metrizamide and Epidermal-Cyst

A case of epidermoid carcinoma arising in an epidermoid cyst in the cerebellopontine angle is presented. Clinical features and CT appearance are discussed in comparison with those of benign epidermoid cyst. A 43-year-old man was admitted to the Department of Neurosurgery, University of Tokyo Hospital on April 14, 1983, with complaints of right facial numbness and weakness of six months' history. On neurological examination, sensation of the right half of the face was decreased in all modalities. Marked atrophy of the ipsilateral temporal muscle was also noted. Right facial paresis of peripheral type was evident. Gag reflex was decreased on the same side. Except for a slightly increased left deep tendon reflexes, there were no pyramidal tract signs. A CT without contrast material failed to show any abnormalities. A postcontrast CT demonstrated an irregular enhancement in the right cerebellopontine angle. The finding of asymmetry of the ambient cistern indicated minimum mass effect on the metrizamide CT cisternography. Suboccipital exploration of the right cerebellopontine angle was carried out on April 28, 1983. Leaving a part of the capsule indenting the pons between the roots of the fifth and the seventh nerve, we removed a white pearly tumor. Histological diagnosis was typical epidermoid cyst. He left the hospital one month later with signs of the right seventh and the eighth nerve. His postoperative course, however, was beyond our expectation. Over a few months following his discharge, left hemiparesis as well as horizontal and vertical nystagmus gradually developed. He was readmitted on November 10, 1983. A postcontrast CT revealed enlargement of the enhanced lesion filling the right ambient cistern.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Carcinoma, Squamous Cell; Cerebellar Neoplasms; Cerebellopontine Angle; Epidermal Cyst; Humans; Male; Metrizamide; Tomography, X-Ray Computed

Infratentorial epidermoids are rarely seen in the lifetime of a neurosurgeon. Most published series consist of a dozen or so cases. In a period of 20 years we operated on only 6 such patients. Five are doing excellently, one patient died two and a half months after operation of a fulminating infection. The follow-up is of 20 years, 9 years, and 3 years of the first three patients, while the remaining three were operated during the last year. Such an accelerated pace of epidermoid incidence in our department during the last year may be fortuitous, but may also be an indication that, many patients with vague complaints who had an epidermoid, had been missed in the past. Undoubtedly, the CT scan has greatly facilitated the diagnosis of epidermoid cysts, whether infra- or supratentorial. Diagnosis, however, hinges on suspicion or awareness on clinical grounds of the possibility of an infratentorial epidermoid. The analysis of the clinical presentation in our 6 cases, seems to allow the division of infratentorial epidermoids into those that are posteriorly located, which uniformly manifested at some stage of illness raised intracranial pressure, and the anterior epidermoids in the cerebello-pontine angle characterized by the insidious involvement of cranial nerves. Computerized tomography, in some cases with the adjunct of Metrizamide cisternography, confirms the diagnosis and delineates the spread of the lesion.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Brain Diseases; Epidermal Cyst; Female; Follow-Up Studies; Humans; Male; Metrizamide; Tomography, X-Ray Computed

Topics: Adult; Cerebellar Diseases; Cerebellopontine Angle; Epidermal Cyst; Female; Humans; Metrizamide; Myelography; Tomography, X-Ray Computed

Epidermoid cysts originating in the paramedian basal cisterns of the posterior fossa are congenital lesions that grow to a large size through slow accumulation of desquamated epithelium. These lesions grow between and ultimately displace cranial nerves, vascular structures, and the brain stem, causing a long course of progressive neurological deficits. The onset of symptoms usually occurs during the fourth decade of life. Epidermoid cysts are easily diagnosed with computerized tomography scans, which characteristically show a low-density extra-axial pattern. The primary surgical objective is to decompress the mass by evacuating the cyst contents and removing nonadherent portions of the tumor capsule; portions of the capsule adherent to vital structures should be left undisturbed. Aseptic meningitis is the most common cause of postoperative morbidity, and its incidence may be minimized by intraoperative irrigation with steroids followed by systemic therapy with dexamethasone. Symptomatic recurrences that occur many years after surgery should be managed with conservative reoperation.

Topics: Adult; Aged; Brain Diseases; Cranial Fossa, Posterior; Epidermal Cyst; Female; Humans; Male; Meningitis, Aseptic; Methods; Metrizamide; Middle Aged; Postoperative Complications; Rupture, Spontaneous; Tomography, X-Ray Computed

The characteristic findings of metrizamide CT cisternography in two cases of epidermoid are reported. The main finding was a "cauliflower-like" appearance and was thought to be caused by the irregular interstices of epidermoids. Metrizamide CT cisternography may be helpful in making a diagnosis of an epidermoid.

Topics: Adolescent; Adult; Brain Diseases; Cerebral Ventricles; Epidermal Cyst; Female; Humans; Male; Metrizamide; Sella Turcica; Tomography, X-Ray Computed

The authors describe three cases of intracranial epidermoid cysts specifically diagnosed by metrizamide CT cisternography. In CT cisternography of epidermoid cysts, metrizamide enters deep in the tumor clefts and depicts the lobulated margin of the tumor. We consider these findings are specific for this tumor and similar to the findings reported previously in pneumoencephalography or positive contrast cisternography.

Topics: Brain Diseases; Epidermal Cyst; Female; Humans; Metrizamide; Middle Aged; Pneumoencephalography; Tomography, X-Ray Computed

Topics: Adult; Brain Neoplasms; Cisterna Magna; Cranial Fossa, Posterior; Epidermal Cyst; Humans; Male; Metrizamide; Tomography, X-Ray Computed

The extent of spread of an epidermoid tumor in the posterior fossa may be difficult to discern preoperatively. Conventional computed tomographic (CT) studies may not outline the tumor capsule, and the low attenuation of the tumor itself may not allow a distinction from cerebrospinal fluid. CT metrizamide cisternography was helpful in delineating the inferior pole of an epidermoid tumor, which could then be delivered through a transtentorial approach.

Topics: Adult; Brain; Cerebellar Neoplasms; Cerebellopontine Angle; Epidermal Cyst; Female; Humans; Methods; Metrizamide; Tomography, X-Ray Computed

The diagnosis of intracranial cystic lesions is greatly facilitated by cranial computerized tomography (CT) which eliminates the need for further invasive neuroradiological studies. However, cystic lesions with thin walls that do not enhance following intravenous contrast infusion, especially when they are located in the midline and at the base of the skull, may become a diagnostic problem preventing proper management and therapy. We discuss 12 midline intracranial lesions, including one that is noncystic, to emphasize the limitations of CT in showing these lesions and the need for further diagnostic studies such as pneumoencephalography and metrizamide CT. The limitations of CT in diagnosing these lesions are related to the variations in the anatomy at the base of the skull (supra-sellar region); the varying pathological nature and behavior of certain cystic lesions such as epidermoid tumors and craniopharyngiomas; and the compromising of the spatial and density resolutions due to the partial volume effect. The complementary role of studies such as pneumoencephalography and CT metrizamide cisternography for the evaluation of the dynamics of the cerebrospinal fluid that are necessary for the proper management and therapy of patients is discussed.

Topics: Adult; Astrocytoma; Brain Diseases; Brain Neoplasms; Child, Preschool; Craniopharyngioma; Cysts; Diatrizoate Meglumine; Epidermal Cyst; Female; Humans; Male; Metrizamide; Pneumoencephalography; Radiographic Image Enhancement; Subarachnoid Space; Tomography, X-Ray Computed