The authors describe their experience with the diagnosis and treatment of medial cervical cysts and fistulas which they include among disorders of thyroid gland development. In the diagnosis of medial cervical cysts the authors consider apart from sonographic examination of the neck cytological examination of maternal from aspiration thin needle biopsy as very useful. Radical surgical removal of medial cervical cysts and fistulas is the method of choice in treatment. The authors describe favurable experience with removal of cysts involving resection of the body of the hyoid bone (Schlange’s operation). They were faced with a relapse only in case of an extirpation of a cyst without resection of the body of the hyoid bone. The authors do not recommend less radical procedures because of possible development of a medial cervical fistula. In case of a malignant tumour (diferentiated thyroid carcinoma) in the medial cervical cyst, relapse of a cyst or fistula, the authors recommend a more radical procedure - surgery with resection of the hyoid bone and residual tisues of the duct in the direction towards the root of the tongue (Sistrunk’s operation). The authors accept a conservative approach of „watch and wait“ in child patients if the medical cervical cysts does not cause functional difficulties.

        Key words: medial cervical cysts, medial cervical fistula, diagnosis, Sistrunk’s operation Schlange’s operation, treatment.