Lymphoepithelial cysts of the pancreas: demonstration of lipid component using CT and MRI

We present two cases of surgically proven lymphoepithelial cyst (LEC) of the pancreas that had a lipid component visualized by CT and MRI. Identification of this component in a pancreatic cystic lesion is a key to favor the diagnosis of LEC or splenic epidermoid cyst over other cystic lesions when the lesion is noted in an elderly patient.     

Occult uterine rupture: role of ultrasonography

Neurenteric cysts are cystic masses lined by a columnar epithelium of endodermal origin. They are rare in the central nervous system. We report two neurenteric cysts in the posterior cranial fossa and describe their neuroradiological features. The lesions were of low density on CT and more accurately delineated on MRI. They gave the same signal as cerebrospinal fluid on all sequences. There was no contrast enhancement.     

Cystic mesothelioma of the peritoneum

We report a case of cystic mesothelioma of the peritoneum (CMP), a rare tumor. The magnetic resonance imaging (MRI) findings and the histochemical features were studied. The patient was an 18-year-old women who presented with upper abdominal pain. Abdominal ultrasonography and computed tomography showed a well defined cystic mass with a solid papillary projection in its lumen. MRI of the cyst showed high intensity on T2- and proton weighted images and low intensity on T1-weighted images, and the solid projection showed low intensity on T2- and proton-weighted images and slight low intensity on T1-weighted images, on which it was well enhanced. The lesion was suspected to be a benign cyst, such as a hemangioma, lymphangioma, or a splenic or pancreatic cyst. Complete surgical resection was performed. The resected specimen consisted of a unilocular cystic mass, with a solid projection, weighing 260 g and measuring 10 cm in diameter. The final diagnosis, arrived at by histopathological examination, was low-grade malignant CMP. The tumor cells were strongly positive for keratin, weakly positive for vimentin, and negative for epithelial membranous antigen. The patient is now well and symptom-free with no recurrence 19 months after operation. CMP is a rare tumor; only 12 cases have previously been reported in Japan.     

A case of macrocystic cervical neurinoma diagnosed by MRI with Gd-DTPA

The authors report a rare case of a large cystic cervical neurinoma. A 45-year-old female was admitted to our clinic because of motor weakness of the right upper extremity, numbness of the right fingers and right posterior cervical pain. Metrizamide CT myelography demonstrated the outline of a low density mass. MRI showed a mass revealing low signal intensity on T1-weighted image, high signal intensity on T2-weighted image and marginal enhancement on contrast image with Gd-DTPA. The mass which was diagnosed as cystic tumor, was located in the intradural extramedullary space between C4 to C5 segments. After C4 through C5 laminectomy, the tumor was found to originate from the C5 anterior motor root. The tumor consisted mostly of a cystic part with a very thin solid compartment beneath the capsule. Postoperative course of the patient was uneventful. Although spinal neurinoma is one of the most common spinal tumors, an almost completely degenerated large cystic spinal neurinoma is extremely rare. MRI with Gd-DTPA was useful for the diagnosis of the cystic neurinoma by clearly enhancing the margin of the tumor.     

Cystic meningioma: neuroradiological (MRI, CT) and macroscopic intraoperative appearance. A case report

Differential diagnosis of intracranial cystic meningiomas may present difficulties in about 10-15% of cases where anatomo-pathological alterations such as intratumoral necrosis, cystic cavity, hemorrhage or lipomatous infiltration are present. These alterations are responsible for an unusual radiological appearance which may suggest a false diagnosis. We describe a case of meningioma with a cystic appearance in which MRI was more helpful than CT, because it suggested an extra-axial meningiomatous lesion and thus allowed more precise surgical planning.     

A case of mediastinal seminoma undergoing extremely cystic degeneration

A-25-year-old male had an abnormal shadow on chest X-ray. CT and MRI films revealed a cystic lesion, with irregular nodules in the right anterior mediastinum. A cystic teratoma was suggested. Antero-axillary thoracotomy revealed a cystic lesion originating from the right lobe of the thymus. The lesion was extirpated, along with the right lobe of the thymus. The cystic part of the lesion, filled with brown fluid, was occupied by several masses originating from the wall of the tumor. Pathologically, the lesion was diagnosed as a seminoma undergoing cystic degeneration. The patient was given post-operative irradiation of 20Gy. No apparent recurrence has been detected 33 months after surgery. Mediastinal seminomas generally occur as a solid tumor consisting of stroma and tumor cells. However, this case report suggests that mediastinal seminomas may undergo extremely cystic degeneration.     

Cystic meningiomas resembling glial tumors

BACKGROUND: Meningiomas can be associated with peripheral or intratumoral cysts. Meningiomas with intratumoral cysts, also called "true cystic" meningiomas, are rare and can frequently be confused with glial or metastatic tumors. METHODS: We report three cases of "true cystic" meningiomas and discuss the preoperative evaluation, etiology, and surgical treatment of these cystic lesions with reference to the literature. RESULTS: Magnetic resonance imaging (MRI) and computed tomography (CT) studies usually display a cystic lesion close to the dura with or without enhancement of the cyst wall. Multiplanar MRI scans are very useful to show the presence of a solid tumor or some dural enhancement. Some cases of "true cystic" meningiomas however, are still erroneously preoperatively diagnosed. Complete surgical removal of the tumors and of the entire cyst wall was performed in our cases. Despite the absence of a typical ring enhancement of the cystic lesion in two cases, histopathologic studies displayed the presence of tumor cells on the cyst wall of both cases. CONCLUSIONS: Tumor cells can be present on the cyst wall and therefore can be one of the causes of tumor recurrence if not totally removed. Accurate preoperative radiologic diagnosis (multiplanar MR images) and intraoperative histopathologic studies are fundamental in that they will definitely influence the surgical strategy and outcome.     

Atraumatic osteolysis of the distal clavicle: MR findings

OBJECTIVE: The purpose of this study was to describe the MRI appearance in atraumatic osteolysis of the distal clavicle (AODC). MATERIALS AND METHODS: We retrospectively evaluated MRI, medical records, ancillary diagnostic imaging studies and clinical course in five men and two women (mean age, 39 years) in whom the final clinical diagnosis of AODC was established. None of the patients had significant shoulder injury, but all participated in activities involving repetitive strain of the acromioclavicular (AC) joint. In three of these patients, we performed follow-up MRI (ranging from 5 1/2 to 15 months after the initial MRI). RESULTS: In all seven patients, signal intensity changes within the intramedullary portion of the distal clavicle on MRI were consistent with diffuse bone marrow edema. Marrow edema was most conspicuous on STIR imaging and occasionally could be misinterpreted as normal marrow signal patterns on spin-echo imaging. Cortical thinning or irregularity of the distal clavicle was seen in six cases and tiny subchondral cysts were seen in three, corresponding to subtle cystic changes on shoulder radiography. Limited bone scans obtained in two patients showed markedly increased uptake of radiotracer at the distal clavicle and AC joint. Histologic examination in one case showed disruption of articular cartilage, subchondral cysts, and metaplastic bone formation with increased osteoclastic activity. Follow-up MRI in three patients who were asymptomatic following conservative therapy showed normalization of marrow signal intensity. CONCLUSION: Atraumatic osteolysis of the distal clavicle is a relatively uncommon but important cause of shoulder pain. Particularly when the clinical history is suggestive of repetitive AC joint stress, MRI of the distal clavicle should be examined closely for marrow edema, cortical irregularity, and cystic changes. Such abnormalities may be especially conspicuous when STIR imaging techniques are used.     

Cerebral amyloid angiopathy: prospects for clinical diagnosis and treatment

The MRI features of small renal cell carcinomas (RCCs) were retrospectively reviewed and correlated with histology in 24 patients. MRI features on both T1- and T2-weighted images were classified into hypointensity, isointensity, and hyperintensity. Each tumor was pathologically classified into four types: alveolar, papillary, tubular, and cystic. These findings were correlated with MR signal intensities. Alveolar tumors showed hypointensity to isointensity on T1-weighted image and isointensity to hyperintensity on T2-weighted image. In contrast, all papillary tumors showed hypointensity on T2-weighted image. Four of six tumors with hypointensity on T2-weighted image were caused by hemosiderin deposition, hemorrhage, and necrosis. However, there were two papillary RCCs that showed hypointensity on T2-weighted image despite no hemosiderin deposition and no hemorrhage. We conclude that papillary RCC is associated with T2-hypointense appearance as well as hemosiderin deposition, hemorrhage, and necrosis.     

Twenty years of research on B-cell chronic lymphocytic leukemia

The typical MRI features of the most common pancreatic diseases, such as pancreatitis and adenocarcinoma of the pancreas, have been established. However, even in these common pancreatic disorders, MRI correlation with the underlying pathology is limited for clinical reasons. We emphasize MR-pathological correlation of inflammatory and neoplastic pancreatic changes, including pancreatitis, adenocarcinoma, acinar cell carcinoma, rare cystic and solid pancreatic neoplasms, and islet cell tumors. By highlighting the correlation of key pathological features with MR findings, a better understanding of the MR appearance of pancreatic pathology can be provided. In addition, MRI may prove a powerful tool in detection and characterization of pancreatic tumors.     

Cystic meningiomas: unusual forms of intracranial neoplasms

OBJECTIVE: We report eight patients with cystic intracranial meningiomas to outline the neuroimaging spectrum of this unusual form of intracranial tumors. METHODS: Both CT and MRI were equally effective for the detection of peritumoral or intratumoral cystic lesions. However, neuroimaging findings were nonspecific and did not allow a correct preoperative diagnosis in most cases. CONCLUSIONS: Only a high index of suspicion permits the neurosurgeon a proper recognition of cystic meningiomas and its differentiation from the more common and malignant gliomas.     

Magnetic resonance imaging of soft tissue and cystic masses about the knee

Magnetic resonance imaging (MRI) of the knee is the most frequently performed joint MRI examination. The use of MRI has revolutionized assessment of both intra-articular and periarticular musculoskeletal masses about the knee and has largely supplanted other radiologic methods of evaluation. The purpose of this article is to review the MRI appearance of the numerous types of soft-tissue and cystic masses that arise about the knee.     

The response of adenoid cystic carcinoma to tamoxifen

Adenoid cystic carcinoma of the parotid gland often recurs locally, or metastases develop, after initial treatment with surgery and radiotherapy. We report a patient with an inoperable local recurrence of previously irradiated adenoid cystic carcinoma, who was treated with tamoxifen, an oestrogen receptor antagonist. After 18 months of treatment with tamoxifen, MRI showed a partial response, and further clinical progression of the disease was halted.     

High-resolution contrast-enhanced MRI of the uterus with a phased-array multicoil

High-resolution contrast-enhanced dynamic MRI of the uterus can be performed with the combination of a phased-array multicoil and fast GE techniques. This technique can improve the ability to visualize normal anatomy of the uterus and periuterine tissues, including vascular structures and pelvic ligaments, and to detect pathologic processes of the uterus and determine their extent.     

Magnetic resonance imaging in the diagnosis of jejunal leiomyoblastoma

We report a case of large leiomyoblastoma of the jejunum. The sagittal views in pre-operative magnetic resonance imaging (MRI) indicated that a cystic tumor with solid component was present, sequential from the small bowel. We suspected a smooth muscle tumor of the small bowel, but did not rule out the malignancy. The operative diagnosis was smooth muscle tumor of the proximal jejunum, and partial resection of the small bowel was performed. The pathological examination revealed benign leiomyoblastoma of the jejunum without metastasis. MRI contributed to the pre-operative diagnosis of the origin of this rare tumor, in a non-invasive fashion.     

Hyperreactio luteinalis in pregnancy

We report on the extremely rare case of ovarian overstimulation in a single pregnancy without prior hormonal stimulation therapy. During the 26th week of gestation ultrasound examination showed a 103 x 57 x 78 mm polycystic tumour with echogenic structures inside the cysts, located behind the uterus. Further management consisted of laparotomy with partial resection of a cystic part of the left ovary. Frozen section examination confirmed the diagnosis of hyperreactio luteinalis and excluded malignancy. To avoid torsion of the ovaries, cysts from both sides were aspirated. On day 8 and 18 after surgery, sonography revealed no pathological finding. In the 40th week of gestation, a healthy baby was delivered. The possibility of a hyperreactio luteinalis has to be kept in mind, when cystic solid tumours of the ovaries are diagnosed during pregnancy. A conservative management is appropriate, because a normal spontaneous remission occurs after delivery.     

Cystic renal cell carcinoma: report of four cases

We report 4 cases of cystic renal cell carcinoma (RCC), one of simple cystic type (case 2) and three of multilocular cystic type (case 1, 3 and 4). All cases were diagnosed preoperatively as malignant neoplasms on the basis of radiological examinations, including CT scan and angiography. Pathological examination revealed that intrinsic cystic growth was the probable cause in the three cases of multilocular cystic RCC, while the simple cystic case was probably caused by secondary cyst formation as a result of tumor necrosis. Radical nephrectomy was performed in cases 1, 2 and 4 and partial nephrectomy in case 3. We recommend nephron-sparing surgery as an option in the management of select cystic RCC, given that many cystic RCCs are low grade and enveloped by distinct pseudocapsules with fibrous tissues.     

Cerebellar deficient folia (cdf): a new mutation on mouse chromosome 6

OBJECTIVE: To discuss the case of an 8-yr-old boy with an aneurysmal bone cyst of the right proximal humerus, including the features imaged on plain film radiography, computed tomography (CT), magnetic resonance imaging (MRI), including spin echo and fast field echo imaging. CLINICAL FEATURES: The patient suffered for 1 yr from intermittent but progressive pain in his right upper arm and shoulder area. There was no history of trauma or known systemic disease. There was decreased range of motion in abduction of the glenohumeral joint and pain on focal pressure along the deltoid muscle. A complete imaging evaluation consisting of plain film radiography, CT and MRI was performed, which revealed the classical imaging features of an aneurysmal bone cyst. An additional cystic lesion was detected by the MRI that was not appreciated on the plain films or CT. INTERVENTION AND OUTCOME: The patient was referred for biopsy to confirm the preliminary diagnosis of aneurysmal bone cyst. No treatment was instituted. CONCLUSION: Evaluation of aneurysmal bone cyst may be completed with CT scanning and more specifically with MRI MRI coronal T2, weighted images are advantageous for visualization of the main cystic lesion and any additional cysts. Fast field echo images show a better contrast between the cyst and bone marrow with extension of the cyst into the epiphysis as evident in this case. Follow-up studies revealed complete healing of the cyst with only residual densities in the humeral metaphyseal area.     

Prenatal diagnosis of fetal nuchal cystic hygroma in 22 cases

OBJECTIVE: To investigate the early diagnosis and prognosis of fetal nuchal cystic hygroma. METHODS: 72 cases of fetal nuchal cystic hygroma diagnosed in uterus were analyzed retrospectively. RESULTS: Most of the cases were diagnosed by B ultrasound between 15-26 gestational weeks. 55.9% the multipara had abnormal pregnant history, and 40% (4/10) of fetuses with karyotype performed had chrosome abnormality. Except for fetal deaths and induced abortions, 3 cases had term deliveries: one neonatal death, one was born with hygroma of 5.9 cm x 3.7 cm and transferred for surgery, and the other one with hygroma disappeared at the 37th week and baby was born at 40 week with normal appearance. CONCLUSIONS: This disease is one of common fetal morphological abnormalities. Few may recover spontaneously but most have poor outcomes.     

Diffuse cystic malformation and neoplasia-associated cystic formation in the stomach. Endosonographic features and diagnosis of tumor depth

We have evaluated the endoscopic ultrasonography (EUS) features of cystic malformation of the stomach and the depth of associated neoplasia. We included 15 patients with multiple cystic components identified on EUS: 6 patients with multiple cysts restricted focally to gastric neoplasia and 9 patients with diffusely distributed cysts. We categorized the former findings as focal cystic malformation (FCM), and the latter as diffuse cystic malformation (DCM) of the stomach and reviewed the endosonographic features. Both FCM and DCM tended to show male preponderance and develop in older patients. Cystic changes in FCM extended from the neoplastic lesion to the submucosa regardless of the location in the stomach. Diffuse cystic malformation was located predominantly in the gastric body and mainly was shown as the thickened submucosa and/or deep mucosa with multiple cystic components. The boundary between the mucosal layer or the tumor echo and the submucosal layer was indistinct in eight patients, which led to a lower accuracy in EUS diagnosis of tumor depth. Diffuse cystic malformation has characteristic EUS features and occasionally is accompanied by gastric neoplasia. Endoscopic ultrasonography is inaccurate in determining tumor depth when multiple submucosal cysts are present.