Percutaneous magnetic resonance image-guided biopsy and aspiration in the head and neck

Computed tomography-guided transfacial buccal space core biopsy of deep head and neck space lesions: our experience

Deep head and neck space lesions can present a number of diagnostic challenges due to their deep anatomical position and difficult access for diagnostic tissue sampling. We describe a series of percutaneous 'transfacial' buccal space computed tomography (CT)-guided core biopsies of these lesions and subsequent histological findings. Six patients underwent CT-guided core biopsy of deep parotid, parapharyngeal, or masticator space lesions over a 30-month period. We describe our biopsy technique and correlate our histological findings with subsequent surgical resection where performed. Five of six of CT-guided biopsies obtained sufficient tissue for histological interpretation with varying findings, including salivary gland tumours and squamous cell carcinoma confirmed on subsequent resection. One patient was treated palliatively following core biopsy. No biopsy-related complications were observed. In our small series, percutaneous CT-guided transfacial biopsy via the buccal space has proved an excellent option for the minimally invasive tissue acquisition of deep head and neck space lesions.

Percutaneous Management of Recurrent Head and Neck Cancer: Current Role and Evolving Principles in the Multidisciplinary Setting

PURPOSE OF REVIEW

In this review, we will outline the role of percutaneous interventional radiological management of recurrent head and neck (H&N) cancer in the context of a multidisciplinary setting which consists of surgery, radiation therapy, as well as established and evolving systemic therapies that may impact current practice.

RECENT FINDINGS

Management of recurrent H&N cancer is complex, with attention to the preservation of function and minimal treatment-related morbidity. The favored treatment modalities in local recurrence previously treated with radiotherapy are surgical resection, and if unresectable, for chemotherapy as definitive treatment, or as a prelude to resection if there is good tumor response. Unfortunately, some of these patients are too frail for major surgery or to withstand the toxicity of chemotherapy. There is a gap for effective local therapy without the morbidity of surgery, toxicity of re-irradiation, and systemic side effects of chemotherapy. Percutaneous interventions have the potential to bridge that gap as well as provide palliative symptomatic treatment for patients that have exhausted all treatment options. In the multidisciplinary setting involving the treatment of complex recurrent H&N cancer, percutaneous management now plays a viable and effective role with a foothold in this team-based approach.

MRI-guided biopsy and aspiration in the head and neck: evaluation of 77 patients

OBJECTIVES

To evaluate the efficacy and safety of MRI-guided percutaneous biopsy procedures of head and neck lesions using 0.23T open MRI with optical tracking.

METHODS

A retrospective analysis of 77 patients (51 male, 26 female; mean age, 43 years; range, 11-88 years) who underwent MRI-guided percutaneous biopsy of a head and neck lesion was performed. Mean lesion diameter was 3 cm (range, 1-7.8 cm). Rapid gradient echo sequences were used for image guidance. 23/77 lesions were biopsied after intravenous gadolinium. Tissue sampling techniques included needle aspiration (n = 19) and core needle biopsy (n = 58). Outcome variables included technical success, diagnostic accuracy, procedure time and complications.

RESULTS

In all patients, a sufficient amount of tissue for pathological analysis was obtained. Pathological analysis diagnosed 41 malignant lesions and 36 benign lesions. In 42 cases, surgical correlation was available. In 35 cases, the final diagnosis was confirmed by imaging and clinical follow-up. MR-guided biopsy had a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 93.2%, 100%, 100%, 91.7%, and 96%, respectively. Procedure time was 29 min (range, 15-47 min). No major complications occurred.

CONCLUSIONS

MRI-guided biopsy of head and neck lesions has a high diagnostic performance and is safe in clinical practice.

KEY POINTS

• MRI-guided biopsy helps clinicians to assess patients with head&neck masses. • Differention of malignant and benign lesions is possible with 96% accuracy. • The safety profile of MRI-guided biopsy of head&neck lesions is favorable. • MRI guidance enables accurate biopsy without the use of ionizing radiation.

Approaches for percutaneous needle placement for various head and neck procedures

Use of image-guidance allows safe and precise percutaneous placement of needles for various diagnostic and therapeutic procedures in the head and neck region. This review describes the anatomy relevant to safe-access route planning and the techniques, advantages, and limitations associated with various approaches used for percutaneous needle placement in different head and neck regions. Subzygomatic, retromandibular, paramaxillary, submastoid, transoral, and posterior approaches can be used for percutaneous access in the suprahyoid head and neck region, including skull base and upper cervical vertebrae. In the infrahyoid portion of the neck and for lower cervical vertebrae, access can be achieved via the anterolateral (between the airways and the carotid sheath), posterolateral (posterior to the carotid sheath), and direct posterior approaches.

MR-guided biopsy: a review of current techniques and applications

Biopsy has become a cornerstone of modern medicine and most modern biopsies are performed percutaneously using image guidance, typically computed tomography or ultrasound. MR-guided biopsy offers many advantages over these more traditional modalities, and the recent development of interventional MR imaging techniques has made MR-guided percutaneous biopsies and aspirations a clinical reality. As the field of MR-guided procedures continues to expand and to attract more attention from radiologists, it is important to understand the concepts, techniques, applications, advantages, and limitations of MR-guided biopsy/percutaneous procedures. Radiologists should also recognize the need for their significant involvement in the technical aspects of MR-guided procedures, since several user-defined parameters can alter device visualization in the MR imaging environment and affect procedure safety. This article reviews the prerequisites, systems, and applications of MR-guided biopsy.

Percutaneous Biopsy of Head and Neck Lesions with CT Guidance: Various Approaches and Relevant Anatomic and Technical Considerations

Deep-seated head and neck lesions, which traditionally were evaluated by surgical means, are now accessible with less invasive computed tomography-guided percutaneous needle biopsy techniques. Major vessels, the trachea, and osseous structures like the maxilla, mandible, and vertebrae often preclude direct access to these lesions. It is important to understand the anatomy relevant to safe access route planning and the techniques, advantages, and limitations associated with various approaches used for percutaneous biopsy of head and neck lesions. For biopsy of suprahyoid head and neck lesions, including those of the skull base and upper cervical vertebrae, various approaches such as the subzygomatic, retromandibular, paramaxillary, submastoid, transoral, and posterior approaches can be used. Lesions in the infrahyoid portion of the neck and lower cervical vertebrae can be accessed with the anterolateral approach (between the airways and the carotid sheath), posterolateral approach (posterior to the carotid sheath), and direct posterior approach. The location and extent of the lesions and their relationship to adjacent structures influence the choice of the trajectory to use. Careful planning of the procedure and considerable familiarity with head and neck anatomy are necessary for a biopsy that is both precise and safe.

Percutaneous Biopsy from Blinded to MR Guided: An Update on Current Techniques and Applications

The advent of interventional MR imaging techniques as well as their adoption to guide percutaneous biopsies and aspirations has served as a further step along a series of technical refinements that commenced with the implementation of image-guided approaches for tissue sampling. Nowadays, the practice of and the expectations from these procedures are quite different from those of the blind percutaneous thrusts performed in the late nineteenth and early twentieth centuries. As the field of interventional MR imaging continues to flourish and to attract more radiologists who realize the many opportunities that this technology can offer to their patients, there is a need for a full comprehension of the concepts, techniques, limitations, and cost-effectiveness of MR imaging guidance to present this service to clinical partners in the appropriate setting. Radiologists should also recognize the need for their significant involvement in the technical aspects of MR-guided procedures, because several user-defined parameters and trajectory decisions can alter device visualization in the MR imaging environment and hence affect procedure safety.

The detection of genotoxic activity and the quantitative and qualitative assessment of the consequences of exposures

A wide range of assays are now available which enable the effective detection of the mutagenic (the induction of gene and chromosomal changes) and more generally genotoxic (cellular interactions such as DNA lesion formation) activity of individual chemicals and mixtures. However, when genotoxic activity has been detected and human exposure occurs the critical questions relate to the qualitative and quantitative activity of the agent and the parameters such as routes of exposure, target organs and metabolism. Of major importance in hazard and risk estimation is the nature of the dose response relationship of each chemical and their potential interactions in mixtures. In this paper, we illustrate the methods available to produce quantitative and qualitative data in vitro using the micronucleus assay (as a measure of chromosomal structural and numerical mutations) and the HPRT assay (as a measure of induced gene and point mutations) and the current limitations (such as the large numbers of animals required) for obtaining such information in vivo. We recommend that in vivo studies should primarily focus upon confirmatory mechanistic analysis. For individual chemicals, profiles of the base changes induced can be obtained using the HPRT gene mutation assay and comparisons produced both in vitro and in vivo and thus allow identification of mechanistic differences between different modes of exposure.

Comparison of MR imaging sequences for liver and head and neck interventions

RATIONALE AND OBJECTIVES

To compare the appropriate pulse sequences for interventional device guidance during magnetic resonance (MR) imaging at 0.2 T and to evaluate the dependence of sequence selection on the anatomic region of the procedure.

MATERIALS AND METHODS

Using a C-arm 0.2 T system, four interventional MR sequences were applied in 23 liver cases and during MR-guided neck interventions in 13 patients. The imaging protocol consisted of: multislice turbo spin echo (TSE) T2w, sequential-slice fast imaging with steady precession (FISP), a time-reversed version of FISP (PSIF), and FISP with balanced gradients in all spatial directions (True-FISP) sequences. Vessel conspicuity was rated and contrast-to-noise ratio (CNR) was calculated for each sequence and a differential receiver operating characteristic was performed.

RESULTS

Liver findings were detected in 96% using the TSE sequence. PSIF, FISP, and True-FISP imaging showed lesions in 91%, 61%, and 65%, respectively. The TSE sequence offered the best CNR, followed by PSIF imaging. Differential receiver operating characteristic analysis also rated TSE and PSIF to be the superior sequences. Lesions in the head and neck were detected in all cases by TSE and FISP, in 92% using True-FISP, and in 84% using PSIF. True-FISP offered the best CNR, followed by TSE imaging. Vessels appeared bright on FISP and True-FISP imaging and dark on the other sequences.

CONCLUSION

In interventional MR imaging, no single sequence fits all purposes. Image guidance for interventional MR during liver procedures is best achieved by PSIF or TSE, whereas biopsies in the head and neck are best performed using FISP or True-FISP sequences.

Diagnosis and radiologic manifestations of malignant dumbbell tumors of the parotid gland: review and 2 case reports

Primary malignant dumbbell tumors represent a special growth type of deep-lobe parotid neoplasm. Because they are located in an anatomically limited space between the skull base and the mandibular ramus, they do not cause any but a few nonspecific symptoms and may metastasize into the neck or distant organs before the primary tumor has ever been diagnosed. This article describes 2 cases that first presented as asymptomatic carcinoma unknown primary syndrome and were later discovered to be malignant dumbbell tumors of the parotid gland. Because adequate evaluation is essential for the subsequent management, several diagnostic methods available for the differential diagnosis of this tumor are discussed; we compare these according to their relevance to the therapeutic procedure. Magnetic resonance imaging was found to be the most appropriate imaging technique because of its ability to help us better differentiate between tumor and surrounding tissue. Computed tomography and single photon emission computed tomography can help us identify involvement of the skull base and mandibular ramus.

Magnetic resonance image-guided biopsy and aspiration

Recent advances in magnet design and magnetic resonance (MR) system technology coupled with the development of fast gradient-echo pulse sequences have contributed to the increasing interest in interventional magnetic resonance imaging (MRI). Minimally invasive diagnostic and therapeutic image-based intervention can now be performed under near real-time MR guidance, taking advantage of the high tissue contrast, spatial resolution, vascular conspicuity and multiplanar capabilities of MRI to achieve safe and precise needle placement. This is particularly advantageous for needle navigation in regions of complex anatomy, such as the suprahyoid neck. This article discusses the theoretical concepts and clinical applications of MR for guidance for biopsy and aspiration, and highlights the technical developments that provide the foundation for interventional MRI.