunological failures are excluded the effect of HLA-A and -B matchings becomes more pronounced (P = 0.027). The influence of HLA-A and -B matching on the graft survival of only the first grafts in vascularized corneas was more significant (p = 0.028). Finally a significant influence of HLA-A and -B matching was also found in repeated grafts in vascularized corneas (P = 0.037).
As introduction to a light- and electron-microscopial examination of rejected human corneal grafts a summary is given of the clinical signs of rejection. It is extremely important to recognize these signs in time and to initiate the correct therapy. Most failures in corneal transplantation are due to rejection. Rejection reactions are often not recognized early enough. The differential diagnosis is difficult because so many factors can trigger off a rejection. As the diagnosis is so often missed it is a good thing to consider the clinical picture of graft rejection once more. Maumenee: 'most ophthalmologists do not recognize the signs of early graft failure and usually do not refer the patient back for therapy until considerable oedema has developed from endothelial destruction' (1962). In the cases with a good prognosis the rejection percentage is plus or minus 12%; in vascularized corneas and complicated corneal transplantations as high as 75% (Polack, 1977).
Six rejected human corneal grafts out of a group of 40 'bad-risk corneas' were systematically studied by light and electron microscopy. Remarkable fine structural similarities in this sample of corneas were observed. Granulocytes, lymphocytes and plasma cells are common in all rejected grafts. Furthermore, the epithelial and endothelial linings and the stroma reveal the characteristic alterations. The observations indicate an immunological reaction of the recipient to the donor corneas.
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A severe kerato-iritis of the right eye of a 36-year-old healthy man constituted a diagnostic and therapeutic problem. More than seven months after the onset of his complaints a cornea transplantation was carried out because a large abscess had developed in the stroma of the cornea and perforation was feared. Amoebae, belonging to the free-living genus Acanthamoeba, were found in the excised corneal disc. Similar infections have been described earlier in the USA, in England and in Germany. The case described here is the first well documented one in the Netherlands. The case history and identification of the amoeba are described. Data from the literature on epidemiology, pathogenicity and treatment are discussed.