To explore the main points of clinical treatment of fourth branchial cleft deformity in special positions and to provide a reference for clinical practice.

The clinical data of one case of a fourth branchial cleft deformity that occurred in the left anterior chest wall with a fistula below the clavicle are summarized and combined with a literature review.

The patient complained of repeated swelling and pain under the left anterior chest wall for 2 months. A 10 mm×10 mm fistula with yellow clear liquid exudate from the fistula was observed on the left side below the clavicle. A 20 mm×20 mm×10 mm swelling was immediately adjacent at the superficial cervicothoracic junction of the upper sternoclavicular joint, with no fluctuation and poor activity; this swelling produced slight pain upon pressing. Imaging examinations pointed to cystic lesions. The primary diagnosis was a fourth branchial deformity. A small amount of methylene blue was injected into the patient's subclavian fistula, and a supraclavicular T-shaped incision was made where the cyst contacted the fistula. By turning the flap, all the methylene blue-stained areas and adjacent submucosal tissues were exposed. During the operation, a mass was found on the sternum. The platysma was found deep in the notch, which was incised before excising the surrounding area. The pathological result is the fourth branchial cleft deformity. After 1 week and 3 months of follow-up, the patients had no discomfort and no recurrence. A review of the relevant literature shows that the fourth branchial cleft deformity is a congenital developmental abnormality that occurs in 1% of all branchial cleft deformity. It often presents as a fistula, cyst, or sinus tract and is anatomically located at the neck root and supravicular region. The fistula is close to the medial lower boundary of the sternocleidomastoid muscle. The diagnosis is often made based on its anatomical location, imaging examinations and, ultimately, pathology. The differential diagnoses include other cervical swellings, such as hemangioma and a thyroglossal duct cyst. Surgical resection is a commonly used treatment method. In recent years, endoscopic positioning and internal fistula burning have had good curative effects for recurrent fourth branchial cleft deformity, with a small chance of recurrence or cancer.

Given its unique position, clinicians should make full use of imaging methods to determine the size, anatomical location and course of the lesion when treating the fourth branchial cleft deformity to ensure the complete and safe surgical resection of the lesion and prevent recurrence.

To establish and validate a risk prediction model for postoperative delirium (POD) in patients with head and neck cancer (HNC) resection with free flap repair and to provide a reference for clinical practice.

This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. This study retrospectively collected and evaluated the risk factors and vital signs of patients undergoing head and neck cancer free flap reconstruction in the Department of Oromaxillofacial Head and Neck Oncology, Xuzhou Central Hospital from January 1, 2016, to January 1, 2022. A total of 241 cases were included, of which 171 cases were used to establish the prediction model, and 70 cases were collected for internal verification. Univariate and multivariate logistic analyses and the R Studio software package were used for modeling and statistical analysis.

The research model finally included five risk factors: age, blood transfusion, postoperative sleep disorder and postoperative VAS pain value. The area under the working characteristic curve (AUC) of the subjects in the training set of the model was 0.869 (95% CI: 0.789-0.948), the Youden index was 0.692, the predictive value was 0.215, the sensitivity was 85.3%, the specificity was 83.9%, and the goodness of fit of the Hosmer Lemeshow test was 10.336 (P =0.242). The model fit well. The validation set was verified according to the model. The C index was 0.827 (95% CI:0.681-0.973), and the model prediction effect was very good.

This model may be applied to predict postoperative delirium for patients with head and neck cancer resection and free flap repair, which has a high predictive value for the risk of HNC-POD at admission. The use of this model may help to better implement preventive treatment and nursing measures.