Computer-assisted surgery for replacement of the temporomandibular joint with customized prostheses: can we validate the results?

PURPOSE: Replacing the temporomandibular joint poses an important challenge to maxillofacial surgeons, and for certain disorders, it represents the treatment's gold standard. Computer-assisted surgery (comprising preoperative virtual planning, virtual intraoperative navigation and 3D printing) is a useful tool for this type of surgery. However, we do not know if and how much the final position of the prosthesis differs, in absolute values, from what was planned virtually in the preoperative phase. We propose a comparative result validation system for temporomandibular joint replacement METHODS: In the present study, we propose a comparative validation system using overlapping images, between the model obtained with preoperative virtual planning and the postoperative result. RESULTS: The mean difference for all screws of the glenoid prosthesis was 2.08 mm (range, 1.20-3.03) and for all screws of the condylar prosthesis it was 2.33 mm (range, 1.16-3.56). Mean overall difference between both prostheses in all patients was 2.21 mm (range, 1.16-3.56). CONCLUSIONS: The validation system proposed by overlapping pre- and postoperative images in temporomandibular joint replacement allowed us to establish differences in absolute values between the virtual preoperative model and the actual postoperative result expressed in millimeters.

18F-choline PET/4D CT in hyperparathyroidism: correlation between biochemical data and study parameters. / PET/TC 4D 18F-colina en el hiperparatiroidismo: correlación entre datos bioquímicos y parámetros del estudio.

BACKGROUND: Hyperparathyroidism (HPT) is characterised by increased levels of parathyroid hormone (HPT), surgical excision being the only definitive curative option. After establishing the need for surgery, it is essential to identify the parathyroid glands in the preoperative period to use a minimally invasive approach. Negativity and / or discrepancy in first-line studies (ultrasound and Tc-99m MIBI parathyroid scintigraphy) require more accurate images to reduce the likelihood of bilateral cervical exploration or reintervention. OBJECTIVES: a) To demonstrate the sensitivity of 18F-fluorocholine (18F-choline) positron emission tomography (PET)/4D computed tomography (4D CT) in HPT. b) To check whether there is a correlation between calcaemia and preoperative PTH versus size and early and late SUVmax (Standardized Uptake Value) of the gland, determined by 18F-choline PET/4D CT and c) to study the behaviour of parathyroid lesions with intravenous contrast (IV). MATERIAL AND METHODS: A total of 28 patients were included between 2016 and 2019 in a single institution. Prospective observational cohort study. Correlations were analysed using Pearson's coefficient for variables with normal distribution and Spearman (rho) for those with non-normal distribution. Anatomopathological analysis was the benchmark standard to determine sensitivity was. A p<.05 was interpreted as significant. STATA 13 software was used. RESULTS: Of the 28 patients who underwent 18F-choline PET/4D CT, 18 were operated. Of the 26 lesions diagnosed by 18F-choline PET/4D CT as suggestive of parathyroid lesions, 23 corresponded to glandular disease (adenoma or hyperplasia) establishing a sensitivity of 88.5%. There was a correlation between the patient's preoperative PTH and the maximum size of the gland on 18F-choline PET/4D CT. (Spearman=.66; p=.0014). The parathyroid lesions showed, in addition to IV contrast enhancement, distinctive behavioural characteristics identified as highly suggestive. CONCLUSIONS: 18F-choline PET/CT 4D is an anatomical and functional study with high sensitivity in patients with HPT with negative or discrepant first-line studies. Preoperative PTH showed a correlation with maximum gland size on 18F-choline PET/CT 4D. Parathyroid lesions behave in a highly suggestive way and are enhanced by IV contrast.

Brief guideline for the prevention of COVID-19 infection in head and neck and otolaryngology surgeons.

IMPORTANCE: Anatomically, viral density is greater in the nasal cavity and the nasopharynx. It is to be expected that instrumentation in or through those areas will entail a higher risk of transmission. That's why head and neck and otolaryngologist surgeons are among the most vulnerable health professionals. OBSERVATIONS: Surgeons should essentially perform procedures they require. Surgeries should be performed with personal protective equipment suitable for the high risk of aerosolization: goggles, N95 face mask, facial mask, blood-repelling gown and gloves. It is advisable to have the cooperative COVID-19 test in all patients. Telemedicine is a useful resource if resources allow it. CONCLUSIONS AND RELEVANCE: Otolaryngologists and related specialists are among the groups at higher risk when performing surgeries and upper airway examinations. There are no emergencies in a pandemic. The care of health professionals is crucial to combating this health situation.

Renal clear cell carcinoma metastasis to submandibular gland: case report and review of the literature.

Metastases from renal clear cell carcinoma (RCCC) to the head and neck (HN) region are rare, representing 8-14% of all RCCC metastases, with the thyroid gland being the most common site of RCCC metastasis in the HN. Metastatic tumors that are located in the salivary glands have a prevalence of 5%, while the submandibular gland is only involved in 1% of the cases. We present the case of a 74-year-old female patient with metastasis to the submandibular gland, 11 years after radical nephrectomy for a RCCC.

Reduction of bilateral dislocation of TMJ and Rendu Osler Weber syndrome: case report and physiopathological model.

Temporomandibular joint dislocation (TMJ) is an infrequent clinical situation, representing 3% of all the human body's dislocations. The etiological factors reported are associated to alterations typical of the joint or of the muscular-ligament apparatus, or to clinical conditions that may cause dislocation. We present the case of a 46-year-old patient with hereditary hemorrhagic telangiectasia with bilateral dislocation of the TMJ. There are several potential causes (antipsychotics, intubation, etc.) although the deposit of manganese in the basal ganglia that produce extrapyramidal symptoms could be the most consistent cause.