Reply:

As indicated in our article,¹ approximately 70% of our patients with interhypothalamic adhesions had no symptoms referable to hypothalamic-pituitary dysfunction (40 of 57). We have since identified 72 additional patients, of whom 51 had no clinical symptoms. Thus, in the appropriate patient population in which associated symptoms are absent, interhypothalamic adhesions may be incidental.

Furthermore, in our experience, none of the asymptomatic patients and only 4 of the symptomatic population had additional midline abnormalities. We re-reviewed the imaging in all of our patients and found the numbers to hold true. None of the patients used for the figures had hypogenesis of the splenium or posterior periventricular white matter volume loss to cause splenium volume loss. The patient in Fig 1D did have a cavum septum pellucidum, a normal variant, but did not have partial fenestration on review of the images in 3 orthogonal planes.

Last, we agree with the Whitehead and Vezina² thesis that “the midline should be closely scrutinized for additional anomalies/abnormalities in patients harboring an interhypothalamic adhesion. Only after the brain has been carefully examined and signs/symptoms have been carefully considered can an interhypothalamic adhesion be considered an incidental and isolated finding.”³ It mirrors ours, “While associations between IHAs [interhypothalamic adhesions] and other syndromes likely exist, in the appropriate patient population lacking referable symptoms and with few or no other structural abnormalities, interhypothalamic adhesions may be incidental and of no clinical significance.”