Destruction Of Adjacent Bone Research Articles

Adenoid cystic carcinoma of head and neck: Summary and review of imaging findings

PurposeCurrent reports of adenoid cystic carcinoma of the head and neck (ACC) are all case reports, and there is no basilar summary of its imaging findings. This study aims to summarise ACC's computed tomography (CT) and magnetic resonance imaging (MRI) findings to improve radiologists' knowledge of this disease. MethodsWe collected clinical and imaging data of patients with ACC during the last decade, and two radiologists retrospectively analysed the imaging characteristics. ResultsOf the 16 patients included, six were able to self-perceive bulkiness, and 11 had regional pain. Tumour morphology was regular in six cases, with clear borders in 11 cases, invasion of the surrounding bony mass in 12 cases, and invasion of peripheral nerves in 15 cases. CT mostly shows an irregular soft-tissue density mass with mild-to-moderate enhancement after contrast medium administration. On MRI, the ACC showed isointense or hypointense signals on T1-weighted images (T1WI) and hyperintense or slightly hyperintense signals on T2-weighted images (T2WI). All signals were markedly enhanced after gadolinium enhancement. ConclusionsACC often has an irregular morphology, sometimes with a cystic component, enhancement on enhancement scans, easy destruction of adjacent bone, and invasion of peripheral nerves. The diagnosis should be considered when these features are encountered in clinical practice.

Microdrilling Resulted in Less Subchondral Bone Destruction Than a Traditional Microfracture Awl for Articular Cartilage Defect Bone Marrow Stimulation

The purpose of this study was to compare bone marrow stimulation using micro-computed tomography (micro-CT) analysis of an abrasion arthroplasty technique, drilling k-wire technique, traditional microfacture awl, or a microdrill instrument for subchondral bone defects. Eleven cadaveric distal femoral specimens were obtained and divided into 3 common areas of osteochondral defect: trochlea and weightbearing portions of the medial and lateral femoral condyles. Each area of interest was then denuded of cartilage using a PoweRasp and divided into quadrants. Each quadrant was assigned either a 1.6 mm Kirschner wire (k-wire), 1.25 mm microfracture awl, 1.5 mm fluted microdrill, PowerPick, or a curette (abrasion arthroplasty) to create 4 channels into the subchondral bone sing the same instrument. Subchondral bone and adjacent tissue areas were then evaluated using micro-CT to analyze adjacent bone destruction and extension into the bone marrow. Overall, there was a significantly decreased area of bone destruction or compression using the microdrill (0.030 mm) as compared to the microfracture awl (0.072 mm) and k-wire (0.062 mm) (P < .05). Within the trochlea and the medial femoral condyle, there was significantly decreased bony compression with the microdrill as compared to the awl and k-wire (P < .05); however, when stratified, this was not significant among the lateral femoral condylar samples (P= .08). Bone marrow stimulation causes bony compression that may negatively impact subchondral bone and trabecular alignment. It is important to understand which tools used for bone marrow stimulation cause the least amount of damage to the subchondral bone. This study demonstrates the decreased subchondral bony defects seen with the microdrill versus the traditional microfracture awl indicating that when performing bone marrow stimulation, the microdrill may be a less harmful tool to the subchondral bone.

A Novel Surgical Classification for Extremity and Pelvic Hemophilic Pseudotumors: The PUMCH Classification.

A hemophilic pseudotumor (HPT) is a rare and challenging complication of hemophilia for which there is no classification system that provides uniformity of descriptions or that can be used to guide management. We have developed such a classification based on anatomical site, HPT severity, and corresponding surgical treatment. The PUMCH (Peking Union Medical College Hospital) classification was developed on the basis of clinical manifestations and imaging features. Extremity and pelvic HPTs were divided into 4 types and 6 subtypes according to anatomical site and whether or not there was destruction of adjacent bone. Associations between the PUMCH classification and surgical treatment, preoperative comorbidities, operative time, intraoperative bleeding, and postoperative complication rates were analyzed. Forty-five patients with 53 HPTs that were treated at PUMCH between December 2005 and October 2021 were included. The mean age at the time of surgery was 35.4 ± 11.9 years, and the median follow-up duration was 60.3 months. Twenty-eight HPTs were classified as type I (13 IA, 7 IB, 8 IC); 3, as type II; 6, as type III; and 16, as type IV. All 20 type-IA and IB HPTs were treated with excision, and the 3 type-II HPTs were treated with curettage and bone grafting. Fourteen type-IV pelvic HPTs underwent excision, 2 of which needed concomitant pelvic reconstruction. Six type-IC HPTs and 1 type-III HPT underwent excision and osseous reconstruction. Amputation was required for 1 type-IC and 3 type-III HPTs. Type-IC HPTs had the longest mean operative time (194.3 ± 28.2 minutes) and the greatest intraoperative bleeding (2,000 mL [interquartile range, 1,100 to 3,000 mL]). Postoperative infection was more common in patients with type-III (50.0%) and type-IC (28.6%) HPTs, but not significantly so. The PUMCH classification is based on the anatomic pathology and surgical strategy for HPTs. The classification of HPTs corresponds to surgical outcomes, and may be helpful for decision-making regarding their surgical treatment. Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Primary leiomyosarcoma of the spine: an analysis of imaging manifestations and clinicopathological findings

BackgroundPrimary leiomyosarcoma of the spine is extremely rare and lacks specific clinical symptoms. This study investigated the imaging manifestations and clinicopathological findings of primary leiomyosarcoma of the spine, aiming to improve the radiologists’ understanding of the disease and reduce misdiagnoses.MethodsThe clinical, imaging, and pathological manifestations in eleven patients with pathologically confirmed primary leiomyosarcoma of the spine were retrospectively analyzed. The imaging features analyzed included lesion location, shape, border, size, and density/intensity, and adjacent bone destruction status, residual bone trabeculae, vertebral compression, and contrast enhancement.ResultsThe patients’ primary clinical symptom was usually focal pain. Primary leiomyosarcoma of the spine was mostly a solitary lesion and tended to occur in the posterior elements. The tumors had a lobulated shape with osteolytic bone destruction, ill-defined borders, and could involve multiple segments. Computed tomography (CT) examination showed isodense masses. Six patients showed residual bone trabeculae. Two patients had miscellany T2-weighted imaging (T2WI) signals, while the tumor and spinal cord of the remaining patients were isointense on T1-weighted imaging (T1WI) and T2WI. Among the seven patients who underwent contrast-enhanced scanning, six displayed homogeneous enhancement. Eight patients underwent gross-total tumor resection with no recurrence.ConclusionsPrimary leiomyosarcoma of the spine tends to be a solitary lesion in the posterior elements and appears as a lobulated mass with osteolytic bone destruction and an ill-defined border. The tumor and spinal cord can be isointense on T1WI and T2WI. Contrast-enhanced scanning displays homogeneous enhancement. The lesion tends not to recur after surgical gross-total tumor resection.

A Rare Presentation of Thoracic Intramedullary Chordoma with Adjacent Bone Involvement: A Case Report and Review of the Literature

Abstract Introduction/Objective Chordoma originates from remnants of the embryonal notochord, and arise in bones anywhere along the spine and skull base. The most common location was thought to be the sacrum, followed by the clivus, and to a much lesser extent the rest of the spine. However, some studies have suggested an equal distribution among the skull base (32%), mobile spine (32.8%), and sacro-coccygeal bones (29.2%). Here we report a case of chordoma involving the thoracic spine. at the level of T2. Methods/Case Report A 63-year-old male with no significant past medical history who presented with 5-6 months of intermittent, bilateral lower extremity weakness and numbness in the trunk and lower extremities. MRI of the thoracic spine demonstrated a contrast enhancing mass at T2 vertebral level with spinal cord compression and adjacent bone destruction. T1-3 laminectomy with debulking of the tumor was performed. Microscopically, the tumor cells have a lobulated architecture and are composed of epithelioid cells arranged in cords, clusters or nests, embedded in a myxoid mucinous matrix. The epithelioid cells have a variably vacuolated cytoplasm ("physaliphorous" cells). The epithelioid cells are positive for CK AE1/3, Cam5.2, EMA and Brachyury (nuclear stain), and S100 (focal). These findings support a diagnosis of chordoma. Results (if a Case Study enter NA) N/A. Conclusion The most important and difficult differential diagnosis of chordoma is with well-differentiated chondrosarcoma. Although both chordomas and chondrosarcomas express S100, chondrosarcomas do not express cytokeratins, EMA or brachyury. Chordomas have an aggressive clinical course and poor outcome with local extension, recurrence and even metastasis. The treatment is en block surgical resection with adjuvant radiotherapy. The extent of the initial surgical resection is the most significant prognostic factor.

Slow but disabling progression

Male, 84 years old, presented to the emergency room with obstipation associated with acute severe pain in the lumbar region. He had been living in the bed because he wasn´t able to do anything because the pain had been too disabling. Personal history of asthma, myocardial infarction, atrial fibrillation, dyslipidemia and obstipation. Physical examination was unremarkable, except for rectal examination which had a palpable posterior mass, without blood on the gloves. Complete body computer tomography with sacrococcygeal mass with 15 cm associated with bone destruction. Compression of the rectum, without invasion. Pelvic MRI: posterior mass with 12,3x15x8,6 cm with adjacent bone destruction without organ invasion. Histology of mass biopsy: sacrococcygeal chordoma. There was no indication for surgical treatment due to the major risks for the patient. Chordomas are rare, slow-growing, locally destructive bone tumours arising from the notochord. The most common locations are the clivus and the sacrococcygeal region. The annual incidence of these tumours is 1 in one million. MRI is the imaging modality of choice. Prognosis improves based on age, resected margins and postoperative treatment.

Differential Diagnosis of Sinonasal Extramedullary Plasmacytoma, Non-Hodgkin’s Lymphoma, and Squamous Cell Carcinoma Using CT Scan and MRI

Background: The imaging features of sinonasal extramedullary plasmacytoma (EMP) are non-specific and similar to those of other lesions, such as sinonasal non-Hodgkin’s lymphoma (NHL) and squamous cell carcinoma (SCC). Objectives: To analyze the computed tomography (CT) and magnetic resonance (MR) images of patients with EMP, NHL, and SCC to identify the radiological characteristics differentiating sinonasal EMP from NHL and SCC. Patients and Methods: In this cross-sectional study, the CT and MR imaging features of 37 patients with sinonasal EMP, 46 patients with NHL, and 44 patients with SCC were analyzed. Sinonasal NHL was categorized into two distinct types, namely, natural killer/T-cell lymphoma (n = 32) and diffuse large B-cell lymphoma (n = 14). The tumor volume was determined by measuring the region of interest (ROI) in the picture archiving and communication system (PACS) program. Besides, homogeneity, apparent diffusion coefficient (ADC) in the ADC maps, degree of enhancement, adjacent bone destruction, and invasion to Waldeyer’s ring and cervical or retropharyngeal lymph nodes were evaluated. Results: Although the tumor volume was larger in the EMP group as compared to the NHL and SCC groups, the difference was not statistically significant. The NHL group showed the highest tumor homogeneity on both CT and MR images. EMP was more heterogenous than NHL, with moderate signal intensity on T1-weighted MR images. On the other hand, EMP and NHL showed significantly lower ADCs as compared to SCC. The majority of patients with sinonasal EMP, NHL, and SCC showed an avid enhancement. Also, destructive tumor growth involving the adjacent bone was more frequent in SCC than in EMP or NHL. However, there were no significant differences among sinonasal EMP, NHL, and SCC in terms of invasion to Waldeyer’s ring and cervical or retropharyngeal lymph node metastasis. Conclusion: Marked heterogeneity on T1-weighted images, low ADCs, and lack of adjacent bone destruction were the CT and MR imaging features that favored the diagnosis of EMP over NHL or SCC.

Subclinical enthesopathy of extensor digitorum tendon is highly prevalent and associated with clinical and ultrasound alterations of the adjacent fingernails in patients with psoriatic disease.

Nail psoriasis disease is associated with an increased probability of psoriatic arthritis, and its clinical signs may have different correlates with the pathogenesis of adjacent bone destruction and have different prognostic value. Recent publications about psoriasis and nail psoriatic disease describe different ultrasonographic findings but the relationship between these ungueal alterations measured by ultrasonography and the presence of enthesopathy of the extensor digitorum has yet to be discovered. To describe which ultrasonographic characteristics of nail psoriasis are associated with the presence of subclinical enthesopathy in patients with PsO and asymptomatic PsA. Patients with psoriasis and asymptomatic psoriatic arthritis were included in the prospective study. Demographic, clinical data and PASI and NAPSI indexes were recorded of all the patients in the assessment visit. The US assessment included Achilles tendon, extensor digitorum tendon and US scan of the nail plate, nail matrix, nail bed and adjacent skin over nail matrix of the five nails of each hand. Forty-eight patients were included in the study; 33 of them presented ultrasound evidence of extensor digitorum tendon enthesopathy. Nails of the patients with subclinical enthesopathy had a higher NAPSI and skin thickness than the nails of the patients without subclinical enthesopathy (P = 0.047). Patients with asymptomatic enthesopathy had significantly thicker proximal nail folds (1.44 ± 0.312 vs. 1.23 ± 0.27, P = 0.023). Nail beds and matrices were also thicker but the differences were not statistically significant (1.77 ± 0.27 vs. 1.74 ± 0.21, P = 0.66, and 1.79 ± 0.28 vs. 1.67 ± 0.19, P = 0.10, respectively). No statistically significant differences in the trilaminar structure were found between both groups. Patients with and without asymptomatic enthesopathy of extensor digitorum tendons did not statistically differ as regards ultrasonographic alterations of the Achilles tendons (60.6% vs. 46.4%, P 0.368). Enthesopathy abnormalities can be detected by US in patients with psoriasis without musculoskeletal complaints frequently. There is a close relationship between subclinical enthesopathy of the extensor digitorum tendon and the presence of nail alterations. Further studies are required to research what implications have the presence of these ungual alterations measured by US, and how it affects later development of a PsA.

Invasive basal cell carcinoma: A case report

Basal cell carcinoma (BCC) is an epithelial tumor of low-grade malignancy, recurrent, with capacity for local invasion and destruction of adjacent bone or cartilage, yet rare metastasis. It presents as superficial, fibro-epithelial, nodular, sclerosing or pigmented. The best treatment is surgical excision; and frequently the cancer has a good prognosis. The purpose of this article is to study and discuss the clinical, histopathological and treatment of BCC.Descriptors: Maxillofacial Abnormalities; Neoplasms; Carcinoma, Basal Cell; Diagnosis; Therapeutics.

MULTIPLE MALIGNANT TUMORS IN 8-YEARS OLD BOY WITH XERODERMA PIGMENTOSUM: A CASE REPORT

This case report describes xeroderma pigmentosum in an 8-year old boy. At the age of 4 he was diagnosed with aggressive keratinizing squamous cell carcinoma. Surgical treatment, close-focus radiotherapy, isotretinoin and cyclosporine were ineffective. At the age of 8 he had multiple tumors on the face and concha of the ear, with destruction of adjacent bone and cartilage and regional nodal metastasing.

Orbital multilobular osteochondrosarcoma in a dog

Retrobulbar tumors may arise from any orbital tissue. Some are primary and others may extend from adjacent structures or derived from metastases. Multilobular osteochondrosarcomas are regarded as slowly growing and potentially malignant neoplasms in dogs. This tumor is of rare occurrence on retrobulbar region. This paper aims to report a rare case of female dog, Shih Tzu, spayed, five-year-old, that was referred to the Hospital of Veterinary Medicine, Federal University of Bahia, Brazil, with an increased volume in the orbital space, after enucleation for exophthalmia of unknown etiology. This animal was evaluated clinic and the diagnosis image (radiography and computed tomography) demonstrated a large formation of bone predominantly in the region of the right orbit and zygomatic arch, with invasion and destruction of adjacent bones. Due to her poor quality of life, the dog was submitted to euthanasia and after necropsy. On gross examination, an encapsulated nodular mass with an irregular surface, measuring 5.6 x 4.6 x 3.9 cm, was located in the right lateral skull, occupying the orbit with displacement of the zygomatic arch. The tumor was identified by histopathology as a malignant mesenchymal neoplasm, multilobular osteochondrosarcoma. Thus, differential diagnoses for exophthalmos should include cancers, including the multilobular osteocondrossarcoma.

Adenoid cystic carcinoma of the maxillary sinus: CT and MR imaging findings

The purpose of this study was to determine whether adenoid cystic carcinomas (ACCs) of the maxillary sinus have features on CT and MR imaging. Nine patients with histopathologically proved maxillary sinus ACCs were included. The growth pattern was classified as expansile or destructive types on the basis of CT images. CT images were also reviewed for adjacent bony defects and MR images were reviewed for tumor extension. Fluid accumulation in the ipsilateral maxillary sinus was also assessed. The tumors had caused adjacent bony expansion with minimal bony defects in 4 patients whereas those in the remaining 5 patients had caused extensive destruction of adjacent bones comprising the maxillary sinus walls. Nasal cavity invasion was observed in 7 patients, retroantral fat pad invasion in 5, pterygopalatine fossa invasion in 4, and orbital invasion in 3. All 4 expansile ACCs were accompanied by accumulation of a small amount of fluid in the surroundings of the tumors, which was revealed as hyperintensity on T1-weighted images. The growth pattern of maxillary sinus ACCs can be classified into an expansile type with minimal bony defects and a destructive type with extensive bony defects.

A mildly painful wrist mass

Familial tumoral calcinosis (FTC) is a rare autosomal recessive disease characterized by progressive deposition of periarticular calcifications [1, 2]. It can be divided into hyperphosphatemic and normophosphatemic types depending on the serum phosphate level [3]. In the hyperphosphatemic type, the GALNT3 gene, which codes for a glycosyltransferase and FGF23 gene that codes for a phosphaturic protein, have been identified as the cause of phosphate dysregulation [3, 4]. In the less common normophosphatemic type, SAMD9 gene mutation causes dysregulation of endothelial cell and fibroblast function. A positive family history is present in 30–40 % of patients while the rest are sporadic [4]. FTC is most common in patients of African decent [1]. Typically, patients present in the first two decades of life with solitary or multiple painless periarticular “tumors” that reduce range of motion in the involved joints [2]. The periarticular swelling is painless unless there is nerve impingement. The overlying skin is usually intact. Occasionally, soft tissue ulceration with extrusion of chalky white material can be seen. Radiographically, lobulated, variably calcified, juxtaarticular masses in bursal distribution can be seen (Figs. 1, 2 and 3a). Extensor surfaces are commonly involved, with descending frequency of distribution at hip, elbow, shoulder, foot, and wrist. Less commonly, they happen in extraarticular regions without naturally occurring bursa including scalp, larynx, spine, and sacrum, where there is synovial metaplasia forming bursa-like structures in response to trauma [2, 5]. Sedimentation sign, which represents fluid–fluid levels caused by calcium layering, is classical [6] (Fig. 3b,c). Although the sedimentation sign is usually best appreciated in cross-sectional imaging, sometimes it can be evident only in ultrasound [7]. On CT imaging, lobulated cystic calcification that communicates with the bursa can be demonstrated. The appearance of homogeneity suggests a reduced metabolic activity and lower likelihood of growth [8, 9]. There should not be any erosion or destruction of adjacent bones. On MRI, FTC has a variegated appearance [2, 10]. In T1W The case presentation can be found at doi:10.1007/s00256-013-1710-8.

Surgical Ciliated Cysts May Mimic Radicular Cysts or Residual Cysts of Maxilla: Report of 3 Cases

Surgical ciliated cysts, or postoperative maxillary cysts, are benign cystic lesions induced after a surgical procedure in the maxillofacial area. It is a cystic lesion in the maxillary region that develops after radical sinus surgery to treat maxillary sinusitis. It is frequently reported in he Japanese literature, and most cases are related to revious Caldwell-Luc surgeries to treat maxillary sinustis. There are case reports of surgical ciliated cysts that eveloped after midface and bimaxillary orthognathic urgery, alveolar bone grafting, and maxillofacial trauma. It is believed that some cells of the respiratory ining are trapped during a surgical procedure or rauma. Subsequent cystic change of the trapped lining nd enlargement of the cyst from the osmotic difference ause destruction of adjacent bone and structures. As he cyst expands, it may affect the adjacent teeth. The linical scenario may be identical to a radicular cyst if a nonvital” tooth is involved. We present 3 cases of surgical ciliated cysts where the atients had previously undergone maxillary sinus sureries and later presented with cystic lesions in the axillary region similar to radicular cysts or residual ysts.

Giant Acral Melanoma on the Left Thumb of a Korean Patient

The acral regions of the limbs of Asians are predisposed to develop malignant melanoma, but giant-sized acral melanoma has not been previously reported in the Asian population. Giant-sized melanoma implies aggressive tumor invasion and so it is more difficult to achieve a therapeutic cure. A 56-year-old woman presented with a giant acral melanoma of the left thumb with concomitant bone destruction and axillary lymph node metastasis. The initial lesion was a subungual black macule on the left thumb that had grown into a giant 7.0x4.0x3.5 cm-sized melanoma over a 3 year period. The left thumb was amputated and the axillary lymph nodes were completely dissected. During the ensuing 3 months, she underwent adjuvant treatment with interferon-alpha-2a. The interesting feature of this case is that the large melanoma mass of this patient, which was accompanied with adjacent bone destruction and lymph node metastasis, had developed rapidly from a small black macule in the nail matrix, and this black macule was suspected to be a subungual melanoma.

A Comparison of Computed Tomography, Magnetic Resonance Imaging, and Digital Subtraction Angiography Findings in the Diagnosis of Infected Aortic Aneurysm

To characterize imaging findings from computed tomography, magnetic resonance imaging, and angiogram in patients with infected aortic aneurysm. We retrospectively reviewed the records of 21 patients (men, 17; women, 4) with proven infected aortic aneurysms and compared the imaging findings (computed tomography scans, n = 21; magnetic resonance images, n = 2; and angiograms, n = 2). Aneurysms were located in the descending thoracic aorta (n = 10; 47.6%), abdominal aorta (n = 6; 28.6%), aortic arch (n = 3; 14.3%), and thoracoabdominal aorta (n = 2; 9.5%). Aneurysms were saccular in 19 (90%) and fusiform in 2 (10%). Maximal diameters were greater than 10 cm in 2 patients (10%), 5 to 10 cm in 11 (52%), and less than 5 cm in 8 (38%). Average diameters were 6.5 cm in the aortic arch, 5.3 cm in the descending thoracic aorta, and 5.1 cm in the abdominal aorta. Obvious aortic wall calcification occurred in 19 patients (90%). Other features included disrupted calcification (n = 15; 71%), prominent and irregular wall thickening (n = 17; 81%), periaortic soft tissue mass (n = 15; 71%), rim enhancement (n = 18; 86%), periaortic gas (n = 7; 33%), periaortic stranding and fluid retention (n = 14; 67%), periaortic hematoma (n = 3; 14%), adjacent bone destruction (n = 1; 5%), pleural effusion (n = 12; 57%), and associated dissecting aneurysm (n = 2; 10%). Saccular aneurysms, adjacent soft tissue masses, rim enhancement, stranding, fluid, gas, and unusual adjacent bony destruction highly suggest infected aneurysm.

Diffusion-Weighted MR Imaging: Diagnosing Atypical or Malignant Meningiomas and Detecting Tumor Dedifferentiation

Atypical and malignant meningiomas are uncommon tumors with aggressive behavior and higher mortality, morbidity, and recurrence compared with benign tumors. We investigated the utility of diffusion-weighted (DW) MR imaging to differentiate atypical/malignant from benign meningiomas and to detect histologic dedifferentiation to higher tumor grade. We retrospectively compared conventional and DW MR images (b-value 1000 s/mm(2)) acquired on a 1.5T clinical scanner between 25 atypical/malignant and 23 benign meningiomas. The optimal cutoff for the absolute apparent diffusion coefficient (ADC) and normalized ADC (NADC) ratio to differentiate between the groups was determined by using receiver operating characteristic (ROC) analysis. Irregular tumor margins, peritumoral edema, and adjacent bone destruction occurred significantly more often in atypical/malignant than in benign meningiomas. The mean ADC of atypical/malignant meningiomas (0.66 +/- 0.13 x 10(-3) mm(2)/s) was significantly lower compared with benign meningiomas (0.88 +/- 0.08 x 10(-3) mm(2)/s; P < .0001). Mean NADC ratio in the atypical/malignant group (0.91 +/- 0.18) was also significantly lower than the benign group (1.28 +/- 0.11; P < .0001), without overlap between groups. ROC analysis showed that ADC and NADC thresholds of 0.80 x 10(-3) mm(2)/s and 0.99, respectively, had the best accuracy: at the NADC threshold of 0.99, the sensitivity and specificity were 96% and 100%, respectively. Two patients had isointense benign tumors on initial DW MR imaging, and these became hyperintense with the decrease in ADC and NADC below these thresholds when they progressed to atypical and malignant meningiomas on recurrence. ADC and NADC ratios in atypical/malignant meningiomas are significantly lower than in benign tumors. Decrease in ADC and NADC on follow-up imaging may suggest dedifferentiation to higher tumor grade.

Meckel's Cave Tuberculoma with Unusual Infratemporal Extension

The authors describe a rare case of intracranial tuberculoma of the Meckel's cave and cavernous sinus with extension into the infratemporal fossa causing widening of the foramen ovale and adjacent bone destruction. The rarity of the lesion and the unusual extension of the lesion are presented with a brief review of literature.

Aspectos clínico-tomográficos da mucocele com invasão orbitária

OBJETIVO: Avaliar e relacionar os achados clínico-radiológicos da mucocele orbitária. MÉTODOS: Análise clínica e de imagem referente a 166 pacientes com lesões expansivas da órbita examinadas com o tomógrafo Somaton DR da marca Siemens de terceira geração num período de 10 anos consecutivos em Hospital Universitário de referência. RESULTADOS: Os achados clínicos mais comuns foram tumoração e proptose do globo ocular. À tomografia computadorizada, o achado típico foi de massa com baixa densidade, originando-se em seios paranasais, com destruição óssea adjacente, invasão da órbita e deslocamento do globo ocular. CONCLUSÃO: O desenvolvimento da tomografia computadorizada foi decisivo no estudo da órbita pois propicia, por meio de exame radiológico altamente especializado, imagens de incrível fidelidade anatômica revelando informações sobre o processo patológico como sua localização, sua relação com as estruturas adjacentes e sua vascularização.

Intracranial Inflammatory Pseudotumors: MRI and CT Findings

Purpose : The purpose of this study was to describe the MR imaging and CT findings of intracranial inflammatory pseudotumors.Materials and Methods : We reviewed the MR imaging (n=8) and CT (n=4) studies of eight patients (M:F =4:4, mean age: 41 years) with pathologically proven intracranial inflammatory pseudotumor. The findings were then evaluated with regard to location, shape, MR signal intensity, CT density and degree of contrast enhancement of the lesion, surrounding parenchymal edema, adjacent bone change and the location of accompanying extracranial lesion.Results : In two patients, the parietal convexity was involved unilaterally, with no extracranial mass, and in the other six, the middle cranial fossa was involved unilaterally and extracranial mass was present. The lesion also involved the tentorium in four cases, the cavernous sinus in four, the anterior cranial fossa in one, and the posterior cranial fossa in one. The location of extracranial mass was the mastoid and middle ear cavity in two cases, the infratemporal fossa in two, both the infratemporal fossa and paranasal sinuses in one, and the orbit in one. MR images showed diffuse dural thickening in all eight cases, leptomeningeal thickening in four, and focal meningeal-based mass in two. As seen on T1 weighted images, the lesions were isointense to gray matter in eight cases, and on T2-weighted images were hypointense in seven cases and isointense in one. Marked homogeneous contrast enhancement was seen in all eight cases. The lesions seen on brain CT, performed in two cases, were isodense. Adjacent brain parenchymal edema and the destruction of adjacent bones were each seen in five cases.Conclusion : The characteristic MR findings of intracranial inflammatory pseudotumors are(1) diffuse dural thickening;(2) a focal meningeal-based mass which on T2-weighted images is seen as hypointense; and marked (3) contrast enhancement : these findings are, however, nonspecific. In order to differentiate these tumors, an awareness of these findings is, however, useful.