[Dealing with "complex" pain patients in eye surgery : Perioperative management of patients with pre-existing chronic pain, opioid consumption and opioid use disorder].

The quality of postoperative pain management is still considered insufficient in many cases, also in surgical ophthalmology. Complex constellations and comorbidities, such as pre-existing chronic pain, opioid consumption and opioid use disorders represent a special challenge due to psychosocial influencing factors and sometimes psychological and psychiatric comorbidities but also due to pharmacological effects, such as the development of opioid tolerance, the opioid-induced hyperalgesia. This review article aims to impart knowledge on aspects of these comorbidities and the perioperative management to improve the treatment skills of ophthalmologists in the management of pain in these complex patients.