As compared to cranial nerve palsy after local anaesthesia infiltration for dental and other maxillofacial interventions,1-4 cranial nerve palsy is rarely reported following local anaesthetic infiltration for image-guided parotid region intervention. However, the parotid region contains a dense concentration of neurovascular structures, including the extracranial facial nerve trunk and the retrostyloid compartment, which houses cranial nerves IX, X, XI and XII. As a result, inadvertent spread of local anaesthetic or procedural manipulation may transiently impair neural function. After obtaining patient consent to share, we report a case of acute transient palsy affecting multiple cranial nerves occurring after computed tomography (CT)-guided parotid gland biopsy performed under sedation. A 40-year-old female (55 kg) with a history of adenoid cystic carcinoma of the right parotid gland – previously resected in multiple surgeries – presented with recurrent facial nerve pain and right ear fullness. Pre-operative vital signs, physical examination and laboratory investigations were unremarkable. Sedation was initiated with intravenous midazolam (2 mg), fentanyl (100 μg in divided doses), propofol (200 mg) and ketamine (20 mg). Under CT guidance, the interventional oncology/body imaging team administered 15 mL of 1% lidocaine. The procedure lasted 27 min without intra-procedural complications. Upon arrival to the recovery area, the patient was observed to have developed right facial droop and inability to elevate the right eyebrow (cranial nerve VII affected), dysphagia and hoarseness of voice (cranial nerves IX and X affected) and right deviation of tongue (cranial nerve XII affected); however, no sensory or motor deficits were observed in the extremities. The symptoms were attributed to likely local anaesthetic spread affecting adjacent cranial nerve pathways. She remained haemodynamically stable and was observed in the recovery area, with complete resolution of symptoms within 90 min. It could not be ascertained whether instilled lidocaine affected multiple cranial nerves peripherally (inadvertent extracranial spread) and/or centrally (inadvertent intracranial spread) secondary to unpredictable neurovascular and neuraxial anatomy in the parotid region after extensive surgical history Figure 1. Essentially, this case highlights an unusual presentation of transient palsy affecting multiple cranial nerves following CT-guided parotid biopsy, thus underscoring the importance of recognising this unusual complication when vigilantly monitoring for patient safety and concurrently managing patient anxiety.Figure 1: Computed tomography image in transverse plane depicting soft and bony tissue defect (white arrowhead) around the right parotid region secondary to extensive surgical historyAuthors’ contribution All authors managed the case perioperatively; AE wrote the initial draft; MI and HDA reviewed and edited; all authors finalised the submission. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.
Elhamrawy et al. (Fri,) studied this question.