Posterior pituitary bright spot

The posterior pituitary bright spot is an MRI feature of the normal pituitary gland. It refers to the intrinsically high T1 signal of the posterior pituitary thought to be from the storage of vasopressin, which has a T1-shortening effect 2.

It is important to note that a posterior pituitary bright spot is not identified in all patients, but rather somewhere between 50-100% 1,2

Radiographic features

MRI
  • oval/round high T1 signal, best seen on sagittal images in the posterior aspect of the pituitary fossa
  • normal measurements (decreasing size with age) 1,2
    • long axis: 1.2-8.5 mm
    • short axis: 0.4-4.4 mm

Related pathology

The absence of posterior pituitary bright spot should prompt the consideration of the following (noting it may be absent in normal patients): 

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Article information

rID: 38816
Section: Signs
Synonyms or Alternate Spellings:
  • Posterior pituitary bright spot (PPBS)
  • Pituitary hyperintense spot

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Cases and figures

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    Case 1: normal
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    Case 2: normal
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    Case 3: ecoptic posterior pituitary
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    T1 sagittal image...
    Case 4: absent in diabets insipidus
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