Search PubMed⌕ Search

Biomedical subjects

H D Curtin

Publications and source records attributed to H D Curtin.

At least 19 recordsLinked to original sources
PubMed1997

A re-evaluation of imaging criteria to assess aggressive masticator space tumors.

PURPOSE: To evaluate the correlation between the gross imaging evidence of an aggressive masticator space (MS) tumor and the presence of such a MS malignancy. MATERIALS AND METHODS: Thirty patients were identified retrospectively who had a malignancy that either arose in or metastasized to the MS, had pathologic verification of the diagnosis, and had magnetic resonance (MR) and/or computed tomographic (CT) images. Specifically evaluated was the presence or absence of gross imaging evidence of mandibular erosion and the integrity of the medial MS fascia as evaluated by a smooth margin between this fascia and the parapharyngeal space fat. RESULTS: Of the 30 tumors, 28 were high-grade malignancies and 2 were histiocytoses. Of these, 5 had mandibular erosion and violation of the MS fascia, 19 had bone erosion with an intact fascia, 4 had neither bone erosion nor fascial violation (3 of these patients were under the age of 20 years), and 2 had fascial violation with no bone erosion. CONCLUSIONS: In 76.7% of patients with a malignancy arising in the MS, on imaging the medial MS fascia was grossly intact. There were 4 patients with MS malignancy and neither violation of the medial MS fascia nor mandibular bone erosion. Thus, these imaging findings may not be good criteria to evaluate the presence of a high-grade MS malignancy, especially if the patient is under the age of 20 years, in which age group MS sarcomas are more likely to arise.

Adolescent↗
PubMed1996

Chondrosarcoma of the nasal septum: skull base imaging and clinicopathologic correlation.

Chondrosarcoma arising in the head and neck and craniofacial region is an uncommon lesion. The nasal septum is a particularly rare site of origin, with approximately 30 cases previously reported in the English literature. We present six new cases of chondrosarcoma arising in the nasal septum. Each of these tumors required cranial base surgical approaches for removal. Current imaging techniques allow a very accurate diagnosis to be made before biopsy. The characteristic ring-forming calcifications seen on computed tomography scans can be correlated with the histologic pattern of calcification. Magnetic resonance imaging techniques allow precise definition of tumor extent, which is particularly important because the disease is best treated with primary surgery. Advances in imaging and surgical techniques allow a much more complete tumor removal. It is hoped that this will increase the likelihood of cure in these patients. Surgical management and indications for adjuvant therapy are discussed.

Adult↗
PubMed1996

T2-weighted MR characteristics of internal auditory canal masses.

PURPOSE: To determine whether masses of the internal auditory canal are hypointense relative to cerebrospinal fluid, and therefore visible, on fast spin-echo T2-weighted MR images. METHODS: Forty-six patients had 50 masses of the internal auditory canal, identified initially on contrast-enhanced MR images, that were evaluated retrospectively for signal intensity of the mass with respect to cerebrospinal fluid and for visibility of the neural elements within the internal auditory canal on T2-weighted images. RESULTS: Forty-seven of 50 masses were clearly identified on T2-weighted images. Three small abnormalities (2 to 4 mm) were not seen with confidence on T2-weighted images. However, on close inspection of these three masses, the small abnormality on contrast-enhanced MR images corresponded to a hypointense focus on T2-weighted images. All 50 masses were hypointense relative to cerebrospinal fluid on T2-weighted images. CONCLUSION: All masses of the internal auditory canal in this study were hypointense relative to cerebrospinal fluid on T-2 weighted images, and were therefore visible.

Cohort Studies↗
PubMed1995

Necrotizing (malignant) external otitis: prospective comparison of CT and MR imaging in diagnosis and follow-up.

PURPOSE: To compare computed tomography (CT) and magnetic resonance (MR) imaging in the diagnosis and follow-up of necrotizing external otitis. MATERIALS AND METHODS: CT and MR imaging were performed in seven patients at diagnosis and at 6 and 12 months after initiation of therapy. Imaging findings were compared and correlated with the clinical course of the disease. RESULTS: Cortical bone erosion was best seen on CT scans (n = 5 vs n = 0 on MR images) and failed to normalize with cure. Subtemporal soft-tissue abnormalities (n = 7 with both modalities) were better appreciated with MR imaging and had low signal intensity on T1- and T2-weighted images. Soft-tissue changes improved but did not disappear completely with treatment. CONCLUSION: CT is preferred at initial diagnosis, as small cortical erosions are better seen. Either modality can be used to follow up soft-tissue evolution. MR imaging may be better for evaluation and follow-up of meningeal enhancement and changes within the osseous medullary cavity.

Aged↗
PubMed1995

Enlarged anterior chamber: CT finding of a ruptured globe.

A deep anterior chamber of the globe is a clinical sign of posterior scleral rupture, an ophthalmologic emergency. On axial CT, the depth of the anterior chambers of ruptured globes was greater than the depth of the anterior chambers of normal globes. The discrepancy between the depth of the two anterior chambers in any patient can also suggest posterior scleral rupture.

Anterior Chamber↗
PubMed1995

The petrous apex.

Petrous apex lesions are rare, but when present, they can usually be precisely defined. The key to their identity consists of answering five questions: 1) Is the abnormality arising in the petrous apex or from contiguous areas? 2) Are the bony walls of the apex and the septations in the air cells smoothly remodeled? 3) What are the MR imaging signal characteristics of the lesion? 4) Is there enhancement of the internal "matrix" of the lesion? 5) What is the relationship of the lesion to the carotid artery?

Brain Neoplasms↗
PubMed1995

Lesions of the parapharyngeal space. Role of MR imaging.

Because the parapharyngeal space is one of the deep spaces of the upper neck, it is a difficult region to examine clinically. On each side of the head, this space is located lateral to the pharynx and medial to the ramus of the mandible, the pterygoid muscles, and the parotid gland. It is only with bimanual palpation that any small fullness within this space may be clinically appreciated. When a parapharyngeal mass is sufficiently large, it displaces the lateral pharyngeal wall and pharyngeal tonsil toward the midline and may cause lateral displacement of the parotid gland. Only when a lesion is very large does it manifest as a fullness near the angle of the mandible. Thus, clinical evaluation of the space is quite limited.

Humans↗
PubMed1994

Advances in treatment of tumors of the cranial base. Advances in imaging.

Imaging has facilitated aggressive skull base surgery by allowing precise preoperative delineation of the extent of lesions. Continued advances providing even better resolution on imaging studies may in turn facilitate the development of new surgical approaches to the skull base.

Adipose Tissue↗
PubMed1994

Cranial base surgery: results in 183 patients.

OBJECTIVE: To learn about the effects of cranial base surgery. DESIGN: Cohort study with a mean follow-up of 30 months. SETTING: Population-based. PATIENTS: A consecutive sample of 183 patients who underwent cranial base surgery; 118 patients had malignant skull base tumors, the majority of which were previously treated; 50 had benign tumors; 9 had congenital malformations of the skull base; 3 had inflammatory lesions, and 3 had traumatic defects of the skull base. MAIN OUTCOME MEASURES: Disease-free interval, overall survival, and rate of complications and functional status. INTERVENTION: Cranial base surgery was followed by radiotherapy (in previously untreated patients). RESULTS: After completion of follow-up (mean, 30 months), 30 (25.4%) patients had died of their malignant tumors and 8 (6.8%) had died of other causes. One patient (0.84%) was lost to follow-up. The overall cancer survival rate without regard to histologic type was 67% (63% with no evidence of disease). Among the patients who were treated for benign neoplasm, 72% had no evidence of disease at a mean follow-up of 39 months. The group of patients with congenital malformations and inflammatory and traumatic lesions demonstrated successful correction of their presurgical problem with skull base surgery. One patient (who had invasive aspergillosis) died of disease. The overall surgical-medical mortality rate was 2%; the complication rate was 33%, and the Karnofsky performance score was improved or unchanged after surgery in 83% of patients. The average duration of surgery, number of blood transfusions used, and length of the hospital stay were 10 hours, 3 units, and 15 days, respectively. CONCLUSIONS: Cranial base surgery is a valid surgical technique for treatment of cranial base afflictions. In this study it was found to be beneficial in controlling benign and malignant disease and to be the treatment of choice for selected congenital malformations, trauma, and inflammatory lesions.

Adolescent↗
PubMed1994

Imaging of ossicular prostheses.

The prostheses available for reconstruction of the ossicular chain have expanded to include a variety of synthetic materials. Hydroxyapatite contains the inorganic constituents found in human living bone and is currently being incorporated into many new prostheses. This study demonstrates the computed tomography and magnetic resonance image characteristics of eight middle ear prostheses, a block of dense hydroxyapatite, and a human incus. Imaging of ossicular prostheses is more informative with computed tomography.

Bone Substitutes↗
PubMed1994

Inflammatory lesions and tumors of the nasal cavities and paranasal sinuses with skull base involvement.

The size and location of these masses can be accurately assessed today with appropriate imaging studies. The radiologist, however, must pay attention to detail and carefully evaluate the margins of the lesion and note its precise size because this information determines the operation and operative approach used. In addition, by carefully analyzing the imaging characteristics, a fairly accurate preoperative diagnosis can be given that will allow treatment planning to precede until final pathologic confirmation is available.

Bone Diseases↗
PubMed1994

Double mucocele of the paranasal sinuses.

We have observed two contiguous mucoceles in one patient. Based on the mucoceles' signal intensities on MR imaging, as well as their anatomic location as delineated by CT and MR, we hypothesize that the "downstream" mucocele obstructed the "upstream" sinus, leading to formation of a secondary mucocele.

Adult↗
PubMed1994

Fast spin-echo imaging of the neck: comparison with conventional spin-echo, utility of fat suppression, and evaluation of tissue contrast characteristics.

PURPOSE: To determine whether fast spin-echo sequences could replace conventional spin-echo methods in the evaluation of head and neck neoplasms and associated adenopathy and to evaluate differences in tissue contrast characteristics between conventional spin-echo and fast spin-echo examinations of head and neck disease. METHODS: Twenty-seven patients with squamous cell carcinoma were imaged on a 1.5-T imager with both conventional spin-echo and fast spin-echo sequences with identical section thickness and position. Twenty-one of the 27 fast spin-echo studies were performed with frequency-selective fat suppression. Three radiologists independently evaluated the images using a five-point scale to compare primary lesion margin definition and conspicuity, lymph node margin definition and conspicuity, gross motion artifact, and flow artifact. Quantitative percent contrast and contrast-to-noise ratios were calculated and compared in 7 cases with fat-suppressed fast spin-echo. RESULTS: Fast spin-echo was preferred by all three readers for lesion margin conspicuity and lymph node conspicuity. Gross motion and flow artifact demonstrated trends toward reader preference for fast spin-echo. Quantitative contrast values for fast spin-echo were significantly greater than those for conventional spin-echo. CONCLUSIONS: Fast spin-echo with fat suppression can replace conventional spin-echo at a time savings of more than 50% and improves tissue contrast and the conspicuity and definition of margins for primary lesions and lymph nodes. Fat-suppression heterogeneity remains the major limitation of this technique. Thus, careful attention to fat-suppression failure and unwanted water saturation is essential.

Adipose Tissue↗