|Year : 2021 | Volume
| Issue : 2 | Page : 227-228
Isolated traumatic chiasmal syndrome with hemifield slide phenomenon: A case report
Sabyasachi Chakrabarty1, Padmavathy Maharajan2, Hridya Hareendran3, Fathima Allapitchai1, Anuraag Gandhi1, Meenakshi Ravindran1
1 Department of Paediatric Ophthalmology and Strabismus, Aravind Eye Hospital and PG Institute of Ophthalmology, Tirunelveli, Tamil Nadu, India
2 Department of Neurophthalmology, Aravind Eye Hospital and PG Institute of Ophthalmology, Tirunelveli, Tamil Nadu, India
3 Department of General Ophthalmology, Aravind Eye Hospital and PG Institute of Ophthalmology, Tirunelveli, Tamil Nadu, India
|Date of Submission||30-Mar-2020|
|Date of Acceptance||06-Sep-2020|
|Date of Web Publication||01-Apr-2021|
Dr. Sabyasachi Chakrabarty
Aravind Eye Hospital and PG Institute of Ophthalmology, Tirunelveli. 1, S N High Road, Tirunelveli - 627 001, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Keywords: Hemifield slide phenomenon, stereo-typoscope, traumatic chiasmal syndrome
|How to cite this article:|
Chakrabarty S, Maharajan P, Hareendran H, Allapitchai F, Gandhi A, Ravindran M. Isolated traumatic chiasmal syndrome with hemifield slide phenomenon: A case report. Indian J Ophthalmol Case Rep 2021;1:227-8
|How to cite this URL:|
Chakrabarty S, Maharajan P, Hareendran H, Allapitchai F, Gandhi A, Ravindran M. Isolated traumatic chiasmal syndrome with hemifield slide phenomenon: A case report. Indian J Ophthalmol Case Rep [serial online] 2021 [cited 2021 Jul 29];1:227-8. Available from: https://www.ijoreports.in/text.asp?2021/1/2/227/312416
| Case Report|| |
A 28-year-old gentleman presented after a head injury, with bilateral defective vision. His best-corrected visual acuity was 20/40 and 20/60 in the right and left eyes respectively with normal anterior and posterior segment findings. A CT scan revealed a right frontal bone fracture with pneumocephalus [Figure 1]. His visual field analysis showed a bitemporal hemianopia with high false-negative errors [Figure 2]a. An Optical Coherence Tomography of his macular ganglion cell complex revealed a predominantly bi-nasal thinning of this layer [Figure 2]b. In his pattern-reversal VEP, there was attenuation and increased latency of the P100 wave, bilaterally [Figure 3]. All these findings indicated a traumatic chiasmal syndrome. He was treated with systemic steroids but the hemianopia persisted.
|Figure 1: Computed tomography scan (axial section) showing a fracture of the right frontal bone (red arrow). Radiolucent pockets are seen in the anterior cranial fossa (yellow arrow) and the pericranial soft tissues suggestive of pneumocephalus with subcutaneous emphysema|
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|Figure 2: (a) Greyscale images from the static automated perimetry report showing a bitemporal hemianopia. There were high false-negative errors in both the sides. (b) Optical Coherence Tomography of the macular Ganglion Cell Complex showing a predominantly nasal thinning of this layer in both the eyes|
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|Figure 3: Pattern-reversal visual evoked potential recording in our patient. (a) Waveform recordings and latency period of the waves for the right eye. (b) Waveform recordings and latency period of the waves for the left eye|
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A month later, he developed a binocular diplopia, with a comitant exotropia of 12Δ for near and distance and no limitation of extraocular movements. These findings suggested the development of hemi-field slide. His diplopia was successfully treated with prism glasses (5Δ base-in bilaterally) and his reading difficulty was relieved with a stereo-typoscope [Figure 4].
|Figure 4: Stereo-typoscope. (a) Close up view of the stereo-typoscope. (b) Stereo-typoscope being used to read a newspaper|
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| Discussion|| |
A hemi-field slide may occur in bitemporal hemianopias due to an inability to fuse images in the presence of normal retinal correspondence. Fusional exercises, prisms or surgical correction may be tried, but the diplopia is likely to progressively worsen., In these cases, a stereo-typoscope can be prescribed to overcome a hemi-field slide for near. The surface of this instrument has high-contrast vertical stripes, which provide a strong stimulus for fusion by generating a midline stereo-disparity.
Our patient had an interpupillary distance of 58 mm for near. At 33 cm, his convergence requirement was 17.58Δ. With a 7 mm thickness, the convergence requirement at the anterior surface of the stereo-typoscope was 17.96Δ. This crossed disparity of 0.38Δ for peripheral fusion enabled him to read comfortably for prolonged periods.
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
Conflicts of interest
There are no conflicts of interest.
| References|| |
Brecelj J, Denislic M, Skrbec M. Visual evoked potential abnormalities in chiasmal lesions. Doc Ophthalmol 1989;73:139-48.
Elkington SG. Pituitary adenoma. Preoperative symptomatology in a series of 260 patients. Br J Ophthalmol 1968;52:322-8.
Ko TC, Wu PKW, Lo BKK. Hemifield slide phenomenon in a patient with bitemporal hemianopia. HKJ Ophthalmol 1999;3:48-50.
van Waveren M, Jägle H, Besch D. Management of strabismus with hemianopic visual field defects. Graefes Arch Clin Exp Ophthalmol 2013;251:575-84.
Peli E, Satgunam P. Bitemporal hemianopia; its unique binocular complexities and a novel remedy. Ophthalmic Physiol Opt 2014;34:233-42.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]