MRI Findings of Arachnoiditis, Revisited. Is Classification Possible?

BACKGROUND: Prior imaging studies characterizing lumbar arachnoiditis have been based on small sample numbers and have reported inconsistent results. PURPOSE: To review the different imaging patterns of lumbosacral arachnoiditis, their significance, and clinical implications. STUDY TYPE: Retrospective. POPULATION: A total of 96 patients (43 women; average age 61.3 years) with imaging findings of arachnoiditis (postsurgical: N = 49; degenerative: N = 29; vertebral fracture: N = 6; epidural and subdural hemorrhage: N = 3, infectious: N= 1; other: N = 8) from January 2009 to April 2018. FIELD STRENGTH/SEQUENCE: Sagittal and axial T2-weighted Turbo Spin Echo at 1.5 T and 3 T. ASSESSMENT: Chart review was performed to assess the cause of arachnoiditis, and imaging was reviewed by two musculoskeletal and three neurology radiologists, blinded to the clinical data and to each other's imaging interpretation. Previous classification included a three-group system based on the appearance of the nerve roots on T2-weighted images. A fourth group was added in our review as "nonspecified" and was proposed for indeterminate imaging findings that did not fall into the classical groups. The presence/absence of synechiae/fibrous bands that distort the nerve roots and of spinal canal stenosis was also assessed. STATISTICAL TESTS: The kappa score was used to assess agreement between readers for both classification type and presence/absence of synechiae. RESULTS: Postsurgical (51%) and degenerative changes (30%) were the most common etiologies. About 7%-55% of arachnoiditis were classified as group 4. There was very poor classification agreement between readers (kappa score 0.051). There was also poor interreader agreement for determining the presence of synechiae (kappa 0.18) with, however, strong interreader agreement for the presence of synechia obtained between the most experienced readers (kappa 0.89). DATA CONCLUSION: This study demonstrated the lack of consensus and clarity in the classification system of lumbar arachnoiditis. The presence of synechia has high interreader agreement only among most experienced readers and promises to be a useful tool in assessing arachnoiditis. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

The value of diffusion weighted imaging and apparent diffusion coefficient in primary Osteogenic and Ewing sarcomas for the monitoring of response to treatment: Initial experience.

PURPOSE: To assess the value of using Apparent Diffusion Coefficient (ADC) mapping in Diffusion Weighted Imaging (DWI) when monitoring treatment response in pediatric Osteogenic and Ewing sarcomas and to correlate with level of necrosis on post-surgical excision pathology. METHOD: This retrospective study includes 7 Osteosarcoma and 8 Ewing sarcoma patients. Pre-treatment and post-treatment focal MRIs were evaluated for ADC values, tumor volumes and variability of both measurements. We also compared the measurement between Ewing and Osteosarcoma groups, as well as between good (=/>90 % necrosis post-excision) and poor (<90 % necrosis post-excision) responders. RESULTS: All measurements except Maximum ADC (p = 0.20) showed a statistically significant difference when comparing them before and after treatment. When we segregated our population according to pathologic complete response, there was no difference in ADC measurements, volumetric measurements or either variability between good (8 Patients) and poor responders (7 Patients). When comparing the before-after changes in our measurement between the Ewing sarcoma and Osteosarcoma cases, there was no significant difference in the change between pre and post treatment (Δ) Mean or Maximum ADC, or in Δtumor-volume when measured on STIR or SPIR T1 post-contrast sequences. Only the ΔMinimum-ADC showed a statistically significant difference (p < 0.02) in this group. CONCLUSIONS: ADC can potentially reflect cellular changes associated with chemotherapy use, reflecting a response to treatment. However, quantitative use of those parameters to dictate a change in management, treatment regimen or chemotherapy dose in order to target a good response (>/ = 90 % necrosis post-excision) needs further investigation.

Rare skeletal muscle metastasis from renal cell carcinoma: case report and review of the literature.

Renal cell carcinoma (RCC) is a tumor that usually metastasizes to lung, liver, bone and brain, but rarely to skeletal muscles. We report a case of an elderly man with a history of bilateral metachronous RCC for which he underwent curative bilateral nephrectomies and renal transplantation, was in remission, and presented with a large solitary skeletal muscle metastasis from the initial RCC, 3 years later.

Isolated delayed metastasis to the talus from Ewing's sarcoma.

Bone metastasis to the hands and feet, known as acrometastasis, is a very rare finding and tends to be associated with extensive metastasis. We herein report the case of a 14-year-old girl known to have a history of successfully treated Ewing's sarcoma arising from the ribs, who presented with a pathologically proven isolated metastatic lesion to the talus 7 years after achieving clinical and radiologic remission. We describe the imaging findings on MRI, CT scan and PET-CT. To our knowledge, talar metastasis from Ewing's sarcoma has been previously reported only twice in the English literature. Noteworthy is the fact that one of the previously reported lesions was considered a skip metastasis, and the other was under-described in terms of primary and secondary tumor location and time to metastasis. In addition, the overall imaging findings were rather suggestive of a benign lesion, particularly on CT scan.

Cortical bone invasion in non-transfusion-dependent thalassemia: tumefactive extramedullary hematopoiesis reviewed.

OBJECTIVE OF THE STUDY: To assess the prevalence of cortical bone invasion (CBI) with secondary extramedullary hematopoiesis (EMH) in patients with non-transfusion-dependent thalassemia (NTDT), to determine its predilection sites on thoracic and abdominal imaging, to determine whether there is an association between various clinical and hematological parameters, and to evaluate its various findings mainly on magnetic resonance imaging (MRI), in addition to computed tomography (CT) scans. MATERIALS AND METHODS: This is a retrospective cohort study of 57 patients with NTDT imaged by CT or MRI. Both clinical and laboratory data were gathered. An imaging scoring system was used to describe the appearance of CBI by MRI. RESULTS: Twenty-seven patients (47.4 %) were found to have CBI and EMH with the most common location being the thoracic spine. Splenectomy and lower hemoglobin level were found to be independent risk factors for its development. Most lesions were homogenous (70 %), had predominant red marrow signal (67 %), and well-defined margins (89 %). CONCLUSION: CBI and secondary tumefactive EMH are common findings in patients with NTDT, with distinct imaging and clinical characteristics. An increased risk was seen in patients with splenectomy and lower hemoglobin. The imaging scoring system described is helpful in diagnosing and describing this entity, hence precluding unnecessary biopsies.

Congenital infantile fibrosarcoma: Association with bleeding diathesis.

PATIENT: Male, 2 month FINAL DIAGNOSIS: Congenital infantile fibrosarcoma Symptoms: Bleeding Medication: Vincristine • actinomycin • cyclophosphamide Clinical Procedure: Surgical resection Specialty: Pediatric Oncology. OBJECTIVE: Diagnostic/therapeutic accidents. BACKGROUND: Congenital infantile fibrosarcoma (CIF) is a soft-tissue tumor occurring during the first 2 years of life, most commonly in the extremities. CIF is frequently initially misdiagnosed as a vascular tumor, but its association with bleeding and coagulopathy has not been well characterized. CASE REPORTS: We describe 2 infants with CIF presenting with bleeding and coagulopathy, requiring urgent intervention. Both patients did well; one underwent partial resection followed by chemotherapy, and the other received 2 cycles of chemotherapy followed by gross total resection. We also provide a review of all reported cases of coagulopathy in the setting of CIF in the English literature, uncovering an association that seems to be more prevalent in patients diagnosed in the neonatal period, with associated anemia and thrombocytopenia, and a significant mortality rate. CONCLUSIONS: CIF needs to be considered in the differential diagnosis of vascular congenital tumors, especially when there is evidence of bleeding, anemia, or thrombocytopenia.

Calcaneal osteosarcoma: a rare cause of heel pain in the paediatric population.

Osteosarcoma is the most common primary non-haemopoietic malignant bone tumour in children and adolescents. However, it rarely occurs in the calcaneus with only a few case reports in the literature. We report a case of a 14-year-old boy with calcaneal osteosarcoma, who presented with heel pain followed by swelling. The pain was initially thought to be related to a benign process and treated with analgesics, delaying the diagnosis. We discuss the clinical presentation, the differential diagnosis, multi-imaging and pathological findings of a calcaneal osteosarcoma, its clinical outcome and the importance of early diagnosis to improve outcome.

Cyclophosphamide and topotecan as first-line salvage therapy in patients with relapsed ewing sarcoma at a single institution.

The combination of cyclophosphamide and topotecan (cyclo/topo) has shown objective responses in relapsed Ewing sarcoma, but the response duration is not well documented. We reviewed characteristics and outcome of 14 patients with Ewing sarcoma, treated uniformly at a single institution and offered cyclo/topo at first relapse. Six patients (43%) had relapse at distant sites. All patients received first-line salvage therapy with cyclophosphamide 250 mg/m and topotecan 0.75 mg/m, daily for 5 days repeated every 21 days. The median number of cycles was 4 (range 1 to 10). All toxicities were manageable, the most common being transient cytopenias. There were also 4 episodes of febrile neutropenia, and 3 episodes of gross hematuria. Response was assessable in 13 patients and showed progressive disease in 6 (46%), stable disease in 4 (31%), and partial response in 3 (23%). Nine patients had local control, consisting of radical surgery in 2, radiation in 3, and a combination in 4 patients. Response, when it occurred, was maintained for a median of 8 months (range, 4 to 28 mo). Four patients (29%) are alive at 3, 7, 9, and 110 months after relapse; 1 is receiving cyclo/topo, 1 is on third-line therapy, and 2 are in second and fourth remission. The low toxicity of this combination, and the lack of sustained responses, warrant its investigation in combination with targeted or novel therapeutic agents in relapsed disease.

Correlation of non-mass-like abnormal MR signal intensity with pathological findings surrounding pediatric osteosarcoma and Ewing's sarcoma.

OBJECTIVE: The aim of this work was to determine the role of MRI in interpreting abnormal signals within bones and soft tissues adjacent to tumor bulk of osteosarcoma and Ewing's sarcoma in a pediatric population by correlating MR findings with histopathology. MATERIALS AND METHODS: Thirty patients met the inclusion criteria, which included (1) osteosarcoma or Ewing's sarcoma, (2) MR studies no more than 2 months prior to surgery, (3) presence of abnormal MR signal surrounding the tumor bulk, (4) pathological material from resected tumor. The patients received standard neoadjuvant chemotherapy. Using grid maps on gross pathology specimens, the abnormal MR areas around the tumor were matched with the corresponding grid sections. Histopathology slides of these sections were then analyzed to determine the nature of the regions of interest. The MR/pathological correlation was evaluated using Mann-Whitney U test and Fisher's exact test. RESULTS: Twenty-seven patients had osteosarcoma and three patients had Ewing's sarcoma. Of the studied areas, 17.4% were positive for tumor (viable or necrotic). There was no statistically significant correlation between areas positive for tumor and age, gender, signal extent and intensity on MRI, or tissue type. There was, however, a statistically significant correlation between presence of tumor and the appearance of abnormal soft tissue signals. A feathery appearance correlated with tumor-negative areas whereas a bulky appearance correlated with tumor-positive regions. CONCLUSIONS: MR imaging is helpful in identifying the nature of abnormal signal areas surrounding bone sarcomas that are more likely to be tumor-free, particularly when the signal in the soft tissues surrounding the tumor is feathery and edema-like in appearance.

Value of sagittal fat-suppressed proton-density fast-spin-echo of the knee joint as a limited protocol in evaluating internal knee derangements.

PURPOSE: The aim of the study was to determine the accuracy and observer agreement in the assessment of internal knee derangement using sagittal fat-suppressed proton-density fast-spin-echo (FS PD-FSE) compared with combined sagittal T1-weighted spin-echo, dual-proton-density, and T2-weighted spin-echo sequences and with arthroscopy. METHODS: One hundred eighteen patients undergoing routine knee magnetic resonance (MR) imaging had additional imaging with sagittal FS PD-FSE sequences. Menisci, cruciate ligaments, extensor tendons (ETs), bone marrow, osteoarthritic changes, soft tissue edema, joint effusion, and incidental tumors were analyzed. Magnetic resonance images were independently reviewed by 2 radiologists. Fifty patients underwent knee arthroscopy. Statistical analysis compared both imaging protocols with each other and with arthroscopy. Intrareader and interreader agreements were evaluated using κ analysis. Both protocols were compared with arthroscopy. RESULTS: Intrareader agreement was very high except for readings of the posterior cruciate ligament, ETs, and cartilage. Intrareader agreement did not differ significantly between the 2 readers except for ETs, bone marrow, and cartilage. Interreader percent agreements were high using both protocols and were not significantly different between the 2 readers except for posterior cruciate ligament. Compared with arthroscopy, both methods showed almost identical results regarding sensitivity, specificity, positive predictive value, and negative predictive value, except for cartilage where FS PD-FSE had increased sensitivity, whereas the combined protocol had increased specificity. CONCLUSIONS: Sagittal FS PD-FSE is comparable to our regular MR protocol in assessing internal knee derangement with an overall agreement of at least 93% on all sites except cartilage. It was also comparable to arthroscopy in assessing the cruciate ligaments and menisci, but had a low specificity for cartilaginous derangements. It can replace our 3 sagittal series comprising T1- and T2-weighted and proton-density-spin-echo sequences, hence saving time and cost.

Practical approach to the child presenting with back pain.

Back pain may be the presenting symptom of many children attending to pediatric health care settings. As such, awareness to the common etiologies of back pain in this subgroup of patients remains essential as it guides appropriate diagnosis. Although several clues may be derived from the child's history and physical examination, imaging techniques may be required to confirm the underlying diagnosis. This review summarizes the most commonly encountered causes of back pain in children and highlights diagnostic approaches that will ensure early diagnosis and intervention for a more favorable outcome.

The risk of local recurrence along the core-needle biopsy tract in patients with bone sarcomas.

INTRODUCTION: We evaluated the local recurrence rate (LRR) of bone sarcoma along the core-needle biopsy (CNB) tract in patients who underwent limb Salvage Surgery (LSS) following a diagnostic CNB performed irrespective of the planned surgical incision site and for which surgery did not involve any biopsy tract removal. METHODS: A retrospective review of 10 pediatric patients diagnosed with bone sarcoma using a computed tomography-guided core-needle biopsy, with evaluation of medical records, pathological specimens and radiological films from the date of diagnosis until the most recent follow-up. RESULTS: None of the patients experienced local recurrence during their follow up, despite the lack of biopsy site resection. CT scans of the involved extremities were negative for any suspicious lesions in all patients up until the most recent follow-up. CONCLUSIONS: Our study and review of the literature suggest that the incidence of tumor seeding the CNB tract in bone sarcoma patients is apparently low, and possibly negligible. CNB should be performed through the most direct approach to the tumor, and LSS can be performed safely through the standard approaches without excision of the biopsy tract.

The impact of zoledronic acid on regenerate and native bone after consolidation and removal of the external fixator: an animal model study.

We investigated the role of zoledronic acid on the regenerate and native bone after consolidation and removal of the external fixator in a rabbit model of distraction osteogenesis using 28 New Zealand white rabbits. The rabbits were randomly distributed into two groups. The first group received three doses of zoledronic acid (ZA) 0.1 mg/kg subcutaneously at weekly intervals while the second group received injections of sterile saline. Distraction started on day 7 at a rate of 0.8 mm/day for 12 days. At week 3 the average lengthening, regenerate density, and regenerate continuity were comparable between the two groups. At week 11 the regenerate in the treated group had a significant increase in Bone Mineral Density (BMD) and Bone Mineral Content (BMC) compared to the placebo group. On axial compression, the regenerate showed an increase in the peak load and a higher modulus of elasticity in the treated group. At 6 months, radiographs demonstrated signs of osteopenia of the proximal metaphysis in the control group, and failure of new bone formation around the pin sites in the treated group. BMC and BMD value differences between the two groups were not statistically significant. Histologically, there was persistence of more bone trabeculae in the medullary canal of the regenerate with the persistence of the pin-holes in the treated group. Mechanically, the regenerates in the treated group remain stronger in resisting the axial compression. The proximal fragment in the treated group exhibited a statistically significant decrease in the peak load, toughness and efail %. In conclusion, bisphosphonate-treated rabbits have a stronger regenerate during distraction, and directly after removal of the fixator. They do not develop disuse osteopenia in their lengthened tibia. This treatment may shorten the time in the external fixator and prevent fragility fractures in the treated extremity. However, its long-term safety has not yet been established.

Abdominal complications of chemotherapy in pediatric malignancies: imaging findings.

OBJECTIVE: To describe the imaging findings of abdominal complications caused by chemotherapy in pediatric cancer patients. SUBJECTS AND METHODS: Radiology studies of 243 patients treated in our Children Cancer Center were reviewed, 164 of whom had abdominal studies. Medical records of 54 patients with abnormal imaging findings were studied. RESULTS: Ultrasound and/or CT findings showed the following complications: (1) gallbladder sludge/crystals (n=13), gallstones (n=8), cholecystitis (n=3); (2) liver steatosis (n=23), siderosis (n=1), veno-occlusive disease (n=2); (3) pancreatitis (n=7); (4) typhlitis (n=12), esophagitis (n=2). CONCLUSION: Awareness of these complications is essential for appropriate management, decreasing their mortality and morbidity.

Abdominal manifestations of multiple myeloma: a retrospective radiologic overview.

BACKGROUND: Abdominal manifestations of multiple myeloma (MM) are rare. Herein, the authors study the radiologic characteristics of such involvement because these findings are usually missed by the radiologist and oncologist. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 202 patients with MM treated at our institution. A total of 192 patients underwent > or = 1 abdominal imaging studies (ultrasound, computed tomography, magnetic resonance imaging), which were correlated with histopathology, when available. RESULTS: Eleven patients (5.72%) had lesions within 13 abdominal sites: liver (n = 4); pancreas (n = 3); peritoneum (n = 2); kidney, stomach, adrenal gland, and retroperitoneum (n = 1), respectively. Cytopathologic diagnosis was available in 5 cases. The remaining cases were considered to have myeloma deposits as a result of previous normal studies and the absence of other primary disease. The imaging findings were nonspecific. CONCLUSION: Myeloma deposits within the abdomen are rare. Although the imaging findings are nonspecific, oncologists and radiologists should be aware of their common characteristics.

Generalized dysplasia epiphysealis hemimelica with contralateral sacro-iliac joint involvement.

Dysplasia epiphysealis hemimelica (or Trevor's disease) is a rare developmental bone dysplasia characterized by benign osteocartilaginous overgrowth involving one or multiple epiphyses, usually of a single lower extremity. It is classified as localized form, classical form (most common), and generalized form. In this report we describe a case of generalized form of dysplasia epiphysealis hemimelica with involvement of the contralateral sacroiliac joint, which is an extremely rare presentation.

Left-sided cervical aortic arch associated with pseudocoarctation, aneurysm formation, and anomalous left brachiocephalic vein: appearance on MDCT and MR angiography.

Cervical aortic arch (CAA) is a rare congenital aortic anomaly. It can be associated with several cardiovascular abnormalities including aortic aneurysm, valvular disease, and pseudocoarctation. In this report, we present a case of CAA with combined association of both aneurysm formation and pseudocoarctation. This combination of anomalies is extremely uncommon, described in only 4 cases in the literature. In addition, our patient had an anomalous subaortic left brachiocephalic vein that, to our knowledge, was not previously described in the literature to be associated with CAA. The radiographic, multidetector computed tomography scan, and magnetic resonance angiography imaging findings are presented.