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At a glance

It is a polyglandular endocrine syndrome characterized by diabetes insipidus, mellitus, and hyperparathyroidism. Clinically, affected individual present with the classic triad of (a) hyperostosis frontalis interna, (b) adipositas, and (c) virilism and hirsutism. There is a peculiar, noninflammatory, usually benign osteopathy with symmetrical thickening of the frontal, parietal, or occipital bones as a result of deposits on the internal aspects of the squama frontalis. Other clinical features include menstrual disorders, galactorrhea, mental dysfunctions, fatigue, somnolence, visual disorders, vertigo, tinnitus, obesity, polyphagia, polydipsia, polyuria, loss of sense of smell, decreased glucose tolerance, seizures, and involvement of the second, fifth, and seventh cranial nerves with hemiplegia and hemiparesis.


Hyperostosis Frontalis Interna; Morel Syndrome; Metabolic Craniopathy.


The first description of a disorder involving frontal bone lesions (hyperostosis frontalis interna [HFI]) associated with obesity and virilism was done in 1765 by Giovanni Battista Morgagni (1682-1771), an Italian anatomist. In 1928, Roy Mackensie Steward (1889-1964) emphasized the association with obesity. Steward (1889-1964) and Ferdinand Morel (1888-1957) added clinical features that included neuropsychiatric symptoms, eg, depression and dementia. Ferdinand Morel (a Swiss psychiatrist) emphasized the accompanying menstrual disturbance, amenorrhea, and impotence. The term “Morgagni triad” was introduced by Folke Henschen in 1937, but the term “Morgagni-Stewart-Morel Syndrome” is now commonly used.


It is an extremely uncommon disorder and the incidence remains unknown. The age of onset is average 45 years old. It occurs almost exclusively in females with a prevalence of approximately 90%.

Genetic inheritance

It is probably inherited as an autosomal dominant trait. There are no reported cases of male-to-male transmission.


Unknown. The underlying defect causing excess bone formation appears to be different from normal mechanisms. The biochemical response to calcitriol and bone biopsy findings (increased number of osteoblasts) has been shown to be different. Many of the endocrine features may be related to hyperprolactinemia, which is frequently found in these cases.


Clinical supported by investigations and imaging. Hyperphosphatasemia is common. Radiologic, CT, and MRI scans confirm bony overgrowth. Audiology confirms changes in hearing.

Clinical aspects

May be almost symptomless and is found incidentally. Skull: Hyperostosis frontalis interna; as a result of progressive overgrowth, intracranial pressure may increase and lead to brain and nerve compression, cranial nerve palsies, and seizures; choanal stenosis; glaucoma. Endocrine: Obesity, hyperphosphatasemia, hyperprolactinemia, galactorrhea, diabetes mellitus, menstrual irregularity. Neuropsychiatric: “Treatable dementia.” Skin: Hypertrichosis.

Precautions before anesthesia

Assessment of severity of the endocrine and neurologic conditions. It includes a complete evaluation for raised intracranial pressure, seizures, and the patient’s medications. It is essential to review the presence of ...

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