PubMed Health⌕ Search

Biomedical subjects

Peter M Som

Publications and source records attributed to Peter M Som.

16 recordsLinked to original sources

Role of 3D CT in the evaluation of the temporal bone.

In recent years, three-dimensional (3D) multiplanar reformatted images from conventional cross-sectional computed tomographic (CT) data have been increasingly used to better demonstrate the anatomy and pathologic conditions of various organ systems. Three-dimensional volume-rendered (VR) CT images can aid in understanding the temporal bone, a region of complex anatomy containing multiple small structures within a relatively compact area, which makes evaluation of this region difficult. These images can be rotated in space and dissected in any plane, allowing assessment of the morphologic features of individual structures, including the small ossicles of the middle ear and the intricate components of the inner ear. The use of submillimeter two-dimensional reconstruction from CT data in addition to 3D reformation allows depiction of microanatomic structures such as the osseous spiral lamina and hamulus. Furthermore, 3D VR CT images can be used to evaluate various conditions of the temporal bone, including congenital malformations, vascular anomalies, inflammatory or neoplastic conditions, and trauma. The additional information provided by 3D reformatted images allows a better understanding of temporal bone anatomy and improves the ability to evaluate related disease, thereby helping to optimize surgical planning.

Bone Diseases↗

Necrotic nasopharyngeal mucosa: an ominous MR sign of a carotid artery pseudoaneurysm.

Massive hemoptysis is not commonly seen in patients who have nasopharyngeal carcinoma. It most often is the result of both radiation therapy and skull base infection. We present a practical imaging approach by using MR imaging and conventional angiography that may facilitate the prevention of such life-threatening bleeding and help provide effective control of infection. With the aid of these studies, clinicians may be able to manage this condition with more confidence.

Carotid-Cavernous Sinus Fistula↗

Cavernous carotid aneurysm presenting with epistaxis.

BACKGROUND: Carotid artery aneurysms are a rare cause of epistaxis. The most common presentation for nontraumatic cavernous internal carotid artery aneurysms is mass effect, with only 3% presenting with hemorrhage. We present a case of epistaxis caused by a nontraumatic cavernous internal carotid artery aneurysm. METHODS: A 73-year-old white woman was seen with a 1-month history of recurrent right-sided epistaxis. The patient had essential hypertension and a family history of intracranial aneurysm. A complete otolaryngologic, neurologic, and ophthalmologic examinations were normal. Contrast-enhanced CT of the paranasal sinuses revealed a trilobed aneurysm of the cavernous segment of the right internal carotid artery. Coil embolization of the cavernous aneurysm and right internal artery was performed. RESULTS: The patient has had no further episodes of epistaxis and has remained neurologically intact. CONCLUSION: Carotid artery aneurysms must be considered in the differential diagnosis of profuse epistaxis.

Aged↗

Amyloidosis concurrently involving the sinonasal cavities and larynx.

Localized amyloidosis is an uncommon benign disorder. The purpose of this report is to present the case of a 21-year-old man who had localized amyloidosis simultaneously involving the sinonasal cavities and the larynx. The rarer sinonasal lesion demonstrated CT findings of adjacent "fluffy" bone changes, possibly representing a new finding suggestive of this disorder. At MR imaging, the amyloid had signal intensity similar to that of skeletal muscle on T1- and T2-weighted images. After contrast material administration, the amyloid enhanced at most minimally, but peripheral enhancement about the mass was present. The importance of this case lies in the multifocal presentation of this uncommon disorder, and the imaging findings herein may provide a new sign of this paranasal sinus disease.

Adult↗

The incidence of concha bullosa and its relationship to nasal septal deviation and paranasal sinus disease.

BACKGROUND AND PURPOSE: The incidence of middle turbinate pneumatization, or concha bullosa, has been well described in the literature. However, to our knowledge, no study has evaluated concha bullosa in relation to nasal septal deviation. We sought to analyze the incidence of concha bullosa and any correlation with nasal septal deviation and paranasal sinus disease. METHODS: Three neuroradiologists retrospectively reviewed findings of 1095 consecutive paranasal sinus CT studies conducted between 2001 and 2002. All examinations were performed for evaluation of a symptom referable to the sinonasal region. Paranasal sinus inflammatory disease was identified and graded as mild, moderate, or severe. Sphenoid, ethmoid, maxillary, and frontal sinuses were each graded separately on both sides. If a concha bullosa was present, it was graded in size as small, moderate, or large. If bilateral concha were present, sizes were compared and when one was larger, it was identified as dominant. When nasal septal deviation was present, it was graded as mild, moderate, or severe. The direction of nasal septal deviation was identified as the face of the convex surface. RESULTS: There was a clear association between the presence of a unilateral concha, or a dominant concha (in the case of bilateral concha), and the presence of nasal septal deviation (P < .0001). Moreover, there was a significant relationship between the presence of concha bullosa and deviation of the nasal septal to the contralateral side (P < .0001). This inverse association was present regardless of the size of the concha bullosa or degree of septal deviation. In every case, there was some preservation of air channels between the dominant concha and the nasal septum. Seventy-three percent of patients with concha bullosa had paranasal sinus inflammatory disease; 78% of patients without concha bullosa also had some form of inflammatory disease. CONCLUSION: Concha bullosa is a common anatomic variant. There is a strong association between the presence of a concha bullosa and contralateral deviation of the nasal septum. Nasal septal deviation away from the dominant concha, with preserved adjacent air channels, suggests that the deviation is not a direct result of mass effect from the concha. No increased incidence of paranasal sinus disease exists in patients with concha bullosa.

Adolescent↗

Spread of goiters outside the thyroid bed: a review of 190 cases and an analysis of the incidence of the various extensions.

OBJECTIVES: To analyze the distribution of thyroid goiters into the mediastinum and/or behind or along the sides of the pharynx, and to review the anatomy of the spaces in the neck that explains these extensions. METHODS: We used a 28-month period, to retrospectively identify 190 cases of neck goiters that underwent computed tomographic imaging. The maximal size of a normal thyroid gland and the limits of the normal thyroid bed were defined on the basis of established anatomic measurements. Standard definitions of the mediastinum and its compartments were also used. Each case was reviewed by 3 radiologists, and extension of the thyroid gland into the mediastinum or cranially behind or along the sides of the pharynx was noted. All cases were correlated with clinical observations. RESULTS: Of the 190 goiters, 106 (55.8%) were confined to the thyroid bed, 70 (36.8%) extended into the mediastinum, and 14 (7.4%) extended behind or along the sides of the pharynx. All 70 cases that extended into the mediastinum involved the anterior mediastinum, and 5 (7.1%) of these extended into the posterior mediastinum. CONCLUSIONS: Goiterous extension outside of the thyroid bed occurred in 84 (44.2%) of cases. Although extension cranially behind the pharynx is uncommon, the physician should be aware of this diagnosis and the fascial anatomy that explains its occurrence. All of the goiters that were in the posterior mediastinum also had a component in the anterior mediastinum.

Adult↗

Evaluation of neck and body metastases to nodes with ferumoxtran 10-enhanced MR imaging: phase III safety and efficacy study.

PURPOSE: To determine the safety and efficacy of ferumoxtran 10-enhanced magnetic resonance (MR) imaging for diagnosis of metastases to lymph nodes and the clinical usefulness of ferumoxtran 10 in nodal staging. MATERIALS AND METHODS: One hundred fifty-two patients were injected with ferumoxtran 10. Readers independently evaluated precontrast MR images by using node size criteria and subjective assessment of other imaging features. Ferumoxtran 10-enhanced MR images were evaluated alone and paired with precontrast images for comparison. The diagnostic performances of precontrast MR size criteria and postcontrast MR imaging were evaluated with receiver operating characteristic (ROC) analysis. Lymph node signal intensity was correlated with histopathologic findings. MR imaging and histopathologic nodal stages were compared. RESULTS: Node-level sensitivity, specificity, and accuracy of precontrast MR imaging were 54%, 82%, and 68%, respectively, with node size criterion alone; 91%, 51%, and 71%, respectively, with subjective reader assessment; 85%, 85%, and 85%, respectively, with postcontrast MR imaging alone; and 83%, 77%, and 80%, respectively, with paired pre- and postcontrast MR imaging. Compared with size criteria, subjective reader assessment had higher sensitivity but substantially lower specificity. Areas under the ROC curve for pre- and postcontrast MR imaging were 0.76 and 0.83, respectively. Nonmetastatic nodes had significantly lower signal intensity than metastatic nodes on postcontrast T2-weighted MR images (P <.001). Postcontrast nodal staging was significantly more accurate than precontrast nodal staging (P <.01). Headache, back pain, vasodilatation, and urticaria each occurred in 6% of patients. CONCLUSION: Ferumoxtran 10-enhanced MR imaging was safe and effective and facilitated improved diagnostic performance. Use of iron oxide-enhanced MR imaging increased the positive predictive value by 20% and the accuracy by 14% compared with reader assessment. Differentiating patients with no nodal metastatic involvement was more reliable with ferumoxtran 10-enhanced MR imaging than with precontrast MR imaging.

Adolescent↗

Using CT to localize side and level of vocal cord paralysis.

OBJECTIVE: The purpose of our study was to assess the relative accuracy of imaging findings related to peripheral recurrent nerve paralysis on axial CT studies of the neck. Also assessed were imaging findings of a central vagal neuropathy. MATERIALS AND METHODS: We retrospectively identified 40 patients who had clinically diagnosed vocal cord paralysis and had undergone CT. Eight imaging signs of vocal cord paralysis were assessed, and an imaging distinction between a central or peripheral vagal neuropathy was made by evaluating asymmetric dilatation of the oropharynx with thinning of the constrictor muscles. In two patients, we studied the use of reformatted coronal images from a multidetector CT scanner. RESULTS: For unilateral vocal cord paralysis, the most sensitive imaging findings were ipsilateral pyriform sinus dilatation, medial positioning and thickening of the ipsilateral aryepiglottic fold, and ipsilateral laryngeal ventricle dilatation. In two patients, coronal reformatted images aided the diagnosis by better showing flattening of the subglottic arch. Imaging findings allowed localization of a central vagal neuropathy in four patients. CONCLUSION: Three reliable imaging findings associated with vocal cord paralysis were identified on routine axial CT studies: ipsilateral pyriform sinus dilatation, medial positioning and thickening of the ipsilateral aryepiglottic fold, and ipsilateral laryngeal ventricle dilatation. Coronal reformatted images of the larynx may be helpful, but they are not necessary in 95% of patients. Ipsilateral pharyngeal constrictor muscle atrophy is a helpful imaging finding to localize a more central vagal neuropathy. Our findings can aid radiologists in identifying peripheral and central vagal neuropathy in patients who present for CT of the neck who have a normal voice and are without a history suggestive of a vagal problem.

Female↗

CT and MR imaging findings associated with subacute thyroiditis.

Subacute granulomatous thyroiditis is an uncommon disease that occurs most often in women in their second to fifth decades of life. This disease usually presents with thyroid tenderness, a low grade fever, and occasional dysphagia. The disease resolves spontaneously, usually without thyroid function abnormalities. We herein present the CT and MR imaging findings of two cases of subacute granulomatous thyroiditis.

Adrenal Cortex Hormones↗

Orbital Lyme disease: MR imaging before and after treatment: case report.

Lyme disease is a multi-system organ disease caused by Borrelia burgdorferi. Although ocular manifestations have been reported, these remain a rare feature of the disease. To our knowledge, the radiology literature has not documented orbital Lyme disease both before and after treatment. We present the MR imaging findings of florid Lyme disease affecting the extraocular muscles in a 46-year-old man. A follow-up MR imaging study performed 6 months after a course of antibiotic therapy revealed complete resolution of the myositic changes.

Anti-Bacterial Agents↗

Granulocytic sarcoma of the temporal bone.

We report an unusual case of granulocytic sarcoma involving the temporal bone. The occurrence of this tumor usually heralds acute myelogenous leukemia or the onset of the blastic phase of chronic myelogenous leukemia. Recognition of this rare entity is important, because early aggressive chemotherapy can cause regression of the tumor, as in our case, and thus improve patient longevity.

Adult↗

Follicular adenoma in a juxtathyroidal thyroglossal duct cyst with papillary carcinoma in the adjacent thyroid gland.

This patient presented with a neck mass diagnosed as a papillary thyroid carcinoma by fine-needle aspiration. Preoperative computed tomography revealed a papillary carcinoma within a juxtathyroidal thyroglossal duct cyst. After surgery, the initial diagnosis was papillary thyroid carcinoma. After correlation with the computed tomography, the diagnosis was revised to a papillary thyroid carcinoma plus a follicular adenoma in a juxtathyroidal thyroglossal duct cyst. This case demonstrates the need for close clinical and radiographic correlation in such a complex case.

Adenoma↗