Intradiploic arachnoid cyst identified by diffusion-weighted magnetic resonance imaging--case report

A 72-year-old woman presented with an intradiploic arachnoid cyst in the occipital intradiploic space which was found incidentally by magnetic resonance (MR) imaging. Computed tomography revealed a widened diploic space and thinning of the inner and outer tables of the occipital bone. The cyst appeared as isointense to the cerebrospinal fluid on both T1- and T2-weighted images. The differential diagnosis of intradiploic epidermoid cyst could be excluded because the lesion was low intensity on diffusion-weighted MR images. Arachnoid cyst is a benign lesion, so exploratory surgery should be avoided unless the cyst is symptomatic. Diffusion-weighted MR imaging is an effective modality to distinguish diploic epidermoid cysts from arachnoid cysts.     

Posterior fossa epidermoid cysts presenting with unusual radiological appearances--two case reports

Intracranial epidermoid cysts generally appear as hypodense on computed tomography (CT), hypointense on T(1)-weighted magnetic resonance (MR) imaging, and hyperintense on diffusion-weighted MR imaging. We report two cases of posterior fossa epidermoid cysts with unusual radiological features. A 49-year-old male presented with facial dysesthesia and a 12-year-old male presented with diplopia and internuclear ophthalmoplegia. CT of both cases revealed hyperdense lesions. MR imaging showed the first case as hypointense in the posterior part and hyperintense in the anterior part of the tumor on diffusion-weighted imaging, and the second case as hyperintense on diffusion-weighted and T(1)-weighted MR imaging. Surgical exploration revealed that the tumors consisted of creamy materials, instead of the usual semi-solid or flaky texture in epidermoid cysts. Xanthochromic serous fluid was also contained in the superoposterior half of the cyst of the first case. These unusual contents of the cyst may be responsible for the unusual neuroimaging findings. Histological examination showed both cysts were lined with stratified squamous epithelium and contained keratinaceous materials. Therefore, epidermoid cysts can occasionally present with unusual radiological characteristics giving rise to a diagnostic pitfall.     

Intramedullary epidermoid cysts of the spinal cord. Case report.

Epidermoid cysts are tumors familiar to neurosurgeons, but intramedullary epidermoid cysts are rare. The authors report the case of a 6-year-old girl presenting with progressive paraparesis. A midthoracic intramedullary mass was revealed on myelography and magnetic resonance (MR) imaging and confirmed as an intramedullary epidermoid cyst at surgery, at which time the cyst was removed. This is the fourth report documenting a purely intramedullary epidermoid cyst occurring in a child. The pathology and etiology, epidemiology, clinical features, radiology (including MR image characteristics), and surgical treatment of such rare intramedullary benign tumors are discussed. Magnetic resonance imaging reduces the delay in diagnosis of spinal cord tumors but should be guided by clinical judgment.     

Acquired lumbar epidermoid cyst in an adult

A 61-year-old female complained of low back pain, and had been treated by spinal anesthetic injection more than 70 times over 14 years. Magnetic resonance (MR) imaging, performed at the age of 47 years, revealed no abnormal lesion. However, she developed irritable hypesthetic pain in the left leg at 61 years of age. MR imaging revealed a round mass appearing isointense on the T1-weighted and slightly hyperintense on the T2-weighted images. Laminectomy revealed an epidermoid cyst, which was removed. This case clearly demonstrates that adults can acquire epidermoid tumor which very probably has an iatrogenic origin. The incidence of epidermoid tumor is low, but we should be aware of the potential adverse complications such as formation of epidermoid tumors after lumbar puncture.     

A case of pineal epidermoid cyst showing an interesting magnetic resonance imaging

A case of pineal epidermoid cyst with interesting findings of magnetic resonance imaging (MRI) is reported referring to the literature. In our case, homogeneous high density area is seen on CT and high signal intensity is recognized on T1-weighted MRI and low signal intensity on T2-weighted MRI.     

Testicular epidermoid cyst in Klinefelter''s syndrome

A 38-year-old Japanese man was referred to our outpatient clinic for treatment of infertility. Semen analysis showed azoospermia. Chromosome analysis revealed a 47XXY karyotype, and non-mosaic Klinefelter's syndrome (KFS) was diagnosed. Upon physical examination, the patient's right testicular volume was 30 mL and the left testicular volume was 3 mL. Laboratory tests showed normal levels of lactate dehydrogenase, alpha-fetoprotein, and human chorionic gonadotropin beta-subunit. The plasma luteinizing hormone and follicle-stimulating hormone levels were increased to 15.7 mIU/mL and 45.9 mIU/mL, respectively. The plasma testosterone was decreased to 0.25 ng/mL. Magnetic resonance imaging showed a right testicular mass of low-signal intensity on the T1-weighted image and of high-signal intensity on the T2-weighted image. Therefore, the final diagnosis was KFS with a right testicular tumor. Thus, a right high orchiectomy was performed. Histological examination revealed an epidermoid cyst of the right testis. Epidermoid cysts in cases of KFS are rare. To our knowledge, only seven cases, including ours, have been reported in the literature.     

Pineal region metastasis appearing as hypointensity on T2-weighted magnetic resonance imaging--case report

A 48-year-old female presented with headache and limitation of upward gaze. She had a history of total gastrectomy for gastric adenocarcinoma 2 years previously. Computed tomography with contrast medium and T1-weighted magnetic resonance (MR) imaging with gadolinium showed ring-like enhancement of a solitary mass in the pineal region with obstructive hydrocephalus. T2-weighted MR imaging showed the tumor as hypointense. This MR imaging finding complicated the preoperative diagnosis, but malignancy was suspected from the medical history. The tumor was subtotally resected via the occipital transtentorial approach with a rigid endoscope. Histological examination of the surgical specimen revealed adenocarcinoma cells with extensive coagulation necrosis, which might have contributed to the hypointensity on T2-weighted MR imaging. Correct diagnosis of metastatic adenocarcinoma based only on MR imaging may be difficult in such cases, but metastatic adenocarcinoma of the pineal region must be considered in the differential diagnosis of pineal tumors.     

Diploic epidermoid cyst: case report

We report the case of a diploic epidermoid cyst in the left front-parietal bone of a 70-year-old woman. A skull x-ray showed an osteolytic lesion with a sclerotic border, and CT scan revealed a low/iso-density mass and the destruction of both inner and outer tables. MRI showed hypo-intensity on T1-weighted image, hyper-intensity on T2-weighted imaging and remarkably-strong intensity on the diffusion-weighted imaging. Gadolinium enhancement was seen in the tumor capsule and dura of the peripheral tumor. In the operative view, most of the bone edge was regular with a sclerotic border, but an irregular section was present. The tumor adhered strongly to the dura mater and periosteum. The tumor was totally extirpated with the peripheral skull, dura mater and periost. On the postoperative MRI, gadolinium enhancement of the nearby dura mater and disappeared. We have added a discussion of the radiological features of diploic epidermoid cysts.     

Intracranial epidermoid tumor with changes in signal intensity on magnetic resonance imaging because of non-hemorrhagic pathology: case report

A 61-year-old woman presented an intracranial epidermoid tumor manifesting as dizziness and right facial hypesthesia. Magnetic resonance (MR) imaging revealed a well-defined lobulated mass in the right cerebellopontine angle as nearly isointense to the cerebrospinal fluid (CSF) on both T(1)- and T(2)-weighted images but inhomogeneously hyperintense on fluid-attenuated inversion recovery images. MR imaging performed 1 year later revealed that the tumor had significantly enlarged, and now appeared hyperintense to the CSF on T(1)- and T(2)-weighted images. The lesion was confirmed at surgery to be an epidermoid tumor filled with xanthochromic fluid. Histological examination found no evidence of hemorrhage in the resected tumor, so the changes in the MR imaging signal intensity were attributed to changes in the protein concentration of the intratumoral fluid, accumulation of debris, or some other non-hemorrhagic process.     

Magnetic resonance appearance of multiple intracranial epidermoid cysts: intrathecal seeding of the cysts? Case report

A 44-year-old man presented to the hospital with multiple intracranial epidermoid cysts. The clinical manifestations of his disease included chronic headaches and one seizurelike episode. Findings determined by magnetic resonance (MR) imaging, surgery, and histological analysis indicated intrathecal and intraventricular seeding of the cysts. Spontaneous (nontraumatic) seeding of multiple daughter cysts from intracranial epidermoid cysts is still very rare and their multiple appearances on MR imaging should be distinguished from the simple scattering of oily contents due to cyst rupture.     

脊髓内胆脂瘤的诊断和手术治疗

目的提高脊髓内胆脂瘤的诊断水平及选择治疗方法。方法总结１９７８～１９９５年收治的经手术和病理证实的１０例脊髓内胆脂瘤的经验。结果患者临床表现无特异性。本组ＣＴ检查８例，显示肿瘤呈现均匀低密度影像，边界清楚，强化扫描多无增强。ＭＲ检查４例，肿瘤呈现信号强度变化不定的特点，边界清楚。１０例患者均行手术治疗，肿瘤全切除１例，次全切除９例。８例术后得以随访，无复发。结论肿瘤全切是治疗本病的最好选择。     

Endoscopic Surgery for Hemorrhagic Pineal Cyst Following Antiplatelet Therapy: Case Report

Pineal cysts of the third ventricle presenting with acute obstructive hydrocephalus due to internal cystic hemorrhage are a rare clinical entity. The authors report a case of a 61-year-old man taking antiplatelet medication who suffered from a hemorrhagic pineal cyst and was treated with endoscopic surgery. One month prior to treatment, the patient was diagnosed with a brainstem infarction and received clopidogrel in addition to aspirin. A small incidental pineal cyst was concurrently diagnosed using magnetic resonance (MR) imaging which was intended to be followed conservatively. The patient presented with a sudden onset of headache and diplopia. On admission, the neurological examination revealed clouding of consciousness and Parinaud syndrome. Computerized tomography (CT) scans demonstrated a hemorrhagic mass lesion in the posterior third ventricle. The patient underwent emergency external ventricular drainage with staged endoscopic biopsy and third ventriculostomy using a flexible videoscope. Histological examination revealed pineal tissue with necrotic change and no evidence of tumor cells. One year later MR imaging demonstrated no evidence of cystic lesion and a flow void between third ventricle and prepontine cistern. In patients with asymptomatic pineal cysts who are treated with antiplatelet therapy, it is important to be aware of the risk of pineal apoplexy. Endoscopic management can be effective for treatment of hemorrhagic pineal cyst with obstructive hydrocephalus.     

Symptomatic pineal cyst: case report and review of the literature

Asymptomatic cysts of the pineal region are common incidental findings in adults. In contrast, symptomatic pineal cysts are rare and their management is not well defined. We present the case of a 39-year-old woman suffering from intracranial hypertension, with visual disturbance and mild papilledema. The MR images showed a voluminous cyst of the pineal region responsible for an obstructive hydrocephalus. Endoscopic treatment with the aid of computerized neuronavigation consisting in third ventriculostomy and fenestration of the cyst was performed. Intracranial hypertension symptoms resolved in 24 hours. The one year follow-up cerebral MR images demonstrated the normalization of ventricular size with patency of the aqueduct of Sylvius. Reviewing the literature demonstrates that the endoscopic approach represents a minimally invasive and safe procedure in the treatment of symptomatic pineal cysts.     

Dorsal intramedullary spinal epidermoid cysts: Report of two cases and review of literature

Intramedullary epidermoid cysts of the spinal cord are rare tumors, especially those not associated with spinal dysraphism. About 50 cases have been reported in the literature. Of these, only seven cases have had magnetic resonance imaging (MRI) studies. We report two cases of spinal intramedullary epidermoid cysts with MR imaging. Both were not associated with spina bifida. In one patient, the tumor was located at D4 vertebral level; while in the other, within the conus medullaris. The clinical features, MRI characteristics and surgical treatment of intramedullary epidermoid cyst are presented with relevant review of the literature.     

Rathke cleft cyst intracystic nodule: a characteristic magnetic resonance imaging finding

OBJECT: The fluid content of Rathke cleft cysts (RCCs) displays variable appearances on magnetic resonance (MR) images and can appear indistinguishable from other intrasellar or suprasellar cystic lesions. Intracystic nodules associated with individual RCCs have been noted, but to date their significance has not been fully explored. METHODS: The authors retrospectively reviewed MR imaging studies obtained in patients harboring intrasellar or suprasellar lesions that were consistent with RCCs to identify the presence and imaging characteristics of intracystic nodules. An intracystic nodule was present in nine (45%) of 20 patients with an RCC. All intracystic nodules were clearly visible and displayed a characteristic low signal intensity on T2-weighted MR images. The nodule was only visualized on T1-weighted images in four cases, in which it exhibited a consistent high signal intensity similar to that of the cyst fluid. The nodules did not enhance following the intravenous administration of a contrast agent. CONCLUSIONS: Although it is difficult to differentiate RCCs from other sellar cystic lesions because of the variable signal intensities displayed on MR images, the intensity of the intracystic nodule seems consistent on T1- and T2-weighted images, and the nodule is always clearly visible on T2-weighted images. With a nonenhancing cystic lesion that does not cause significant symptoms in the patient, the identification of an intracystic nodule with a characteristic signal intensity will aid in the diagnosis of RCC and the selection of conservative management.     

Endodermal epithelial cyst in the prepontine cistern extending into the fourth ventricle--case report.

The authors report a case of epithelial cyst, which recurred 32 years after the initial surgical treatment. Computed tomography showed no abnormality, but magnetic resonance (MR) imaging clearly demonstrated a well-demarcated mass in the prepontine cistern, extending into the fourth ventricle. The lesion showed extreme hyperintensity compared with the surrounding brain on both the T1- and T2-weighted images. The ultrastructural features of the cyst suggested an endodermal origin. MR imaging and electron microscopy are essential for correct diagnosis and exact pathogenetic identification of intracranial cystic lesions.     

Intratumoral hemorrhage of cholesterol granuloma in the frontal bone showing rapid progressive symptoms: a case report

A 30-year-old man developed an exopthalmus in his right eye and diplopia at upward gaze those were progressive in two days. On admission, his upper eye lid in the right eye swelled and upward gaze was limited in the right eye. CT scan showed an osteolytic lesion in the right frontorbital bone. MR imaging showed a high signal tumor in both T1- and T2-weighted imaging with sharp margin and no enhancement. Right frontal craniotomy was performed and the cystic tumor consisting of old hematoma, and soft tissue surrounding the cyst was totally removed. The orbital roof had a large defect and tumor compressed periorbita. Neither communication with the frontal sinus nor mucosa with inflammation were seen. The postoperative course was uneventfull and pathological diagnosis was cholesterol granuloma with hematoma. Orbitofrontal bone is a rare site to have cholesterol granuloma. Most of them are asymptomatic. In our case, intratumoral hemorrhage caused compression on the perioribital, leading to a progressive mass sign. Preoperative differential diagnosis from other orbital tumors, such as epidermoid and lipoma was difficult.     

Spontaneously ruptured craniopharyngioma cyst without meningitic symptoms --two case reports

Two cases of spontaneous rupture of cystic craniopharyngioma without chemical meningitis are described. A 70-year-old woman complained of headache and visual field disturbance in July 1993. The tumor was extirpated in November 1993 and again in December 1996. After regular periodic follow-up evaluation, she was hospitalized for reoperation because of expansion of the cyst on magnetic resonance (MR) imaging in November 1998. However, preoperative MR imaging taken 8 weeks later revealed spontaneous reduction of the cyst. A 69-year-old woman noticed deteriorating vision and bitemporal hemianopsia in November 1998. The tumor was removed in December 1998, and 50.4 Gy postoperative radiotherapy was administered. MR imaging in May 2000 demonstrated an enlargement of the cyst, so she was hospitalized again for operation. However, preoperative MR imaging taken 7 weeks later showed spontaneous reduction of the cyst. Neither of the cases of cyst rupture were accompanied by symptoms of chemical meningitis. The signal intensity of the tumors on T1-weighted MR imaging declined after cyst reduction. Thereafter, the cysts increased in size again at 7 months and 5 months. Regular follow-up on MR imaging is necessary, since the cyst size can increase rapidly, even after spontaneous rupture.     

Clinical characteristics and surgical outcomes of spinal intramedullary ependymal cysts

Object

Intramedullary ependymal cysts are exceedingly rare lesions, and have been previously reported in the literature as case reports. The aim of this study was to discuss the clinical presentation and the outcomes of microsurgery for these benign lesions.

Methods

The authors retrospectively reviewed the records of ten patients who underwent microsurgery for intramedullary ependymal cysts. All patients had preoperative and postoperative magnetic resonance imaging. The surgical treatment included gross total resection and biopsy plus a cyst-subarachnoid shunt. The diagnosis of intramedullary ependymal cysts was based on radiological and pathological criteria. All patients were followed up, with a mean duration of 47.6 months.

Results

Intramedullary ependymal cysts were hypointense on T1-weighted images and hyperintense on T2-weighted images. Contrast-enhanced T1-weighted images showed no enhancement. Gross total resection was achieved in one case. Biopsy of the cyst wall plus cyst-subarachnoid shunt placement was achieved in nine cases. Long-term neurological function was improved in eight patients. No recurrence was observed on magnetic resonance imaging.

Conclusions

Ependymal cysts should be considered in the differential diagnosis of intramedullary cysts. For symptomatic patients, early surgery should be performed before neurological deficits deteriorate. Complete decompression and cyst-subarachnoid shunt placement is the optimal treatment and the outcome may be favorable.