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D Armao

Publications and source records attributed to D Armao.

15 recordsLinked to original sources
PubMed2001

Cervical nodal metastases in squamous cell carcinoma of the head and neck: what to expect.

The treatment and management of malignancies of the head and neck is directly altered by the presence of metastatic cervical adenopathy. The treatment of nodal metastases in squamous cell carcinoma of the head and neck (HNSCCA) is determined by the lymphatic drainage of the upper aerodigestive tract. The lymphatic drainage is site-specific and occurs in a predictable manner. The purpose of this text is to provide an overview of the normal routes of lymphatic drainage in the head and neck and correlate this with the current nodal classification system. The specific aims of this manuscript are to 1) illustrate the expected lymphatic drainage patterns of HNSCCA arising in the different subsites (nasopharynx, oropharynx, oral cavity, larynx, and hypopharynx) and 2) review the expected frequency of metastases within nodal groups for HNSCCA that arise in these locations. An understanding of the topographical distribution and incidence of cervical lymph node metastases plays an integral role in the physical examination and radiological evaluation of patients with HNSCCA. For the neuroradiologist, this information may increases the ability to identify those nodal groups at risk for metastatic involvement.

Carcinoma, Squamous Cell↗
PubMed2001

CT detection of mandibular invasion by squamous cell carcinoma of the oral cavity.

OBJECTIVE: The purpose of this study was to determine the diagnostic accuracy of CT in detecting mandibular invasion by squamous cell carcinoma of the oral cavity. MATERIALS AND METHODS: Forty-nine patients who had squamous cell carcinoma of the oral cavity that was clinically fixed to the mandible were treated with mandibulectomy. All patients underwent contrast-enhanced CT (contiguous 3-mm-thick sections) through the primary site before surgery. All studies were reconstructed with bone algorithm. These studies were retrospectively reviewed by a neuroradiologist for evidence of mandibular invasion. The imaging results were compared with the histologic findings in all cases. RESULTS: CT correctly revealed 25 of 26 cases with mandibular invasion. CT correctly excluded mandibular invasion in 20 of 23 cases without invasion. The diagnostic accuracy of CT for detecting mandibular invasion was as follows: sensitivity, 96%; specificity, 87%; positive predictive value, 89%; and negative predictive value, 95%. CONCLUSION: Thin-section (3-mm) CT reconstructed with bone algorithm is an accurate technique to detect mandibular involvement by squamous cell carcinoma of the oral cavity.

Adult↗
PubMed2001

Demyelinating diseases, leukodystrophies, and other myelin disorders.

Magnetic resonance (MR) imaging recently has become the most sensitive clinical test in the detection of white matter disorders, yet neuropathologic evaluation remains the most specific. This article describes the gross and microscopic pathology of various diseases primarily or selectively affecting white matter. The discussion should provide deeper insight into the nature of white matter disease and assist in the interpretation of CT and MR images. The subject of white matter damage caused secondarily by such entities as neoplasia, trauma, infarction, or neuronal degeneration is not included.

Adolescent↗
PubMed2000

Nasal chondroma.

Explore the source record for details and available documents.

Chondroma↗
PubMed2000

Colloid cyst of the third ventricle: imaging-pathologic correlation.

Colloid cysts are relatively rare intracranial lesions located in the rostral aspect of the third ventricle. They may produce acute hydrocephalus, brain herniation, and lead to death. Although the clinical and imaging features of colloid cysts are well known, their etiology and the factors responsible for their imaging features continue to be a subject of debate. We present the imaging-pathologic correlation of a patient with a colloid cyst as well as data supporting the fact that the presence of cholesterol is probably responsible for the MR imaging features exhibited by some colloid cysts.

Adult↗
PubMed1999

Histiocytic lesion mimicking intrinsic brainstem neoplasm. Case report.

This 10-year-old girl presented with a 1-month history of progressive bulbar palsy and a solitary enhancing mass originating within the floor of the fourth ventricle. Results of initial imaging studies and presentation were suggestive of neoplasia. Subtotal resection was performed and pathological examination revealed the mass to be a histiocytic lesion, with no evidence of a glioma. The patient had no other stigmata of histiocytosis and was treated with steroid medications, resulting in prolonged resolution of the lesion. This case demonstrates that for discrete brainstem lesions the differential diagnosis includes entities other than glioma for which treatment is available. Biopsy sampling should be considered when technically feasible.

Brain Diseases↗
PubMed1997

Neutral proteases and disruption of the blood-brain barrier in rat.

Blood-brain barrier disruption is common in many neurological diseases. Matrix metalloproteinases are induced in brain injury and increase capillary permeability by attacking the extracellular matrix around cerebral capillaries. Other neutral proteases are also increased in sites of secondary injury, and may contribute to the proteolysis of the blood-brain barrier. Therefore, we studied capillary permeability and histological tissue damage after intracerebral injection of neutrophil elastase, cathepsin G, heparatinase and plasmin. Adult rats were injected intracerebrally with an enzyme. After 1, 4 or 24 h, measurements were made of brain uptake of a radiolabeled tracer, [14C]sucrose. Enzymes that significantly increased capillary permeability were injected into other rats for histological assessment of tissue damage. Elastase increased capillary permeability significantly when compared with controls; maximal damage was seen at 4 h. Plasmin produced smaller increases in permeability at 4 h, exerting its maximal effect on sucrose uptake at 24 h. Cathepsin G had a small effect at 4 h. Heparitinase had no effect. Histologic examination of elastase-injected brains at 24 h revealed multifocal perivascular and intraparenchymal acute hemorrhages accompanied by a polymorphonuclear cell infiltrate. Elastase-injected brains were microscopically similar to saline-injected brains at 1 and 4 h. Plasmin produced fibrinoid changes in the blood vessels at 24 h, coinciding with the maximal increase in capillary permeability. We conclude that neutrophil elastase attacks the capillary extracellular matrix, causing extensive hemorrhage, while plasmin leads to increased vascular permeability and fibrinoid necrosis of blood vessel walls. Differential effects of neutral proteases released secondary to injury could be important in both the acute changes in blood vessel permeability and long-term alterations in vessel structure.

Animals↗
PubMed1981

Varix of the vortex ampulla.

In five patients, extreme gaze resulted in the appearance and expansion of a lesion located at the site of a venous vortex ampulla. The dimensions and color of the lesion varied depending upon the direction and duration of gaze. The lesion expanded when the head was positioned below the level of the heart and when a Valsalva maneuver was performed, even when the primary position of gaze was maintained. The lesion rapidly detumesced and disappeared when the head was elevated, digital pressure was exerted on the globe, or gaze was directed elsewhere. Fluorescein angiography confirmed that this tumefaction originated from the venous vortex ampulla. These dynamic features observed ophthalmoscopically and demonstrated by ultrasonography are characteristic of the vortex ampulla varix; the lesion should not be confused with a malignancy.

Aged↗
PubMedDate not supplied

Papillary carcinoma in a giant thyroglossal duct cyst.

Thyroglossal duct cysts (TGDCs) are common, however, a malignancy occurring in a TGDC is rare. The presence on an underlying malignancy is clinically occult but may be detected on preoperative imaging studies. We describe the CT findings of a papillary carcinoma occurring in a TGDC.

Adult↗
PubMedDate not supplied

Midline spinal cord hamartomas: MR imaging features of two patients.

Congenital midline spinal hamartomas are relatively rare. Patients harboring this anomaly are generally asymptomatic, but present with an overlying skin anomaly. MR imaging depicts a mass that is isointense with the spinal cord on all sequences, and may show a dermal sinus tract that tethers the cord at the level of the lesion. We report the MR features of congenital midline spinal hamartoma in two children.

Child↗