[Downloaded free from http://www.neurologyindia.com on Thursday, May 15, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Letters to Editor
2. 3. 4. 5.
Ersahin Y, Mutluer S, Damirtas E. Intraosseous neurinoma of the parietal bone. Childs Nerv Syst 2000;16:181-3. Celli P, Cervoni L, Colonnese C. Intraosseous schwannoma of the vault of the skull. Neurosurg Rev 1998;21:158-60. Ito S, Mandai T, Ishida K, Deguchi H, Hata T, Irei I, et al. Intraosseous schwannoma of the mandible: A case report. Kawasaki Med J 2009;35:249-52. Ramina R, Mattei TA, Sória MG, da Silva EB Jr, Leal AG, Neto MC, et al. Surgical management of trigeminal schwannomas. Neurosurg Focus 2008;25:E6. Access this article online Quick Response Code:
Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.132447
Received: 19-02-2014 Review completed: 13-03-2014 Accepted: 06-04-2014
Absence status epilepsy: Report of a rare electro-clinical syndrome Sir, We report a patient with “absence status epilepsy” and discuss the features specific to this syndrome. A 49-year-old presented with an acute confusional state, which lasted for more than 24 hours. There was
no family history of seizures. From the age of 16, he started getting generalized tonic-clonic seizures (GTCS) at yearly intervals for 5 years, which subsequently became very infrequent. He was on 500 mg of sodium valproate. From the age of 20, he used to have episodes of confusion and unresponsiveness lasting for hours precipitated by sleep deprivation and emotional disturbances. He used to recover after a nap. These episodes became more frequent and prolonged, interfering with official work and necessitating multiple hospital admissions. There was no history of myoclonic jerks. At admission, he was confused. An urgent video-electroencephalography (EEG) was performed, which showed continuous runs of generalized spike-wave (SW) discharges at 3 Hz [Figure 1a]. He was partially responsive during these events and the discharges became discontinuous when aroused [Figure 1b]. Intravenous lorazepam 2 mg aborted the absence status [Figure 2a]. Subsequently he had intermittent runs of generalized SW discharges at 3 Hz lasting 10-20 seconds, which tapered-off over the next two hours when he recovered completely clinically and electrically. The inter-ictal record showed frontally dominant and generalized fast SW discharges [Figure 2b] suggestive of idiopathic generalized epilepsies (IGE). Hyperventilation and photic stimulation did not activate the discharges. Magnetic resonance imaging (MRI) of brain was normal and ring chromosome-20 was negative. He was put on 1 gm of sodium valproate and is event-free for the past six months. Absence status epilepticus (AS) is a prolonged and non-convulsive seizure occurring in various circumstances. International League Against Epilepsy
a
b Figure 1: EEG showing continuous runs of 3 Hz spike and wave discharges (a) with periods of discontinuity on asking questions (b)
224
Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
[Downloaded free from http://www.neurologyindia.com on Thursday, May 15, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Letters to Editor
a
b Figure 2: EEG following intravenous lorazepam showing disappearance of the status. (a) Interictal EEG showing the generalized discharges suggesting Idiopathic Generalized Epilepsy (b)
(ILAE) diagnostic scheme considers AS as a subtype of generalized status epilepticus.[1] Typical AS, occurs in the setting of all IGEs, especially in juvenile absence epilepsy (JAE), and atypical AS occurs in symptomatic generalized epilepsies. In 2008, Genton et al., described a new epilepsy syndrome in 11 patients with AS as their predominant or only seizure manifestation and so he proposed the name “absence status epilepsy”.[2] Herein, we describe a patient in whom the main seizure type is recurrent AS, infrequent GTCS, and no typical absences (TA). The onset of AS is after puberty and the prognosis is favorable on adequate treatment. Emotional disturbances, sleep deprivation and inadequate dose of sodium valproate were the triggering factors. The EEG findings as well as normal neurological and MRI findings supported IGE. Our patient is different from the well-known syndromes of IGE associated with AS, namely Juvenile myoclonic epilepsy (JME), JAE or IGE with phantom absences.[3,4] His electro-clinical features fit into the AS syndrome, described by Genton and colleagues.[2] Absence status epilepsy is described with onset in puberty or early adulthood. The predominant seizure type is recurrent AS. Unlike the other better known absence syndromes, TAs are extremely rare or absent. GTCS is infrequent. This syndrome lacks positive family history. There is no photoparoxysmal response, and activation to hyperventilation is rare. The interictal EEG shows normal background activity and generalized spike and wave, and polyspike and wave discharges of 2-4 Hz frequency. The seizure Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
control is generally excellent with adequate doses of sodium valproate. This atypical presentation of prolonged confusional state would make us think of complex partial status resulting in the use of inappropriate drugs. Also, inadequate dosage of drugs including that of sodium valproate could increase the incidence of AS and GTCS. Recognizing AS as a separate syndrome would thus help in earlier identification and appropriate and adequate treatment.
Rajesh Shankar Iyer, S. R. Nisha Department of Neurology, K. G. Hospital and Post Graduate Medical Institute, Coimbatore, Tamil Nadu, India E-mail: [email protected]
References 1.
2. 3. 4.
Engel J Jr. International League Against Epilepsy (ILAE). A proposed diagnostic scheme for people with epileptic seizures and with epilepsy: Report of the ILAE Task Force on Classification and Terminology. Epilepsia 2001;42:796-803. Genton P, Ferlazzo E, Thomas P. Absence status epilepsy: Delineation of a distinct idiopathic generalized epilepsy syndrome. Epilepsia 2008;49:642-9. Agathonikou A, Panayiotopoulos CP, Giannakodimos S, Koutroumanidis M. Typical absence status in adults: Diagnostic and syndromic considerations. Epilepsia 1998;39:1265-76. Panayiotopoulos CP, Koutroumanidis M, Giannakodimos S, Agathonikou A. Idiopathic generalized epilepsy in adults manifests by phantom absences, generalised tonic-clonic seizures, and frequent absences status. J Neurol Neurosurg Psychiatry 1997;63:622-7.
225
[Downloaded free from http://www.neurologyindia.com on Thursday, May 15, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Letters to Editor
Access this article online Quick Response Code:
Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.132448
Received: 08-01-2014 Review completed: 08-01-2014 Accepted: 06-04-2014
Modified French door laminoplasty using autologous spinous process as interlaminar spacer Sir, Laminoplasty is one surgical option to treat multilevel cervical spondylotic myelopathy, especially when associated with ossified posterior longitudinal ligament (OPLL) and spinal canal stenosis.[1] Posterior approaches to decompress multilevel cervical spinal cord compression include laminectomy, laminectomy with fusion, and laminoplasty. Laminectomy safely brings adequate decompression of the cervical spinal cord; nevertheless, it can have the adverse outcomes of epidural scar formation (post-laminectomy membrane) after cervical laminectomy and of post-laminectomy kyphosis secondary to iatrogenic destabilization of the cervical spine.[2] Laminoplasty allows the spinal cord and the neuro-foramen to be decompressed without directly removing anterior pathology. By preserving the dorsal elements of the spine, laminoplasty preserves spine stability and alignment and decreases the risk of post-laminectomy kyphosis and instability.[1] A 42-year-old male with insidious onset of neck pain radiating to both hands and weakness of both upper and lower limb for last eight month complained of progressive difficulty in walking with spasticity of lower limbs and became bedridden since last one month with a pre-op Nurick grade 5. He had atrophy of the small muscles of hand, spastic gait and 4/5 weakness of the muscles of upper limb and 3/5 over lower limb and grip weakness bilaterally. Deep tendon reflexes were exaggerated. The plantar reflexes were extensor bilaterally, and there were sustained clonus at the ankles. Magnetic resonance imaging (MRI) of the cervical spine and computed tomography (CT) scan demonstrated circumferential stenotic levels at C3-C4, C4-C5, and C6-C7 due to disc herniation and OPLL. Through posterior approach, following midline dissection 226
along the avascular subperiosteal plane, paraspinal muscles are retracted laterally and the spinous processes, lamina, and medial aspect of the facets were completely denuded of soft tissue. The spinous processes and laminae are exposed from C2-C7 laterally as far as lateral border of facet joints. Gutters are made bilaterally with a high-speed drill at the lamina-lateral mass junction from C3 to C6, just medial to the pedicle. The spinous process excised and are cleared off from soft tissues and preserved. The midline opening is created using a fine Kerrisonrongeur and high-speed drill. We find that a 6 mm diamond burr is useful to cut the outer cortex in the process and 2 or 3 mm Kerrison punch for removing the thin rim of remnant lamina and associated ligamentum flavum from caudal to rostral. Split lamina opened in midline using lamina spreader. French door laminoplasty was done using excised spinous processes as interlaminar spacer and were secured with titanium wire [Figure 1]. The canal diameter was increased significantly, and cord pulsation was visible intra-operatively. Post-operatively, patient improved, spasticity of limbs decreased, and patient could walk with support. Comparing pre-operative CT scan cervical spine with that of post-operative one also show significant increase in canal diameter [Figures 2 and 3]. Oyama et al. first described cervical laminoplasty in Japanese in 1973 as a treatment for OPLL. In this initial expansive laminoplasty procedure, the “Z-plasty” of the cervical spine, the spinous processes are removed, the lamina is thinned to the lamina-facet junction, and a Z-shaped cut is made between the laminae, which are opened and fixed with suture or wire.[3] Hirabayashi et al. simplified the Z-plasty described by Oyama in the early 1980s with his unilateral expansive open-door laminoplasty. In this technique, a hinge is created on one side of the lamina-spinous process-ligamentum flavum complex. This allows the roof of
a
b
Figure 1: Intra-operative picture showing: Gutter on each side of the lamina-facet junction and midline liminotomy after excision of spinous process (a). Excised spinous processes used as interlaminar spacer and were secured with titanium wire (b)
Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
Copyright of Neurology India is the property of Medknow Publications & Media Pvt. 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.
2. 3. 4. 5.
Ersahin Y, Mutluer S, Damirtas E. Intraosseous neurinoma of the parietal bone. Childs Nerv Syst 2000;16:181-3. Celli P, Cervoni L, Colonnese C. Intraosseous schwannoma of the vault of the skull. Neurosurg Rev 1998;21:158-60. Ito S, Mandai T, Ishida K, Deguchi H, Hata T, Irei I, et al. Intraosseous schwannoma of the mandible: A case report. Kawasaki Med J 2009;35:249-52. Ramina R, Mattei TA, Sória MG, da Silva EB Jr, Leal AG, Neto MC, et al. Surgical management of trigeminal schwannomas. Neurosurg Focus 2008;25:E6. Access this article online Quick Response Code:
Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.132447
Received: 19-02-2014 Review completed: 13-03-2014 Accepted: 06-04-2014
Absence status epilepsy: Report of a rare electro-clinical syndrome Sir, We report a patient with “absence status epilepsy” and discuss the features specific to this syndrome. A 49-year-old presented with an acute confusional state, which lasted for more than 24 hours. There was
no family history of seizures. From the age of 16, he started getting generalized tonic-clonic seizures (GTCS) at yearly intervals for 5 years, which subsequently became very infrequent. He was on 500 mg of sodium valproate. From the age of 20, he used to have episodes of confusion and unresponsiveness lasting for hours precipitated by sleep deprivation and emotional disturbances. He used to recover after a nap. These episodes became more frequent and prolonged, interfering with official work and necessitating multiple hospital admissions. There was no history of myoclonic jerks. At admission, he was confused. An urgent video-electroencephalography (EEG) was performed, which showed continuous runs of generalized spike-wave (SW) discharges at 3 Hz [Figure 1a]. He was partially responsive during these events and the discharges became discontinuous when aroused [Figure 1b]. Intravenous lorazepam 2 mg aborted the absence status [Figure 2a]. Subsequently he had intermittent runs of generalized SW discharges at 3 Hz lasting 10-20 seconds, which tapered-off over the next two hours when he recovered completely clinically and electrically. The inter-ictal record showed frontally dominant and generalized fast SW discharges [Figure 2b] suggestive of idiopathic generalized epilepsies (IGE). Hyperventilation and photic stimulation did not activate the discharges. Magnetic resonance imaging (MRI) of brain was normal and ring chromosome-20 was negative. He was put on 1 gm of sodium valproate and is event-free for the past six months. Absence status epilepticus (AS) is a prolonged and non-convulsive seizure occurring in various circumstances. International League Against Epilepsy
a
b Figure 1: EEG showing continuous runs of 3 Hz spike and wave discharges (a) with periods of discontinuity on asking questions (b)
224
Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
[Downloaded free from http://www.neurologyindia.com on Thursday, May 15, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Letters to Editor
a
b Figure 2: EEG following intravenous lorazepam showing disappearance of the status. (a) Interictal EEG showing the generalized discharges suggesting Idiopathic Generalized Epilepsy (b)
(ILAE) diagnostic scheme considers AS as a subtype of generalized status epilepticus.[1] Typical AS, occurs in the setting of all IGEs, especially in juvenile absence epilepsy (JAE), and atypical AS occurs in symptomatic generalized epilepsies. In 2008, Genton et al., described a new epilepsy syndrome in 11 patients with AS as their predominant or only seizure manifestation and so he proposed the name “absence status epilepsy”.[2] Herein, we describe a patient in whom the main seizure type is recurrent AS, infrequent GTCS, and no typical absences (TA). The onset of AS is after puberty and the prognosis is favorable on adequate treatment. Emotional disturbances, sleep deprivation and inadequate dose of sodium valproate were the triggering factors. The EEG findings as well as normal neurological and MRI findings supported IGE. Our patient is different from the well-known syndromes of IGE associated with AS, namely Juvenile myoclonic epilepsy (JME), JAE or IGE with phantom absences.[3,4] His electro-clinical features fit into the AS syndrome, described by Genton and colleagues.[2] Absence status epilepsy is described with onset in puberty or early adulthood. The predominant seizure type is recurrent AS. Unlike the other better known absence syndromes, TAs are extremely rare or absent. GTCS is infrequent. This syndrome lacks positive family history. There is no photoparoxysmal response, and activation to hyperventilation is rare. The interictal EEG shows normal background activity and generalized spike and wave, and polyspike and wave discharges of 2-4 Hz frequency. The seizure Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
control is generally excellent with adequate doses of sodium valproate. This atypical presentation of prolonged confusional state would make us think of complex partial status resulting in the use of inappropriate drugs. Also, inadequate dosage of drugs including that of sodium valproate could increase the incidence of AS and GTCS. Recognizing AS as a separate syndrome would thus help in earlier identification and appropriate and adequate treatment.
Rajesh Shankar Iyer, S. R. Nisha Department of Neurology, K. G. Hospital and Post Graduate Medical Institute, Coimbatore, Tamil Nadu, India E-mail: [email protected]
References 1.
2. 3. 4.
Engel J Jr. International League Against Epilepsy (ILAE). A proposed diagnostic scheme for people with epileptic seizures and with epilepsy: Report of the ILAE Task Force on Classification and Terminology. Epilepsia 2001;42:796-803. Genton P, Ferlazzo E, Thomas P. Absence status epilepsy: Delineation of a distinct idiopathic generalized epilepsy syndrome. Epilepsia 2008;49:642-9. Agathonikou A, Panayiotopoulos CP, Giannakodimos S, Koutroumanidis M. Typical absence status in adults: Diagnostic and syndromic considerations. Epilepsia 1998;39:1265-76. Panayiotopoulos CP, Koutroumanidis M, Giannakodimos S, Agathonikou A. Idiopathic generalized epilepsy in adults manifests by phantom absences, generalised tonic-clonic seizures, and frequent absences status. J Neurol Neurosurg Psychiatry 1997;63:622-7.
225
[Downloaded free from http://www.neurologyindia.com on Thursday, May 15, 2014, IP: 202.177.173.189] || Click here to download free Android application for this journal Letters to Editor
Access this article online Quick Response Code:
Website: www.neurologyindia.com PMID: *** DOI: 10.4103/0028-3886.132448
Received: 08-01-2014 Review completed: 08-01-2014 Accepted: 06-04-2014
Modified French door laminoplasty using autologous spinous process as interlaminar spacer Sir, Laminoplasty is one surgical option to treat multilevel cervical spondylotic myelopathy, especially when associated with ossified posterior longitudinal ligament (OPLL) and spinal canal stenosis.[1] Posterior approaches to decompress multilevel cervical spinal cord compression include laminectomy, laminectomy with fusion, and laminoplasty. Laminectomy safely brings adequate decompression of the cervical spinal cord; nevertheless, it can have the adverse outcomes of epidural scar formation (post-laminectomy membrane) after cervical laminectomy and of post-laminectomy kyphosis secondary to iatrogenic destabilization of the cervical spine.[2] Laminoplasty allows the spinal cord and the neuro-foramen to be decompressed without directly removing anterior pathology. By preserving the dorsal elements of the spine, laminoplasty preserves spine stability and alignment and decreases the risk of post-laminectomy kyphosis and instability.[1] A 42-year-old male with insidious onset of neck pain radiating to both hands and weakness of both upper and lower limb for last eight month complained of progressive difficulty in walking with spasticity of lower limbs and became bedridden since last one month with a pre-op Nurick grade 5. He had atrophy of the small muscles of hand, spastic gait and 4/5 weakness of the muscles of upper limb and 3/5 over lower limb and grip weakness bilaterally. Deep tendon reflexes were exaggerated. The plantar reflexes were extensor bilaterally, and there were sustained clonus at the ankles. Magnetic resonance imaging (MRI) of the cervical spine and computed tomography (CT) scan demonstrated circumferential stenotic levels at C3-C4, C4-C5, and C6-C7 due to disc herniation and OPLL. Through posterior approach, following midline dissection 226
along the avascular subperiosteal plane, paraspinal muscles are retracted laterally and the spinous processes, lamina, and medial aspect of the facets were completely denuded of soft tissue. The spinous processes and laminae are exposed from C2-C7 laterally as far as lateral border of facet joints. Gutters are made bilaterally with a high-speed drill at the lamina-lateral mass junction from C3 to C6, just medial to the pedicle. The spinous process excised and are cleared off from soft tissues and preserved. The midline opening is created using a fine Kerrisonrongeur and high-speed drill. We find that a 6 mm diamond burr is useful to cut the outer cortex in the process and 2 or 3 mm Kerrison punch for removing the thin rim of remnant lamina and associated ligamentum flavum from caudal to rostral. Split lamina opened in midline using lamina spreader. French door laminoplasty was done using excised spinous processes as interlaminar spacer and were secured with titanium wire [Figure 1]. The canal diameter was increased significantly, and cord pulsation was visible intra-operatively. Post-operatively, patient improved, spasticity of limbs decreased, and patient could walk with support. Comparing pre-operative CT scan cervical spine with that of post-operative one also show significant increase in canal diameter [Figures 2 and 3]. Oyama et al. first described cervical laminoplasty in Japanese in 1973 as a treatment for OPLL. In this initial expansive laminoplasty procedure, the “Z-plasty” of the cervical spine, the spinous processes are removed, the lamina is thinned to the lamina-facet junction, and a Z-shaped cut is made between the laminae, which are opened and fixed with suture or wire.[3] Hirabayashi et al. simplified the Z-plasty described by Oyama in the early 1980s with his unilateral expansive open-door laminoplasty. In this technique, a hinge is created on one side of the lamina-spinous process-ligamentum flavum complex. This allows the roof of
a
b
Figure 1: Intra-operative picture showing: Gutter on each side of the lamina-facet junction and midline liminotomy after excision of spinous process (a). Excised spinous processes used as interlaminar spacer and were secured with titanium wire (b)
Neurology India | Mar-Apr 2014 | Vol 62 | Issue 2
Copyright of Neurology India is the property of Medknow Publications & Media Pvt. 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.
