Geruchsempfinden im Langzeitverlauf nach transkranialer Resektion von Olfaktoriusrinnenmeningeomen – eine monozentrische Studie

Olfactory groove meningiomas often lead to a reduced sense of smell and have measurable influence on quality of life. However, the interest and extent of examination of the olfactory function is quite low in everyday clinical practice.

Prospective analysis of patients who underwent transcranial resection of olfactory groove meningiomas from October 2005 to December 2022 was performed. Data on clinical presentation, pre- and postoperative neurologic examinations, operative approach, tumor size and further follow-up were recorded. Olfactory function was assessed using the extended test of Sniffin' Sticks, which consists of three parts: the odor threshold for n-butanol, the ability to discriminate different odors and identification of 16 different smells. Also information about quality of life was gained using the Questionnaire for Olfactory Dysfunction (QOD).

24 patients (6 male, 18 female, age 44.8 ± 14.5 years, follow up period of 6.7 years) were assessed. In 11/24 patients surgical approach was done via supraorbital craniotomy and in 11/24 patients a frontolateral craniotomy was performed. Also two patients received a pterional approach. In 12/24 operations endoscopic assistance was used. Average tumor volume was 13.4cm3. In 19 patients a WHO grade I tumor was detected; in 5 patients a grade II tumor was confirmed.

Fortunately, the sense of smell has been fully preserved in 9 patients. Initially in 12 patients normosmia was measured. Hyposmia was preoperative measured in 7 patients and postoperative confirmed in 6 patients, whereas anosmia increased from 5 patients to 9 patients postoperative. In summary, after excluding patients with anosmia, preservation of olfactory function was confirmed in 15/19 patients (78.9%). 7 patients stated a reduction regarding olfaction-related quality of life. 4 of these 7 patients suffer from total anosmia.

29.2% of the patients who were examined stated a reduction of olfactory-related quality of life in long-term follow up. This highlights the influence of olfactory function on everyday life and should be investigated in further studies.