Multiple epidermoid cysts located in the pineal and extracranial regions treated by neuroendoscopy

A 22-year-old woman presented with a rare case of multiple epidermoid cysts located in the pineal and extracranial regions. Magnetic resonance (MR) imaging showed a lesion in the pineal region as hypointense on the T(1)-weighted image and hyperintense on the T(2)-weighted image, without enhancement. Neuroendoscopic treatment was performed under a diagnosis of pineal cyst. However, the cyst wall was too thick to perforate, although third ventriculostomy was performed. Diffusion-weighted MR imaging demonstrated the lesions in the pineal and extracranial regions as marked hyperintensity. The diagnosis was epidermoid cyst. Subsequently, neuroendoscopic treatment of the pineal epidermoid cyst was performed. Careful preoperative diagnosis of epidermoid cysts based on diffusion-weighted MR imaging is required.     

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.     

Endoscopic fenestration of posterior fossa arachnoid cyst for the treatment of presyrinx myelopathy--case report

A 32-year-old man presented with an arachnoid cyst of the posterior fossa manifesting as cervical syringomyelic myelopathy. Magnetic resonance (MR) imaging demonstrated edematous enlargement and T2 prolongation of the cervical spinal cord, indicating a "presyrinx" state. MR imaging showed the inferior wall of the cyst, which disturbed cerebrospinal fluid (CSF) pulsatile movement between the intraspinal and intracranial subarachnoid spaces. The cyst wall was fenestrated with a neuroendoscope. The presyrinx state and the CSF movement improved. Posterior fossa arachnoid cyst, as well as Chiari malformation, can cause CSF flow disturbance at the craniocervical junction and syringomyelia. Endoscopic fenestration is less invasive than foramen magnum decompression and should be the procedure of choice.     

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.     

Spinal intramedullary ependymal cyst. Report of three cases

Three cases of spinal intramedullary ependymal cyst, two at the thoracolumbar junction and one in the cervical spinal cord, are reported in women in their fifth to seventh decades. Neurological signs and symptoms were extremity dysesthesias, paresthesias, and weakness. Plain cervical and lumbothoracic x-ray films were normal for the patients' age. Magnetic resonance (MR) imaging demonstrated a rounded cystic intramedullary mass at the thoracolumbar junction in two cases and at C3-7 in one case. The signal intensity of the cyst contents approximated that of cerebrospinal fluid on T1- and T2-weighted images. Upon administration of gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA), MR imaging showed no enhancement in the cyst wall or cavity. Myelotomy and cyst drainage were performed in each case, and the neurological status of each patient improved. The lining of the cyst was biopsied in one of the three patients undergoing surgery and was composed of a single layer of cuboidal cells supported by glial tissue. Periodic acid-Schiff staining of the tissue did not reveal a basement membrane. The findings in these cases suggest that the Gd-DTPA-enhanced MR imaging appearance of intramedullary spinal ependymal cyst is consistent and allows for accurate preoperative diagnosis with or without biopsy.     

膝关节髌下脂肪垫区肿瘤的MRI诊断

目的:研究发生于膝关节髌下脂肪垫区肿瘤或肿瘤样病变及其MRI表现。方法:回顾性研究14例经手术病理证实的膝关节髌下脂肪垫区的肿瘤或肿瘤样病变的MRI表现。分析病变的MRI形态、平扫与增强的信号特点。结果:14例15个病灶,滑膜腱鞘巨细胞瘤7例,肿块T1WI呈等信号或稍高信号,T2WI呈等信号5例,高信号肿块内有含铁血黄素低信号灶2例,轻度或不强化。髌下脂肪垫内海绵状血管瘤2例,T1WI呈等信号,T2WI呈显著高信号,明显强化。囊肿4例,T1WI低信号,T2WI呈高信号,无强化。滑膜纤维脂肪瘤2例,T1WI呈等或高信号,T2WI呈高信号。结论:膝关节髌下脂肪垫区可发生多种肿瘤或肿瘤样病变,以滑膜腱鞘巨细胞瘤、海绵状血管瘤及滑膜囊肿多见。MRI表现具有一定的特征性,不失为术前定性诊断的有效方法。     

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.     

Colloid (enterogenous) cyst in the frontal lobe

A 60-year-old man presented with a left frontal mass lesion incidentally detected at a health check without apparent symptoms. Computed tomography revealed the lesion as homogeneous high density and magnetic resonance (MR) imaging showed the lesion as hyperintense on T(1)-weighted images, isointense on T(2)-weighted images, and hypointense on diffusion-weighted images. T(1)-weighted MR images with gadolinium showed no enhancement of the mass lesion. Cerebral angiography revealed an avascular area around the left frontal lesion. Total removal of the lesion was achieved through a craniotomy without complications. Histological, immunohistochemical, and electron microscopy examinations established the definite diagnosis of colloid cyst.     

Hypophysitis caused by Rathke's cleft cyst. Case report

A 62-year-old woman presented with general malaise persisting for 2 months and narrowing of her visual field. T1-weighted magnetic resonance (MR) imaging showed swelling of the pituitary gland and stalk, and a homogeneous isointense intra- and suprasellar mass enhanced by gadolinium. During outpatient follow up, her condition deteriorated rapidly and she developed diabetes insipidus and panhypopituitarism. T1-weighted MR imaging demonstrated shrinkage of the lesion and disappearance of the central hypointense area indicating the cyst cavity, especially in the pituitary stalk. She underwent surgical exploration via the transsphenoidal approach under a provisional diagnosis of lymphocytic hypophysitis. Histological examination revealed ciliated columnar cells and squamous metaplasia on the inner surface of the cyst wall, with many foamy cells, infiltration by many lymphoid cells and some eosinophils, and fibrosis in the adenohypophysitis and inflammatory hypophysitis in the anterior and posterior pituitary gland. The present neuroimaging findings of cyst shrinkage associated with rapid clinical deterioration strongly support the suggestion that rupture of Rathke's cleft cyst causes inflammatory hypophysitis.     

Stereotactic radiosurgery and vestibular schwannoma: hydrocephalus associated with the development of a secondary arachnoid cyst: a report of two cases and review of the literature

Stereotactic radiosurgery for vesibular schwannoma requires long-term follow-up with complete MR imaging. We report two cases of a large secondary arachnoid cyst developing in the cerebellopontine angle following stereotactic radiosurgery. In one case this was associated with progressive ventriculomegaly and the onset of symptomatic hydrocephalus requiring emergency treatment. The second patient had ventriculomegaly at diagnosis, but developed an arachnoid cyst following treatment. Although both arachnoid cysts and hydrocephalus may also occur spontaneously in patients with vestibular schwanomma, the incidence is higher after stereotactic radiosurgery. As both complications may be associated with sudden clinical deterioration, follow-up with full cranial T1 and T2 weighted MR imaging is required to reveal these complications, in addition to assessing tumour response.     

Thoracic intradural arachnoid cyst associated with surgical removal of epidural hematoma--case report

A 54-year-old woman presented with a very rare association of spinal intradural arachnoid cyst and spinal epidural hematoma manifesting as paraparesis subsequent to severe back pain. Magnetic resonance (MR) imaging disclosed a ventral epidural hematoma extending from the T-4 to T-6 levels and compressing the spinal cord ventrally. Emergent surgical evacuation of the epidural hematoma was carried out 22 hours after the onset. MR imaging obtained 2 days after surgery showed enlargement of the dorsal subarachnoid space at the T-3 to T-8 levels. The patient could walk independently within 6 months after discharge, but paraparesis recurred 3 years after surgery. MR imaging showed formation of an intradural arachnoid cyst, which compressed the spinal cord dorsally. She underwent arachnoid cystectomy, and recovered ambulation postoperatively. This case of intradural arachnoid cyst of the thoracic spine which appeared after surgical removal of an epidural hematoma at the same spinal level indicates some association between the epidural hematoma and the arachnoid cyst.     

Intraoperative MR imaging in a case of a cervical spinal cord lesion

The aim of this article is to describe the feasibility of performing intraoperative MR imaging in patients with spinal cord lesions and the potential value of this technique. The authors report a case involving a 28-year-old man who presented with chronic cervical pain and pain along the ulnar side of the forearms during neck flexion. Findings on clinical examination were normal, but MR imaging revealed a multicystic cervical spinal cord lesion. Surgery was undertaken to open the cysts, evacuate old blood, and search for pathological tissue. Intraoperative MR imaging showed that the caudal cyst was not opened, and surgery was therefore continued. The caudal cyst was fenestrated and a suspected small cavernous malformation was removed. Electrophysiological monitoring was performed both before and after the intraoperative MR imaging. The use of intraoperative MR imaging changed the strategy of the procedure and helped the surgeon to safely enter all the cysts in the cervical cord.     

A case report; ganglion cyst of a cervical facet joint

Ganglion or synovial cyst typically occurs in peripheral joints and tendon sheaths such as elbow joint or wrist joint, but rarely in the spinal facet joint. From reported cases the most common site involved seems to be the lumbar facet joint. Only three cases of cervical ganglion or synovial cyst have so far been found in the literature. A case of cervical ganglion cyst was reported. The patient was a 2-year-old boy who was found to have a tumor in the midline of the nape. He had no history of trauma. Neurological and physical examination revealed no abnormalities. On CT scan a round low dense lesion with clear margin was found in the nape. Enhanced CT scan showed ring-like enhancement. Magnetic resonance (MR) imaging showed a well defined lesion of high intensity on T1- and T2-weighted images. At operation, the lesion was found to form a cyst containing old hematoma, and the cyst wall seemed to be fixed to the cervical spinal facet joint. The tumor was histologically diagnosed as ganglion cyst.     

Surgical strategy for intracranial endodermal cyst--case report

Two cases of endodermal cyst of the posterior fossa are reported. A 12-year-old girl presented with severe headache and vomiting caused by increased intracranial pressure. Computed tomography and magnetic resonance (MR) imaging showed a cystic mass occupying the ambient and quadrigeminal cisterns. A 65-year-old woman presented with dizziness, and MR imaging revealed a cystic mass in the posterior fossa. The two patients underwent surgery for decompression and resection of the cyst. Surgical specimens of the cyst walls consisted of a single layer of ciliated columnar epithelium. The diagnoses were endodermal cyst. The optimal surgical goal is total resection of the cyst wall, but the cyst wall sometimes tightly adheres to the adjacent nerves, vessels, and vital structures. The cyst must communicate adequately with the surrounding cerebrospinal fluid space, and a newly closed cyst space must be avoided, by the widest possible resection of the cyst wall.     

Magnetic resonance imaging of the thyroid, thymus, and parathyroid glands

Magnetic resonance (MR) images of the neck were obtained in 16 patients with use of a variety of spin echo and inversion recovery pulse sequences. Anatomic resolution was best with high-resolution spin echo images obtained with the pulse sequence repetition rate equal to 2.0 seconds and the echo delay equal to 28 msec because this imaging technique offered excellent contrast between normal tissues and had the highest signal noise ratio. The spatial resolution of MR was nearly as good as state of the art computerized tomography (CT). However, streak artifacts caused by motion and x-ray beam hardening often limited CT but did not affect MR. Tumors and lymph nodes were more easily differentiated from muscle and blood vessels with MR than with CT because of the superior soft-tissue contrast of MR. Tissue characterization allowed MR differentiation of thyroid nodules, thyroid cysts, and parathyroid tumors from normal thyroid tissue. Thyroid cyst fluid had the greatest water content and longest T1 and T2 relaxation times of all tissues studied. However, nonspecifically increased T1 and T2 relaxation times overlapped for a variety of neoplastic and inflammatory conditions. With further experience, MR imaging is likely to become a useful technique for the evaluation of neck masses.     

Recurrent intrasellar arachnoid cyst

A 48-year-old man presented with complaints of decreased visual acuity persisting for 6 weeks in December 1997. Neurological examination demonstrated defects in the superior bitemporal visual field and bilateral optic atrophy. Computed tomography and magnetic resonance (MR) imaging showed an intrasellar cystic lesion. The cyst wall was excised via a transsphenoidal approach. The diagnosis was intrasellar arachnoid cyst. The sellar floor was reconstructed after packing fat in the sellar turcica. The visual complaint improved, but he was lost to follow up. Four years later, he was re-admitted complaining of decreased visual acuity. Superior bilateral field defects were found. MR imaging revealed recurrence of the intrasellar arachnoid cyst. The cyst wall was excised through a craniotomy. The visual acuity and the visual field defects gradually improved. Intrasellar arachnoid cyst may recur after transsphenoidal surgery, so long-term follow up is necessary after excision of the intrasellar cyst wall.     

Spinal arachnoid cyst causing paraplegia following skull base surgery

A 40-year-old woman presented with a right petroclival meningioma compressing the brainstem and manifesting as a 6-month history of headache and gait difficulty. The patient underwent subtotal removal of the tumor via an anterior transpetrosal approach. The postoperative course was complicated by cerebrospinal fluid rhinorrhea, bacterial meningitis, and acute hemorrhagic rectal ulcer. The patient was discharged home in good condition after prolonged medical treatment. Four months after the surgery, the patient noted recurrence of gait difficulty. Magnetic resonance (MR) imaging of the brain showed enlargement of the ventricles and no residual brainstem compression. A ventriculoperitoneal shunt was placed, but the symptoms were unchanged. The shunt was removed 2 months later because of infection. The patient's gait gradually deteriorated, although repeat brain MR imaging showed no significant increase in ventricular size. Ten months after the initial surgery she became paraplegic. MR imaging of the thoracic spine revealed a large arachnoid cyst extending from C-6 to T-6. The patient underwent T2-4 laminectomy, partial removal of the cyst wall, and duraplasty, but no clinical improvement was observed. Preexisting long-tract signs and coincidental hydrocephalus confused the neurological findings and delayed detection of the spinal lesion in this case. Neurosurgeons should be alert to the possibilities of insidious spinal lesion if the patient has progressive neurological disorder which does not match the known cranial lesion.     

Asymptomatic huge congenital arachnoid cyst successfully treated by endoscopic surgery--case report

A female neonate was the first child of a 30-year-old mother, with unremarkable medical history. Prenatal ultrasonography performed at 36 weeks of gestation suggested intracranial mass lesion. The baby was delivered by cesarean section at 41 weeks of gestation because of bradycardia and asphyxia. The birth weight, height, and head circumference were within the normal ranges with soft fontanels. Congenital anomaly was not observed with normal neurological findings. She was referred to our department at age 5 months. Physical examination revealed normal developmental milestones and intact endocrinological function without macrocephaly. Cerebral magnetic resonance (MR) imaging revealed a unilocular huge cyst appearing as homogeneously hypointense on T(1)- and hyperintense on T(2)-weighted images, and extending into the basal, suprasellar, ambient, quadrigeminal, interpeduncular, prepontine, right cerebellopontine angle, and premedullary cisterns. The pituitary stalk was markedly stretched and displaced ventrally, and the brainstem was displaced dorsally by the cyst. No other brain anomalies, dysgenesis of the corpus callosum, or ventriculomegaly were recognized. Neuroendoscopic cystocisternostomy was performed to form a communication between the cyst cavity and premedullary cistern. Pressurized watery fluid was released on puncturing the cyst wall which consisted of transparent membrane. Surveillance MR imaging at 2 and 9 months after the surgery revealed remarkable regression without regrowth of the cyst. She remained in good condition and showed normal development during the follow up for 1 year 9 months. Less invasive prophylactic surgery using the neuroendoscope may be beneficial for carefully selected cases of asymptomatic neonatal arachnoid cysts.     

Renal structure in early autosomal-dominant polycystic kidney disease (ADPKD): The Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) cohort

BACKGROUND: Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by gradual renal enlargement and cyst growth prior to loss of renal function. Standard radiographic imaging has not provided the resolution and accuracy necessary to detect small changes in renal volume or to reliably measure renal cyst volumes. The Consortium for Radiologic Imaging Studies in Polycystic Kidney Disease (CRISP) is longitudinally observing ADPKD individuals using high-resolution magnetic resonance (MR) imaging to determine if change in renal and cyst volumes can be detected over a short period of time, and if they correlate with decline in renal function early in disease. METHODS: Standardization studies were conducted in phantoms and four subjects at each participating clinical center. After, in the full-scale protocol, healthy ADPKD individuals 15 to 45 years old with creatinine clearance>70 mL/min underwent standardized MR renal imaging, renal iothalamate clearance, comprehensive clinical evaluation, and determination of 24-hour urinary albumin and electrolyte excretion. Stereology was used from T1-weighted images to quantify renal volume, and region-growing thresholding was used from T2-weighted images to determine cyst volume. Renal structures were evaluated in relation to demographic, clinical, and biochemical variables using means/medians, standard deviations, and Pearson correlations. RESULTS: Reliability coefficients for MR renal and cyst volume measurements in phantoms were 99.9% and 89.2%, respectively. In the full-scale protocol, 241 ADPKD individuals (145 women and 96 men) were enrolled. Total renal, cyst, and % cyst volume were significantly greater in each decade group. Hypertensive individuals demonstrated greater renal, cyst, and % cyst volume than normotensive subjects. Age-adjusted renal (r = -0.31, P < 0.0001), cyst (r = -0.36, P < 0.0001), and % cyst volume (r = -0.35, P < 0.0001) were inversely related to glomerular filtration rate (GFR). Age-adjusted renal volume (r = 0.42, P < 0.0001), cystic (r = 0.39, P < 0.0001, and % cyst volume (r = 0.41, P < 0.0001) were related with urinary albumin excretion. CONCLUSION: MR measures of renal and cyst volume are reliable and accurate in patients with ADPKD. ADPKD is characterized by significant cystic involvement that increases with age. Structure (renal and cyst volume) and function (GFR) are inversely related and directly related with the presence of hypertension and urinary albumin excretion in individuals with normal renal function.