Dorsal Midbrain Syndrome

In this module we discuss a patient presentation demonstrating dorsal midbraine syndrome (AKA Parinaud syndrome). Its purpose is to aid in teaching fellow providers how to recognize the clinical findings of dorsal midbrain syndrome by reviewing the relevant anatomy, exploring the etiologies of its presentation, and discussing the next steps for management.

Dorsal Midbrain Syndrome John R. Mark, MD Nandini Gandhi, MD Yin Allison Liu, MD, PhD UC Davis Eye Center, Sacramento, CA Learning Objectives • Recognize the clinical findings of dorsal midbrain syndrome • Review the relevant anatomy to localize the lesion • Explore the etiologies of its presentation • Discuss the next steps for management HPI • A 69-year-old man with acute myeloid leukemia from primary myelofibrosis status post allogenic stem cell transplant, who is admitted for failure to thrive in the setting of subacute total body weakness and psychomotor slowing. • Ophthalmology consulted for binocular double vision. Presentation Image created using 9 Gaze app. Learn more here. Ophthalmic Examination Findings OD -4 -4 0 -1 -1 OS -4 -4 0 0 -1 -1 -4 -4 0 -1 -1 • Prominent upgaze palsy • Skew deviation • Note: eyelid retraction here is with upgaze, which is not consistent with “Collier sign. He also did not demonstrate lightnear dissociation or convergence-retraction nystagmus. MRI images Axial T2 FLAIR – hyperintensity of the medial bilateral thalami along the tegmentum of midbrain and dorsal pons with facilitated diffusion MRI Images Cont. January 29th, 2024 June 6th, 2024 Axial T2 FLAIR – Interval new and progressed abnormal signal alteration within the midbrain Dorsal Midbrain Syndrome AKA “Parinaud Syndrome” • Constellation of findings stemming from disruption of the supranuclear and internuclear within the dorsal midbrain • Lid retraction “Collier sign” • Convergence retraction • Light-near dissociation nystagmoid movement • Upgaze paresis • Thalamic esotropia Anatomy and Pathway By Madhero88 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6811879 Signs • Lid retraction “Collier sign” • Skew deviation • Light-near dissociation • Up-gaze paresis • Convergence-retraction nystagmoid movement This “Parinaud Triad” is thought to be present in only about 65% of cases1 Convergence-Retraction “Nystagmus” • Convergence and retraction of the globes • Most prominent in upgaze • • • Caused by simultaneous contraction of bilateral EOMs with medial rectus overpowering the lateral Stems from by interruption of the midbrain posterior commissure Not a true nystagmus, but rather adducting saccades causing convergence of both eyes, without any slow phase Video: Maramattom, B. V. (n.d.). Ocular retraction nystagmus: Neurology clinical [Video]. GrepMed. https://img.grepmed.com/uploads/15235/ocular-retraction-nystagmus-neurologyclinical-original.mp4 Photo: https://entokey.com/wp-content/uploads/2016/06/B978032303656650024X_f19-25-9780323036566.jpg Management • MRI is recommended for suspected dorsal midbrain syndrome • Studies and treatment depends on suspected etiology • Flow cytometry showed leukocyte pleocytosis without malignant cells, making CNS lymphoma less likely • Our patient’s etiology was suspected to be progressive multifocal leukoencephalopathy (PML) secondary to medication vs JC virus – which was confirmed on CSF PCR References 1. Shields, Melissa et al. “Parinaud syndrome: a 25-year (1991-2016) review of 40 consecutive adult cases.” Acta ophthalmologica vol. 95,8 (2017): e792-e793. doi:10.1111/aos.13283 2. “Dorsal midbrain syndrome, Parinaud syndrome.” YouTube, uploaded by Neuro-Ophthalmology with Dr. Andrew G. Lee, 18 December 2017, https://www.youtube.com/watch?v=c32F374ZiGI 3. By Madhero88 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6811879 4. 9 Gaze app. Distributed by See Vision, LLC. Available in the App Store Author Information • Name: John Robert Mark, M.D. • Title: Resident Physician • Affiliation: Department of Ophthalmology, University of California, Davis • Financial Disclosures: None • Address: 4860 Y Street Tschannen Eye Institute, Sacramento, CA 95817 • Email: [e-mail] Co-Author Information • Name: Nandini Gandhi, M.D. • Title: Professor of Ophthalmology • Affiliation: Department of Ophthalmology, University of California, Davis • Financial Disclosures: None • Address: 4860 Y Street Suite 1E, Sacramento, CA 95817 • Email: [e-mail] Co-Author Information • Name: Yin Allison Liu, M.D., Ph.D. • Title: Associate Professor of Neuro-Ophthalmology • Affiliation: Departments of Ophthalmology, Neurology, and Neurological Surgery, University of California, Davis • Financial Disclosures: None • Address: 4860 Y Street Suite 1E, Sacramento, CA 95817 • Email: [e-mail] Special thank you to our volunteer patient who consented to have his case discussed and photographs shared to further medical education. Additional thanks to Dr. Neha Antil, M.D. for assisting with neuroradiology images.