Gaucher disease: assessment with MR imaging

The skeletal system, spleen, and liver of five patients with proved Gaucher disease were studied with magnetic resonance (MR) imaging. Homogeneous, low intensity signals resulting from relaxation times different than normal (longer T1 and shorter T2 values) were found in the marrow of long bones, vertebrae, and hips in all patients. In three patients, normal signals were noted in the patella, epiphysis of the knee, and capital femoral epiphysis. In two patients with acute bone pain in the tibial region, a higher signal was received from the tibial marrow. This signal was related to increased accumulation of fluid following an avascular episode. Soft tissues in the same area were also involved. Liver and spleen enlargement was readily visible, especially on coronal images. T1 values of spleen were significantly shorter than normal. MR imaging provides an excellent assessment of the extent of involvement of the liver, spleen, and bone marrow in Gaucher disease.     

Spectrum of abdominal sonographic findings in 103 pediatric patients with Gaucher disease

The purpose of this study was to catalogue spleen and liver features by US in a cohort of 103 pediatric patients with Gaucher disease, and to document response to enzyme replacement therapy by serial US examination. There were 42 boys and 61 girls, 2 were splenectomized. Forty-eight patients received enzyme replacement therapy (ERT). At presentation all patients evinced organomegaly and 4.9% had focal (splenic or hepatic) lesions (hypo- and hyper-echoic or mixed). Fifteen patients began ERT before 11 years of age. There was a mean liver volume reduction from 230 to 137% after 2 years of ERT, with further reduction of 91% up to 6 years later. Mean spleen volume reduction was 38.4% at 2 years of ERT and a further reduction to 40.8% at last evaluation. Fourteen children began ERT between ages 11 and 16 years. Mean liver reduction was from 230 to 124% at 2 years and further reduction to mean of 104% recently. Mean splenic reduction was 37.7% after 2 years of ERT, with a mean of 43.8% recently (mean 4.5 years later). Organ volume changes in untreated and treated children were documented by US which is the modality of choice for repeat measures in this population. Our results highlight the initial dramatic and then continued response to ERT in pediatric patients with Gaucher disease.     

Paget disease: MR imaging findings

Magnetic resonance (MR) images of 13 patients with Paget disease were reviewed, and findings were correlated with those from computed tomographic (CT) scans, radiographs, and, in two patients, surgical biopsy. MR imaging findings correlated with CT and radiographic findings of cortical thickening, increased size of bone, and coarse thickened trabeculae. Focal or diffuse decreased signal intensity, representing dense bone, was seen on images obtained with short and long repetition times (TRs) and echo times (TEs); high-signal foci, representing fat collections, were seen on short TR/TE images; and high-signal foci, representing fibrovascular marrow in active Paget disease, were seen on long TR/TE images. Complications of Paget disease-including basilar invagination, spinal stenosis, and sarcoma--were well identified on MR images. Although MR imaging is not generally used in diagnosis of Paget disease, the disease will be encountered more frequently as more MR imaging examinations are performed. An awareness of the range of findings in Paget disease is useful in evaluating MR images of the musculoskeletal and other systems.     

Crohn's disease lymphadenopathy: MR imaging findings

Purpose

To assess mesenteric lymph nodes in patients with different Crohn's disease subtypes identified on MR Enteroclysis.

Materials and methods

Thirty-four patients, categorized into three different Crohn's disease subgroups, underwent MR Enteroclysis. A high resolution coronal true FISP sequence with fat saturation was applied to assess mesenteric lymph node anatomic distribution, size and shape. Their enhancement ratio (ER) was calculated by dividing signal intensity of each node to signal intensity of nearby vessel on T1 weighted FLASH images, acquired 75 s after intravenous administration of gadolinium. A one-way analysis of variance statistical test was applied to investigate any significant differences regarding mean ER among different disease subgroups.

Results

Two hundred and eighty-three mesenteric lymph nodes were assessed, 231 in patients with active inflammatory (AI) disease, 36 in patients with fibrostenotic (FS) and 16 in patients with fistulizing/perforating (FP) disease. Maximum and minimum diameters were 3.2 and 0.3 cm, respectively. 75% of the lymph nodes presented with an oval shape. The majority were identified as being ileocolic (34%) and paracolic (31%). AI subgroup lymph nodes presented with the highest mean ER (0.783 ± 0.17) followed by FP (0.706 ± 0.1) and FS subgroup (0.652 ± 0.17) lymph nodes. The differences in mean values of ER of mesenteric lymph nodes between AI and FS subtypes were statistically significant (p < 0.0001), while mean ER between nodes of FP and the other two subtypes did not present statistically significant differences.

Conclusion

ER of mesenteric lymph nodes identified on MR Enteroclysis may vary across different subtypes of Crohn's disease. Such differences may be valuable in clinical practice.     

Peyronie's disease: MR findings in 28 patients.

Induratio penis plastica (Peyronie's disease) is a chronic fibrotic process involving the penis. Proper treatment of the disease requires assessment of the degree of inflammation preceding or accompanying the fibrous Peyronie's plaques. Owing to its high tissue contrast and its multiplanar capability, MR imaging offers excellent visualization of penile anatomy. To determine the usefulness of MR imaging in the diagnosis and staging of Peyronie's disease, we used MR imaging with a surface coil to examine 28 consecutive patients with clinical evidence of the disease. Eighteen patients had contrast-enhanced MR imaging with gadopentetate dimeglumine. In seven patients who subsequently had surgery or biopsy, MR findings were correlated with histopathologic findings. On unenhanced images, fibrous plaques were shown in 20 patients. Enhanced MR images showed focal contrast enhancement around or within the plaques in seven patients. Images in three patients with plaques showed no enhancement. Images in five patients showed focal areas of contrast enhancement without evidence of plaques. Histologic studies demonstrated that the degree of contrast enhancement correlated with the extent of inflammatory cell infiltration. In two patients with unenhancing plaques on MR, histology confirmed the absence of inflammation. Our results suggest that MR imaging not only depicts the localization and extent of fibrous plaques in patients with Peyronie's disease but also reveals the presence of inflammation. This makes MR imaging the technique of choice for planning therapy and for evaluating the response to conservative treatment.     

Intraocular lesions in patients with systemic disease: findings on MR imaging

Twenty-one intraocular lesions associated with various systemic diseases in 15 patients were studied by MR imaging. The disorders included diabetes mellitus, cardiovascular disease, Beh?et disease, sarcoidosis, and ankylosing spondylitis. MR was performed on a 0.5-T system using a surface-coil technique. Ophthalmoscopic visualization of the fundus was precluded by the presence of opaque media in all cases. MR was found to be effective in demonstrating intraocular bleeding, vitreous opacity, detached lesions of the posterior pole, and eyeball deformity. Surface-coil MR is a useful adjunct in the evaluation of the eyes affected by systemic diseases, especially in patients with opaque media.     

Intraocular lesions in patients with systemic disease: findings on MR imaging

Twenty-one intraocular lesions associated with various systemic diseases in 15 patients were studied by MR imaging. The disorders included diabetes mellitus, cardiovascular disease, Beh?et disease, sarcoidosis, and ankylosing spondylitis. MR was performed on a 0.5-T system using a surface-coil technique. Ophthalmoscopic visualization of the fundus was precluded by the presence of opaque media in all cases. MR was found to be effective in demonstrating intraocular bleeding, vitreous opacity, detached lesions of the posterior pole, and eyeball deformity. Surface-coil MR is a useful adjunct in the evaluation of the eyes affected by systemic diseases, especially in patients with opaque media.     

Kimura disease: CT and MR imaging findings

BACKGROUND AND PURPOSE:KD is a rare chronic inflammatory disorder of unknown etiology. The purpose of this study was to evaluate the CT and MR imaging findings of KD in the head and neck.MATERIALS AND METHODS:We retrospectively reviewed the CT (n = 21) and MR (n = 9) images obtained in 28 patients (24 males and 4 females; mean age, 32 years; age range, 10–62 years) with histologically proved KD in the head and neck.RESULTS:In these 28 patients, CT and MR images demonstrated a total of 52 non-nodal lesions, 1–8 cm in greatest diameter, in the head and neck. The lesions were unilateral in 11 patients and bilateral in 17 patients. Eleven patients had a solitary lesion, and 17 patients had 2–4 lesions. The parotid and/or periparotid area was the most frequent location, with 36 lesions in 23 patients. The margin of the lesions was well-defined in 1 and ill-defined in 51 cases. Compared with the adjacent muscle, the MR signal intensity of all lesions was iso- to slightly hyperintense on T1-weighted images and hyperintense on T2-weighted images. Most of the lesions demonstrated mild or moderate enhancement on postcontrast CT scans and moderate or marked enhancement on postcontrast MR images. MR images also showed tubular signal-intensity voids in 7 of 13 lesions. Associated lymphadenopathy was demonstrated in 23 patients, usually bilaterally.CONCLUSIONS:Multiple ill-defined enhancing masses within and around the parotid gland with associated regional lymphadenopathy are characteristic CT and MR imaging findings of KD in the head and neck.

KD is a rare chronic inflammatory disorder of unknown etiology, characterized by angiolymphoid proliferation with peripheral eosinophilia and elevated serum IgE. The disease has a predilection for the head and neck and typically occurs in young Asian males.^1,2 Although it was first described in the Chinese literature in 1937 under the designation of “eosinophilic hyperplastic lymphogranuloma,” it was not until 1948 that the disease to become widely known as KD when Kimura and Ishikawa³ reported it in the Japanese literature.⁴ KD often produces subcutaneous tumorlike nodules with frequently associated involvement of the major salivary gland and regional lymph nodes.⁵Although the clinical and histopathologic findings of KD have been well described in the literature, only a few reports have dealt with its radiologic findings, and generally as case reports or small case series.^6–15 The purpose of this study was to describe the CT and MR imaging findings of histologically proved KD involving the head and neck in 28 patients. To our knowledge, this is the largest imaging study of patients with KD of the head and neck.     

Radiation myelopathy in over-irradiated patients: MR imaging findings

The objective of this work is to report the MRI findings in patients with radiation myelopathy due to accidental local over-irradiation syndrome. Eight patients (seven males and one female) were suffering from over-irradiation syndrome as a result of treatments from a malfunctioning linear electron accelerator. The mean accidental estimated dose was 136 Gy delivered to the “open-neck” (seven cases) and to the thoracic wall (one case), during a mean of 5.4 sessions (range 1–9 sessions). Paresthesia and weakness in the upper extremities were the earliest symptoms (87.5 %), with evolution to paralysis in all patients. No patient is alive (mean survival time 64 days). In all cases MRI was negative for neurologic lesions in the acute phase ( < 90 days from irradiation; Radiation Therapy Oncology Group scoring system). Late signs of radiation myelitis manifested as high-intensity signals on T2-weighted images in three patients, and as Gd-DTPA enhancement of T1-weighted images in one case. Autopsies performed on four patients who died in acute phase showed morphologic alterations in white matter: edema in 75 %, and necrosis and glial reaction as well as obliterative vasculitis in all cases. In cases of over-irradiation, MRI may be normal in acute phase even if the patients have severe neurologic deficit, as positive MRI findings appear only in delayed radiation myelitis. Received 25 March 1996; Revision received 3 July 1996; Accepted 4 September 1996     

Painful heel: MR imaging findings.

Heel pain is a common and frequently disabling clinical complaint that may be caused by a broad spectrum of osseous or soft-tissue disorders. These disorders are classified on the basis of anatomic origin and predominant location of heel pain to foster a better understanding of this complaint. The disorders include plantar fascial lesions (fasciitis, rupture, fibromatosis, xanthoma), tendinous lesions (tendinitis, tenosynovitis), osseous lesions (fractures, bone bruises, osteomyelitis, tumors), bursal lesions (retrocalcaneal bursitis, retroachilleal bursitis), tarsal tunnel syndrome, and heel plantar fat pad abnormalities. With its superior soft-tissue contrast resolution and multiplanar capability, magnetic resonance (MR) imaging can help determine the cause of heel pain and help assess the extent and severity of the disease in ambiguous or clinically equivocal cases. Careful analysis of MR imaging findings and correlation of these findings with patient history and findings at physical examination can suggest a specific diagnosis in most cases. The majority of patients with heel pain can be successfully treated conservatively, but in cases requiring surgery (eg, plantar fascia rupture in competitive athletes, deeply infiltrating plantar fibromatosis, masses causing tarsal tunnel syndrome), MR imaging is especially useful in planning surgical treatment by showing the exact location and extent of the lesion.     

White matter disease in AIDS: findings at MR imaging

A review of the magnetic resonance (MR) images of 365 patients with acquired immunodeficiency syndrome (AIDS) revealed that 112 (31%) had signal abnormalities confined to the white matter. Four patterns were observed: (a) diffuse: widespread involvement of a large area; (b) patchy: localized involvement with ill-defined margins; (c) focal: well-defined areas of involvement; and (d) punctate: small foci less than 1 cm in diameter. Clinical or pathologic findings were available in 60 of the 112 patients and were correlated with the white matter patterns seen on MR images. The diffuse pattern correlated with AIDS dementia complex (ADC), which was the most common clinical diagnosis. Patchy or punctate lesions may be seen with ADC but are less common. Focal white matter lesions were not seen in patients with ADC but were seen in all six patients with progressive multifocal leukoencephalopathy, in both patients with lymphoma, and in one patient with toxoplasmosis. The authors conclude that white matter lesions are are common in AIDS and are often secondary to direct infection of the brain with human immunodeficiency virus, which causes the ADC and usually produces a diffuse white matter pattern. Biopsy is probably not indicated in these patients. Focal white matter lesions suggest a focal infection or tumor, and biopsy may be warranted.     

Perianal complications of Crohn disease: MR imaging findings

The aim of this study was to revisit anal anatomy, to explain surgical terminology in perianal complications of Crohn disease, and to show the MR imaging findings of perianal fistulas and abscesses. To this end more than 200 patients were studied using surface coils (Helmholtz; phased array) at 1.0 and 1.5 T. Transverse and coronal T1- and T2-weighted images were obtained. Parks' classification was used to describe perianal abscesses and fistulas. This pictorial essay shows the normal anal anatomy and pathologic findings such as subcutaneous, para-anal, ischiorectal, intersphincteric, and supralevatoric abscesses and fistulas. MR imaging with surface coils is well suited to showing the anal anatomy and to reliably describing perianal abscesses and fistulas according to surgical terminology. Received: 7 October 1996; Revision received 4 December 1996; Accepted 10 December 1996     

Quantitative imaging of Gaucher disease.

Twenty-three patients with type 1 Gaucher disease were evaluated with a battery of quantitative imaging techniques. Plain radiographs were used to measure cortical thickness and Erlenmeyer flask deformity. Xenon-133 uptake was measured in scans of the lower extremities. Dual-energy quantitative computed tomography was used for calculation of trabecular bone and bone marrow fat content in the spine and long bones. Magnetic resonance (MR) imaging was performed to evaluate disease extent and three-dimensional splenic volume. MR images were also used to provide quantitative measurements of each vertebral fat fraction. Each imaging modality was correlated with the others as well as with the clinical history of skeletal complications and the hematocrit and acid phosphatase activity. There was a strong relationship between splenic volume and disease severity as measured clinically and with laboratory testing. The spinal fat fraction also correlated with these measures of disease severity and with the femoral fat fraction and xenon uptake. No measurement allowed discrimination of patients with from those without skeletal complications.     

Ovarian carcinoma in patients with endometriosis: MR imaging findings

OBJECTIVE: Various types of malignancy can develop in patients with endometriosis. Enhancing mural nodules have been reported as an imaging characteristic of malignant transformations. We evaluated contrast-enhanced MR imaging to determine the optimum sequence to reveal mural nodules and other characteristics of malignant transformations. MATERIALS AND METHODS: We examined 10 patients with pathologically proven ovarian adenocarcinoma in endometriosis and 10 patients (the control group) with ovarian endometrioma suggestive of malignant transformation on the basis of sonographic findings. We analyzed the size and nature of the endometriomas in each patient. We compared four types of contrast-enhanced MR imaging to determine which sequence best revealed mural nodules. RESULTS: In the malignant and control groups, 80% of the cysts with findings suggestive of malignant transformation showed unilateral disease or larger endometrial cysts on the suggestive side than on the contralateral side. High signal intensity on T1-weighted images and low signal intensity on T2-weighted images relative to the myometrium were observed only in two of 10 malignant endometrial cysts and in all control cysts. All malignant endometriomas had small mural nodules with low signal intensity on T1-weighted contrast-enhanced images. Only three benign endometriomas had mural nodules and none of them enhanced. The enhancement of mural nodules was easily seen on dynamic subtraction imaging. CONCLUSION: On the basis of our findings, endometrial cysts with malignant transformation rarely show low signal intensity on T2-weighted images and usually have enhancing mural nodules. Because the enhancement of mural nodules is often difficult to evaluate on conventional T1-weighted images, dynamic subtraction imaging can be valuable.     

Sacroiliitis: MR imaging findings

Magnetic resonance (MR) imaging was performed in seven asymptomatic volunteers and 17 patients with clinical and radiologic evidence of sacroiliitis. MR imaging findings were compared with those at computed tomography (CT) to determine the MR imaging appearance of the sacroiliac joint when normal and in sacroiliitis. The normal articulation was well depicted with MR imaging. Findings of sacroiliitis were identified in 20 sacroiliac joints (12 patients). MR imaging findings characteristic of sacroiliitis included abnormal cartilage signal intensity (95% of joints) and erosions (75% of joints) on T1-weighted images. Areas of increased intensity in the articulation (80% of joints) or in erosions (60% of joints) were seen on T2-weighted images. MR imaging was superior to CT for evaluation of cartilage and detection of erosions. Four sacroiliac joints (20%) and two patients (17%) with MR imaging findings of sacroiliitis were negative at CT. The authors conclude that MR imaging is a valuable method for detecting sacroiliitis, particularly when results of other imaging techniques are inconclusive.     

Intradural-extramedullary spinal cysticercosis: MR imaging findings.

A rare case with intradural-extramedullary cysticercosis is presented here. MR imaging with and without gd-DTPA were performed. There were multiple cysts in the basal cistern, cisterna magna, and cervical subarachnoid space which were isointense with cerebrospinal fluid both on T2- and T1-weighted images. Swelling and increased signal intensity in the cord parenchyma were detected on T2-weighted images. Gadolinium enhanced studies showed rim-shaped enhancement in the cysts and irregular, diffuse enhancement in the meninges.     

MR imaging findings in patients with bone-chip allografts

Increasing use of MR to evaluate primary bone neoplasms has stimulated numerous articles on the initial assessment of these lesions. However, scant MR literature has been written about the postoperative MR appearance. We studied the MR appearance of lesions treated by curettage followed by packing with cancellous bone-chip allograft. We retrospectively reviewed the MR scans of 18 consecutive patients treated in this way. Pathologic diagnoses of these lesions were confirmed according to commonly accepted criteria. The allograft sites showed a distinctive pattern of speckled bright signal on T1-weighted images in eight cases. Thirteen of 18 grafts showed a whorled or speckled pattern of increased signal on the T2-weighted images. Only four allograft regions had predominantly low signal on both T1- and T2-weighted images. Two of 18 patients had recurrent tumor proved by open biopsy. MR images in these cases showed areas of homogeneous signal that replaced areas of speckled hyperintensity on both T1- and T2-weighted images. In both these recurrences the tumor had signal intensity similar to that seen on the preoperative MR study. We conclude that knowledge of the MR appearance of cancellous bone chip allografts is important to avoid misinterpreting areas of high signal on T1- or T2-weighted images as areas of recurrence of tumor and/or hemorrhage.     

Acute Marchiafava-Bignami disease: MR findings in two patients

Marchiafava-Bignami is a rare toxic disease seen mostly in chronic alcoholics that results in progressive demyelination and necrosis of the corpus callosum. The process may extend laterally into the neighboring white matter and occasionally as far as the subcortical regions. We present the MR imaging findings in two patients who presented acutely and review the features of the disease and of other acute alcohol-related disorders.