British Journal of Neurosurgery, December 2014; 28(6): 793–795 © 2014 The Neurosurgical Foundation ISSN: 0268-8697 print / ISSN 1360-046X online DOI: 10.3109/02688697.2014.913774
SHORT REPORT
Reversible acute bilateral blindness resulting from a frontal brain tumor: A case report Koji Hayashi, Mitsutoshi Nakada, Katsuyoshi Miyashita, Yutaka Hayashi & Jun-ichiro Hamada Department of Neurosurgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
The patient underwent emergent tumour resection via a transcortical approach, during which the tumour was completely resected. Pathological findings for the tumour were consistent with anaplastic oligodendroglioma. The patient underwent radiotherapy, 60 Gy (2 Gy/day) extended locally, and concomitant temozolomide therapy (75 mg/m2/day). On the first postoperative day, right-sided blindness was still present, whereas left acuity had improved to hand perception. Visual acuity gradually recovered on both sides, accompanied by an improvement in the optic nerve sheath (ONS) diameter on T2-weighted coronal MRI (Fig. 2). Fortunately, the patient went on to completely recover visual acuity (right, 1.2; left, 1.2) with a normal fundus 2 months after surgery. Likewise, the visual fields in the both sides were disturbed at Day 9 but were improved at Day 77 after surgery.
Abstract We experienced an unusual case of a 15-year-old girl who suffered acute bilateral blindness caused by a frontal lobe tumour. She underwent emergent operation, after which her vision recovered. This case emphasizes that a brain mass can cause sudden onset blindness and an emergency intervention might save the patient’s sight. Keywords: blindness; brain tumour; papilledema
Introduction Visual dysfunction is caused by space occupying lesions (SOLs) either directly (through the compression of the optic pathway or visual cortex) or indirectly (as a result of papilledema caused by intracranial pressure [ICP] elevation). This visual dysfunction progresses gradually and is irreversible after a certain point, especially in cases involving a brain tumor. Herein, we report a rare case of reversible acute onset bilateral blindness caused by a frontal lobe tumour.
Discussion To the best of our knowledge, this is the first case of reversible acute bilateral blindness due to a frontal brain tumour in which the recovery of visual acuity corresponded to the changing MRI findings. The ONS diameters on the T2-weighted coronal MRI scan clearly reflected the process of visual acuity recovery and findings of the fundus examination (Fig. 2). Papilledema results from orthograde axoplasmic flow stasis at the optic nerve head leading to edema of the nerve. Continued papilledema leads to an irreversible loss of axons and eventual optic atrophy. The time course for development of papilledema and subsequent vision loss is long if the ICP rises only slowly, especially in the case of brain tumours. However, once the chronic papilledema has damaged the optic nerve, visual acuity cannot be recovered, even if the ICP is subsequently normalized by removal of the SOL. The only similar report to this one is that of a patient with sub-acute onset of unilateral blindness due to a temporal lobe tumour. In that case, there was no postoperative recovery of visual function.1 Thus, the case we report here, involving reversible
Case report A 15-year-old previously healthy girl presented with a 1-month history of intermittent headache. This was followed by the sudden onset of complete bilateral blindness, at which point she was admitted to our hospital. Physical examination revealed that both of her pupils were dilated (8 mm/ 8 mm). Direct and indirect light reflexes were diminished in both eyes, and the fundus scope showed bilateral papilledema in the eye grounds. Computed tomography (CT) and magnetic resonance imaging (MRI) imaging demonstrated a huge enhanced mass with calcification and a large cyst in the right frontal lobe (Fig. 1A–C). The optic nerves on both sides showed hyper intensity on T2-weighted fluid attenuated inversion recovery (FLAIR) MRI (Fig. 1D). The abnormalities of signal intensity in other optic pathway structures including occipital lobes were not seen in MRI.
Correspondence: Mitsutoshi Nakada, Department of Neurosurgery, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa 920-8641, Japan. Tel: ⫹ 81-76-265-2384. Fax: ⫹ 81-76-234-4262. E-mail: [email protected] Received for publication 19 Augsut 2013; accepted 6 April 2014
793
794
K. Hayashi et al.
Fig. 1. (A) A preoperative enhanced CT scan revealed an enhanced lesion with calcification and a cyst located in the right frontal lobe. (B)–(C) Preoperative axial (B) and sagittal (C) enhanced T1-weighted MRI images reveal multiple cysts circumscribed by the enhanced wall. (D) A T2FLAIR image shows hyperintensity of the optic nerves on both sides.
acute blindness caused by a brain tumour, would seem to be extremely rare. A number of possible mechanisms could explain the abrupt visual loss in this case. One of these is the immediate compression of the optic nerve by cerebrospinal fluid (CSF) within the ONS. Previous reports demonstrated that the structure of the subarachnoid cistern around the ONS is different from that of other subarachnoid cisterns, as it forms a Cul-de-Sac structure with no exit for CSF. This characteristic
Day
Coronal MRI
structure may cause compartment syndrome, explaining the acute increase of pressure on the optic nerves. Indeed, MRI revealed the presence of a large volume of CSF surrounding the optic nerve in our case. Kimberly et al. suggested that an ONS diameter more than 5 mm corresponds to an ICP greater than 20 cm H2O.2 In addition, the FLAIR MRI image in this case showed an edematous change in both branches of the optic nerve. These findings suggest that the pressure on the optic nerve was extremely high at the time of admission.
Optic nerve sheath diameter (mm) Right
Left
1
6.4
6.4
29
5.2
5.4
76
4.8
4.7
Fig. 2. T2-weighted coronal MRI after surgery revealing the diameter of the optic nerve sheath. On the first preoperative day, this was 6.4 mm for both branches and decreased gradually over the following 11 weeks.
Bilateral blindness due to frontal brain tumor 795 A second possible mechanism involves the release of neurotoxic agents, such as lipocalin-type prostaglandin D synthase (L-PGDS), which would very rapidly damage the optic nerve.3 L-PGDS is produced by meningoepithelial cells, and previous studies have shown that the concentration of L-PGDS is higher in the ONS than in the spinal CSF. Compartment syndrome at the site of the optic nerve might reduce the turnover of CSF, leading to the acute accumulation of L-PGDS and hence neurotoxicity. A third possible mechanism leading to a sudden loss of vision is the transient ischemia of the optic nerves. Ischemic optic neuropathy might be caused by occlusion or stenosis of the vessels supplying the optic nerve due to the high ICP. There was no objective evidence of ischemic optic neuropathy in this case. However, the sudden onset of blindness and reversible visual dysfunction might be explained by this mechanism. In many previous cases where visual loss was due to acute or chronic papilledema, visual function was only
incompletely rescued.1 However, visual loss was fully reversible in the case reported here, possibly due to early resection of the brain tumour. In conclusion, acute bilateral visual loss can be caused by a brain tumour, the early removal of which might preserve visual function. Declaration of interest: The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.
References 1. Seth A , Short S, Bremner F. Sub-acute blindness in a patient with a temporal lobe astrocytoma. BMJ Case Rep 2009;1:1513. 2. Kimberly HH, Shah S, Marill K, Noble V. Correlation of optic nerve sheath diameter with direct measurement of intracranial pressure. Acad Emerg Med 2008;15:201–4. 3. Killer HE, Jaggi GP, Flammer J, et al. Cerebrospinal fluid dynamics between the intracranial and the subarachnoid space of the optic nerve. Is it always bidirectional? Brain 2007;130:514–20.
Copyright of British Journal of Neurosurgery is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
SHORT REPORT
Reversible acute bilateral blindness resulting from a frontal brain tumor: A case report Koji Hayashi, Mitsutoshi Nakada, Katsuyoshi Miyashita, Yutaka Hayashi & Jun-ichiro Hamada Department of Neurosurgery, Graduate School of Medical Science, Kanazawa University, Kanazawa, Japan
The patient underwent emergent tumour resection via a transcortical approach, during which the tumour was completely resected. Pathological findings for the tumour were consistent with anaplastic oligodendroglioma. The patient underwent radiotherapy, 60 Gy (2 Gy/day) extended locally, and concomitant temozolomide therapy (75 mg/m2/day). On the first postoperative day, right-sided blindness was still present, whereas left acuity had improved to hand perception. Visual acuity gradually recovered on both sides, accompanied by an improvement in the optic nerve sheath (ONS) diameter on T2-weighted coronal MRI (Fig. 2). Fortunately, the patient went on to completely recover visual acuity (right, 1.2; left, 1.2) with a normal fundus 2 months after surgery. Likewise, the visual fields in the both sides were disturbed at Day 9 but were improved at Day 77 after surgery.
Abstract We experienced an unusual case of a 15-year-old girl who suffered acute bilateral blindness caused by a frontal lobe tumour. She underwent emergent operation, after which her vision recovered. This case emphasizes that a brain mass can cause sudden onset blindness and an emergency intervention might save the patient’s sight. Keywords: blindness; brain tumour; papilledema
Introduction Visual dysfunction is caused by space occupying lesions (SOLs) either directly (through the compression of the optic pathway or visual cortex) or indirectly (as a result of papilledema caused by intracranial pressure [ICP] elevation). This visual dysfunction progresses gradually and is irreversible after a certain point, especially in cases involving a brain tumor. Herein, we report a rare case of reversible acute onset bilateral blindness caused by a frontal lobe tumour.
Discussion To the best of our knowledge, this is the first case of reversible acute bilateral blindness due to a frontal brain tumour in which the recovery of visual acuity corresponded to the changing MRI findings. The ONS diameters on the T2-weighted coronal MRI scan clearly reflected the process of visual acuity recovery and findings of the fundus examination (Fig. 2). Papilledema results from orthograde axoplasmic flow stasis at the optic nerve head leading to edema of the nerve. Continued papilledema leads to an irreversible loss of axons and eventual optic atrophy. The time course for development of papilledema and subsequent vision loss is long if the ICP rises only slowly, especially in the case of brain tumours. However, once the chronic papilledema has damaged the optic nerve, visual acuity cannot be recovered, even if the ICP is subsequently normalized by removal of the SOL. The only similar report to this one is that of a patient with sub-acute onset of unilateral blindness due to a temporal lobe tumour. In that case, there was no postoperative recovery of visual function.1 Thus, the case we report here, involving reversible
Case report A 15-year-old previously healthy girl presented with a 1-month history of intermittent headache. This was followed by the sudden onset of complete bilateral blindness, at which point she was admitted to our hospital. Physical examination revealed that both of her pupils were dilated (8 mm/ 8 mm). Direct and indirect light reflexes were diminished in both eyes, and the fundus scope showed bilateral papilledema in the eye grounds. Computed tomography (CT) and magnetic resonance imaging (MRI) imaging demonstrated a huge enhanced mass with calcification and a large cyst in the right frontal lobe (Fig. 1A–C). The optic nerves on both sides showed hyper intensity on T2-weighted fluid attenuated inversion recovery (FLAIR) MRI (Fig. 1D). The abnormalities of signal intensity in other optic pathway structures including occipital lobes were not seen in MRI.
Correspondence: Mitsutoshi Nakada, Department of Neurosurgery, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa 920-8641, Japan. Tel: ⫹ 81-76-265-2384. Fax: ⫹ 81-76-234-4262. E-mail: [email protected] Received for publication 19 Augsut 2013; accepted 6 April 2014
793
794
K. Hayashi et al.
Fig. 1. (A) A preoperative enhanced CT scan revealed an enhanced lesion with calcification and a cyst located in the right frontal lobe. (B)–(C) Preoperative axial (B) and sagittal (C) enhanced T1-weighted MRI images reveal multiple cysts circumscribed by the enhanced wall. (D) A T2FLAIR image shows hyperintensity of the optic nerves on both sides.
acute blindness caused by a brain tumour, would seem to be extremely rare. A number of possible mechanisms could explain the abrupt visual loss in this case. One of these is the immediate compression of the optic nerve by cerebrospinal fluid (CSF) within the ONS. Previous reports demonstrated that the structure of the subarachnoid cistern around the ONS is different from that of other subarachnoid cisterns, as it forms a Cul-de-Sac structure with no exit for CSF. This characteristic
Day
Coronal MRI
structure may cause compartment syndrome, explaining the acute increase of pressure on the optic nerves. Indeed, MRI revealed the presence of a large volume of CSF surrounding the optic nerve in our case. Kimberly et al. suggested that an ONS diameter more than 5 mm corresponds to an ICP greater than 20 cm H2O.2 In addition, the FLAIR MRI image in this case showed an edematous change in both branches of the optic nerve. These findings suggest that the pressure on the optic nerve was extremely high at the time of admission.
Optic nerve sheath diameter (mm) Right
Left
1
6.4
6.4
29
5.2
5.4
76
4.8
4.7
Fig. 2. T2-weighted coronal MRI after surgery revealing the diameter of the optic nerve sheath. On the first preoperative day, this was 6.4 mm for both branches and decreased gradually over the following 11 weeks.
Bilateral blindness due to frontal brain tumor 795 A second possible mechanism involves the release of neurotoxic agents, such as lipocalin-type prostaglandin D synthase (L-PGDS), which would very rapidly damage the optic nerve.3 L-PGDS is produced by meningoepithelial cells, and previous studies have shown that the concentration of L-PGDS is higher in the ONS than in the spinal CSF. Compartment syndrome at the site of the optic nerve might reduce the turnover of CSF, leading to the acute accumulation of L-PGDS and hence neurotoxicity. A third possible mechanism leading to a sudden loss of vision is the transient ischemia of the optic nerves. Ischemic optic neuropathy might be caused by occlusion or stenosis of the vessels supplying the optic nerve due to the high ICP. There was no objective evidence of ischemic optic neuropathy in this case. However, the sudden onset of blindness and reversible visual dysfunction might be explained by this mechanism. In many previous cases where visual loss was due to acute or chronic papilledema, visual function was only
incompletely rescued.1 However, visual loss was fully reversible in the case reported here, possibly due to early resection of the brain tumour. In conclusion, acute bilateral visual loss can be caused by a brain tumour, the early removal of which might preserve visual function. Declaration of interest: The authors report no declarations of interest. The authors alone are responsible for the content and writing of the paper.
References 1. Seth A , Short S, Bremner F. Sub-acute blindness in a patient with a temporal lobe astrocytoma. BMJ Case Rep 2009;1:1513. 2. Kimberly HH, Shah S, Marill K, Noble V. Correlation of optic nerve sheath diameter with direct measurement of intracranial pressure. Acad Emerg Med 2008;15:201–4. 3. Killer HE, Jaggi GP, Flammer J, et al. Cerebrospinal fluid dynamics between the intracranial and the subarachnoid space of the optic nerve. Is it always bidirectional? Brain 2007;130:514–20.
Copyright of British Journal of Neurosurgery is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
