Indian Journal of Medical Specialities

LETTER TO THE EDITOR
Year
: 2020  |  Volume : 11  |  Issue : 2  |  Page : 109--110

Owl's eye sign: A rare neuroimaging finding


Abhishek Juneja, Kuljeet Singh Anand, Arpit Agrawal 
 Department of Neurology, Dr. RML Hospital, New Delhi, India

Correspondence Address:
Dr. Abhishek Juneja
A-15, Old Quarters, Ramesh Nagar, New Delhi - 110 015
India




How to cite this article:
Juneja A, Anand KS, Agrawal A. Owl's eye sign: A rare neuroimaging finding.Indian J Med Spec 2020;11:109-110


How to cite this URL:
Juneja A, Anand KS, Agrawal A. Owl's eye sign: A rare neuroimaging finding. Indian J Med Spec [serial online] 2020 [cited 2022 Jul 5 ];11:109-110
Available from: http://www.ijms.in/text.asp?2020/11/2/109/289116


Full Text



Dear Editor,

A 28-year-old male patient presented with complaints of wasting and weakness of the left upper limb for 1 year. He also complained of involuntary muscle twitching over his left arm and forearm. On neurological examination, he had wasting of the left hand and forearm muscles with diffuse fasciculations over the left arm and forearm. He had weak hand grip on the left side along with weak flexion and extension across the left elbow joint. Deep tendon reflexes were exaggerated in all four limbs. Plantar response was bilaterally flexor. The rest of the neurological examination was unremarkable. His routine blood investigations were normal including glycemic and thyroid profile. His serum antinuclear antibody and human immunodeficiency virus tests were negative. His nerve conduction studies were normal. Electromyography done per motor neuron disease protocol revealed spontaneous activity, in the form of diffuse fasciculations in bilateral upper and lower limbs and paraspinal and tongue muscles. Large amplitude giant muscle unit action potentials with reduced interference pattern were noted in most of the sampled muscles. The patient was diagnosed as a case of laboratory-supported probable amyotrophic lateral sclerosis (ALS) as per revised El Escorial criteria. Magnetic resonance (MR) imaging of the cervical spine revealed linear T2 intramedullary hyperintensity in C3–C5 cervical segments, which on axial cuts had the appearance of owl's eyes [Figure 1]. The patient was told the prognosis of his illness and started on tablet riluzole 50 mg twice daily. He was registered in the Department of Physical Medicine and Rehabilitation.{Figure 1}

The “owl's eye” sign is also known as “snake-eye” sign. It is characterized by bilaterally symmetrical hyperintensity in the anterior horn of the spinal cord in axial T2-weighted MR imaging.[1] It has been reported in various diseases including cervical spondylosis, Hirayama disease, spinal cord infarction, neuromyelitis optica, and flail arm syndrome.[2],[3] It is possibly secondary to cystic necrosis in the central gray matter near the ventrolateral posterior column of the spinal cord. It is regarded as a poor prognostic factor for the recovery of upper-extremity motor weakness as found in our case.[4] It is a rare neuroimaging finding and ALS should be kept in mind, apart from the more common ischemic and mechanical causes, as a differential diagnosis.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

None.

Conflicts of interest

There are no conflicts of interest.

References

1Faiss JH, Schroth G, Grodd W, Koenig E, Will B, Thron A. Central spinal cord lesions in stenosis of the cervical canal. Neuroradiology 1990;32:117-23.
2Lebouteux MV, Franques J, Guillevin R, Delmont E, Lenglet T, Bede P, et al. Revisiting the spectrum of lower motorneuron diseases with snake eyes appearance on magnetic resonance imaging. Eur J Neurol 2014;21:1233-41.
3Kumar S, Mehta VK, Shukla R. Owl's eye sign: A rare neuroimaging finding in flail arm syndrome. Neurology 2015;84:1500.
4Mizuno J, Nakagawa H, Inoue T, Hashizume Y. Clinicopathological study of “snake-eye appearance” in compressive myelopathy of the cervical spinal cord. J Neurosurg 2003;99:162-8.