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Chiasmatic cavernoma haemorrhage: To treat or not to treat? Concerning a clinical case
Neurochirurgie 61 (2015) 343–346
Disponible en ligne sur
ScienceDirect www.sciencedirect.com
Clinical case
Chiasmatic cavernoma haemorrhage: To treat or not to treat? Concerning a clinical case Cavernome hémorragique du chiasma optique : traiter ou ne pas traiter ? À propos d’un cas clinique G. Marnat a,∗ , E. Gimbert b , J. Berge a , M.-B. Rougier c , S. Molinier a , V. Dousset a,d,e a
Department of Interventional and Diagnostic Neuroradiology, Bordeaux University Hospital, 26, rue Mondenard, 33000 Bordeaux, France Department of Neurosurgery A, Bordeaux University Hospital, 33000 Bordeaux, France c Department of Ophthalmology, Bordeaux University Hospital, 33000 Bordeaux, France d Bordeaux University, Institut de Bio-Imagerie de Bordeaux UMS 3428, 33000 Bordeaux, France e Inserm, U862, Physiopathologie de la plasticité neuronale, 33000 Bordeaux, France b
a r t i c l e
i n f o
Article history: Received 25 February 2015 Received in revised form 15 April 2015 Accepted 23 May 2015 Available online 4 August 2015 Keywords: Optic chiasm Cavernoma MRI Cranial nerve
a b s t r a c t We present the case of a 43-year-old man with acute visual loss due to an optic chiasm cavernoma. Our clinical and imaging findings quickly led us to this diagnosis. As a clinical improvement spontaneously occurred soon after the initial diagnosis, we decided not to perform any surgical treatment. The visual evolution was satisfactory and, to date after a 36-months follow-up, no clinical worsening has been reported. We present this clinical case regarding our approach, primarily a close follow-up, as well as a review of the literature. © 2015 Elsevier Masson SAS. All rights reserved.
r é s u m é Mots clés : Chiasma optique Cavernome IRM Nerfs crâniens
Nous présentons le cas d’un homme de 43 ans présentant une baisse d’acuité visuelle brutale due à une hémorragie d’un cavernome chiasmatique. Puisqu’une amélioration spontanée significative survint rapidement après le saignement, nous décidions de ne pas traiter chirurgicalement la lésion. L’évolution visuelle fut satisfaisante et, à ce jour, après 36 mois de suivi, aucune aggravation ou récidive n’est survenue. Nous présentons ce cas pour l’approche clinique que nous avons choisi, c’est-à-dire une surveillance rapprochée, ainsi qu’une revue de la littérature. © 2015 Elsevier Masson SAS. Tous droits réservés.
1. Case report A 43-year-old man with no particular past medical history was admitted to the Emergency Department of Pellegrin University Hospital, Bordeaux, complaining of acute visual impairment and headaches. An early initial ophthalmologic examination revealed
∗ Corresponding author. E-mail address: gaultier [email protected] (G. Marnat). http://dx.doi.org/10.1016/j.neuchi.2015.05.005 0028-3770/© 2015 Elsevier Masson SAS. All rights reserved.
a severe, acute loss of visual acuity, with a score of 3/10. It also showed a left homonymous lateral hemianopia. Due to the acute symptomatology, a cerebral CT-scan was performed. It showed no evident subarachnoid haemorrhage or other obvious recent intra-parenchymal bleeding, nor any sign of intracranial hypertension. However, a spontaneous suprasellar roundish hyper-density was detected (Fig. 1A). A brain MRI was immediately carried out in order to characterize the lesion. It showed a suprasellar mass, heterogeneous on the T1 and T2 weighted sequences with a surrounding hyposignal in T2* weighted sequence, without enhancement after gadolinium
344
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
Fig. 1. Imaging explorations of the lesion. Initial CT-scan revealed a spontaneously hyper-dense suprasellar mass (A) without enhancement and a visible vascular abnormality. MRI at 3T (GE Medical Systems) showed a heterogeneous lesion with mixed hyper- and hyposignals T1 and T2 (C and D) producing a typical “pop-corn aspect” and a hyposignal T2*. Precise exploration with coronal and axial T2 sequences allowed highlighting a lesion centred on the optic chiasm and fusing anteriorly into the left optic nerve and posteriorly to the left optic pathway. The FLAIR weighted imaging revealed a perimesenchephalic suprasellar hyperintense signal (B) likely explained by a suffering related to the recent bleeding (causing a local mass effect and inflammation) and probably associated with a minimal subarachnoid haemorrhage. After 15 months (E and F), the MRI showed a significant decrease in volume of the haematoma with persistent signal abnormalities due to the cavernoma. Bilan radiologique de la lésion. Le scanner cérébral initial révélait une hyperdensité spontanée suprasellaire (A) sans rehaussement ni anomalie vasculaire. Une IRM à 3 Tesla montrait une masse hétérogène avec des signaux mixtes hypo et hyper en T1 et T2 (C et D) créant un aspect « pop-corn » évocateur et un hyposignal T2* marqué. Des explorations précisent en séquences coronales et axiales T2 démontraient une lésion centrée sur le chiasma, fusant en avant vers le nerf optique gauche et en arrière vers les voies optiques. La séquence FLAIR révélait un hypersignal périmésencéphalique suprasellaire (B) vraisemblablement expliqué par une souffrance liée au saignement récent (entraînant un effet de masse locale et une inflammation réactionnelle) ainsi qu’une minime hémorragie sous-arachnoïdienne. Après 15 mois (E et F), l’IRM montrait une diminution significative du volume de l’hématome chiasmatique avec des anomalies de signal persistantes en rapport avec le cavernome sous-jacent.
injection (Fig. 1B to G). These findings led to a diagnosis of a recent haematoma (occurring between 5 and 8 days previously according to the MRI signal). At the time, our alternative hypotheses were spontaneously thrombosed aneurysm, meningioma, optic glioma, optic neuritis, pial or chiasmatic cavernoma, craniopharyngioma or metastatic haemorrhagic suprasellar lesion. The results of the conventional angiogram were normal, thereby eliminating a high flow vascular malformation. A few days later, the patient’s loss of vision had improved. His visual score reached 8/10 with a remaining homonymous lateral hemianopia. As this partial recovery occurred spontaneously and
soon after the onset, we made the decision to carry out an active and close monitoring of the patient by means of regular ophthalmologic examinations and MRI controls. After 2 months, MRI showed a heterogeneous mass developed at the expanse of the optic chiasm. It appeared in mixed hyper- and hyposignal in T1 and T2 weighted sequences with a typical “pop-corn” aspect associated with a marked roundish hyposignal T2*. There was still no enhancement and the size had slightly decreased. Based on these elements, we ruled out any several aetiologies such as glioma, craniopharyngioma, meningioma and metastasis. The MRI presentation was moreover evocative of a chiasmatic
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
cavernoma. Due to the patient’s improvement in vision and MRI findings, a strategy of close and on-going follow-up was maintained and no surgical resection was performed. We also carried out an additional medullar MR exploration which showed no other cavernoma localization and excluding the diagnosis of cavernomatosis. No genetic research of hereditary cavernomatosis was performed considering the sole attempt and the absence of any hereditary disease. After a 15-months follow-up, the patient recovered almost completely from his visual deficiency. The visual acuity was 10/10 with a remaining isolated infero-nasal quadrantanopia of the left eye, without attempt of the right visual field, and with no significant consequence for the patient’s everyday life (Fig. 2). Long-term MRI findings reinforced the diagnosis of optic chiasm cavernoma: it demonstrated a chiasm lesion of mixed signal in T1 and T2 weighted sequences, with a strong hyposignal T2*, the persisting absence of enhancement and a significant reduction in size due to the progressive resorption of the haemorrhagic component. The patient still continues to be monitored by a neurosurgeon, an ophthalmologist and a neuroradiologist. To date, after 36 months from the initial symptomatology, there has been no clinical worsening.
345
2. Discussion Cavernous malformations, also called cavernomas or cavernous angiomas, correspond to low flow vascular lesions composed of multiple sinusoid-like interspersed capillaries containing no functional parenchyma. Therefore, because of their disorganized architecture, these small abnormal vessels are very sensitive to thrombosis and bleedings. The malformation may be isolated, multiple (up to 19% according to literature) [1] or hereditary (6–50% of all cases) [2]. This lesion has a specific presentation in imaging. MRI is the recommended way to explore and recognize cavernomas. They appear as roundish lesions with heterogeneous signal (“pop-corn like”) in T1 and T2 sequences [3]. This heterogeneous mixed signal is especially observable when performing T2 FIESTA weighted MR with millimetric slices. A strong hyposignal in T2* imaging is a significant finding: this aspect is due to an accumulation of the haemoglobin degradation products which are secondary to repetitive micro-haemorrhages and thrombosis [4]. Most cavernomas do not present enhancement after gadolinium injection. In approximately 9% of cases, the cavernoma is coupled with a developmental venous anomaly. The CT-Scan aspect is unspecific and often reveals calcifications. Cavernous angiomas are angiographically occult.
Fig. 2. Visual fields at onset (A and B) and evolution after 15 months (C and D). Initially, we note a severe bitemporal hemianopsy with a satisfying evolution after 15 months follow-up, with a normal vision in the right eye and a residual defect in the temporal field of the left eye. Champs visuels initiaux (A et B) et après 15 mois (C et D). Initialement, on notait une hémianopsie bitemporale sévère. L’évolution à 15 mois était satisfaisante avec une vision normale à l’œil droit et un défect résiduel dans le champ temporal gauche.
346
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
As described in the literature [1], depending on the location where they appear, cavernomas range from the very common to the rarest: cerebral hemisphere (66%), brainstem and spinal cord (18%), basal ganglia and thalamus (8,2%), cerebellum (6%), corpus callosum (1%) and insula (0.2%). As such, cranial nerve lesions are very uncommon. These types of lesions have previously been reported for the optic nerve (II), oculomotor (III), trochlear (IV), trigeminal nerve (V), facial/vestibulo cochlear complex (VII–VIII) and hypoglossal (XII) [5,6]. Approximately 50 cases of optic pathway cavernomas have been reported to date [7,8]. Clinical presentation is frequently characterized as an optochiasmal apoplexy corresponding to sudden visual deficiency and often with an acute and retro-orbital headache. Transient visual disorders are sometimes reported in the preceding weeks. In a few patients, a chronic evolution occurs with a progressive visual loss or transient episodes. The differential diagnosis of an optic nerve cavernoma includes an optic glioma, optic neuritis, arteriovenous malformation, intracranial aneurysm, metastasis and craniopharyngioma. These alternatives can be ruled out based on clinical presentation and evolution, the patient’s previous medical history and imaging explorations (cerebral DSA, MRI and CT-scan). Considering our decision not to perform microsurgery, we did not, in fact, have any histological proof of a cavernoma. Nevertheless, the clinical presentation, the imaging aspect and the clinical and radiological evolution entirely ruled out the differential diagnosis and reinforced our hypothesis. In a retrospective review of the published cases, Liu et al. [7] reported that more than 90% of cavernomas were treated surgically with gross total resection in 60% of cases, subtotal in 6% and biopsy with or without resection of the haemorrhage in 29%. The outcome was globally favourable with an improvement in vision resulting in 75% of the published cases. In cases of surgical treatment (whether gross total, subtotal resection or decompression), the symptomatic evolution was satisfactory in 74% of cases. Two patients experienced a worsening of vision impairment after surgical removal, corresponding to 4% of those treated for optic chiasm cavernomas. Only two of the patients presented in this study benefited from any medical treatment alone: one experienced visual improvement and the second suffered from a worsening of their symptoms. Localised radiotherapy has also been proposed and reported but without significant effectiveness. The natural history of this type of localisation is no, in fact, known due to the rareness of this diagnosis and the surgical treatment performed in most reported cases. In the cerebral parenchyma, haemorrhagic risk has been estimated to be 0.7% per lesion-year [1]. The increasing of a bleeding risk after the first episode of a haemorrhage has not been demonstrated with certainty, although it is suspected. The only proven haemorrhagic risk factor appears to be the female gender [2]. Indeed age, size or cavernoma location do not for the time being appear associated with an increased risk of bleeding [1,2]. In the case of our patient, the decision to avoid a surgical intervention in the first instance was prompted by the speed of the spontaneous visual recovery. Taking into account the potential risk of worsening secondary to surgery of the optic chiasm, and because of the substantial visual improvement, which occurred spontaneously after a two-day period, we considered aggressive surgical treatment to have an unfavourable benefit–risk ratio. In literature, we found that there was at least a 4% risk of complication associated with surgery [6,7]. The estimated risk of rebleeding,
although not precisely known, appeared lower. Furthermore, we thought that the haemorrhagic risk was reduced, likely due to the probable destruction of the cavernoma by the acute hematoma itself and the presumed natural history. In addition, being precisely and repeatedly informed, the patient was extremely hesitant about the procedure. Nevertheless, this in cases of worsening headaches and/or visual efficiency during the follow-up, we would have performed the surgical resection in emergency with no reduction in the likelihood for the patient’s recovery. 3. Conclusion Our case is of clinical interest in that it provides evidence based on observation of the natural history of a vascular malformation of this type and in this location. Since reported cases deal primarily with surgical interventions regarding optic chiasm cavernomas, spontaneous evolution is still not well understood. Consequently, and in view of the positive outcome which we observed with the non-interventionist treatment, we would suggest that it is important to justify the risk of complication associated with any surgical procedure. Our patient experienced a rapid, spontaneous improvement in his visual acuity, followed by a progressive subtotal recovery of the visual field deficiency. After nearly a one-and-a-half-year follow-up, no clinical worsening occurred and consecutive visual field exploration showed regular improvements. Close monitoring with surgery to be performed in an emergency, (i.e. in cases of functional and/or clinical deterioration) appears to be the preferred approach in order to manage this rare cavernoma location, providing there is an optimal balance between benefits and risks. Disclosure of interest The authors declare that they have no conflicts of interest concerning this article. Acknowledgements The authors thank Mrs. Cindy Chambaud for her precious assistance. This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. References [1] Gross B, Lin N, Du R, Day AL. The natural history of intracranial cavernous malformations. Neurosurg Focus 2011;30(6):E24. [2] Washington CW, McCoy KE, Zipfel GJ. Update on the natural history of cavernous malformations and factors predicting aggressive clinical presentation. Neurosurg Focus 2010;29(3):E7. [3] Ginat D, Meyers S. Intracranial lesions with high signal intensity on T1-weighted MR images: differential diagnosis. Radiographics 2012;32:499–516. [4] Wurm G, Fellner F. Implementation of T2*-weighted MR for multimodal image guidance in cerebral cavernomas. Neuroimage 2004;22(2):841–6. [5] Deshmukh VR, Albuquerque FC, Zabramski JM, Spetzler RF. Surgical management of cavernous malformations involving the cranial nerves. Neurosurgery 2003;53(2):352–7. [6] Manjila S, Moon K, Weiner M, Cohen ML, Leigh RJ, Megerian C, et al. Cavernous malformation of the trochlear nerve: case report and review of the literature on cranial nerve cavernomas. Neurosurgery 2011;69(1):E230–8 [discussion E238]. [7] Liu JK, Lu Y, Raslan AM, Gultekin SH, Delashaw JB. Cavernous malformations of the optic pathway and hypothalamus: analysis of 65 cases in the literature. Neurosurg Focus 2010;29(3):E17. [8] Crocker M, Desouza R, King A, Path FRC, Connor S, Thomas N, et al. Cavernous hemangioma of the optic chiasm: a surgical review. Skull Base 2008;18(3):201–12.
Disponible en ligne sur
ScienceDirect www.sciencedirect.com
Clinical case
Chiasmatic cavernoma haemorrhage: To treat or not to treat? Concerning a clinical case Cavernome hémorragique du chiasma optique : traiter ou ne pas traiter ? À propos d’un cas clinique G. Marnat a,∗ , E. Gimbert b , J. Berge a , M.-B. Rougier c , S. Molinier a , V. Dousset a,d,e a
Department of Interventional and Diagnostic Neuroradiology, Bordeaux University Hospital, 26, rue Mondenard, 33000 Bordeaux, France Department of Neurosurgery A, Bordeaux University Hospital, 33000 Bordeaux, France c Department of Ophthalmology, Bordeaux University Hospital, 33000 Bordeaux, France d Bordeaux University, Institut de Bio-Imagerie de Bordeaux UMS 3428, 33000 Bordeaux, France e Inserm, U862, Physiopathologie de la plasticité neuronale, 33000 Bordeaux, France b
a r t i c l e
i n f o
Article history: Received 25 February 2015 Received in revised form 15 April 2015 Accepted 23 May 2015 Available online 4 August 2015 Keywords: Optic chiasm Cavernoma MRI Cranial nerve
a b s t r a c t We present the case of a 43-year-old man with acute visual loss due to an optic chiasm cavernoma. Our clinical and imaging findings quickly led us to this diagnosis. As a clinical improvement spontaneously occurred soon after the initial diagnosis, we decided not to perform any surgical treatment. The visual evolution was satisfactory and, to date after a 36-months follow-up, no clinical worsening has been reported. We present this clinical case regarding our approach, primarily a close follow-up, as well as a review of the literature. © 2015 Elsevier Masson SAS. All rights reserved.
r é s u m é Mots clés : Chiasma optique Cavernome IRM Nerfs crâniens
Nous présentons le cas d’un homme de 43 ans présentant une baisse d’acuité visuelle brutale due à une hémorragie d’un cavernome chiasmatique. Puisqu’une amélioration spontanée significative survint rapidement après le saignement, nous décidions de ne pas traiter chirurgicalement la lésion. L’évolution visuelle fut satisfaisante et, à ce jour, après 36 mois de suivi, aucune aggravation ou récidive n’est survenue. Nous présentons ce cas pour l’approche clinique que nous avons choisi, c’est-à-dire une surveillance rapprochée, ainsi qu’une revue de la littérature. © 2015 Elsevier Masson SAS. Tous droits réservés.
1. Case report A 43-year-old man with no particular past medical history was admitted to the Emergency Department of Pellegrin University Hospital, Bordeaux, complaining of acute visual impairment and headaches. An early initial ophthalmologic examination revealed
∗ Corresponding author. E-mail address: gaultier [email protected] (G. Marnat). http://dx.doi.org/10.1016/j.neuchi.2015.05.005 0028-3770/© 2015 Elsevier Masson SAS. All rights reserved.
a severe, acute loss of visual acuity, with a score of 3/10. It also showed a left homonymous lateral hemianopia. Due to the acute symptomatology, a cerebral CT-scan was performed. It showed no evident subarachnoid haemorrhage or other obvious recent intra-parenchymal bleeding, nor any sign of intracranial hypertension. However, a spontaneous suprasellar roundish hyper-density was detected (Fig. 1A). A brain MRI was immediately carried out in order to characterize the lesion. It showed a suprasellar mass, heterogeneous on the T1 and T2 weighted sequences with a surrounding hyposignal in T2* weighted sequence, without enhancement after gadolinium
344
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
Fig. 1. Imaging explorations of the lesion. Initial CT-scan revealed a spontaneously hyper-dense suprasellar mass (A) without enhancement and a visible vascular abnormality. MRI at 3T (GE Medical Systems) showed a heterogeneous lesion with mixed hyper- and hyposignals T1 and T2 (C and D) producing a typical “pop-corn aspect” and a hyposignal T2*. Precise exploration with coronal and axial T2 sequences allowed highlighting a lesion centred on the optic chiasm and fusing anteriorly into the left optic nerve and posteriorly to the left optic pathway. The FLAIR weighted imaging revealed a perimesenchephalic suprasellar hyperintense signal (B) likely explained by a suffering related to the recent bleeding (causing a local mass effect and inflammation) and probably associated with a minimal subarachnoid haemorrhage. After 15 months (E and F), the MRI showed a significant decrease in volume of the haematoma with persistent signal abnormalities due to the cavernoma. Bilan radiologique de la lésion. Le scanner cérébral initial révélait une hyperdensité spontanée suprasellaire (A) sans rehaussement ni anomalie vasculaire. Une IRM à 3 Tesla montrait une masse hétérogène avec des signaux mixtes hypo et hyper en T1 et T2 (C et D) créant un aspect « pop-corn » évocateur et un hyposignal T2* marqué. Des explorations précisent en séquences coronales et axiales T2 démontraient une lésion centrée sur le chiasma, fusant en avant vers le nerf optique gauche et en arrière vers les voies optiques. La séquence FLAIR révélait un hypersignal périmésencéphalique suprasellaire (B) vraisemblablement expliqué par une souffrance liée au saignement récent (entraînant un effet de masse locale et une inflammation réactionnelle) ainsi qu’une minime hémorragie sous-arachnoïdienne. Après 15 mois (E et F), l’IRM montrait une diminution significative du volume de l’hématome chiasmatique avec des anomalies de signal persistantes en rapport avec le cavernome sous-jacent.
injection (Fig. 1B to G). These findings led to a diagnosis of a recent haematoma (occurring between 5 and 8 days previously according to the MRI signal). At the time, our alternative hypotheses were spontaneously thrombosed aneurysm, meningioma, optic glioma, optic neuritis, pial or chiasmatic cavernoma, craniopharyngioma or metastatic haemorrhagic suprasellar lesion. The results of the conventional angiogram were normal, thereby eliminating a high flow vascular malformation. A few days later, the patient’s loss of vision had improved. His visual score reached 8/10 with a remaining homonymous lateral hemianopia. As this partial recovery occurred spontaneously and
soon after the onset, we made the decision to carry out an active and close monitoring of the patient by means of regular ophthalmologic examinations and MRI controls. After 2 months, MRI showed a heterogeneous mass developed at the expanse of the optic chiasm. It appeared in mixed hyper- and hyposignal in T1 and T2 weighted sequences with a typical “pop-corn” aspect associated with a marked roundish hyposignal T2*. There was still no enhancement and the size had slightly decreased. Based on these elements, we ruled out any several aetiologies such as glioma, craniopharyngioma, meningioma and metastasis. The MRI presentation was moreover evocative of a chiasmatic
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
cavernoma. Due to the patient’s improvement in vision and MRI findings, a strategy of close and on-going follow-up was maintained and no surgical resection was performed. We also carried out an additional medullar MR exploration which showed no other cavernoma localization and excluding the diagnosis of cavernomatosis. No genetic research of hereditary cavernomatosis was performed considering the sole attempt and the absence of any hereditary disease. After a 15-months follow-up, the patient recovered almost completely from his visual deficiency. The visual acuity was 10/10 with a remaining isolated infero-nasal quadrantanopia of the left eye, without attempt of the right visual field, and with no significant consequence for the patient’s everyday life (Fig. 2). Long-term MRI findings reinforced the diagnosis of optic chiasm cavernoma: it demonstrated a chiasm lesion of mixed signal in T1 and T2 weighted sequences, with a strong hyposignal T2*, the persisting absence of enhancement and a significant reduction in size due to the progressive resorption of the haemorrhagic component. The patient still continues to be monitored by a neurosurgeon, an ophthalmologist and a neuroradiologist. To date, after 36 months from the initial symptomatology, there has been no clinical worsening.
345
2. Discussion Cavernous malformations, also called cavernomas or cavernous angiomas, correspond to low flow vascular lesions composed of multiple sinusoid-like interspersed capillaries containing no functional parenchyma. Therefore, because of their disorganized architecture, these small abnormal vessels are very sensitive to thrombosis and bleedings. The malformation may be isolated, multiple (up to 19% according to literature) [1] or hereditary (6–50% of all cases) [2]. This lesion has a specific presentation in imaging. MRI is the recommended way to explore and recognize cavernomas. They appear as roundish lesions with heterogeneous signal (“pop-corn like”) in T1 and T2 sequences [3]. This heterogeneous mixed signal is especially observable when performing T2 FIESTA weighted MR with millimetric slices. A strong hyposignal in T2* imaging is a significant finding: this aspect is due to an accumulation of the haemoglobin degradation products which are secondary to repetitive micro-haemorrhages and thrombosis [4]. Most cavernomas do not present enhancement after gadolinium injection. In approximately 9% of cases, the cavernoma is coupled with a developmental venous anomaly. The CT-Scan aspect is unspecific and often reveals calcifications. Cavernous angiomas are angiographically occult.
Fig. 2. Visual fields at onset (A and B) and evolution after 15 months (C and D). Initially, we note a severe bitemporal hemianopsy with a satisfying evolution after 15 months follow-up, with a normal vision in the right eye and a residual defect in the temporal field of the left eye. Champs visuels initiaux (A et B) et après 15 mois (C et D). Initialement, on notait une hémianopsie bitemporale sévère. L’évolution à 15 mois était satisfaisante avec une vision normale à l’œil droit et un défect résiduel dans le champ temporal gauche.
346
G. Marnat et al. / Neurochirurgie 61 (2015) 343–346
As described in the literature [1], depending on the location where they appear, cavernomas range from the very common to the rarest: cerebral hemisphere (66%), brainstem and spinal cord (18%), basal ganglia and thalamus (8,2%), cerebellum (6%), corpus callosum (1%) and insula (0.2%). As such, cranial nerve lesions are very uncommon. These types of lesions have previously been reported for the optic nerve (II), oculomotor (III), trochlear (IV), trigeminal nerve (V), facial/vestibulo cochlear complex (VII–VIII) and hypoglossal (XII) [5,6]. Approximately 50 cases of optic pathway cavernomas have been reported to date [7,8]. Clinical presentation is frequently characterized as an optochiasmal apoplexy corresponding to sudden visual deficiency and often with an acute and retro-orbital headache. Transient visual disorders are sometimes reported in the preceding weeks. In a few patients, a chronic evolution occurs with a progressive visual loss or transient episodes. The differential diagnosis of an optic nerve cavernoma includes an optic glioma, optic neuritis, arteriovenous malformation, intracranial aneurysm, metastasis and craniopharyngioma. These alternatives can be ruled out based on clinical presentation and evolution, the patient’s previous medical history and imaging explorations (cerebral DSA, MRI and CT-scan). Considering our decision not to perform microsurgery, we did not, in fact, have any histological proof of a cavernoma. Nevertheless, the clinical presentation, the imaging aspect and the clinical and radiological evolution entirely ruled out the differential diagnosis and reinforced our hypothesis. In a retrospective review of the published cases, Liu et al. [7] reported that more than 90% of cavernomas were treated surgically with gross total resection in 60% of cases, subtotal in 6% and biopsy with or without resection of the haemorrhage in 29%. The outcome was globally favourable with an improvement in vision resulting in 75% of the published cases. In cases of surgical treatment (whether gross total, subtotal resection or decompression), the symptomatic evolution was satisfactory in 74% of cases. Two patients experienced a worsening of vision impairment after surgical removal, corresponding to 4% of those treated for optic chiasm cavernomas. Only two of the patients presented in this study benefited from any medical treatment alone: one experienced visual improvement and the second suffered from a worsening of their symptoms. Localised radiotherapy has also been proposed and reported but without significant effectiveness. The natural history of this type of localisation is no, in fact, known due to the rareness of this diagnosis and the surgical treatment performed in most reported cases. In the cerebral parenchyma, haemorrhagic risk has been estimated to be 0.7% per lesion-year [1]. The increasing of a bleeding risk after the first episode of a haemorrhage has not been demonstrated with certainty, although it is suspected. The only proven haemorrhagic risk factor appears to be the female gender [2]. Indeed age, size or cavernoma location do not for the time being appear associated with an increased risk of bleeding [1,2]. In the case of our patient, the decision to avoid a surgical intervention in the first instance was prompted by the speed of the spontaneous visual recovery. Taking into account the potential risk of worsening secondary to surgery of the optic chiasm, and because of the substantial visual improvement, which occurred spontaneously after a two-day period, we considered aggressive surgical treatment to have an unfavourable benefit–risk ratio. In literature, we found that there was at least a 4% risk of complication associated with surgery [6,7]. The estimated risk of rebleeding,
although not precisely known, appeared lower. Furthermore, we thought that the haemorrhagic risk was reduced, likely due to the probable destruction of the cavernoma by the acute hematoma itself and the presumed natural history. In addition, being precisely and repeatedly informed, the patient was extremely hesitant about the procedure. Nevertheless, this in cases of worsening headaches and/or visual efficiency during the follow-up, we would have performed the surgical resection in emergency with no reduction in the likelihood for the patient’s recovery. 3. Conclusion Our case is of clinical interest in that it provides evidence based on observation of the natural history of a vascular malformation of this type and in this location. Since reported cases deal primarily with surgical interventions regarding optic chiasm cavernomas, spontaneous evolution is still not well understood. Consequently, and in view of the positive outcome which we observed with the non-interventionist treatment, we would suggest that it is important to justify the risk of complication associated with any surgical procedure. Our patient experienced a rapid, spontaneous improvement in his visual acuity, followed by a progressive subtotal recovery of the visual field deficiency. After nearly a one-and-a-half-year follow-up, no clinical worsening occurred and consecutive visual field exploration showed regular improvements. Close monitoring with surgery to be performed in an emergency, (i.e. in cases of functional and/or clinical deterioration) appears to be the preferred approach in order to manage this rare cavernoma location, providing there is an optimal balance between benefits and risks. Disclosure of interest The authors declare that they have no conflicts of interest concerning this article. Acknowledgements The authors thank Mrs. Cindy Chambaud for her precious assistance. This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. References [1] Gross B, Lin N, Du R, Day AL. The natural history of intracranial cavernous malformations. Neurosurg Focus 2011;30(6):E24. [2] Washington CW, McCoy KE, Zipfel GJ. Update on the natural history of cavernous malformations and factors predicting aggressive clinical presentation. Neurosurg Focus 2010;29(3):E7. [3] Ginat D, Meyers S. Intracranial lesions with high signal intensity on T1-weighted MR images: differential diagnosis. Radiographics 2012;32:499–516. [4] Wurm G, Fellner F. Implementation of T2*-weighted MR for multimodal image guidance in cerebral cavernomas. Neuroimage 2004;22(2):841–6. [5] Deshmukh VR, Albuquerque FC, Zabramski JM, Spetzler RF. Surgical management of cavernous malformations involving the cranial nerves. Neurosurgery 2003;53(2):352–7. [6] Manjila S, Moon K, Weiner M, Cohen ML, Leigh RJ, Megerian C, et al. Cavernous malformation of the trochlear nerve: case report and review of the literature on cranial nerve cavernomas. Neurosurgery 2011;69(1):E230–8 [discussion E238]. [7] Liu JK, Lu Y, Raslan AM, Gultekin SH, Delashaw JB. Cavernous malformations of the optic pathway and hypothalamus: analysis of 65 cases in the literature. Neurosurg Focus 2010;29(3):E17. [8] Crocker M, Desouza R, King A, Path FRC, Connor S, Thomas N, et al. Cavernous hemangioma of the optic chiasm: a surgical review. Skull Base 2008;18(3):201–12.