Journal of the Neurological Sciences 353 (2015) 183–184
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Letter to the Editor A case of papilloedema associated with Chiari I malformation Keywords: Chiari I malformation Papilloedema Idiopathic intracranial hypertension
The patient underwent posterior fossa decompression through C1 laminectomy and duroplasty. At 2-weeks follow-up, there was a remarkable clinical improvement with complete recovery of headache, visual blurring and papilloedema, at last follow-up, two months after surgery, the patient was free of symptoms.
2. Discussion
Dear Editor, Chiari I malformation (CIM) is a rare congenital malformation of the hindbrain manifesting as herniation of the cerebellar tonsils below the foramen magnum [1]. It usually becomes symptomatic in late childhood or early adulthood. Patients may complain of headache or symptoms related to cranial nerve compression, cerebellar dysfunction, myelopathy and syringomyelia [1]. Ocular nerve involvement is an uncommon feature of CIM and can present with oculomotor nerve palsy and accommodation abnormalities [1]. Papilloedema has been rarely reported though can be a severe presenting symptom [1–6] mimicking idiopathic intracranial hypertension (IIH) and making the diagnosis challenging. We report a case of CIM associated with papilloedema successfully treated with suboccipital decompression.
1. Case report A 40-year-old woman was referred for a 3-week history of visual blurring and persistent headache. Her medical history included migraine with aura and a surgery for congenital pulmonary valve stenosis. Her body mass index (BMI) was normal (23.7). Ophthalmic examination showed normal visual acuity (20/20 bilaterally) and colour vision (10/10 bilaterally) at the Hardy–Rand–Rittler (HRR) pseudoisochromatic plates. Pupils were bilaterally 6 mm and normally reactive to light and accommodation. Motility, ocular pressure and slit-lamp examinations were normal. Fundoscopic evaluation revealed bilateral optic disc oedema (Fig. 1). Visual field testing using automated perimetry showed an enlarged blind spot. Optical coherence tomography (OCT) indicated bilateral optic nerve fibre layer elevation with global averages of 134 and 139 μm at the right and left eye, respectively. Cerebral tomography (CT) was normal. Lumbar puncture performed in lateral decubitus showed an opening pressure of 7 mmHg (normal value 8–10 mmHg) with a normal concentration of glucose, protein and cells in the cerebrospinal fluid (CSF). Brain magnetic resonance imaging (MRI) of the patient did not show intracranial lesions or ventricular enlargement while disclosed Chiari I malformation characterized by a 7-mm tonsillar herniation below the foramen magnum (Fig. 1). Angio-MR ruled out venous sinus thrombosis and spinal cord examination was unremarkable.
http://dx.doi.org/10.1016/j.jns.2015.04.016 0022-510X/© 2015 Elsevier B.V. All rights reserved.
The differential diagnosis of papilloedema includes intracranial space-occupying lesions, cerebral venous thrombosis and meningeal lesions. In our patient, all these causes were ruled out by brain MRI and CSF examination. Another condition associated with papilloedema is intracranial idiopathic hypertension (IIH), which was ruled out based on normal opening pressure at lumbar puncture [7]. Intriguingly, brain MRI disclosed a previously unknown CIM. Papilloedema is a rare but known manifestation of CIM, previously reported in 2% of patients with symptomatic CIM [1] along with further anecdotal observations [2–5]. The mechanisms underlying papilloedema in CIM may be an intermittent cranio-spinal CSF pressure unbalance. In CIM patients, newly formed CSF may be displaced from the compressed subarachnoid spaces of the posterior cranial fossa into available spaces within the supratentorial and spinal compartments, thus altering the normal damping effect of the open system able to mitigate venous volume and pressure changes physiologically occurring during the respiration, cardiac pulse, Valsalva maneuver and change in posture. Obstruction of the CSF flow at the level of foramen magnum may delay the balance of pressure between cranial and spinal compartments, leading to increased intracranial pressure and papilloedema. However, the evidence of papiloledema in such a small proportion of CIM patients suggests that other predisposing factors play a role. In our patient, the hypothesis of an isolated supratentorial increased intracranial pressure is supported by the finding of normal opening pressure on lumbar puncture. There are few literature data regarding the treatment of CIM-related papilloedema. In a retrospective case series of 4 patients [3], acetazolamide was inefficacy,whereas surgical decompression of the posterior fossa allowed the recovery of the clinical picture. The same surgical approach was described as beneficial in single case reports [2,5,6] although two patients [5,6] developed bilateral optic nerve atrophy and one complained of a residual visual field defect [5]. Surgical treatment is not always indicated in CIM, however papilledema is a dangerous condition that, if untreated, can led to visual loss, for this reason we decided for surgery. In our case, suboccipital decompression led to a complete recovery of signs and symptoms, even if the follow-up period was limited and a longer follow-up observation is necessary to evaluate the full efficacy of this approach. The differential diagnosis with IIH may be challenging in clinical practice and has therapeutic implications. IIH may require repeated CSF drainage or permanent shunting that are contraindicated in CIM as they may precipitate acute hindbrain herniation. In cases of CIM misdiagnosed wit IHH, lumbar puncture led to severe neurological and visual deterioration [2–4]. Our observation emphasizes that CIM
184
Letter to the Editor
Fig. 1. Neuroradiological and funduscopic picture of the patient. 1A Sagittal T1-weighted brain MRI showing Chiari I malformation. 1B–1C Fundus photographs showing bilateral papilloedema.
should be considered in any patient with unexplained papilloedema and focused brain MRI examination should be performed. Posterior fossa decompression may be considered the first-line treatment.
Giuseppe Lauria Neuroalgology and Headache Unit, National Neurological Institute, C. Besta, Via Celoria 11, 20133 Milan, Italy
References
Vittorio Mantero Francesca Piamarta Neuroalgology and Headache Unit, National Neurological Institute, C. Besta, Via Celoria 11, 20133 Milan, Italy
[1] Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell M, Wolpert C, et al. Chiari I malfomation redefined: clinical and radiographic findings for 364 symptomatic patients. Neurosurgery 1999;44:1005–17. [2] Choudhari KA, Cooke C, Hong Tan M, Gray WJ. Papilloedema as the sole presenting feature of Chiari I malformation. Br J Neurosurg 2002;16:398–400. [3] Vaphiades MS, Eggenberger ER, Miller NR, Frohman L, Krisht A. Resolution of papilledema after neurosurgical decompression for primary Chiari I malformation. Am J Ophthalmol 2002;133:673–8. [4] Vrabec TR, Sergott RC, Savino PJ, Bosley TM. Intermittent obstructive hydrocephalus in the Arnold-Chiari malformation. Ann Neurol 1989;26:401–4. [5] Zhang JC, Bakir B, Lee A, Yalamanchili SS. Papilloedema due to Chiari I malformation. BMJ Case Rep 2011. http://dx.doi.org/10.1136/bcr.08.2011.4271. [6] Kurschel S, Maier R, Gellner V, Eder HG. Chiari I malformation and intra-cranial hypertension: a case-based review. Childs Nerv Syst 2007;23:901–5. [7] Dandy WE. Inracranial pressure without brain tumor: diagnosis and treatment. Ann Surg 1937;106:492–513.
Andrea Rigamonti Neurological Department, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy Corresponding author at: Department of Neurology, “Alessandro Manzoni” General Hospital, Via Dell'Eremo 9/11, 23900 Lecco, Italy. Tel.: +39 341 489805; fax: +39 341 489801. E-mail address: [email protected].
Michele Parolin Neurosurgery, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy Andrea Salmaggi Neurological Department, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy 21 February 2015
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Letter to the Editor A case of papilloedema associated with Chiari I malformation Keywords: Chiari I malformation Papilloedema Idiopathic intracranial hypertension
The patient underwent posterior fossa decompression through C1 laminectomy and duroplasty. At 2-weeks follow-up, there was a remarkable clinical improvement with complete recovery of headache, visual blurring and papilloedema, at last follow-up, two months after surgery, the patient was free of symptoms.
2. Discussion
Dear Editor, Chiari I malformation (CIM) is a rare congenital malformation of the hindbrain manifesting as herniation of the cerebellar tonsils below the foramen magnum [1]. It usually becomes symptomatic in late childhood or early adulthood. Patients may complain of headache or symptoms related to cranial nerve compression, cerebellar dysfunction, myelopathy and syringomyelia [1]. Ocular nerve involvement is an uncommon feature of CIM and can present with oculomotor nerve palsy and accommodation abnormalities [1]. Papilloedema has been rarely reported though can be a severe presenting symptom [1–6] mimicking idiopathic intracranial hypertension (IIH) and making the diagnosis challenging. We report a case of CIM associated with papilloedema successfully treated with suboccipital decompression.
1. Case report A 40-year-old woman was referred for a 3-week history of visual blurring and persistent headache. Her medical history included migraine with aura and a surgery for congenital pulmonary valve stenosis. Her body mass index (BMI) was normal (23.7). Ophthalmic examination showed normal visual acuity (20/20 bilaterally) and colour vision (10/10 bilaterally) at the Hardy–Rand–Rittler (HRR) pseudoisochromatic plates. Pupils were bilaterally 6 mm and normally reactive to light and accommodation. Motility, ocular pressure and slit-lamp examinations were normal. Fundoscopic evaluation revealed bilateral optic disc oedema (Fig. 1). Visual field testing using automated perimetry showed an enlarged blind spot. Optical coherence tomography (OCT) indicated bilateral optic nerve fibre layer elevation with global averages of 134 and 139 μm at the right and left eye, respectively. Cerebral tomography (CT) was normal. Lumbar puncture performed in lateral decubitus showed an opening pressure of 7 mmHg (normal value 8–10 mmHg) with a normal concentration of glucose, protein and cells in the cerebrospinal fluid (CSF). Brain magnetic resonance imaging (MRI) of the patient did not show intracranial lesions or ventricular enlargement while disclosed Chiari I malformation characterized by a 7-mm tonsillar herniation below the foramen magnum (Fig. 1). Angio-MR ruled out venous sinus thrombosis and spinal cord examination was unremarkable.
http://dx.doi.org/10.1016/j.jns.2015.04.016 0022-510X/© 2015 Elsevier B.V. All rights reserved.
The differential diagnosis of papilloedema includes intracranial space-occupying lesions, cerebral venous thrombosis and meningeal lesions. In our patient, all these causes were ruled out by brain MRI and CSF examination. Another condition associated with papilloedema is intracranial idiopathic hypertension (IIH), which was ruled out based on normal opening pressure at lumbar puncture [7]. Intriguingly, brain MRI disclosed a previously unknown CIM. Papilloedema is a rare but known manifestation of CIM, previously reported in 2% of patients with symptomatic CIM [1] along with further anecdotal observations [2–5]. The mechanisms underlying papilloedema in CIM may be an intermittent cranio-spinal CSF pressure unbalance. In CIM patients, newly formed CSF may be displaced from the compressed subarachnoid spaces of the posterior cranial fossa into available spaces within the supratentorial and spinal compartments, thus altering the normal damping effect of the open system able to mitigate venous volume and pressure changes physiologically occurring during the respiration, cardiac pulse, Valsalva maneuver and change in posture. Obstruction of the CSF flow at the level of foramen magnum may delay the balance of pressure between cranial and spinal compartments, leading to increased intracranial pressure and papilloedema. However, the evidence of papiloledema in such a small proportion of CIM patients suggests that other predisposing factors play a role. In our patient, the hypothesis of an isolated supratentorial increased intracranial pressure is supported by the finding of normal opening pressure on lumbar puncture. There are few literature data regarding the treatment of CIM-related papilloedema. In a retrospective case series of 4 patients [3], acetazolamide was inefficacy,whereas surgical decompression of the posterior fossa allowed the recovery of the clinical picture. The same surgical approach was described as beneficial in single case reports [2,5,6] although two patients [5,6] developed bilateral optic nerve atrophy and one complained of a residual visual field defect [5]. Surgical treatment is not always indicated in CIM, however papilledema is a dangerous condition that, if untreated, can led to visual loss, for this reason we decided for surgery. In our case, suboccipital decompression led to a complete recovery of signs and symptoms, even if the follow-up period was limited and a longer follow-up observation is necessary to evaluate the full efficacy of this approach. The differential diagnosis with IIH may be challenging in clinical practice and has therapeutic implications. IIH may require repeated CSF drainage or permanent shunting that are contraindicated in CIM as they may precipitate acute hindbrain herniation. In cases of CIM misdiagnosed wit IHH, lumbar puncture led to severe neurological and visual deterioration [2–4]. Our observation emphasizes that CIM
184
Letter to the Editor
Fig. 1. Neuroradiological and funduscopic picture of the patient. 1A Sagittal T1-weighted brain MRI showing Chiari I malformation. 1B–1C Fundus photographs showing bilateral papilloedema.
should be considered in any patient with unexplained papilloedema and focused brain MRI examination should be performed. Posterior fossa decompression may be considered the first-line treatment.
Giuseppe Lauria Neuroalgology and Headache Unit, National Neurological Institute, C. Besta, Via Celoria 11, 20133 Milan, Italy
References
Vittorio Mantero Francesca Piamarta Neuroalgology and Headache Unit, National Neurological Institute, C. Besta, Via Celoria 11, 20133 Milan, Italy
[1] Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell M, Wolpert C, et al. Chiari I malfomation redefined: clinical and radiographic findings for 364 symptomatic patients. Neurosurgery 1999;44:1005–17. [2] Choudhari KA, Cooke C, Hong Tan M, Gray WJ. Papilloedema as the sole presenting feature of Chiari I malformation. Br J Neurosurg 2002;16:398–400. [3] Vaphiades MS, Eggenberger ER, Miller NR, Frohman L, Krisht A. Resolution of papilledema after neurosurgical decompression for primary Chiari I malformation. Am J Ophthalmol 2002;133:673–8. [4] Vrabec TR, Sergott RC, Savino PJ, Bosley TM. Intermittent obstructive hydrocephalus in the Arnold-Chiari malformation. Ann Neurol 1989;26:401–4. [5] Zhang JC, Bakir B, Lee A, Yalamanchili SS. Papilloedema due to Chiari I malformation. BMJ Case Rep 2011. http://dx.doi.org/10.1136/bcr.08.2011.4271. [6] Kurschel S, Maier R, Gellner V, Eder HG. Chiari I malformation and intra-cranial hypertension: a case-based review. Childs Nerv Syst 2007;23:901–5. [7] Dandy WE. Inracranial pressure without brain tumor: diagnosis and treatment. Ann Surg 1937;106:492–513.
Andrea Rigamonti Neurological Department, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy Corresponding author at: Department of Neurology, “Alessandro Manzoni” General Hospital, Via Dell'Eremo 9/11, 23900 Lecco, Italy. Tel.: +39 341 489805; fax: +39 341 489801. E-mail address: [email protected].
Michele Parolin Neurosurgery, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy Andrea Salmaggi Neurological Department, A.O. Manzoni, Via Dell'Eremo 9/11, 23900 Lecco, Italy 21 February 2015
