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J A Castelijns

Publications and source records attributed to J A Castelijns.

At least 73 records · Page 4Linked to original sources
PubMed1995

Review of artifacts associated with transrectal ultrasound: understanding, recognition, and prevention of misinterpretation.

Artifacts are inadequate representations of the structures being imaged. Transrectal ultrasound (TRUS) used for evaluating rectal tumors has its own, unique spectrum of artifacts such as (1) pseudomasses (beam thickness: imaging of rectal folds; mirror image: reflection at an intraluminal fluid level); (2) inadequate size of the lesion (mirror image or grating lobes); (3) simulation of malignant infiltration (beam thickness, attenuation or refraction); (4) incomplete field of view (shadowing; reverberation or mirror-image); (5) confusing echo patterns (side lobe artifacts or mirror image: reflection at the balloon surface). The understanding of the physical properties of ultrasound is the basis for the recognition of these artifacts and prevention of misinterpretation. We present a review of these artifacts and their causes.

Artifacts↗
PubMed1995

The value of magnetic resonance imaging in the differential diagnosis of parapharyngeal space tumours.

Between 1987 and 1993 14 patients with a parapharyngeal space tumour were imaged by magnetic resonance imaging (MRI). The vagal body tumours, presenting in the poststyloid compartment, all showed flow voids with anterior and medial displacement of the internal carotid artery. None of the salivary gland tumours, all presenting in the prestyloid compartment with posterior displacement of the internal carotid artery, showed flow voids. MRI is superior compared with other modalities in evaluating the differential diagnosis, especially regarding vascular vs non-vascular tumours. It should encompass T1 SE images to assess the presence or absence of flow voids. In vascular tumours angiography must be used to assess feeding vessels, multiplicity, and sides involved. T1 GE images are useful as they allow superior identification of the internal carotid artery and its relation with the tumour accordingly. In addition to T1 SE images, T2 SE images may help in the evaluation of the differential diagnosis. In all non-vascular tumours aspiration cytology is required to differentiate between benign and malignant disease.

Adenocarcinoma↗
PubMed1995

Predictive value of MR imaging-dependent and non-MR imaging-dependent parameters for recurrence of laryngeal cancer after radiation therapy.

PURPOSE: To determine the predictive value of several clinical and radiologic parameters for recurrence of laryngeal cancer. MATERIALS AND METHODS: Eighty previously untreated patients underwent magnetic resonance (MR) imaging before radiation therapy with curative intent. Tumor volume was calculated from T1-weighted MR images. Cartilage was considered invaded by pathologic tissue if it had intermediate signal intensity on T1-weighted spin-echo (SE) MR images and high signal intensity on T2-weighted SE MR images. The minimum follow-up was 2 years. RESULTS: Parameters such as age, sex, histopathologic findings, and invasion of the vocal muscle or pre-epiglottic space were not significantly correlated with tumor recurrence. Logistic regression analysis showed three relevant contributors: cord mobility, as judged clinically, and tumor volume and, more significantly, cartilage invasion, as seen at MR imaging. CONCLUSION: For untreated laryngeal cancer, MR imaging findings of tumor volume and cartilage invasion allow better patient selection for either radiation therapy or surgery. MR imaging is mandatory for T staging of laryngeal cancer.

Adult↗
PubMed1993

Modern imaging techniques and ultrasound-guided aspiration cytology for the assessment of neck node metastases: a prospective comparative study.

Although palpation has proved to be an unreliable staging procedure, the indications for and the implications of more reliable radiologic staging methods for the neck in patients with a primary squamous cell carcinoma of the head and neck remain controversial. Only a very accurate imaging technique can replace neck dissection in clinical NO disease. This study compares the value of palpation with computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound (US) with or without guided aspiration cytology for neck node staging. One hundred and thirty-two patients with squamous cell carcinoma of the head and neck were examined radiologically before undergoing a total of 180 neck dissections as part of their treatment. CT, US and MRI proved to be significantly more accurate than palpation for cervical lymph node staging. The accuracy of US-guided aspiration cytology was significantly better than of any other technique used in this study. Modern imaging techniques are essential for appropriate assessment of neck node metastases. In view of advances in the accuracy of contemporary imaging, the need for elective treatment of the neck requires reappraisal.

Biopsy, Needle↗
PubMed1993

Magnetic resonance imaging evaluation of extracranial head and neck tumors.

The introduction first of computed tomography (CT) and then in the 1980s of magnetic resonance imaging (MRI) has resulted in numerous applications of these imaging methods to head and neck oncology. MR imaging is a rapidly evolving field, which is replacing CT in the majority of lesions of the extracranial head and neck: tumors of the skull base, paranasal sinuses, nasopharynx, parapharyngeal space, and carcinomas of the oral cavity, pharynx, and larynx. MR imaging is the method of choice for the detection and staging of skull base lesions because of its superior sensitivity in detecting small lesions and its superior accuracy in staging the lesion and narrowing the diagnostic possibilities. MRI shows the extent of tumor in the paranasal sinuses more precisely, and by multiplanar imaging it outlines intracranial extension. MR imaging has greater accuracy than CT in differentiating parapharyngeal lesions and can detail the extent of tumor tissue in squamous cell carcinoma of the oral cavity, pharynx, and the larynx more accurately. It is more sensitive than CT in showing invasion by tumor tissue into the mandible or laryngeal cartilages.

Carcinoma, Squamous Cell↗
PubMed1992

Radioimmunoscintigraphy of head and neck cancer using 99mTc-labeled monoclonal antibody E48 F(ab')2.

The diagnostic value of 99mTc-labeled monoclonal antibody E48 F(ab')2 (750 MBq, 1 mg) was evaluated in 10 patients with a histologically proven squamous cell carcinoma of the head and neck and with clinical evidence of cervical lymph node involvement. Preoperative findings on lymph node status obtained by radioimmunoscintigraphy (RIS), computerized tomography, magnetic resonance imaging, and palpation were defined per side (left and/or right side of the neck) as well as per lymph node level (I through V) and compared with the histopathological outcome of the neck dissection specimen. In 10 patients, all 8 known tumors at the primary site were detected by RIS. Furthermore, RIS was correct in 13 of 13 tumor involved neck sides and in 17 of 20 tumor involved lymph node levels. False-negative observations comprised 3 levels containing tumor deposits smaller than 1 cm in diameter, 2 of which were not detected by any other diagnostic modality. Palpation, computerized tomography, and magnetic resonance imaging were correct in, respectively, 13, 15, and 15 of the 20 tumor involved levels. There were 2 false-positive observations with monoclonal antibody E48 and 3 with palpation. No false-positive detections occurred with computerized tomography or magnetic resonance imaging. In two of the patients, RIS provided clinically important information which was not provided by any other diagnostic method. In one patient, recurrence of laryngeal carcinoma was established at the primary site after previous radiotherapy. In another patient, bilateral instead of unilateral lymph node involvement became apparent. These preliminary data indicate that radioimmunoscintigraphy with monoclonal antibody E48 may be helpful in the diagnosis of metastatic and recurrent head and neck cancer.

Adolescent↗
PubMed1991

Magnetic resonance imaging vs palpation of cervical lymph node metastasis.

In a series of 100 patients with head and neck carcinoma, the preoperative histopathologic findings of palpation and magnetic resonance imaging were compared with regard to both laterality and lymph node level (I through V). The overall error for palpation in detecting affected sides was 32%. Gadolinium-enhanced magnetic resonance images reliably upgraded 60% of the clinically negative necks, the overall error of magnetic resonance imaging being 16%. However, for both modalities, the sensitivity per level was too low to allow for selective neck dissections in case of only one positive level. These findings show that apart from primary tumor grading, magnetic resonance imaging can improve the preoperative grading of cervical lymph nodes. In selected cases, this may change the treatment plan to a "wait-and-see" policy or a more conservative type of neck dissection.

Aged↗
PubMed1991

Lymph node staging in patients with clinically negative neck examinations by ultrasound and ultrasound-guided aspiration cytology.

To assess the usefulness of ultrasound and ultrasound-guided fine-needle aspiration cytology in detecting occult cervical lymph node metastases, 107 patients with squamous cell carcinoma of the head and neck, who underwent 132 elective neck dissections, had preoperative ultrasound examination. During the assessment of the last 54 patients, who underwent 70 elective neck dissections, ultrasound-guided aspiration cytology was available. Although ultrasound was able to detect lymph node metastases in the majority of patients, the accuracy of this technique never exceeded 70% (93 of 132 procedures). With ultrasound-guided aspiration cytology, accuracy was 89% (62 of 70 procedures). This latter technique seems to be the modality of choice for the assessment of the clinically negative neck. Its use obviates the need for elective neck dissection, done because of the high risk of occult metastasis.

Biopsy, Needle↗
PubMed1991

Diagnostic radiology of head and neck oncology.

The rapid development of computed tomography and magnetic resonance imaging has resulted in numerous applications of these modalities in head and neck oncology. In the past year further refinements in diagnostic capabilities have been obtained in magnetic resonance imaging. Computed tomography is rapidly being replaced by magnetic resonance imaging as the study of choice in the majority of lesions in the larynx, pharynx, tongue, paranasal sinuses, and parapharyngeal space. Magnetic resonance imaging, ultrasound-guided fine-needle aspiration cytology, and in potential radioimmunolocalization of cancer deposits by monoclonal antibodies have great value for the detection of lymph node metastasis in the neck. Because more effective locoregional treatment has been developed, there is an increasing interest in the early diagnosis of distant metastases. The value of new technologies such as three-dimensional imaging and spectroscopy for imaging of primary tumors must be assessed.

Head and Neck Neoplasms↗
PubMed1991

Occult metastatic neck disease: detection with US and US-guided fine-needle aspiration cytology.

The authors performed a prospective study of the value of ultrasonography (US) and US-guided fine-needle aspiration cytology (FNAC) for assessment of N0 lesions in the neck. Preoperative US was performed in 107 patients with squamous cell carcinoma of the head and neck, who underwent 132 elective neck dissections. During the US examination of the last 54 patients, who underwent 70 elective neck dissections, US-guided FNAC was performed. US alone was found to be an unreliable method for detecting occult lymph node metastasis; the accuracy never exceeded 70% (93 of 132), with a sensitivity of 60% (32 of 53) and a specificity of 77% (61 of 79). In contrast, US-guided FNAC had an accuracy of 89% (62 of 70), a sensitivity of 76% (25 of 33), and a specificity of 100% (37 of 37). Because of the high sensitivity and specificity of US-guided FNAC for the assessment of the N0 neck, this modality may play an important role in directing treatment of these patients in the future.

Biopsy, Needle↗
PubMed1990

MR findings of cartilage invasion by laryngeal cancer: value in predicting outcome of radiation therapy.

Thirty-nine patients who underwent radiation therapy with curative intent for laryngeal cancer were examined before treatment with magnetic resonance (MR) imaging, between November 1985 and January 1987. MR findings of cartilage invasion were correlated with the effectiveness of radiation treatment. Adequate interpretation of the MR examinations was not possible in four cases (10%). Cartilage invasion was found in 16 of the 35 remaining patients and was found even in small glottic lesions, clinically staged as T1b and T2. Laryngeal cancer recurred in 10 of the 16 patients with cartilage invasion shown by MR imaging. The presence of even small foci of invasion of the thyroid cartilage by laryngeal cancer appeared to increase the subsequent risk of tumor recurrence. Cartilage invasion seen at MR imaging might therefore shift the preference to partial laryngectomy as the initial treatment for small glottic tumors. Alternatively, radiation therapy alone would appear to require stringent follow-up to detect possible recurrence.

Adult↗
PubMed1990

Cervical lymph node metastasis: assessment of radiologic criteria.

To estimate the accuracy of different radiologic criteria used to detect cervical lymph node metastasis in patients with head and neck carcinoma, seven different characteristics of 2,719 lymph nodes in 71 neck dissection specimens from 55 patients were assessed. Three lymph node diameters, their location, their number, the presence of a tumor, and the amount of necrosis and fatty metaplasia were recorded. The minimal diameter in the axial plane was found to be the most accurate size criterion for predicting lymph node metastasis. A minimal axial diameter of 10 mm was determined to be the most effective size criterion. The size criterion for lymph nodes in the subdigastric region was 1 mm larger (11 mm). Groups of three or more borderline nodes were proved to increase the sensitivity but did not significantly decrease the specificity. Radiologically detectable necrosis (3 mm or larger) was found only in tumorous nodes and was present in 74% of the positive neck dissection specimens. Shape was not a valuable criterion for the radiologic assessment of the cervical lymph node status.

Carcinoma, Squamous Cell↗
PubMed1989

[Diagnosis of laryngeal carcinoma using proton spin resonance tomography].

Seventy-eight patients were investigated by magnetic resonance (MR) imaging using optimal scan parameters and a surface coil. Forty-two patients were also examined by computer tomography (CT). Sixteen patients underwent laryngectomy. MR imaging of cancerous tissue in the larynx, and particularly of non-invaded and invaded cartilages, was examined by comparing MR images with sliced surgical specimens. Pre-operative CT and MRI findings were evaluated by comparing them with postoperative histopathological findings. MR T1-weighted images demonstrate localisation and extent of cancerous tissue. With combined use of T1-weighted and proton-density images MR imaging is superior to CT for showing cartilage invasion. Unfortunately, gross movement artifacts, which resulted in non-diagnostic images, occurred in 16% of the examinations.

Aged↗