The risk of cataractogenesis after gamma knife radiosurgery: a nationwide population based case-control study

Abstract

BackgroundMedical radiation is considered a factor responsible for cataractogenesis. However, the incidence of this ophthalmologic complication resulting from gamma knife radiosurgery (GKRS) has not yet been reported. The present study aimed to determine the risk of cataractogenesis associated with radiation exposure from GKRS.MethodsThis study used information from a random sample of one million persons enrolled in the nationally representative Taiwan National Health Insurance Research Database. The GK group consisted of patients who underwent GKRS between 2000 and 2009. The non-GK group was composed of subjects who had never undergone GKRS, but who were matched with the case group for time of enrollment, age, sex, history of coronary artery disease, hypertension, and diabetes.ResultsThere were 277 patients in the GK group and 2770 matched subjects in the non-GK group. The GK group had a higher overall incidence of cataracts (10.11% vs. 7.26%; crude hazard ratio [cHR], 1.59; 95% CI, 1.07–2.36; adjusted hazard ratio [aHR], 1.25; 95% CI, 0.82–1.90) than the non-GK group. Patients who had undergone computed tomography and/or cerebral angiography (CT/angio) studies had a higher risk of developing cataracts than those who did not (10.82% vs. 6.64%; cHR, 1.74; 95% CI, 1.31–2.30; aHR, 1.65; 95% CI, 1.22–2.23). The age group between 30 and 50 years had the highest risk of cataractogenesis in both the GK and CT/angio groups (cHR, 3.50; 95% CI, 1.58–7.72; aHR, 2.43; 95% CI, 1.02–5.81; cHR, 2.96; 95% CI, 1.47–5.99; aHR, 2.27; 95% CI, 1.05–4.93, respectively).ConclusionsRadiation exposure due to GKRS and CT/angio study may be independently associated with increased risk of cataractogenesis. We suggest routine dosimetry measurement of eye lens and proper protection for patients with benign lesions during GKRS. Regular follow-up imaging studies should avoid the use of CT/angio, and particular care should be taken in the 30–50-year-old age group, due to their significantly increased risk of cataract formation.

Gamma Knife Radiosurgery for Indirect Dural Carotid–Cavernous Fistula: Long-Term Ophthalmological Outcome

“…However, in some studies, radiation dosage as low as 0.5 Gy still has a detrimental effect on cataracts development [ 46 , 47 ]. Therefore, radiation exposure during gamma knife treatment or cerebral angiography carries a higher risk for cataractogenesis matched to the control [ 48 ]. In this study, the lens dose was far less than 0.5 Gy, which is believed to be the threshold for cataract development.…”

Haemorrhage rates of ruptured and unruptured brain arteriovenous malformation after radiosurgery: a nationwide population-based cohort study

“…According to the statistics of the Taiwanese NHI programme, approximately 97.11% of Taiwanese citizen (2002: 21 , 869, 478 of 22, 520, 776) are enrolled in the NHI. 9 According to the regulations of the NHI, patients receive a certificate of ‘catastrophic illness’ when first diagnosed with cerebral AVMs. Within the certificate’s validity period, patients are not required to pay any copayments for outpatient or inpatient care.…”

“…The details of this population-based database have been described previously. 9 Diagnoses were coded with the International Codes of Disease ninth Edition Clinical Modification (ICD-9-CM).…”