We are grateful for the high level of interest in our systematic review. As we described, an empty sella is the radiological or pathological-anatomical imaging of an apparently empty sella turcia. Dr. Baiker is correct in stating that there is a remnant of pituitary tissue in our image. Indeed, we described this in the text: “This impression arises from the fact that the sella turcica is filled with cerebrospinal fluid (CSF), and the hypophyseal tissue at its base is flattened (Figure 1).” (1). The radiological definition of when an empty sella should be diagnosed is not uniform in the studies.
We support further investigations such as those from Prof. Freund and colleagues. However, the age range in the studies we included differs from that in their Correspondence letter: our systematic review referred only to adults, while the retrospective analysis of Freund et al. also included minors. Further, the mean age in the work of Freund et al. is higher than that in the studies we included. As correctly reported by Freund et al., the height of the pituitary gland as measured by magnetic resonance imaging correlates with age; thus, if the criteria are not age-adjusted, a higher average age makes it more likely to observe an empty sella.
The prevalence of empty sella of 2%–20% includes both primary and secondary forms. According to a recent study, empty sella is diagnosed in 2% of all cMRT examinations as a chance finding without apparent cause. According to our systematic review of patient cases with a pooled prevalence of pituitary insufficiency of 52%, approximately 1% of all patients would have pituitary insufficiency. When interpreting the data, we also find this to be excessively high. We suspect a publication bias, as inconspicuous findings are often not published and were thus not included in our analysis.
A finding of an empty sella does not necessarily indicate a disease, and this should be clearly communicated to the patient. Our concept is based on patient education as well as collecting blood for checking the levels of basal hormones, especially as impairment of the corticotropic axis can lead to life-threatening conditions. Doctors should be aware of this from a medical point of view, but without unsettling patients. Dr. Kopka is correct in her objection that hormones do not work according to an all-or-nothing concept, and that partial insufficiencies could exist. In our meta-analysis, therefore, only studies were included in which a stimulation test had been performed. However, for everyday clinical practice, our recommendation would be to ask for specific complaints and to initiate further stimulation tests only if abnormal basal levels are detected or if the symptoms are indicative.
On behalf of the authors:
Dr. med. Matthias K. Auer
Prof. Dr. med. Günter Karl Stalla
Dr. med. Anna Kopczak
Max Planck Institute of Psychiatry
Conflict of interest statement
Dr. Auer has received consultancy fees from Shire, and reimbursement for conference/educational event fees and travel expense from Pfizer, Ipsen, and Lilly.
Prof. Stalla has received consulting honoraria, reimbursement of conferences/educational event fees, travel expenses, and/or study support (third-party funds) from Pfizer, Ipsen, Lilly, Shire, Novartis, Sandoz, NovoNordisk, and HRA.
Dr. Kopczak declares that no conflict of interest exists.
|1.||Auer MK, Stieg MR, Crispin A, Sievers C, Stalla GK, Kopczak A: Primary empty sella syndrome and the prevalence of hormonal dysregulation—a systematic review. Dtsch Arztebl Int 2018; 115: 99–105 VOLLTEXT|