Imaging of neoplasms of the paranasal sinuses

Guidelines for magnetic resonance imaging in pediatric head and neck pathologies: a multicentre international consensus paper

The use of standardized imaging protocols is paramount in order to facilitate comparable, reproducible images and, consequently, to optimize patient care. Standardized MR protocols are lacking when studying head and neck pathologies in the pediatric population. We propose an international, multicenter consensus paper focused on providing the best combination of acquisition time/technical requirements and image quality. Distinct protocols for different regions of the head and neck and, in some cases, for specific pathologies or clinical indications are recommended. This white paper is endorsed by several international scientific societies and it is the result of discussion, in consensus, among experts in pediatric head and neck imaging.

Sinonasal Diseases Affecting the Orbit - A Radiological Pattern-Based Approach

The orbit is surrounded on three sides by paranasal sinuses with only a thin rim of bone separating the 2 at each site, predisposing it to the risk of being affected by the diseases of primary sinonasal compartment. A wide range of sinonasal pathologies can show orbital involvement and may present mainly with orbital symptoms. While most of these are due to contiguous involvement, a few others may be caused by systemic diseases that often involve both, the orbit and the sinuses in a noncontiguous manner. In this article, we have classified these diseases based on their radiological appearances into 5 patterns: Pattern 1 - Fat stranding predominant, Pattern 2 - Soft tissue without bone destruction, Pattern 3 - Soft tissue with bone destruction, Pattern 4 - Bony pathologies, Pattern 5 - Sinus volume changes. Various pathologies have been classified into these patterns considering the most typical changes in each of the disease processes. We briefly review these patterns, their hallmark radiological signs, typical examples of each pattern as well as review the various diseases process highlighting their radiological appearances. Imaging plays a crucial role in identifying the epicentre of the disease process, narrowing down the differential diagnoses, identifying management modifying complications, planning the surgical management as well as in the follow up of several such lesions. This unique radiological approach, although not absolute, aims to provide a new insight and working algorithm to help narrowing down the differential diagnoses.

Posttreatment surveillance for sinonasal malignancy

PURPOSE OF REVIEW

Sinonasal neoplasms have a high rate of recurrence following treatment, and clinicians utilize a variety of surveillance techniques. Generally, surveillance modality and frequency of follow-up are determined by the guidelines for head and neck cancer as a broad category. However, recent studies have demonstrated that a more tailored approach to follow-up may be necessary.

RECENT FINDINGS

Endoscopy has low sensitivity in recurrence detection, especially in the asymptomatic patient. However, it is able to identify superficial recurrences that may be more amenable to repeat resection. Conversely, imaging [computed tomography (CT), MRI, and F-fluorodeoxyglucose-PET/CT] is useful in ruling out disease, but the inflammatory environment of the posttreatment sinonasal cavity leads to a high number of false positives. This is especially notable in PET/CT, which has worse specificity and positive predictive value in sinonasal malignancy than in head and neck malignancy overall, especially in the early posttreatment period. Little data are available on optimal timing and duration of follow-up, but tumor histology and aggressiveness should be considered when choosing a surveillance approach.

SUMMARY

Sinonasal malignancy surveillance strategies may warrant modifications of current protocols used for head and neck malignancy. This is due to a number of factors, including a greater diversity of sinonasal disorder and increased duration of posttreatment sinonasal inflammation. Clinicians should be aware of the performance parameters of commonly used surveillance techniques and adjust follow-up regimens based on this information.

Imaging Evaluation of the Head and Neck Oncology Patient

Imaging plays a multifaceted role in the diagnosis and characterization of head and neck oncological patients and is integral to their care. Given the complexity of treatment, a multimodality approach is often necessary. With the advent of new technologies, imaging can also be used to predict tumor behavior and treatment response. In this chapter, with selected case examples, we describe the various imaging modalities available and offer suggestions on their utilization.

Optimized imaging of the midface and orbits

A variety of imaging techniques are available for imaging the midface and orbits. This review article describes the different imaging techniques based on the recent literature and discusses their impact on clinical routine imaging. Imaging protocols are presented for different diseases and the different imaging modalities.

Post-treatment Evaluation of Paranasal Sinuses After Treatment of Sinonasal Neoplasms

The aim of imaging in the follow-up of asymptomatic patients treated for sinonasal neoplasms is to detect submucosal relapsing lesions. The challenge is to discriminate recurrent tissue within the changes resulting from unpredictable healing of tissue after surgery and radiotherapy. Scar, inflammation, and recurrence can be better separated with a multisequence MR imaging approach. The choice of the field of view should take into account the risk of in-field intracranial recurrences, craniofacial bone metastases, and perineural spread. Fluorodeoxyglucose-PET has a role in assessing distant metastasis. Its usefulness in local and regional surveillance has yet to be established.

Imaging Approach to Sinonasal Neoplasms

The neoplastic lesions that can be found in the sinonasal space are numerous and varied. This article describes a general approach to narrowing down the differential diagnosis and provides the treating physician sufficient information to choose and deliver the best treatment modality. Computed tomography and MR imaging together provide complete radiologic assessment of sinonasal neoplasms.

Magnetic resonance imaging in sinonasal disease

Computed tomography (CT) is often the primary imaging modality for the evaluation of sinonasal disease. For some indications, magnetic resonance imaging (MRI) may provide additional information. There are established indications for using MRI in complicated sinonasal inflammatory disease, invasive fungal sinus disease, and sinonasal mass lesions. When MRI is used in the evaluation of sinonasal disease, it is usually used as a complementary modality in addition to CT. Magnetic resonance imaging in sinonasal disease can be used to further characterize the primary sinonasal disease process and to evaluate the extent of complications such as orbital or intracranial involvement. When MRI is used in sinonasal disease, it should be evaluated in the context of the clinical situation and CT imaging features. This will help radiologists provide a meaningful differential diagnosis to assist in clinical management.

Imaging and resectability issues of sinonasal tumors

Sinonasal tumors can invade into the critical structures of the anterior and central skull base. Although the determination of precise tumor histology is difficult with imaging, radiology is important in helping differentiate malignant from benign disease. Imaging helps to map the anatomical extent of intracranial and intraorbital tumor, which has important implications for staging, treatment and prognosis. Imaging also helps to facilitate and plan for craniofacial or endoscopic surgical approaches and radiation planning. This paper will review the locoregional invasion patterns for sinonasal tumors, with emphasis on their imaging features. The authors will discuss the implications for staging, resection potential, choice and details of radiotherapy with or without chemotherapy and prognosis. The imaging assessment of structures and compartments that are critical to the skull base team are highlighted: orbit, cavernous sinus, anterior cranial fossa dura/intracranial tumor, lateral frontal sinus, vascular tumor encasement, perineural tumor spread and tumor effect on the surrounding bony structures.

Aggressive inflammatory and neoplastic processes of the paranasal sinuses

Although uncommon, sinonasal malignancies and aggressive inflammatory processes are entities every radiologist will encounter during the evaluation of routine sinus imaging studies. A high index of suspicion is necessary for prompt diagnosis. It is important to consider aggressive inflammatory disease in all patients having routine sinus computed tomography because any delay in diagnosis can adversely affect the patients' care. Magnetic resonance (MR) will often provide a better assessment of the lesion extent, allowing for better surgical treatment. MR is crucial for the accurate assessment of neoplastic lesions. A proficient understanding of the complex anatomy of the region is essential.

Magnetic resonance imaging of sinonasal malignancies

OBJECTIVES

To discuss common sinonasal malignancies with emphasis on squamous cell carcinoma and describe preoperative and postoperative magnetic resonance imaging evaluation for these lesions.

METHODS

Literature and institutional review.

RESULTS

Because of the large variety of the normal cell population, a variety of malignant neoplasms may occur in the sinonasal tract. For a large number of reasons, they are often advanced at the time of diagnosis and are difficult to treat given the complex anatomy of the sinonasal region and its proximity to critical structures. Magnetic resonance imaging is a vital tool in the diagnosis of these lesions and is used in conjunction with computed tomography to precisely delineate the extent of these neoplasms. Involvement of the skull base, the orbits, the intracranial compartment, and potential perineural spread of tumor can influence treatment options. Magnetic resonance is essential to evaluate these tumors.

CONCLUSIONS

Magnetic resonance plays a vital role in the diagnosis of sinonasal neoplasms and is essential to accurately determine the precise extent of these tumors for treatment planning. It is also a useful tool in tumor surveillance.

Primary extraskeletal Ewing's sarcoma of the maxilla with intraorbital extension

Extraskeletal Ewing's sarcoma is often described as a tumour involving the soft tissues of the lower extremities and the paravertebral region. Primary Ewing's sarcoma of the cranium is extremely rare, with only 17 cases reported so far [24]. Involvement of the paranasal sinus is a very rare entity. Involvement of facial bones is characterized by clinical and radiological features distinct from those commonly observed in other sites. Because of the above peculiarities a delay in diagnosis and thus in starting treatment is very probable in such cases. Primary Ewings sarcoma rarely arises in the facial skeleton and only occasionally in the maxilla. To date, there have been 22 cases of maxillary Ewing's sarcoma reported in the English-language literature [25]. We report here a new case of Ewing's sarcoma localized to the maxillary sinus, nose and the orbit, successfully treated by surgery, local high dosage radiotherapy and systemic chemotherapy.

Carcinoma de seio maxilar: análise de dez casos

OBJETIVO: Avaliar o papel, principalmente da tomografia computadorizada, no estadiamento dos carcinomas dos seios maxilares. MATERIAIS E MÉTODOS: Foram analisados dez casos de carcinoma diagnosticados e tratados pelos Departamentos de Diagnóstico por Imagem e Cirurgia de Cabeça e Pescoço do Hospital Heliópolis, São Paulo, SP, entre 1988 e 2002. RESULTADOS: Nove pacientes tiveram extensão tumoral para a bochecha, oito para o espaço mastigador, sete para o assoalho da boca e palato duro, cinco para a fossa pterigóide, cinco para a órbita, três para o etmóide e um para a base do crânio. Três pacientes foram classificados como T3 e sete, como T4. Dois tinham metástases linfonodais no momento da apresentação inicial, os quais pertenciam ao estágio T4. Todos os casos foram confirmados com exame histopatológico. CONCLUSÃO: A análise precisa da extensão local e disseminação tumoral fornecida pela tomografia computadorizada e ressonância magnética desempenha papel importante no planejamento cirúrgico, influenciando, também, na conduta terapêutica e prognóstico.

Three-dimensional visualization of the nasal cavity and paranasal sinuses. Clinical results of a standardized approach using multislice helical computed tomography

OBJECTIVE

The aim of this study was to introduce 3-dimensional (3D) visualization of the nasal cavity and paranasal sinuses as a diagnostic tool and to examination the clinical results of its standardized application.

METHODS

One hundred sixty patients with chronic or acute nasal symptoms underwent helical computed tomography scanning and fiberoptic endoscopy of the sinuses, and 120 of them underwent endoscopic sinus surgery. The 3D images were compared with the axial and multiplanar reconstructed images using a checklist comprising important anatomic landmarks. After qualitative assessment of the representation of anatomic structures in healthy subjects, the method was applied to pathologic cases. The 3D images of these patients were correlated with the preoperative and intraoperative findings.

RESULTS

Six hundred virtual endoscopies (VEs) were performed. The VE views allowed a realistic illustration of the various pathologic findings, except from cases with highly obstructive sinonasal disease. The correlation between the preoperative fiberoptic endoscopy and the intraoperative findings was significant (r = 0.83, P = 0.001).

CONCLUSION

The standardized clinical application of this method serves as an important supplement to 2-dimensional slices and conventional endoscopy.

Imaging in head and neck cancer

The goals of imaging in head and neck cancer are to establish tumor extent and size, to assess nodal disease, to evaluate for perineural tumor spread, and to distinguish recurrent tumor from post-treatment changes. MRI is the preferred modality for assessment of nasopharyngeal, sinonasal, and parotid tumors, because of better contrast resolution, high frequency of perineural spread, and less prominent motion artifacts. MRI is the best modality to delineate the extent of intraorbital and intracranial extension of malignant tumors. Tumors of the oropharynx, larynx, and hypopharynx are frequently primarily imaged with CT, which is less affected by breathing and swallowing artifacts. MRI is also the initial study of choice for tumors confined to the oral tongue, and possibly also for other oral cavity locations because MRI is superior in detection of tumor spread into the bone marrow. There is no clear advantage of CT or MRI for evaluation of nodal disease. Positron emission tomography (PET) is very sensitive for metastatic lymph nodes that are at least 8 mm in size and is the technique of choice in dubious cases. Imaging-guided biopsies are performed whenever needed. For imaging of treated head and neck cancer, PET scans have been found to generally offer higher sensitivity than MRI or CT. Combined PET/CT may be the modality of choice because it almost completely eliminates the false-positive and false-negative PET findings. Patients with head and neck cancer who are referred to tertiary care centers commonly arrive with cross-sectional images obtained at other institutions. Reinterpretation of these studies by dedicated radiologists frequently leads to changes in findings, which alter treatment and affect prognosis.

Malignant melanoma of the nasal cavity

Malignant melanomas of the sinonasal mucosa are very uncommon, presenting frequently in advanced stages with usually a fatal course. Diagnosis becomes more difficult if it is amelanotic variety. Radical surgery is constrained because of increased morbidity & cosmesis, moreover radiotherapy and chemotherapy have little role if any to play. A case of 60 years old male who presented with nasal mass and epistaxis finally diagnosed as melanoma on histolopathology. Some other important aspects of this rare tumor are discussed here.

Primary Ewing's sarcoma of the paranasal sinus with intracranial extension: imaging features

Extraskeletal Ewing's sarcoma is often described as a tumour involving the soft tissues of the lower extremities and the paravertebral region. Involvement of the paranasal sinus is a very rare entity. We present a case of primary Ewing's sarcoma of the paranasal sinus extending into the middle cranial fossa in a 40-year-old female. CT and MRI findings of this unusual case are discussed. To our knowledge, this case is the first to be reported with CT and MRI documentation.