Freezing of gait (FOG) is characterized by a temporary inability to initiate gait or sudden interruptions in forward movement, often triggered by narrow spaces or multitasking. 1 FOG is most commonly seen in parkinsonian syndromes (including vascular parkinsonism) but may also be seen in idiopathic normal pressure hydrocephalus (iNPH). 2 We describe a case of right-sided FOG following a left parietal stroke with imaging consistent with iNPH, and improvement after large-volume lumbar puncture (LP). A 62-year-old woman presented with a progressive gait decline in the last year. Three years prior, she sustained a left middle cerebral artery embolic ischemic infarct with temporal and parietal involvement, secondary to atrial fibrillation, treated with intravenous thrombolysis and endovascular thrombectomy of an M2 branch occlusion. In the weeks following the stroke she could perform tandem gait. Now, she had a mild expressive aphasia and slight right-sided weakness. She reported difficulty initiating steps with her right leg, described as feeling “left behind” while walking, and required a walker. She had no history of falls or urinary incontinence and denied cognitive changes, though formal cognitive testing was not performed, and no family history of gait disorders or parkinsonism. Examination revealed FOG with initiation, during forward walking, with turning, and crossing doorways, with improvement with cueing to march. MDS-UPDRS Part III score was 4 for FOG (question 3. 11). No resting tremor, rigidity, bradykinesia, supranuclear gaze palsy, dysautonomia, or other parkinsonian symptoms were noted on exam (Video 1, Segment 1). A Dopamine Transport Scan (DAT) was normal. MRI brain (Fig. 1) showed findings consistent with her prior infarction, a callosal angle of approximately 60°, an Evans index greater than 0. 3, and disproportionately enlarged subarachnoid space hydrocephalus (DESH). MRI did not demonstrate disproportionate midbrain atrophy. She initially deferred LP due to anticoagulation. Trials of amantadine and carbidopa-levodopa did not improve gait. She later underwent a large-volume LP with notable improvement in gait (Video 1, Segments 2 and 3). Classically, disturbances in the frontal cortex, basal ganglia, substantia nigra, and brainstem locomotor regions, as well as impaired sensorimotor and cognitive integration, contribute to FOG. 1, 3 While FOG may suggest a degenerative parkinsonian syndrome, the differential includes vascular parkinsonism, drug-induced parkinsonism, iNPH, frontal lobe tumors, and basal ganglia insults such as CO poisoning. In our patient, a normal DAT scan, absence of parkinsonian signs beyond FOG, and lack of history of exposure to dopamine-blocking agents, argue against idiopathic Parkinson's disease or atypical parkinsonism. The combination of iNPH-compatible imaging and objective improvement following LP supports iNPH as the leading etiology. The unilateral FOG may reflect reduced compensatory reserve from her prior infarct, creating relative vulnerability within the gait network. Prolonged unilateral symptoms contributed to diagnostic delay. Prior neuroimaging data revealed reduced functional connectivity along the dorsal stream of visuomotor processing, 4 particularly in the superior parietal lobule, 1 among freezers. Because this region was affected in our patient's stroke, disruption of posterior parietal compensatory mechanisms may have contributed to the unilateral presentation of FOG, driven by the underlying iNPH. (1) Research project: A. Conception, B. Organization, C. Execution; (2) Statistical Analysis: A. Design, B. Execution, C. Review and Critique; (3) Manuscript Preparation: A. Writing of the first draft, B. Review and Critique. J. P.: 1C, 3A, 3B. M. F.: 1A, 1B, 1C, 3B. J. M.: 1A, 1B, 1C, 3A, 3B. We sincerely thank the patient and her family for their generosity in allowing us to share this unique case. Ethical Compliance Statement: We confirm that the approval of an institutional review board was not required for this work. Informed consent was obtained from the subject described in this case report. We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines. Funding Sources and Conflict of Interest: No specific funding was received for this work. The authors declare that there are no conflicts of interest relevant to this work. Financial Disclosures for the Previous 12 Months: The authors declare that there are no additional disclosures to report. Author disclosures are available in the Supporting Information. Data sharing not applicable to this article as no datasets were generated or analysed during the current study. Data S1. Coidisclosures. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. 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Portales et al. (Tue,) studied this question.