Using Dynamic Maneuvers in the Computed Tomography/Magnetic Resonance Assessment of Lesions of the Head and Neck

Revisiting the "Puffed Cheek" Technique: Advantages, Fallacies, and Potential Solutions

The "puffed cheek" technique is routinely performed during CT neck studies in patients with suspected oral cavity cancers. The insufflation of air within the oral vestibule helps in the detection of small buccal mucosal lesions, with better delineation of lesion origin, depth, and extent of spread. The pitfalls associated with this technique are often underrecognized and poorly understood. They can mimic actual lesions, forfeiting the technique's primary purpose. This review provides an overview of the puffed cheek technique and its associated pitfalls. These pitfalls include pneumoparotid, soft palate elevation that resembles a nasopharyngeal mass, various tongue displacements or distortions that obscure tongue lesions or mimic them, sublingual gland herniation, an apparent exacerbation of the airway edema, vocal cord adduction that hinders glottic evaluation, and false indications of osteochondronecrosis in laryngeal cartilage. Most stem from a common underlying mechanism of unintentional Valsalva maneuver engaged in by the patient while trying to perform a puffed cheek, creating a closed air column under positive pressure with resultant surrounding soft-tissue displacement. These pitfalls can thus be avoided by instructing the patient to maintain continuous nasal breathing while puffing out their cheek during image acquisition, preventing the formation of the closed air column. Keywords: CT, Head/Neck © RSNA, 2024.

Impact of systematic dynamic maneuvers during computed tomography scan on the T classification of head and neck cancers

OBJECTIVES

To evaluate the impact of systematic dynamic maneuvers during CT scan on the T-staging of head and neck cancer (HNC).

MATERIALS AND METHODS

CT scans from the initial workup of 443 consecutive patients treated for HNC in our institution were retrospectively analyzed. CT scans were performed in both expert centers (comprehensive cancer center and university hospital) and non-expert centers. We noted whether dynamic maneuvers (DM) were performed, in 3 categories, namely: DM not done (DMND), done and inadequate (DMDI), done and adequate (DMDA). In the group with DMDA, T-stage was evaluated without and with DM. Interobserver agreement for T staging was assessed after independent double reading of CT scans with and without DM by two radiologists in a random sample.

RESULTS

Among the 443 CT scans, DMND was observed in 36.3%, DMDI in 9.3% and DMDA in 54.4%. DMDA were significantly more frequent in expert than in non-expert centers (93.4 vs 6.6%, p < 0.001). In CT scans with DMDA, analysis of the 141 scans rated as T1, T2, T3, or T4 without DM showed agreement of 88.7% with scans with DM, corresponding to a reclassification rate of 11.3% (kappa = 0.85, 95%CI [0.78;0.92]). Among lesions initially classed as Tx without DM (N = 100), the reclassification rate was 76% including DM.

CONCLUSION

The performance of systematic DM integrated into CT protocols is useful to reclassify the T stage in HNC and is essential in case of lesions initially classified as Tx without DM. DM should be performed routinely in expert and nonexpert centers.

Ultrasonography in the Assessment of Tumors of the Cheek: Water Mouth Distension Technique

PURPOSE

To describe a new B-mode ultrasound examination technique to assess cheek tumors.

MATERIALS AND METHODS

30 cheek oral cavity lesions of different histological types (11 benign and 19 malignant) from 23 patients (11 women and 12 men, 7-82 years old, mean age of 49.5 years) were analyzed. Transcutaneous oral B-mode ultrasound (5-12 MHz transducer) was carried out in two stages. Initially it was performed conventionally with an empty mouth. Next, the patient was asked to keep their oral cavity filled with water (like when using a mouthwash) during imaging for the new test examination technique. The anatomical layers of this region and the characteristics of the tumors were evaluated. Lesions were classified as ill defined, partially defined, or defined. Conventional findings were compared to those of the new technique using the Wilcoxon signed-rank test. Ultrasound results were compared to histological findings analyzed by an independent team.

RESULTS

The conventional empty mouth technique was able to confidently define lesion extension in only 6 of the 30 lesions, while the water-filled mouth technique was able to confidently define lesion extension in 29 of the 30 lesions (p<0.00001).

CONCLUSION

We present a novel technique that dramatically improves ultrasound staging of cheek oral cavity tumors. In addition to the increase in ultrasound accuracy, this technique does not require any special equipment or extra cost, is very well tolerated by patients, and thus should be considered in the evaluation of every patient undergoing transcutaneous cheek ultrasound for oral cavity lesion characterization.

Dynamic manoeuvres on MRI in oral cancers - A pictorial essay

Magnetic resonance imaging has been shown to be a useful tool in the evaluation of oral malignancies because of direct visualization of lesions due to high soft tissue contrast and multiplanar capability. However, small oral cavity tumours pose an imaging challenge due to apposed mucosal surfaces of oral cavity, metallic denture artefacts and submucosal fibrosis. The purpose of this pictorial essay is to show the benefits of pre and post contrast MRI sequences using various dynamic manoeuvres that serve as key sequences in the evaluation of various small oral (buccal mucosa and tongue as well as hard/soft palate) lesions for studying their extent as well as their true anatomic relationship.

Blunt Trauma to the Neck Presenting as Dysphonia and Dysphagia in a Healthy Young Woman; A Rare Case of Traumatic Laryngocele

Laryngocele is not a common clinical entity that presents itself in a trauma setting. In the literature, there are currently two types of laryngocele, internal and mixed. Laryngocele may be congenital or acquired, and most often will present later in life. Traumatic laryngocele has only been reported three times in the literature before. Herein, we report a rare case of a 22-year-old woman who presents with bilateral laryngocele secondary to sustained direct trauma. Neck Ct-scan revealed bilateral laryngocele being responsible for her dysphagia and dysphonia. She was monitored in the hospital for further exacerbation of her symptoms with feared airway occlusion in mind. On hospital day three, her dysphagia had resolved and her dysphonia had significantly improved. A second CT, revealed resolution of left laryngocele with the right decreased in size since the initial presentation. She was followed and had complete resolution of symptoms one week after the injury.

A new CT dynamic maneuver "Mouth Opened with Tongue Extended" can improve the clinical TNM staging of oral cavity and oropharynx squamous cell carcinomas

OBJECTIVES

Cross sectional imaging is mandatory for oral cavity and oropharynx head and neck squamous cell carcinoma's (ooSCC) local extension and TNM staging. However a complex anatomy and frequent dental metallic artifacts make it difficult. This study assesses the clinical benefit of "Mouth Open with Tongue Extended" dynamic maneuver at CT (CTmote) as compared to the conventional CT (CTconv) and MRI.

MATERIAL

Retrospectively, 58 patients with histologically proven ooSCC (oral cavity: 34; oropharynx: 24) were included in the study. All had endoscopy with biopsies, MRI, CTconv and an CTmote acquisitions. Data were splitted in 3 datasets and 2 independent radiologists performed readings blindly. Gold standard was pTNM in 31% of cases; otherwise cTNM obtained at multidisciplinary team meeting with endoscopy and mapping biopsies were used.

RESULTS

CTmote was feasible for all patients including those already treated by surgery or radiotherapy. Exact TNM staging was obtained in 68%, 83%, 83% for CTconv, CTmote and MRI respectively. The best exam ratings at paired wise comparisons were 3%, 47%, 50% for CTconv, CTmote and MRI respectively. CTmote and MRI observer agreements, image quality and confidence ratings, were comparable and higher compared to CTconv (p < 0.001).

CONCLUSIONS

CTmote improves oral cavity and oropharynx tumour stage assessment compared to CTconv with performances close to those of MRI examination. In clinical practice, combining both CT with MOTE maneuver and MRI seems to be the optimal imaging strategy for local staging.

Postprocessing in Maxillofacial Multidetector Computed Tomography

Multidetector computed tomography (CT) and volumetric rendering techniques have always been a useful support for the anatomical and pathological study of the maxillofacial district. Nowadays accessibility to multidetector CT scanners allows the achievement of images with an extremely thin collimation and with high spatial resolution, not only along the axial plane but also along the patient's longitudinal axis. This feature is the main theoretical assumption for multiplanar imaging and for an optimal 3-dimensional postprocessing. Multiplanar reconstruction (MPR) techniques permit images along any plane in the space to be obtained, including curved planes; this feature allows the representation in a single bidimensional image of different anatomical structures that develop on multiple planes. For this reason MPR techniques represent an unavoidable step for the study of traumatic pathology as well as of malformative, neoplastic, and inflammatory pathologies. Among 3-dimensional techniques, Maximum Intensity Projection and Shaded Surface Display are routinely used in clinical practice. In addition, volumetric rendering techniques allow a better efficacy in representing the different tissues of maxillofacial district. Each of these techniques give the radiologist an undoubted support for the diagnosis and the characterization of traumatic and malformative conditions, have a critical utility in the neoplastic evaluation of primary or secondary bone involvement, and are also used in the planning of the most modern radiosurgical treatments. The aim of this article is to define the main technical aspects of imaging postprocessing in maxillofacial CT and to summarize when each technique is indicated, according to the different pathologies of this complex anatomical district.

Diagnostic approach to retromolar trigone cancer by multiplanar computed tomography reconstructions

Neoplasms of retromolar trigone have important peculiarities due to their spatial relationships with the surrounding structures. Tumours that involve this area can extend to nearby muscles; adipose spaces; and other anatomic structures, such as the soft palate, the tonsillar fossa, the parapharyngeal space, and the floor of the mouth. In spite of a relatively quick diagnosis, the real extent of these tumours is typically underestimated at clinical examination. Our purpose was to propose a systematic approach to the use of multiplanar computed tomography reconstructions to evaluate normal retromolar trigone anatomy and the main pathways of spread for tumours that arise in this area. To our knowledge, only few reports exist in literature about this topic and none are about the usefulness of multidetector computed tomography and multiplanar reconstructions.