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Biomedical subjects

M Castillo

Publications and source records attributed to M Castillo.

358 records · Page 20Linked to original sources
PubMedDate not supplied

Computed tomography of gliosarcoma.

Five cases of rare gliosarcoma are described with pathologic correlation. Because of its sarcomatous component, gliosarcoma tends to present as a sharply defined, round or lobulated, hyperdense solid mass with relatively homogeneous contrast enhancement and peritumoral edema. Sharp demarcation of the tumor from surrounding tissue may lead to complete removal and prolonged survival despite high malignancy. However, aggressive tumor regrowth occurs often after incomplete resection. The genesis of gliosarcoma is also discussed.

Adolescent↗
PubMedDate not supplied

[Mesenteric lipodystrophy].

This case report describes the clinic and pathologic findings of an inflammatory pseudotumor of the mesentery in a 43 years old male. Previous to the hospital admission he had several episodes of intestinal occlusion and an abdominal mass. Computed tomography and mesenteric angiography were very helpful. Laboratory tests were unspecific, and the final diagnosis was obtained after surgery and histologic study of the lesion. We review published literature on inflammatory pseudotumors.

Adult↗
PubMedDate not supplied

MR in squamous cell carcinoma of the lacrimal sac.

A case of squamous cell carcinoma arising from the right lacrimal sac is presented. MR T2-weighted images showed a mass of low signal intensity in the right medial canthus extending into the nasolacrimal duct. This led us to postulate a high-grade malignant neoplasm arising in the lacrimal sac.

Biopsy↗
PubMedDate not supplied

Basal ganglia hemorrhage related to lightning strike.

We describe a case of bilateral basal ganglia hemorrhage after a lightning strike to the head documented by a CT scan. Review of the literature shows this to be the most common brain imaging finding that can be attributed to a lightning strike. Several mechanistic theories are discussed, with the most plausible one being related to preferential conduction pathways through the brain.

Adult↗
PubMedDate not supplied

Bilateral nasolacrimal duct mucocele, a rare cause of respiratory distress: CT findings in two newborns.

Two newborns presented with severe respiratory distress caused by nasal obstruction. CT showed bilateral soft-tissue masses located under the inferior turbinates at the level of the inferior meatuses. Histologic examination showed the lesions to be compatible with nasolacrimal mucoceles. The embryology and radiographic features of this rare anomaly are discussed.

Humans↗
PubMedDate not supplied

Proton MR spectroscopic characteristics of a presumed giant subcortical heterotopia.

A newborn presented with a mass replacing the left cerebral hemisphere. Although the internal signal characteristics of the lesion were suggestive of disorganized gray and white matter, a true neoplasia such as a ganglioglioma could not be totally excluded. Biopsy is not recommended in these cases since the results may be misleading. Proton MR spectroscopy was used; this technique also suggested the hamartomatous nature of the lesion. Based on the clinical course and the imaging features, conservative therapy and observation were undertaken instead of surgery. At 6 months of age, the patient is stable and the lesion is unchanged.

Brain Neoplasms↗
PubMedDate not supplied

Rhabdomyosarcoma of the middle ear: imaging features in two children.

The imaging features are presented in two cases of rhabdomyosarcoma arising from the middle ear during childhood, an extremely rare and aggressive neoplasia. CT provides excellent information concerning the degree of bone involvement; contrast-enhanced MR imaging clearly delineates subcranial and/or intracranial extension.

Child, Preschool↗
PubMedDate not supplied

CT findings in a case of pharyngeal rhinoscleroma.

The author describes the infectious disease rhinoscleroma and calls for its consideration in the differential diagnosis of nasal, pharyngeal, and tracheal masses seen in young immigrants.

Adult↗
PubMedDate not supplied

MR of recurrent high-grade astrocytomas after intralesional immunotherapy.

PURPOSE: To describe the MR findings in six patients with recurrent cerebral astrocytomas before, immediately after, and 3 months after local immunotherapy with tumor-infiltrating lymphocytes and interleukin-2. METHODS: Contrast-enhanced MR studies were obtained in six patients (three with anaplastic astrocytoma and three with glioblastoma multiforme) at the time of tumor recurrence, after a second resection and placement of an Ommaya catheter, at the end of immunotherapy, and thereafter at 3-month intervals. These MR studies were reviewed with special attention to pattern and degree of enhancement, edema, and mass effect. RESULTS: In three patients, gross total removal of recurrent tumor was achieved and postimmunotherapy MR studies showed a flare phenomenon characterized by increased nodular enhancement, increased edema, and mass effect. On the 3-month follow-up examination, these findings had resolved, and no further tumor recurrence was seen during the following 12-month period. Neither of the two patients who had subtotal resection had a flare phenomenon. In one of these patients, the tumor was stable at the 12-month follow-up; the other patient had recurrent tumor at the 6-month follow-up. In the last patient, who also had subtotal tumor resection and progressive enhancement after immunotherapy, tumor progression was rapid. CONCLUSION: After local immunotherapy, increased enhancement, edema, and mass effect are most likely the result of a flare phenomenon, but because rapid tumor progression may produce similar features, follow-up MR studies are indispensable. The flare phenomenon resolved by 3 months in all patients.

Adult↗
PubMedDate not supplied

Imaging of facial anomalies.

Anomalies of the face may occur in its lower or middle segments. Anomalies of the lower face generally involve the derivatives of the branchial apparatus and therefore manifest as defects in the mandible, pinnae, external auditory canals, and portions of the middle ears. These anomalies are occasionally isolated, but most of them occur in combination with systemic syndromes. These anomalies generally do not occur with respiratory compromise. Anomalies of the midface may extend from the upper lip to the forehead, reflecting the complex embryology of this region. Most of these deformities are isolated, but some patients with facial clefts, notably the midline cleft syndrome and holoprosencephaly, have anomalies in other sites. This is important because these patients will require detailed imaging of the face and brain. Anomalies of the midface tend to involve the nose and its air-conducting passages. We prefer to divide these anomalies into those with and without respiratory obstruction. The most common anomalies that result in airway compromise include posterior choanal stenoses and atresias, bilateral cysts (mucoceles) of the distal lacrimal ducts, and stenosis of the pyriform (anterior) nasal aperture. These may be optimally evaluated with computed tomography (CT) and generally require immediate treatment to ensure adequate ventilation. Rare nasal anomalies that also result in airway obstruction are agenesis of the pharynx, agenesis of the nose, and hypoplasia of the nasal alae. Agenesis of the nasopharynx and nose are complex anomalies that require both CT and magnetic resonance imaging (MRI). The diagnosis of hypoplasia of the nasal alae is a clinical one; these anomalies do not require imaging studies. Besides facial clefts, anomalies of the nose without respiratory obstruction tend to be centered around the nasofrontal region. This is the site of the most common sincipital encephaloceles. Patients with frontonasal and nasoethmoidal encephaloceles require both CT and MRI. In these patients, imaging of the brain is essential. Patients with suspected extranasal, intranasal, or mixed heterotopia may need images with CT or MRI or both. The last of the anomalies in this region is the presence of ectodermlined tracts and sinuses that may or may not be accompanied with masses. When these masses are located in the midline, they are almost always dermoids, whereas masses located off-midline may also be epidermoids. This latter group of anomalies is important because of its potential communication with the intracranial contents and the possibility of infection. Adequate imaging may require both CT and MRI. Midline facial clefts may be divided into common and complex. Common clefts represent the great majority and are isolated cosmetic defects that generally do not require imaging studies. Complex facial clefts with hypertelorism are almost always a part of the holoprosencephalies; imaging of the brain is more important than is imaging of the cleft proper. The studies should be obtained with MRI. Complex facial clefts in the presence of hypertelorism are most likely related to the midline cleft syndromes. This very rare and intricate group of disorders is generally accompanied with severe brain and eye anomalies. Imaging of these patients is better performed with both CT and MRI. We review common and uncommon facial anomalies. We have tried to approach them according to their clinical importance by dividing them into those with and without airway compromise.

Face↗
PubMedDate not supplied

Proton MR spectroscopy of squamous cell carcinoma of the extracranial head and neck: in vitro and in vivo studies.

PURPOSE: To determine the ability of in vitro one-dimensional and two-dimensional proton MR spectroscopy to help differentiate squamous cell carcinoma of the extracranial head and neck from normal tissues and to correlate the in vitro observations with clinical studies. METHODS: In vitro 1-D and 2-D correlated proton MR spectroscopy (11 T) was performed in tissue specimens of squamous cell carcinoma of the head and neck (n = 19), in normal tissue (n = 13), in metastatic cervical lymph nodes (n = 3), and in a squamous cell carcinoma cell line. In vivo 1-D proton MR spectroscopy (1.5 T) was performed in patients with squamous cell carcinoma (n = 7) and in healthy volunteers (n = 7). The ratio of the areas under the choline (Cho) and creatine (Cr) resonances were calculated for 1-D proton MR spectra for the in vitro tissue studies and correlated with the in vivo studies. Data from in vitro 2-D correlated spectroscopy were analyzed for differences in the presence or absence of various metabolites in samples of tumor and normal tissue. Statistical analysis consisted of 2 x 2 factorial repeated measures analysis of variance (ANOVA), discriminate analysis, and chi2 test. RESULTS: The mean in vitro 1-D proton MR spectroscopic Cho/Cr ratio was significantly higher in tumor than in normal tissue. The difference between the mean ratios appeared to increase with increasing echo time. All in vivo tumor Cho/Cr ratios were greater than the calculated mean in vitro tumor ratio, whereas six of the seven volunteers had no detectable Cho and Cr resonances. Two-dimensional correlated MR spectroscopic data revealed that a variety of amino acids have a significantly greater likelihood of being detected in tumor than in normal tissues. CONCLUSIONS: One-dimensional and 2-D proton MR spectroscopy can help differentiate primary squamous cell carcinoma and nodal metastases containing squamous cell carcinoma from normal tissue both in vitro and in vivo. In addition, 2-D spectroscopy can help identify the presence of certain amino acids in squamous cell carcinoma that are not detected in normal tissue.

Carcinoma, Squamous Cell↗