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a 48-year - old woman with a positive brca1 gene mutation was referred with a pelvic mass .
ca-125 was > 4,000 and a ct scan confirmed the presence of large bilateral ovarian tumours .
she underwent debulking surgery , and histology revealed completely resected stage 3b high - grade endometrioid ovarian carcinoma .
she was well , with a performance status of 0 and no medical history of note .
she was prescribed the regime of weekly paclitaxel 80 mg / m ( total dose 150 mg ) with concurrent 3-weekly carboplatin auc 6 ( total dose 740 mg ) . during the first cycle of paclitaxel
, she suffered an immediate allergic reaction ; therefore , subsequently her regime was switched to single - agent carboplatin at the previously calculated dose .
she received 2 cycles without incident , but her third cycle was delayed by 1 week owing to thrombocytopaenia ( platelet count 77  10/l ) , and her fourth was delayed by a further week due to neutropaenia ( neutrophil count 0.9  10/l ) . at review
prior to her fourth cycle , she mentioned an incidental finding of a blot haemorrhage at a routine optometrist visit , which was asymptomatic .
diabetic screening was performed at this stage in view of a strong family history , but was negative .
five days after her fifth cycle of carboplatin , she awoke with new - onset blurred vision in her left eye .
a ct scan of the head and orbits was performed which showed no evidence of metastases or raised intracranial pressure .
an autoimmune screen was performed which did not reveal any explanation for her visual symptoms .
fundus fluorescein angiography showed bilateral intense late disc leakage with no evidence of vasculitis ( fig .
2 ) . in view of her low platelet count and no clinically evident disc oedema in the right eye ,
the diagnosis was felt to be that of carboplatin - induced unilateral disc oedema . at this point ,
her chemotherapy was stopped in view of a radiological and biochemical remission and her visual symptoms were monitored .
her symptoms did not improve with steroids , however , and the dose was gradually tapered down .
five months after the initial review , she has developed left optic disc atrophy with 6/18 visual acuity , while the right eye remains asymptomatic .
its cytotoxicity results from alkylation of nucleic acids , which causes cross linking and double - strand breaks in dna .
the resulting fragmentation of dna and failure of dna replication and rna transcription lead to cell death .
the most frequently reported side effect of carboplatin is bone marrow suppression , causing anaemia , thrombocytopaenia and neutropaenia .
the british national formulary reports that it is generally far better tolerated than the related platinum - based chemotherapeutic agent cisplatin , with a much lower incidence of nonhaematological toxicity .
platinum - derived chemotherapeutic agents are known to have neurotoxic side effects , but these most commonly take the form of peripheral neuropathy and ototoxicity .
ophthalmic toxicity is rare but has been described , particularly in relation to cisplatin . in 2006 ,
a major review of the ocular side effects of systemic chemotherapy reported a range of visual problems related to both high - dose and cumulative - dose intravenous cisplatin therapy .
these ranged from blurred vision and papilloedema , reported as single cases and found to be reversible , to transient cortical blindness and macular pigmentary changes .
intracarotid cisplatin administration was also implicated in cases of severe ocular toxicity , particularly ipsilateral retrobulbar neuritis .
carboplatin has rarely been implicated as a causative agent in visual disturbance and optic nerve toxicity . in 1992 , 2 cases of sudden bilateral visual loss were described in women being treated with carboplatin for ovarian carcinoma .
they were both receiving high - dose intravenous carboplatin ( auc 12 , total doses 720 and 900 mg , respectively ) , and had impaired renal function ( glomerular filtration rate 45 and 50 ml / min , respectively ) .
the postulated mechanism was neurotoxicity from the agent crossing the blood - brain barrier in the context of poor renal excretion and high dose .
a further report , in 1993 , suggested an association between intravenous carboplatin and both maculopathy and optic neuropathy .
one patient was found to have bilateral maculopathy after 5 cycles of treatment , whilst the other suffered permanent visual disturbance which did not respond to steroids , leaving her with bilateral optic neuropathy and a coexistent right - sided maculopathy .
the report recommended the discontinuation of treatment in patients complaining of visual disturbance . in 2009 , fischer et al .   described a case of bilateral papilloedema in the context of treatment for stage 3c ovarian carcinoma with carboplatin ( auc 5 , total dose not given )
there was a loss of visual acuity in both eyes with visual field defects more prominent on the left side , along with a left - sided relative afferent pupillary defect .
intracranial pressure was normal and autoantibodies negative , leading the authors to suspect a diagnosis of carboplatin - induced papilloedema . in that case ,
the patient 's vision gradually improved over the course of 2 years , although there were residual signs of bilateral optic nerve atrophy , which was worse on the left side .
no cases of unilateral papilloedema associated with intravenous carboplatin treatment were found in the literature .
the review of ocular complications of chemotherapy in 2006 concluded that cases of optic neuropathy , cortical blindness , sore eyes , blurred vision , choroidoretinitis and optic neuritis associated with carboplatin administration were rare , and reversible .
we present a patient with normal renal function who was treated with standard - dose carboplatin , which produced irreversible unilateral papilloedema with resultant persistent visual disturbance .
fundus fluorescein angiography indicated right eye disc oedema and leakage , although these remained clinically nonevident .
this case , along with those described in 1992   and 2009 , suggests that ocular toxicity , including papilloedema , may be a rare side effect of carboplatin treatment that can result in permanent visual damage .
any visual signs or symptoms therefore need to be taken seriously , and chemotherapy should be stopped until there has been a full ophthalmological review .
a 48-year - old woman with a positive brca1 gene mutation was diagnosed with stage 3b high - grade ovarian endometrioid carcinoma . 
 she was treated with adjuvant carboplatin at a dose of 740 mg ( auc 6 ) in 3-weekly cycles . 
 five days after her fifth cycle of carboplatin , she awoke with new - onset blurred vision in her left eye . 
 an ophthalmology review showed left - sided disc oedema with normal optic nerve function tests and 6/24 visual acuity . 
 a ct scan of the head and orbits was performed which showed no evidence of metastasis or raised intracranial pressure . 
 an autoimmune screen was performed which did not reveal any explanation for her visual symptoms . 
 fundus fluorescein angiography showed bilateral intense late disc leakage with no evidence of vasculitis . 
 her chemotherapy was stopped in view of a radiological and biochemical remission and her visual symptoms were monitored . 
 she was also started on a tapering dose of prednisolone 40 mg daily . 
 five months after the initial review , she has developed left optic disc atrophy with 6/18 visual acuity , while the right eye remains asymptomatic . 
 the diagnosis was felt to be that of carboplatin - induced unilateral disc oedema , a very rare side effect of this chemotherapy .