Lentiform fork sign in a child with dialysis disequilibrium syndrome: A transient MRI pattern which emphasizes neurologic consequence of metabolic acidosis

Teaching Neuro Images : The lentiform fork sign: An MRI pattern of metformin-associated encephalopathy

“…This report may have misled readers into thinking not only that the lentiform fork sign resulted from metformin-related encephalopathy, but also that the referenced da Rocha et al 2 case was one of metformin-associated encephalopathy. da Rocha et al 2 described a case of dialysis disequilibrium syndrome with no reference to metformin. The authors also failed to cite Kumar and Goyal 3 as the original contributors of the lentiform fork sign.…”

“…Rieder, Leonardo Vedolin, Lillian Campos, Tássia Koltermann, Porto Alegre, Brazil: The authors thank Dr. Kaiwar for his comments on our article. 1 Kumar and Goyal 3 and da Rocha et al 2 highlighted metabolic acidosis as a possible mechanism for the lentiform fork sign, describing it in uremic encephalopathy and dialysis disequilibrium syndrome. However, a case described by Jung et al 4 with extrapyramidal features and a similar MRI finding was associated with metformin in a hemodialysis patient without metabolic acidosis.…”

Uremic Encephalopathy: MR Imaging Findings and Clinical Correlation

“…The LFS may also be present in metabolic acidosis from any cause, including end-stage renal disease, methanol intoxication, and the dialysis disequilibrium syndrome. [1][2][3][4][5][6] This study was undertaken to describe the MR imaging features in the brains of 10 patients with UE, with the aim of identifying common imaging features and potentially clarifying the possible pathophysiology of UE.…”

Lentiform fork sign: Uremia alone or multifactorial causation?

“…Involvement of basal ganglia is more common in Asian patients with diabetes mellitus. [5][6][7] Some authors have proposed that the lentiform fork sign is an early and reliable marker of UE and have shown it to resolve after intensive hemodialysis. Wang et al have demonstrated reduced to absent glucose metabolism in basal ganglia on F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in patients with diabetes and uremia and basal ganglia affliction.…”

“…4,5 This sign has been reported in patients with UE, but also with dialysis disequilibrium syndrome, and also has been proposed to be associated with metabolic acidosis of any cause. [5][6][7] Some authors have proposed that the lentiform fork sign is an early and reliable marker of UE and have shown it to resolve after intensive hemodialysis. 1 Some anecdotal reports have also attributed bilateral basal ganglia changes of diabetic uremia to demyelination as in central pontine myelinolysis.…”