Facial Nerve Monitoring under Different Levels of Neuromuscular Blockade with Cisatracurium Besilate in Parotid Tumour Surgery

Background. Anaesthesia can alter neuronal excitability and vascular reactivity and ultimately lead to neurovascular coupling. Precise control of the skeletal muscle relaxant doses is the key in reducing anaesthetic damage. Methods. A total of 102 patients with the normal functioning preoperative facial nerve who required parotid tumour resection were included in this study. Facial nerve monitoring was conducted intraoperatively. The surgeon stimulated the facial nerve at different myorelaxation intervals at TOF% (T4/T1) and T1% (T1/T0) and recorded the responses and the amplitude of electromyogram (EMG). Body movements (BM) or patient-ventilator asynchrony (PVA) was recorded intraoperatively. Results. In parotid tumour resection, T1% should be maintained at a range of 30 to 60% while TOF% should be maintained at a range of 20 to 30%. Analysis of the decision tree model for facial nerve monitoring suggests a partial muscle relaxation level of 30 % < T 1 % ≤ 50 % and TOF ≤ 60 % . A nomogram prediction model, while incorporating factors such as sex, age, BMI, TOF%, and T1%, was constructed to predict the risk of BM/PVA during surgery, showing good predictive performance. Conclusions. This study revealed an adequate level of neuromuscular blockade in intraoperative parotid tumour resection while conducting facial nerve monitoring. A visual nomogram prediction model was constructed to guide anaesthetists in improving the anaesthetic plan.

Prospective Study on Effectiveness of Facial Nerve Monitoring in Improving the Surgical Outcomes for Parotidectomy of Benign Parotid Tumours in a Tertiary Hospital in South India

BACKGROUND Salivary gland diseases are rare but an important group of disorders. Following surgeries involving the parotid gland, facial nerve paresis is a common postoperative complication. The reported worldwide incidence of facial nerve paresis following parotidectomy is approximately 20 - 60 %. We need to determine the incidence of facial nerve paresis in the post-operative period following superficial, adequate, or extra-capsular parotidectomy of benign parotid tumours with the use of intraoperative facial nerve monitoring. METHODS A non-randomised interventional trial was initiated once cleared by the institutional review board. With the calculated sample size of 44, the patients underwent nervemonitoring for the identification of the branches of the facial nerve. Clinical grading of the nerve function was done using the House-Brackmann score on the postoperative days 2, 7, and 60. The findings were compared with the historical controls (HC) of 53 patients who underwent similar procedures but with no intraoperative facial nerve monitoring. All patients were recruited in continuity for over two years. RESULTS The incidence of facial nerve paresis was 30 - 40 % and 10 - 20 % in the historical control and nerve monitoring group, respectively (P = 0.07). The duration of surgery in the nerve monitoring group was 83 ± 30 minutes and 95 ± 15 minutes in the HC group. The incidence of nerve paresis was similar among the trainees and consultants suggestive of adequate training. CONCLUSIONS Intraoperative facial nerve monitoring is a useful adjunct to reduce the incidence of early postoperative facial nerve paresis. The technique would not prolong the duration of the procedure. The technique may be utilized safely on a routine basis even during surgical training. KEYWORDS Facial Nerve Monitoring, Parotidectomy, Benign Parotid Tumour, HouseBrackmann Score

Parapharyngeal lipoma mimicking parotid tumour in a 4-year-old boy

Parapharyngeal space tumour is rare in paediatrics. It can either be a primary tumour arising from parapharyngeal space structures, an extension from the surrounding structures or a metastatic tumour. In adults, salivary gland tumours and paragangliomas are common, while neurogenic tumours predominate in paediatrics. The delicate anatomy in the parapharyngeal space makes the diagnostic procedures more complex, especially in paediatrics. Although tissue biopsy can be obtained under sedation or local anaesthesia, it is histologically difficult to differentiate lipoma from liposarcoma. We present a paediatric case with a large parapharyngeal space mass in a 4-year-old boy and the management used.

Skull base chondroblastoma presenting as a deep lobe parotid tumour

Chondroblastomas are rare, benign cartilage-producing primary bone tumours that account for 1% of all primary bone tumours. They are usually seen in young adult males and affect long tubulous bones such as the femur or humerus. Occurrences in non-tubular flat bones such as the craniofacial skeleton do occur but are seen in older adults. With only around 100 cases reported in the English literature, ‘Temporal Bone Chondroblastomas’ can present a diagnostic challenge for both surgeon and histopathologist. Clinical presentation can be subtle and patients may have longstanding symptoms due to compression of surrounding structures. Imaging in the form of contrast CT and/or MRI is recommended to assess size, proximity to neurovascular structures and plan operative approach. Definitive treatment is surgical excision, with radiotherapy reserved for recurrence or unfit surgical patients. Long-term follow-up is recommended for surveillance due to high recurrence rates. We present our experience managing this rare entity.

PLEOMORPHIC ADENOMA IN AN UNUSUAL SITE

Pleomorphic adenoma is also called as mixed parotid tumour, which is a benign neoplasm of the salivary gland, occurring more frequently in major salivary gland. It occurs infrequently in minor salivary glands. It can involve the palate and lips as well. The aim of this paper is to report the case of a 24 year old male, admitted in Saveetha medical college and hospital, with complaints of swelling in the upper lip for 6 months, which was successfully diagnosed as pleomorphic adenoma and treated with surgical excision.

Management of the neck in malignant parotid neoplasm

<p class="abstract">Parotid gland cancer (PGC) are rare and accounts for 3% of all head and neck malignancies.The classification of parotid tumour is complex and comprises both benign and malignant neoplasms of epithelial and non-epithelial origin.There is marked variation in the histological features of these tumours,therefore treatment options of parotid cancer is widely varied.Lymph node metastasis to the neck is one of the most important factors in therapy and prognosis for patients with parotid malignancy. This article reviews the literature regarding neck management of parotid cancer in cases of both clinically positive (cN+) and clinically negative (cN-) neck nodes. The literature search was performed using Google search engine, PUB Med to identify relevant articles on recommendations for neck management in patients with parotid cancer in cases of both clinically positive (cN+) and negative (cN-) neck nodes. Due to the rarity of parotid cancer and the wide histopathological varieties, the literature was hard to interpret. There is a consensus about managing clinically positive neck with therapeutic neck dissection. Most studies agree on elective neck dissection in certain indications which are high T stage, high grade histology, facial paralysis, age, extraglandular extension, peri-lymphatic invasion. Level II to IV appears to be at higher risk and can be done through the same parotidectomy incision. The role of irradiation in cN- necks is not clear but some studies recommend its usage for curative intent and argue that it adds less morbidity than the elective neck dissection. Although the management of the neck in cN+ patients is widely agreed, controversy still exists about the need for elective neck dissection in cN- patients and the levels which should be dissected.</p>