Ultrasound-guided fine-needle aspiration of the thyroid assessed by Ultrafast Papanicolaou stain: data from 1135 biopsies with a two- to six-year follow-up.

One of the limitations of fine-needle aspiration (FNA) of the thyroid is difficulty in distinguishing the follicular variant (FV) of papillary thyroid carcinomas (PTC) from follicular neoplasms. By highlighting the "Orphan Annie-eyed" clear nuclei of the former, the Ultrafast Papanicolaou stain (UFP) easily separates these two entities. One thousand one hundred thirty-five ultrasound-guided FNAs of the thyroid were assessed by UFP with immediate biopsy results reported to the patients in a busy radiology office in Manhattan from November 1994 to December 1998. Of the 77 thyroid cancers resected, 22 were FVPTC and 17 were microcarcinomas (1 medullary carcinoma, 16 PTC). The rates of "unsatisfactory," "cancer," "suspicious for cancer," "follicular neoplasm," and "benign" cytology were 0.7%, 4.4%, 2.6%, 10.2%, and 82.1%, respectively and the cancer yields at surgery were 98%, 81.8%, 15.8%, and 0% respectively. Of the 1127 satisfactory FNAs in the series with a 2- to -6 years of clinical follow-up, a false-negative rate of 0% and a false-positive rate of 1.5% were obtained. Of the 169 surgical follow-ups with satisfactory FNAs, a sensitivity of 100%, specificity of 66.7%, positive predictive value of 87.4%, negative predictive value of 100%, and global accuracy of 89.9% were achieved. The paradoxical combination of low unsatisfactory rate and low false-negative rate is attributed to (1) the use of needle puncture without syringe to obtain enough microfollicles from the exceedingly bloody aspirates from follicular neoplasms for a diagnosis, (2) eliciting history of neck trauma to confirm hematomas, (3) using UFP to highlight the grape-like watery clear nuclei of FVPTC evident with a 4x objective, and (4) the precise guidance by ultrasound in sampling microcarcinomas.

Computed tomographic scanning for locating an emplaced plastic orbital plate.

An emplaced plastic plate was demonstrated by computed tomographic scanning five years after surgical implantation because of fracture of the orbital floor, proving that it had remained in proper position and that the patient's complaints were unrelated to its presence in the orbit. To the best of our knowledge, this is the first instance in which this method had been used intentionally to achieve noninvasive localization of an orbital plastic plate. It is a valuable and accurate adjunct in ascertaining possible migration or early extension of the emplaced implant.

Cranial computerized tomography. A radiologic-pathologic correlation.

One hundred twenty-three patients having cranial computerized tomography (CT) within two months of death were reviewed to determine the accuracy of CT. Those patients having scans within two weeks of death on the 160-matrix EMI head scanner had a false-negative rate of 11%. Approximately one third of all lesions 1 cm or more were not demonstrated. Computerized tomography appears to be the most sensitive neuroradiologic diagnostic tool, but certainly is not infallible.

Preoperative diagnosis of brain-stem abscess by computerized tomography with survival. Case report.

A case is reported in which the diagnosis of brain-stem abscess was made preoperatively by computerized tomography. Surgical therapy resulted in relatively good functional recovery.

Computerized tomography of the head: a preliminary report on its use in the diagnosis of internal auditory canal and cerebellopontine lesions.

Computerized tomography (CT) of the head in rapidly replacing other procedures in the diagnosis of lesions of the cerebellopontine angle and the internal auditory canal. The quality of the information is such that CT may become the only procedure necessary for the diagnostic examination. It substantially diminishes time, expense, and possible radiation hazard to the patient.

Computed tomography: demonstration of contrast medium within cystic tumors.

Two cases demonstrated that intravenously injected contrast medium entered cystic lesions. It appears that both vascular opacification and transgression of the blood-brain barrier play major roles in contrast enhancement.

Computed tomography; the anatomic basis of the zone of diminished density surrounding meningiomas.

Computed tomography of meningiomas often demonstrates a zone of diminished density surrounding the actual tumor. This zone may be related to widening of the subarachnoid space, cerebral edema, tissue necrosis, or demyelination. A case is presented in which the anatomic basis of the zone of diminished density was shown on pneumoencephalography and at surgery to be an enlarged subarachnoid space.

Computed tomography: evaluation of the posterior third ventricle.

The normal computed tomography (CT) appearances of the posterior third ventricle and related structures are presented. Seventy-six patients with lesions directly involving this ventricle were studied by CT, and results of other neuroradiological procedures evaluated. Primary tumors, metastases, hematomas, infarcts, and cysts may be reliably distinguished by CT, particularly if contrast enhancement is utilized. Size and density resolution limit the direct visualization of the aqueduct of Sylvius; stenosis however may be inferred. Small infarcts may be difficult to demonstrate by the use of CT scans without contrast enhancement, yet be shown by isotope scans.

Computed tomography: contrast media within subdural hematomas. A preliminary report.

Delayed computed tomographic scans may be most helpful in disclosing subdural hematomas which have collected contrast media when the lesion is undisclosed by initial or immediate post-contrast scans.

Computed tomography in metastatic disease of the brain.

Computed tomography has been found to be a more accurate diagnostic tool in the analysis of brain metastases than radionuclide scanning. Of 1,100 patients studied by CT scan, 57 showed evidence of intracerebral metastasis, and 14 showed evidence of hydrocephalus. Density levels below that of normal brain tissue were found in cases of metastases from the lung (13), breast (7), melanoma (4), kidney (3), lymphoma (3), and nasopharynx (1); levels above normal were found in cases of metastases from melanoma (8), lung (3), colon (3), chorionic carcinoma (2), osteogenic sarcoma (1), and kidney (1).

Computer tomography: the "resolving" intracerebral hemorrhage.

Two patients with a total of 4 intracerebral hemorrhages were examined by serial computer tomography (CT) over a period of up to 6 months, revealing a progressive decrease in lesion volume and density which eventually became less than that of the surrounding brain tissue. These changes were interpreted as complete clot resorption with cystic residue. However, postmortem examination revealed residual hematomas with no evidence of recent bleeding. Three of these correspond in size to those noted on the initial CT scans. Intraparenchymal hemorrhages have stages of organization and resolution which may simulate normal brain density without significant volumetric alteration.

Neuroepithelial (colloid) cysts. Pathogenesis and unusual features.

A brief history of the theories of pathogenesis of the origin of neuroepithelial cysts is presented. An origin more diffuse than the paraphysis seems most likely in our opinion, and we attempt to substantiate this theory with several of the cases from our series. One posterior third ventricular neuroepithelial cyst and one in the fourth ventricle are demonstrated roentgenographically. Also included in our series are a case showing suprasellar calcification on plain skull roentgenograms, not previously reported in neuroepithelial cysts, and a case with a cyst measuring 9 cm, the largest neuroepithelial cyst yet reported.