Neurosarcoidosis: findings in MRI

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. Neurologic manifestations occur usually as a part of the spectrum of the systemic disease. The aim of this retrospective study was to evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of patients with neurosarcoidosis (NS). Seven patients with sarcoidosis could be included into the study. All patients had neurological symptoms and were evaluated with MRI revealing a wide spectrum of findings: periventricular and white matter lesions, multiple or solitary supra- and infratentorial brain lesions, leptomeningeal enhancement, involvement of brain nerves and intramedullar lesions. These findings are not specific for sarcoidosis and must be considered with the clinical course of the patient in arriving at the correct diagnosis.     

Imaging of blunt chest trauma

In western European countries most blunt chest traumas are associated with motor vehicle and sport-related accidents. In Switzerland, 39 of 10,000 inhabitants were involved and severely injured in road accidents in 1998. Fifty two percent of them suffered from blunt chest trauma. According to the Swiss Federal Office of Statistics, traumas represented in men the fourth major cause of death (4 %) after cardiovascular disease (38 %), cancer (28 %), and respiratory disease (7 %) in 1998. The outcome of chest trauma patients is determined mainly by the severity of the lesions, the prompt appropriate treatment delivered on the scene of the accident, the time needed to transport the patient to a trauma center, and the immediate recognition of the lesions by a trained emergency team. Other determining factors include age as well as coexisting cardiac, pulmonary, and renal diseases. Our purpose was to review the wide spectrum of pathologies related to blunt chest trauma involving the chest wall, pleura, lungs, trachea and bronchi, aorta, aortic arch vessels, and diaphragm. A particular focus on the diagnostic impact of CT is demonstrated. Received: 29 November 1999; Accepted: 28 January 2000     

Spinal cord magnetic resonance imaging in suspected multiple sclerosis

We examined the value of spinal cord magnetic resonance imaging (MRI) in the diagnostic work-up of multiple sclerosis (MS). Forty patients suspected of having MS were examined within 24 months after the start of symptoms. Disability was assessed, and symptoms were categorized as either brain or spinal cord. Work-up further included cerebrospinal fluid analysis and standard proton-density, T2-, and T1-weighted gadolinium-enhanced brain and spinal cord MRI. Patients were categorized as either clinically definite MS (n = 13), laboratory-supported definite MS (n = 14), or clinically probable MS (n = 4); four patients had clinically probable MS, and in nine MS was suspected. Spinal cord abnormalities were found in 35 of 40 patients (87.5 %), consisting of focal lesions in 31, only diffuse abnormalities in two, and both in two. Asymptomatic spinal cord lesions occurred in six patients. All patients with diffuse spinal cord abnormality had clear spinal cord symptoms and a primary progressive disease course. In clinically definite MS, the inclusion of spinal imaging increased the sensitivity of MRI to 100 %. Seven patients without a definite diagnosis had clinically isolated syndromes involving the spinal cord. Brain MRI was inconclusive, while all had focal spinal cord lesions which explained symptoms and ruled out other causes. Two other patients had atypical brain abnormalities suggesting ischemic/vascular disease. No spinal cord abnormalities were found, and during follow-up MS was ruled out. Spinal cord abnormalities are common in suspected MS, and may occur asymptomatic. Although diagnostic classification is seldom changed, spinal cord imaging increases diagnostic sensitivity of MRI in patients with suspected MS. In addition, patients with primary progressive MS may possibly be earlier diagnosed. Finally, differentiation with atypical lesions may be improved. Received: 21 April 1999; Revised: 3 August 1999; Accepted: 7 August 1999     

Vertebral sarcoidosis: imaging findings

Sarcoidosis is a multisystemic disease of unknown aetiology characterised by noncaseating granulomatous inflammation with varying presentation and prognosis. Osseous disease reported in 1–13 % of cases commonly involves hands and feet; however, vertebral sarcoidosis is rare. This report describes the radiologic, CT, MRI and radionuclide imaging findings of vertebral involvement of a case with sarcoidosis. Received: 28 January 1999; Revised: 14 April 1999; Accepted: 25 April 1999     

MR of sarcoidosis in the head and spine: spectrum of manifestations and radiographic response to steroid therapy.

PURPOSETo evaluate the role of MR in the diagnosis and treatment of patients with neurosarcoidosis.METHODSThe MR studies of 24 patients who satisfied stringent criteria for the diagnosis of sarcoid were retrospectively reviewed. All patients had signs and symptoms referable to the head and/or spine. The majority, 17 patients (71% of the total), were examined at least once with gadolinium enhancement. Fifteen of 24 patients (63%) underwent serial examinations during steroid therapy.RESULTSA wide spectrum of findings was noted: white matter and periventricular high signal intensity on long-repetition-time/long-echo-time sequences, mimicking multiple sclerosis (11 patients); leptomeningeal enhancement (11 patients); brain parenchymal mass (seven patients)--six demonstrated enhancement, one did not receive contrast; lacrimal gland mass (three patients); hydrocephalus (three patients); enlarged ventricles, apparently atrophic (one patient); periventricular enhancement (three patients); extraaxial mass, mimicking meningioma (two patients); chiasmal enhancement or swelling (one patient); enhancing nerve roots (two patients); enlarged pituitary stalk (two patients); pontine infarct (one patient); and enhancing parenchymal spinal cord mass (three patients). Partial or complete resolution of the radiographic abnormality occurred in 13 of 15 cases (87%), which paralleled clinical improvement. No response was detected in the remaining two. Abnormal enhancement was the finding that was most responsive to steroid therapy, with response seen in nine of 10 patients with leptomeningeal enhancement, in six of six patients with enhancing brain parenchymal masses, in three of three patients with enhancing cord masses, and in all three patients with periventricular enhancement.CONCLUSIONS1) MR shows a spectrum of protean central nervous system abnormalities associated with neurosarcoidosis. 2) This high sensitivity for associated abnormalities aids in differentiating central nervous system sarcoid from the many diseases that it can mimic. In particular, enhancement was a useful clue to the diagnosis in 15 of 17 cases in which it was used (88%). 3) MR demonstrates regression of central nervous system abnormalities during steroid therapy, in particular abnormal meningeal, periventricular, and parenchymal enhancement.     

Imaging of compressive vertebral haemangiomas

Compressive vertebral haemangiomas (VHs) are rare. Correct preoperative diagnosis is useful both for operative planning (since compressive VHs are extremely vascular lesions) and to allow preoperative embolisation. Numerous radiological signs for VHs have been described, but compressive VHs frequently have atypical features. In particular, magnetic resonance features are not well established. We present imaging features in three cases of compressive VH and review the imaging findings in an additional 106 previously published cases. Findings were typical in 52 of 80 plain film (65 %), 33 of 41 computed tomography (80 %) and 13 of 25 magnetic resonance examinations (52 %). The prevalence of previously described imaging features is reported. Awareness of the range of magnetic resonance features is important since this is frequently the initial investigation in patients presenting with symptoms of neural compression. Since computed tomography is typical in 80 % of cases, this is a useful confirmatory test if magnetic resonance features are suspicious but not diagnostic of compressive VH. Received: 6 August 1999; Revised: 4 November 1999; Accepted: 4 November 1999     

Acute presentation of cystic and mass-like lesions of the chest in children

A wide variety of cystic and mass-like lesions can occur in the chest of infants and children, but those that cause acute symptoms are often associated with pneumonia or infection of pre-existing congenital or developmental lung lesions. Pediatric chest masses can be classified by location, multiplicity, and the presence or absence of air-filled or fluid-filled cysts. Characteristic radiographic findings are diagnostic for some lesions, whereas others can appear quite similar radiographically. This article illustrates the common chest masses and cysts that present emergently in pediatric patients and discusses imaging approaches to the diagnosis of such lesions.     

Helical CT appearance of glomus tumor of the stomach

Glomus tumor occurs only rarely in the stomach. This benign intramural mass is located most frequently in the distal half of the stomach. We experienced two cases of glomus tumor of the stomach which were examined with helical CT and were confirmed pathologically. Both tumors were well-marginated solitary lesions, located in the gastric antrum. On the early-phase helical CT, an intact overlying mucosa was demonstrated in both cases, and both tumors showed a dense homogeneous contrast enhancement, which persisted to the delayed phase. Received: 26 January 1999; Revised: 18 May 1999; Accepted: 2 July 1999     

Technetium-99m hexamethylpropylene amine oxime leucocyte scintigraphy in the differential diagnosis of cerebral abscesses

The diagnosis of brain abscess is often difficult, as the clinical symptoms are not specific. Computed tomography (CT) and magnetic resonance imaging (MRI) are highly sensitive, but different cerebral lesions, especially neoplasms, can have the same ring-like contrast enhancement. Brain abscess is a severe illness requiring rapid diagnosis to choose the most appropriate therapy. Technetium-99m hexamethylpropylene amine oxime (HMPAO)-labelled leucocyte scintigraphy is commonly used to detect an inflammatory process. The aim of this study was to present the results obtained with leucocyte scintigraphy in 65 patients with intracranial mass lesions and clinical findings compatible to or suggestive of brain abscess. The final diagnosis, based on surgery, clinical findings and stereotatic puncture, was brain abscess in 17 patients, primary brain neoplasm in 22, brain metastasis in 16, lymphoma in 2, cysticercosis in 2, hematoma in 2 and cerebral infarction in 4. ^99mTc-HMPAO leucocyte scintigraphy was positive in all abscess cases. The scan was negative in the rest of the patients examined, with the exception of one lesion, which was finally diagnosed as a tumour (1 false-positive). All patients who did not have false-negative scans were treated with steroids. The sensitivity, specificity and diagnostic accuracy of leucocyte scintigraphy was 100%, 97.8% and 98.4%, respectively. In conclusion, in our experience, leucocyte scintigraphy is a valuable aid in the differential diagnosis between abscess and neoplasm. Received 25 April and in revised form 12 August 1999     

Renal carcinoma: diagnosis of venous invasion with Gd-enhanced MR venography

The aim of this study was to evaluate the usefulness of gadolinium-enhanced time-of-flight magnetic resonance venography (MRV) in the diagnosis of bland thrombosis/tumoral invasion in the preoperative assessment of renal cell carcinoma. Preoperative precontrast and enhanced GRE fast low-angle shot (FLASH) images of 36 patients with renal adenocarcinoma were reviewed and compared with pre- and post-contrast T1-weighted images. All patients underwent surgery, and MR findings were blindly and prospectively compared with surgical and pathologic data, considered the standard. Renal vein and vena cava were involved in 17 and 9 patients, respectively; right atrial extension was present in one patient. Precontrast spin-echo (SE) and FLASH images were 88 % sensitive and 100 % specific in the detection of venous involvement, respectively, and enhanced FLASH images 100 % sensitive and 96 % specific. The nature of thrombus (neoplastic or bland) was more accurately assessed (McNemar's, p < 0.05) with FLASH-enhanced MR images (sensitivity 89 %; specificity 96 %) than with SE and precontrast FLASH images (sensitivity 79 %; specificity 94 %). Our data suggest that use of Gd-enhanced MRV might improve preoperative assessment of vascular involvement in renal carcinoma. Received: 7 September 1999; Revised: 26 November 1999; Accepted: 26 November 1999     

Rheumatoid arthritis of the craniocervical region: assessment and characterization of inflammatory soft tissue proliferations with unenhanced and contrast-enhanced CT

The aim of this study was to depict and characterize inflammatory soft tissue proliferations caused by rheumatoid arthritis (RA) in the craniocervical region by unenhanced and contrast-enhanced CT. Computed tomography of the craniocervical region was performed in 35 patients in the axial plane before and after the i. v. administration of contrast material. According to the densities and contrast enhancement of the inflammatory soft tissue proliferations, four groups were classified. Ancillary findings, such as a compression of the dural sac or spinal cord, erosions of the bony structures, and atlantoaxial subluxation, were also evaluated. Inflammatory soft tissue proliferations were depicted in 28 of 35 patients and could be differentiated by unenhanced and contrast-enhanced CT according to the above defined criteria: effusion in 6 patients (17 %); hypervascular pannus in 8 (23 %); hypovascular pannus in 5 (14 %); and fibrous tissue in 9 patients (26 %). A compression of the dural sac was seen in 11 (31 %) patients; 3 of these had neurological symptoms. Erosions of the odontoid process were found in 20 (57 %) patients; 16 (80 %) of these also showed erosions of the atlas. Atlantoaxial subluxation was seen in 11 (31 %) patients. Inflammatory soft tissue proliferations in the craniocervical region caused by RA can be reliably demonstrated and classified by unenhanced and contrast-enhanced CT, which can differentiate between joint effusion and various forms of pannus and depict ancillary findings. Computed tomography is an alternative method for patients unable to undergo an MRI examination. Received: 4 October 1999; Revised: 7 March 2000; Accepted: 14 March 2000     

Flexible tantalum stents for the treatment of renovascular hypertension: a 10-year experience

The aim of this study was to determine long-term success of flexible tantalum stents for the treatment of ostial and truncal renal artery stenosis. Since 1989, flexible tantalum stents (type Strecker) were implanted in 34 patients (36 arteries, 25 ostial lesions, 11 truncal lesions) with uncontrollable renovascular hypertension, 9 of them in association with renal insufficiency. Stents were placed unilaterally in 32 patients, and bilaterally in 2 patients for the treatment of renal artery stenosis. Thirty-five of 36 lesions were atherosclerotic, including 5 recurrencies after previous percutaneous transluminal renal angioplasty (PTRA). One patient had Takayasu arteritis. Stents were implanted after unsuccessful PTRA of 11 truncal and 23 ostial lesions, and as a primary procedure in 2 ostial lesions. Follow-up examinations included blood pressure measurement, determination of serum creatinine level, color duplex sonography, or angiography. The technical success rate was 92 %. Technical failure included incorrect stent placement (1 of 36 lesions, 2.8 %), and stent dislocation (2 of 36 lesions, 5.6 %), and two stents were retrieved percutaneously. In one case of Takayasu arteritis, residual stenosis of 40 % was observed. After technically successful stent placement, 77 % of patients became normotensive with or without medication. In the remaining patients there was partial improvement with blood pressure between 140 and 180 mmHg. Renal function improved in 76 % of patients (completely in 3 of 8, 38 %; and partially in 3 of 8, 38 %). Primary patency rate including all stented lesions and initial technical failures was 82.4 % ± 6.8 (1 year) and 82.4 % ± 9.2 (3 years). After technically successful stent placement, patency rates were 89.9 ± 5.6 % (1 year), and 89.9 ± 7.6 % (3 years). For ostial lesions, primary patency rate was 87.9 ± 6.7 % (1 year) and 87.9 ± 9.2 % (3 years). Placement of flexible tantalum stents in renal arteries is technically demanding, especially in ostial lesions. Once placed successfully, stent patency rate is excellent. Received: 8 December 1999; Accepted: 23 February 2000     

A vascular sarcoid mass mimicking a convexity meningioma

We report a 48-year-old woman with a left posterior temporal extra-axial mass that had the imaging characteristics of a meningioma on preoperative CT, MRI and angiography. However, a biopsy diagnosis of sarcoidosis was made. This case illustrates that dural-based sarcoid masses can be very vascular and radiographically indistinguishable from meningiomas. Characteristic imaging features of extra- and intra-axial sarcoid lesions are discussed. Received: 4 March 1999/Accepted: 11 June 1999     

MRI evaluation of soft tissue hydatid disease

Infestation in soft tissue by Echinococcus granulosus is not a common disease, and its diagnosis is based on clinical, laboratory data and radiological findings. The aim of our retrospective study is to give an overview of the different signs and patterns shown by MRI that can be useful in characterizing soft tissue hydatid disease. The MRI images obtained in seven patients with soft tissue and subcutaneous hydatidosis were reviewed. Typical signs of hydatidosis were multivesicular lesions with or without hypointense peripheral ring (“rim sign”). Related to the presence and absence, respectively, of viable scolices in the microscopic exam, daughter cysts were presented either as high signal intensity or low signal intensity on T2-weighted images. Low-intensity detached layers within the cyst and peripheral enhancement with gadolinium-DTPA were also presented. Atypical signs were presented in an infected muscular cyst, a subcutaneous unilocular cyst and several unilocular cysts. Knowledge of the different patterns in MRI of soft tissue hydatid disease can be useful in diagnosing this entity. We observed that the “rim sign” is not as common as in other locations, and in addition, MRI seems to be of assistance when evaluating the vitality of the cysts. Received: 27 July 1998; Revision received: 11 March 1999; Accepted: 23 April 1999     

CNS sarcoidosis: evaluation with contrast-enhanced MR imaging.

Reports of findings on unenhanced MR images and contrast-enhanced CT scans in patients with intracranial sarcoidosis have suggested that MR imaging without contrast enhancement may miss meningeal involvement, which is a frequent and prominent finding in neurosarcoidosis. We studied 14 patients with CNS sarcoidosis with T1- and T2-weighted pre- and postcontrast sequences and T1-weighted postcontrast sequences. Eight of 12 patients with intracranial sarcoidosis and one of two with spinal sarcoidosis had meningeal involvement that was not apparent on the unenhanced scans. Eight of 12 patients had intraaxial areas of high signal intensity on T2-weighted images, although only two of these lesions enhanced. Three patients had enhancing extraaxial masses mimicking meningiomas on postcontrast T1-weighted images. In two patients, the lesions decreased markedly in size after steroid treatment. In one patient with sarcoidosis of the optic nerve, the lesion decreased in size and the patient's vision returned to normal after Cytoxan therapy. In five of 14 patients, CNS findings were the initial clinical manifestation of the disease. In nine of 14 patients, the diagnosis of neurosarcoidosis was suggested only after administration of contrast agent. Use of gadopentetate dimeglumine greatly enhances the sensitivity of MR imaging in the detection of CNS sarcoidosis.     

CT of radiatioe-indeced injury of the gastrointestinal tract spectrum of findings with barium studies correlation

Because of improvement in survival rate of patients with abdominal cancer, gastrointestinal complications following external radiation therapy are becoming more frequent. Thus, an increased number of patients are commonly investigated with imaging because of suspected radiation-induced injury of the gastrointestinal tract. This pictorial review highlights the spectrum of CT and barium study manifestations of radiation-induced injury of the gastrointestinal tract. The major role of CT in the evaluation and management of patients with radiation injury of the gastrointestinal tract is highlighted. Emphasis is placed on CT imaging signs that may help in distinguishing between radiation-induced injury and recurrent disease. Received: 19 October 1999; Accepted: 15 November 1999     

CT and MR findings in neoplastic perineural spread along the vidian nerve

The aims of this article are to describe the findings of perividian tumor spread and to compare the accuracy of MRI and CT in diagnosing perineural metastasis along the vidian nerve. Moreover, the frequency of perividian metastasis in patients with head and neck cancer was evaluated. The CT and MR examinations of 98 consecutive untreated patients with histologically proven head and neck cancer were retrospectively reviewed. We considered as criteria for perineural tumor spread along the vidian nerve the following CT and MR findings: For CT (a) enlargement of the pterygoid canal, (b) erosion of its bony wall, and (c) obliteration of its normal fatty content; and for MR (a) enlargement of the vidian nerve, (b) enhancement of the nerve, and (c) obliteration of fat, particularly in the anterior part of the pterygoid canal. Ten patients met the selected criteria for perineural metastasis, which was bilateral in 3 patients, with a total of 13 vidian metastases. The CT scans demonstrated unilateral involvement of the vidian nerve in 9 patients. The MRI scans showed 13 perineural metastases. In 3 patients MR scans demonstrated involvement of four vidian nerves that appeared normal on CT examinations. The diagnostic difference between CT and MRI was statistically significant (Fisher's exact test; p = 0.04). Perineural spread along the vidian nerve is an event more frequent than previously reported and must be investigated with a careful imaging technique. Although a major limitation of our study is the lack of histological proof, the MR finding of a significant enhancement of the nerve, whether enlarged or normal in size, could be considered very suggestive of this kind of metastatic spreading, particularly if associated with simultaneous involvement of the neighboring structures (pterygopalatine fossa, foramen lacerum, trigeminal branches, etc.). Received: 5 January 1999; Revision received 11 May 1999; Accepted: 17 June 1999     

Percutaneous treatment with amphotericin B of mycotic lung lesions from invasive aspergillosis: results in 10 immunocompromised patients

The aim of this study was to evaluate the efficacy of percutaneous treatment of pulmonary lesions from invasive aspergillosis in immunocompromised patients. From 1992 to 1998, ten patients (seven men and three women; mean age 56 years) affected by hematological neoplasms (8 acute myeloid leukemias, 2 non-Hodgkin's lymphomas) and post-chemotherapy prolonged neutropenia developed pulmonary lesions from invasive aspergillosis. A total of 13 lesions (diameter 2–7 cm, median 5 cm) were treated percutaneously due to insufficiency of the high-dose i. v. therapy; under CT guidance, a median of 10 cm³ per session of a 1 mg/cm³ diluted solution of amphotericin B was injected through a fine needle (21–22 G); 45 sessions overall were performed (one to five per lesion, median four), according to the volume of the nodules, tolerance, and complications. The results were retrospectively evaluated either radiologically or clinically. Complications were cough, mild hemoptysis, and small pneumothorax and/or pleural effusion. No major complications occurred. One month after the beginning of treatment, 8 lesions completely resolved, 4 greatly improved, and 1 was not significantly reduced. In all ten patients symptoms improved (eight of ten could restart chemotherapy as scheduled). After antiblastic retreatment, 1 patient had mycotic recurrence. In our experience transthoracic topical treatment with amphotericin B of single or few lung lesions from invasive aspergillosis was effective, affording a rapid improvement of the lesions and symptoms, and allowing continuation of chemotherapy as scheduled, thereby reducing the risk of recurrences. Received: 16 November 1999; Revised: 5 April 2000; Accepted: 6 April 2000     

Cerebrospinal fluid flow in patients with dilated ventricles studied with MR imaging

The purpose of this study was to measure the cerebrospinal fluid (CSF) velocity and flow in the aqueduct in patients with wide ventricles with or without signs of normal pressure hydrocephalus (NPH) before and after shunt surgery. We studied 18 patients with wide ventricles with MRI and measured the CSF velocity values in the aqueducts. Twelve patients with the clinical triad of NPH were examined. Six patients were studied only before shunt surgery and 6 patients were studied both before and after shunt surgery. Three patients with wide ventricles without clinical triad of NPH, and 3 patients with hydrocephalus following subarachnoid hemorrhage were also examined. Seven NPH patients with hyperdynamic CSF flow and three NPH patients with normal CSF velocity and flow values showed a positive clinical response to shunt surgery. Two of the three patients with hydrocephalus and hyperdynamic CSF flow values in the aqueduct secondary to subarachnoid bleeding responded to shunt surgery. One patient with same disease and low CSF velocity and flow values did not respond. No change was detected in the CSF flow values of the aqueduct when measurements before and after shunt surgery were compared. Ventriculoperitoneal shunting does not change the CSF dynamics in the aqueduct. Received: 8 March 1999; Revised: 30 November 1999; Accepted: 23 February 2000     

Role of the intra-arterial calcium stimulation test in the preoperative localization of insulinomas

The aim of this study was determination of the significance of the arterial stimulation test with venous sampling (ASVS) in the preoperative localization of insulinoma. Eleven patients with endogenous hyperinsulinism underwent preoperative transabdominal US, spiral computer tomography (spiral CT), MRI, endoscopic ultrasound (EUS) as well as angiography (DSA) combined with ASVS. The results were compared with intraoperative findings, intraoperative ultrasound (IOUS) and histopathology. There were no complications related to the ASVS test. In 11 patients the tumor could be localized with the various modalities as follows: US 1 of 11 (9 %), MRI 3 of 10 (30 %), spiral CT 4 of 11 (36 %), EUS 5 of 10 (50 %), DSA 8 of 11 (73 %), and ASVS 10 of 11 (91 %). In 2 patients the tumors were intraoperatively neither palpable nor detectable by IOUS, and consequently the intraoperative management was governed by information provided by DSA combined with the ASVS test. Ten patients had solitary benign insulinomas and 1 patient with multiple endocrine neoplasia I had two tumors adjacent to each other in the pancreatic tail. Arterial stimulation test with venous sampling was the most sensitive preoperative test for regionalizing the insulinoma in our set of patients. It can be performed safely in the course of a regular DSA examination and may affect intra-operative management in patients in whom the tumors are not detectable by palpation or IOUS. Received: 23 June 1999; Revised: 13 January 2000; Accepted: 29 February 2000