[The detecting value of virtual non-calcium technique of dual-energy CT for bone marrow edema around nontraumatic osteonecrosis of the femoral head].

Objective: To evaluate the value of virtual non-calcium (VNCa) technique of dual-energy CT (DECT) for detecting bone marrow edema (BME) around nontraumatic osteonecrosis of the femoral head (ONFH) using MRI as reference standard. Methods: Nontraumatic ONFH patients were prospectively studied in the Fourth Medical Center of Chinese PLA General Hospital from October 2022 to May 2023, and their MRI and DECT images were analyzed. The diagnostic efficiency of the subjective assessment of BME around ONFH by two radiologists in VNCa color-coded images were calculated using the MRI results as the reference standard. The BME ranges were compared between VNCa images and MRI. Traditional CT values and VNCa CT values were compared between normal bone marrow and BME. The receiver operator characteristic (ROC) curve was established based on the statistically different CT values, and the area under the curve (AUC) was calculated to find the threshold to distinguish normal bone marrow from BME and evaluate the diagnostic efficacy. Results: Thirty patients with ONFH were included, including 24 males and 6 females, aged (39±12) years. There were 18 bilateral hips and 12 unilateral hips, with a total of 48 hips, 34 hips of which showed BME on MRI. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of subjective detection of BME on VNCa color coded maps by two physicians were 97.1% (33/34) and 97.1% (33/34), 92.9% (13/14) and 71.4% (10/14), 97.1% (33/34) and 89.2% (33/37), 92.9% (13/14) and 90.9% (10/11), 95.8% (46/48) and 89.6% (43/48), respectively, with no statistical difference (all P>0.05).There was no statistical difference between VNCa color-coded images and MRI in the BME range (P=1.160). The traditional CT values measured by the two radiologists were in good agreement with VNCa CT values, with intraclass correlation coefficient (ICC) of 0.948 (95%CI: 0.908-0.971) and 0.982 (95%CI: 0.969-0.990), respectively. The traditional CT value of normal bone marrow was (400.7±82.8) HU, and that of BME was (443.7±65.7) HU, with no statistical difference (P=0.062). The VNCa CT value of normal bone marrow was (-103.1±27.8) HU, and that of BME was (-32.9±25.7) HU, with statistical difference (P<0.001). The AUC of distinguishing normal bone marrow from BME based on VNCa CT value was 0.958 (95%CI: 0.857-0.995). The best cut-off value was -74.5 HU, and when the VNCa CT value was higher than -74.5 HU, the sensitivity, specificity, PPV, NPV and accuracy of diagnosing BME were 97.1%, 92.9%, 97.1%, 92.9% and 95.8 %, respectively. Conclusion: The VNCa technique of DECT has high efficiency in detecting BME around ONFH, and can accurately demonstrate the range of BME.

[Neoadjuvant chemotherapy in the treatment of locally advanced olfactory neuroblastoma in 25 cases].

Objective: To evaluate the efficacy of neoadjuvant chemotherapy (NACT) in the treatment of locally advanced olfactory neuroblastoma (ONB), and to explore the factors related to the efficacy of NACT. Methods: A total of 25 patients with ONB who underwent NACT in Beijing TongRen Hospital from April 2017 to July 2022 were retrospectively analyzed. There were 16 males and 9 females, with an average age of 44.9 years (ranged 26-72 years). There were 22 cases of Kadish stage C and 3 cases of stage D. After multiple disciplinary team(MDT) discussion, all patients were treated sequentially with NACT-surgery-radiotherapy. Among them, 17 cases were treated with taxol, cis-platinum and etoposide (TEP), 4 cases with taxol, nedaplatin and ifosfamide (TPI), 3 cases with TP, while 1 case with EP. SPSS 25.0 software was used for statistical analysis, and survival analyses were calculated based on the Kaplan-Meier method. Results: The overall response rate of NACT was 32% (8/25). Subsequently, 21 patients underwent extended endoscopic surgery and 4 patients underwent combined cranial-nasal approach. Three patients with stage D disease underwent cervical lymph node dissection. All patients received postoperative radiotherapy. The mean follow-up time was 44.2 months (ranged 6-67 months). The 5-year overall survival rate was 100.0%, and the 5-year disease-free survival rates was 94.4%. Before NACT, Ki-67 index was 60% (50%, 90%), while Ki-67 index was 20% (3%, 30%) after chemotherapy [M (Q1, Q3)]. The change of Ki-67 before and after NACT was statistically significant (Z=-24.24, P<0.05). The effects of age, gender, history of surgery, Hyams grade, Ki-67 index and chemotherapy regimen to NACT were analyzed. Ki-67 index≥25% and high Hyams grade were related to the efficacy of NACT (all P<0.05). Conclusions: NACT could reduce Ki-67 index in ONBs. High Ki-67 index and Hyams grade are clinical indicators sensitive to the efficacy of NACT. NACT-surgery-radiotherapy is effective for patients with locally advanced ONB.

[Quantitative study of T1 weighted imaging labyrinthine high signal ratio based on magnetic resonance imaging in patients with unilateral sudden deafness accompanied by vertigo and tinnitus].

Objective: To explore the value of speculating etiology of the magnetic resonance imaging (MRI) T1 weighted imaging (T1WI) labyrinthine high signal ratio in patients with unilateral sudden deafness accompanied by vertigo and tinnitus and its relationship with hearing prognosis. Methods: Fifty-two patients with unilateral sudden deafness accompanied by vertigo and tinnitus who were admitted to Beijing Tongren Hospital Affiliated to Capital Medical University from January 2016 to July 2019 were collected, including 27 males and 25 females, aged (47.7±15.1) years. The inner ear MRI data of 52 patients (17 plain scan, 35 enhanced scan) with unilateral sudden deafness were retrospectively analyzed. Two radiologists independently measured the labyrinthine high signal intensity of the affected side and the contralateral normal side on T1WI and enhanced T1WI and calculated the signal ratio (the normal labyrinth signal was subtracted from the affected signal and then divided by the normal signal). The etiology of the enhanced group was judged based on two methods, including whether the abnormal high signal was enhanced or not (unenhancement indicated hemorrhage and enhancement indicated inflammation), and the locations of labyrinthine involvement on enhanced three-dimensional fluid attenuated inversion recovery (3D-FLAIR) (inflammation usually involved the perilymph spaces, while hemorrhage involved the perilymph and endolymph spaces). In the plain group, the locations of labyrinthine involvement on 3D-FLAIR was applied to infer the potential etiology. Results: The two methods presumed that 8 cases might be hemorrhage (22.9%, 8/35) and 27 be inflammation (77.1%, 27/35) in the enhanced group, which had a high consistency, while it was speculated that 7 patients might be hemorrhage (7/17) and 10 patients be inflammation (10/17) in the plain group. The measurement results of the two radiologists were highly consistent within and between the groups [the intraclass correlation coefficient (ICC) values were greater than 0.800]. The area under the receiver operating characteristic (ROC) curve (AUC) of the T1WI high signal ratio in the enhanced group for speculating etiology was 0.949 (P<0.01), when the predictive threshold value was 0.467, with a sensitivity of 96.3% and a specificity of 87.5%. It might be hemorrhage when the ratio was higher than the threshold value, otherwise it was inflammation. The T1WI labyrinthine high signal ratio was higher in the hemorrhage group than that of the inflammation group, and the hearing prognosis was worse (all P<0.05). The T1WI labyrinthine high signal ratio of the unrecovered group was higher than that of the recovered group (P=0.034). Conclusions: The etiology of labyrinthine high signal formation can be inferred by quantitative values combined with the involved sites. The high signal in the labyrinth indicates poor hearing prognosis, the higher the signal intensity, the greater the possibility of hemorrhage and the worse the hearing prognosis.

[Outcomes and quality of life evaluation following endoscopic endonasal approach for sinonasal malignancies].

Objective: To analyse the outcomes and the prognostic factors of patients with sinonasal malignancies following endoscopic endonasal approach, and to compare the pre- and post-operative quality of life. Methods: A retrospective single-center review of 79 patients who underwent endoscopic endonasal approach for sinonasal malignancies in Beijing Tongren Hospital from October 2004 to March 2017 was performed, including 51 males and 28 females, with a median age of 48 years. Data of demography, imaging (including nasal CT and MRI before operation), histopathology and treatment strategy were collected. Recurrence and distant metastasis were diagnosed according to endoscopic examination, MRI and general check-up after surgery. Pre- and post-operative quality of life scores were obtained by sinonasal outcome test-22, visual analog scale and anterior skull base surgery questionnaire. SPSS 22 software was used for statistical analysis. Results: The study consisted of 13 pathological types with sinonasal T1-T4 stage tumors, including cervical lymph nodes and/or distant metastasis. All patients underwent endoscopic endonasal approach surgery. After 43 months of median follow-up time, the overall, disease-free, and recurrence-free survival rates at 1, 3, 5 and 10 years was 97.4%, 92.5%, 92.5% and 83.7%; 83.2%, 68.3%, 56.8% and 33.6%; 84.5%, 66.6%, 58.0% and 34.4%, respectively. Postoperative recurrence was an independent risk factor affecting the overall survival rate (HR=8.852, P=0.044), and preoperative recurrence (secondary surgery) was an independent risk factor affecting the disease-free and recurrence-free survival rate (HR value was 2.237 and 2.095 respectively, P value was 0.029 and 0.047 respectively). After surgery, the olfaction and nasal scab got worse, while the nasal obstruction and breathing were improved. Conclusions: Endoscopic endonasal approach for sinonasal malignancies can achieve satisfactory outcomes, and has obvious advantages in improving the quality of life. Postoperative recurrence and preoperative recurrence are the prognostic factors.

[Magnetic resonance imaging study of endolymphatic hydrops based on 3D-FLAIR sequence after single-dose intravenous gadolinium injection].

Objective: To investigate the visualization of endolymph in patients with otogenic vertigo by intravenous administration of single dose of gadolinium contrast agents and magnetic resonance three-dimensional fluid-attenuated inversion recovery sequence (3D-FLAIR MRI), and further assess the extent of endolymphatic hydrops. Methods: From Beijing Tongren Hospital of Capital Medical University between October 2017 and June 2018, 30 patients (16 males, 14 females) with unilateral otogenic vertigo were involved in this study, with the age of 30 to 68 years, mean age of (53±10) years. Eight hours after intravenous administration of single dose (0.1 mmol/kg, body weight) of gadopentetate (Gd-DTPA), 3D-FLAIR sequence was performed in 30 patients. The location of endolymphatic hydrops was observed and then the degree of hydrops was quantitatively elevated by two radiologists. The consistency test was used to analyze the location and degree of endolymphatic hydrops in the two radiologists and the paired t-test was used to compare the difference between the affected and healthy side of endolymphatic spaces of the patients with otogenic vertigo. Results: In 30 patients, the gadolinium distributed in all parts of the perilymph inside the inner ear, and can accurately outline the boundaries of the peri-and endolymph. Twenty-six patients (26/30, 86.7%) were found to have unilateral endolymphatic hydrops, including 18 mild hydrops, 8 significant hydrops. The two radiologists had a very good agreement on the assessment of endolymphatic hydrops(kappa=0.864, ICC=0.959). In the 3D-FLAIR MR images of 26 patients with endolymphatic hydrops, the saccule (26/26, 100%) had a higher rate of hydrops than the cochlea and utricle(16/26, 61.5%; 14/26, 53.8%), and two radiologists had a very good agreement on the location of endolymphatic hydrops(kappa=0.820). Moreover, there was a significantly statistical difference between the affected and healthy area of the endolymphatic space in this study (P<0.01). Conclusion: The technique of 3D-FLAIR MR imaging through single dose intravenous gadolinium injection is feasible, which can estimate endolymphatic hydrops in patients with otogenic vertigo, and accurately classify the degree of hydrops.

[Value of the apparent diffusion coefficient in diffusion weighted imaging at 3.0T MR for differentiating lacrimal gland tumors].

Objective: To investigate the diagnostic value of apparent diffusion coefficient in diffusion weighted imaging at 3.0 T MR for the differentiation in the larcrimal gland tumors. Methods: A total of 73 cases, 36 males and 37 female; mean age 14-81(44±15)years, with lacrimal gland tumors confirmed by pathology in Beijing Tongren Hospital were retrospectively analyzed between January 2011 and April 2016.All cases underwent the preoperative routine MRI and DWI scan, the ADC values were measured in region of interest within the solid zone. The cases were divided into benign and malignant group by the histopathology, according the different pathological categories, the malignant cases were further divided into the epithelial and non-epithelial malignacy. The receiver operating characteristic curve (ROC) was constructed using various cut points of ADC for different parameters to confirm the diagnostic threshold value and evaluate the diagnostic efficacy. Results: There were totally 77 lesions in 73 cases, of which 69 involved unilateral lacrimal gland,4 bilateral lacrimal glands. The mean ADC value of malignant and benign masses in lacrimal gland was (1.36±0.16) and (0.90±0.30)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both(t=-8.319, P<0.01). The mean ADC value of epithelial and non-epithelial malignacy in lacrimal gland was (1.08±0.18) and (0.54±0.09)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both(t=11.988, P<0.01). The area under the ROC for distinguishing malignant from benign lesions was 0.940. Using an ADC value of 1.275×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 94.4%(34/36), specificity of 82.9%(34/41), accuracy of 88.3%(68/77). The area under the ROC for differentiating non-epithelial from epithelial malignacy was 1.0. Using an ADC value of 0.736×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 100%, specificity of 100%, accuracy of 100%. Conclusion: The ADC value is helpful in differentiation among different kinds of tumors in lacrimal masses.

Prevalence of pollen-induced allergic rhinitis with high pollen exposure in grasslands of northern China.

BACKGROUND: The aim of this study was to investigate the prevalence of epidemiologic and physician-diagnosed pollen-induced AR (PiAR) in the grasslands of northern China and to study the impact of the intensity and time of pollen exposure on PiAR prevalence. METHODS: A multistage, clustered and proportionately stratified random sampling with a field interviewer-administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count. RESULTS: A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05). CONCLUSION: Pollen-induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.

Ossifying inverted papilloma and ossifying polyp of the sinonasal tract: comparison of CT and MRI features.

AIM: To investigate the key imaging points in distinguishing ossifying inverted papilloma (IP) from polyps. MATERIALS AND METHODS: The native computed tomography (CT), conventional and enhanced MRI manifestations of 20 ossifying IPs and eight polyps, which were confirmed histopathologically, were retrospectively evaluated by two doctors majoring in head and neck imaging. RESULTS: A significant difference was detected between the two entities for the involved sites (p<0.05). Although two lesions had similar CT findings, the MRI features differed significantly (p<0.05). Twenty ossifying IPs demonstrated heterogeneously isointense with moderate gadolinium enhancement, and a convoluted "cerebriform" configuration. Seven ossifying polyps revealed low T1 and high T2 signal, with marginal enhancement, and one showed isointense with moderate enhancement. The ossification appeared as oval or striped bone-like high attenuation, which consisted of peripheral hyperattenuating cortical bone and central fat-like attenuation of the medullary cavity. The corresponding MRI findings of the ossifying regions were peripherally low signal and centrally high signal on both T1- and T2-weighted images. The occurrence of two key MRI features of cystic appearance and the "cerebriform" sign were significantly different between two entities (p<0.05). CONCLUSIONS: CT can better detect intralesional ossification, but MRI is the optimal imaging technique for discriminating between two disease entities.

[The characteristics of CT scan and MRI images of middle ear adenomas].

Objective:To analyze characteristics of CT scan and MRI images of middle ear adenomas,and provide pre-operation diagnosis and differential diagnosis combined with clinical manifestation.Method:Retrospective analysis of 8 cases of middle ear adenomas which were diagnosed and treated with surgery in Beijing Tongren Hospital between 2004 and 2014, patients' complain, clinical manifestation, physical examination, pure tone analysis, CT scan and MRI images were collected.Result:A total of 8 cases were included in this study with 5 females and 3 males. Age of onset ranged from 21 to 51 years old, with an average age of 37.5 years old, and middle age of 37 years old. All patients suffered from single side middle ear adenomas, 5 of left side and 3 of right side. All 8 patients suffered from hearing loss with tinnitus or stuffy feelings, 2 cases with otalgia, 1 with facial nerve paralysis. Physical examination showed 5 cases of bulging of tympanic membrane, 2 cases of out growth of mass into the external ear canal, and 1 with normal tympanic membrane. CT scan of 7 patients showed mass in tympanum and mastoid, with packaged ossicular chain and with no significant bone damage. 2 cases showed out growth of mass into the external ear canal, and 1 case showed limited mass in middle tympanum. MRI images of 5 cases showed equal T1 and T2 signals with intensifying in tympanum. Long T1 or equal T1 and long T2 signal in mastoid showed obstructive inflammation.Conclusion:Characters of middle ear adenomas includes mass in tympanum without bone damage in CT scan, and equal T1 and T2 signal with significant intensifying in tympanum in MRI images. Combined with clinical manifestation, this radiological information may provide benefit for pre-operation diagnosis.

[Porphyromonas gingivalis FimA genotype distribution among periodontitis patients with type 2 diabetes].

OBJECTIVE: To investigate the distribution differences of Porphyromonas gingivalis(Pg) FimA genotypes between periodontitis patients with and without type 2 diabetes for a better understanding of the relationship between diabetes and periodontitis. METHODS: Questionnaires and detailed periodontal examinations(6 sites per tooth) were conducted in 80 subjects with moderate-severe chronic periodontitis in the Department of Periodontology, Peking University School and Hospital of Stomatology. There were 40 type 2 diabetic patients and 40 systemicly healthy patients enrolled respectively. The periodontal parameters including plaque index(PLI), probing depth(PD), bleeding index(BI), attachment loss(AL) by 6 sites per tooth and numbers of missing teeth were also recorded. Pooled subgingival plaque samples using pocket method with Whatman No3 filterpaper were collectedat each of the 6 sites from one incisor and one molar. Pg and its FimA genotype distributions were investigated using DNA extrctedfrom plaque samples by PCR. RESULTS: Diabetic patients had a significantly higher score of PLI[2.35(0.58) vs 1.64(0.76),P<0.05] , while rest of periodontal indexes observed(PD, BI and AL) did not differ significantly between diabetic patients and systemicly healthy controls(P>0.05). The detection rate of Pg did not show statistically significant difference between the two groups(50% vs 60%,P>0.05). However, the proportion of FimA Ⅱ was significantly higher in diabetic group than systemicly healthy group(80% vs 42%,P<0.05). CONCLUSIONS: Type 2 diabetic patients were prone to be infected by highly virulent strains of Pg: FimA ⅡPg.

Routine and dynamic MR imaging study of lobular capillary hemangioma of the nasal cavity with comparison to inverting papilloma.

BACKGROUND AND PURPOSE: Lobular capillary hemangioma is an uncommon lesion, and its MR imaging appearance has not been fully characterized. The purpose of this study was to determine the MR imaging features of nasal lobular capillary hemangioma and contrast its imaging characteristics to inverting papilloma. MATERIALS AND METHODS: The MR imaging signals of 32 patients with histopathologically proven nasal lobular capillary hemangiomas and 53 patients with nasal inverted papillomas were retrospectively studied. The findings of dynamic contrast-enhanced MR imaging in 24 lobular capillary hemangiomas and in 53 inverted papillomas were also analyzed. The Monte Carlo exact test was used for comparison of the time-intensity curve patterns of lobular capillary hemangioma and inverted papilloma. RESULTS: All lobular capillary hemangiomas appeared to be homogeneously isointense to gray matter on T1-weighted images. On T2-weighted images, all lesions showed heterogeneous hyperintensity, and a thin peripheral isointense or hypointense ring was seen in 28 patients. All lesions showed marked enhancement on enhanced images, with the exception of enhancement of the T2 isointense or hypointense ring. Forty-three (81.1%) inverted papillomas had moderate heterogeneous T2 signal intensity, and a characteristic "cerebriform" appearance was detected in 45 (84.91%) of 53 inverted papillomas. The time-intensity curves showed a washout pattern in 18 and a plateau pattern in 6 patients, whereas inverted papillomas showed a washout pattern in 12, a plateau pattern in 35, and a persistent pattern in 6 patients. There was a statistically significant difference as to time-intensity curve pattern between the 2 groups (P < .05). CONCLUSIONS: Hyperintensity on T2-weighted images, marked enhancement of tumor with a nonenhancing thin peripheral ring, and a washout time-intensity curve pattern are characteristic MR imaging features of nasal lobular capillary hemangiomas.

Solitary fibrous tumor of the sinonasal cavity: CT and MR imaging findings.

SUMMARY: SFT is a rare lesion of the sinonasal cavity. We retrospectively reviewed 5 patients with histopathologically proved sinonasal SFTs to determine their CT and MR imaging features. All patients underwent paranasal sinus CT and MR imaging. Four SFTs occurred in the nasal cavity, and 1, in the maxillary sinus. All SFTs had well-defined margins, and the mean maximum diameter was 55 mm. On nonenhanced CT, 5 SFTs appeared homogeneously isoattenuating to gray matter. The most common manifestations of bony involvement were bony remodeling and thinning. On MR imaging, 5 SFTs were isointense to gray matter on T1-weighted images, and the lesions were isointense in 3 and hypointense in 2 patients on T2-weighted images. The lesions showed heterogeneously marked enhancement on postenhanced MR images. Four patients underwent dynamic contrast-enhanced MR imaging, and the TICs showed a washout pattern. A familiarity with the imaging findings of sinonasal SFT may help to diagnose this entity.

Imaging study of ossifying fibroma with associated aneurysmal bone cyst in the paranasal sinus.

OBJECTIVE: To determine the CT and MR imaging features of ossifying fibroma with aneurysmal bone cyst of the paranasal sinus. MATERIALS AND METHODS: We retrospectively reviewed 15 patients with histopathology-proven ossifying fibromas with aneurysmal bone cysts in the paranasal sinus. All 15 patients underwent CT and MR imaging. The following imaging features were reviewed: location, shape, margin, CT findings, and MR imaging appearances and time-intensity curve of dynamic contrast-enhanced MR imaging. RESULTS: Ossifying fibromas occurred in the maxillary sinus in one patient, sphenoid sinus in 2, frontal sinus in 3, frontoethmoid sinuses in 3, and ethmoid sinus in 6 patients. Ossifying fibromas showed an elliptic-shape and aneurysmal bone cysts revealed a multicystic appearance, with well-demarcated margins. On unenhanced CT, ossifying fibromas appeared isodense to gray matter with scattered calcifications in nine, ground-glass appearance in 6 patients and aneurysmal bone cysts showed mixed density. Ossifying fibromas appeared isointense to gray matter in 12 and slightly hypointense in three patients on T1-weighted images, and isointense in 4 and hypointense in eleven patients on T2-weighted images, with moderate or marked enhancement after administration of contrast material. The time-intensity curves of eight ossifying fibromas exhibited a rapidly enhancing and rapid washout pattern. The intracystic components of aneurysmal bone cysts showed heterogeneous signal intensity on MR images, with fluid-fluid levels identified clearly by T2-weighted images, without enhancement. The periphery and septa of aneurysmal bone cysts appeared isointense on MR images, with marked enhancement. CONCLUSIONS: Fluid-fluid levels within an elliptic-shape mass with scattered calcifications or ground-glass appearance is highly suggestive of this complicated entity in the paranasal sinus.

CT and MR imaging findings of periorbital lipogranuloma developing after endoscopic sinus surgery.

SUMMARY: Periorbital lipogranuloma is a rare complication after ESS and presently lacks specific imaging reports. The purpose of this study was to describe the CT and MR imaging features of periorbital lipogranuloma. We retrospectively reviewed 9 patients with histology-confirmed periorbital lipogranuloma. All 9 patients underwent CT and MR imaging. Five lipogranulomas were located in the right eyelid and 4 in the left eyelid, which extended into the extraconal space to some degree. The lesions displayed an irregular shape and had an ill-defined margin. Multiple, specked, or nodular foci containing fat were scattered within these lesions. The lesions demonstrated moderate heterogeneous contrast enhancement on contrast-enhanced MR imaging. The TICs showed a persistent pattern (type I) in 6 patients undergoing DCE MR imaging. Thus, an ill-defined, irregular-shaped periorbital mass with multiple foci containing fat, combined with an ESS history, can help to accurately diagnose this entity.

Imaging features of paediatric haemophilic pseudotumour of the maxillary bone: report of three cases and review of the literature.

OBJECTIVES: Haemophilic pseudotumour (HP) is an extremely rare lesion. The purpose of this study was to describe the CT and MRI features of maxillary bone HPs and introduce the key points to differentiate HP from the mimicking entities in the region. METHODS: We retrospectively reviewed three paediatric patients with histology-proven HPs arising from the maxillary bone. All three patients underwent CT and/or MRI. Combined with six previously reported cases in the literature, the imaging features were comprehensively analysed. RESULTS: All HPs showed a well-demarcated, multilobulated expansile osteolytic lesion in the maxillary bone. On non-enhanced CT, HPs appeared of mixed density relative to grey matter. The lesions appeared to have markedly heterogeneous signal intensity on both T(1) and T(2) weighted images, with septa-like enhancement following the administration of contrast material, which corresponded to blood products in various stages of evolution. The lesions caused cortical thinning and even focal disappearance and multiple bone septa were identified within the involved maxillary bone. Some HPs were associated with radiated periosteal proliferation, which can easily be misdiagnosed as a malignant bone tumour. CONCLUSION: A high index of suspicion for HP and a familiarity with imaging findings may help to accurately diagnose this rare entity.

MR evaluation of sinonasal angiomatous polyp.

BACKGROUND AND PURPOSE: SAP is a rare lesion of the sinonasal cavity, which may be misdiagnosed as a benign or malignant neoplasm. The purpose of our study was to comprehensively evaluate the MR imaging features of SAP. MATERIALS AND METHODS: Forty patients with SAP confirmed pathologically were retrospectively reviewed. Of the 40 patients undergoing MR imaging, 39 had postcontrast T1WI; 30, DCE MR imaging; and 17, DWI. The image features assessed included the location, shape, margin, size, signal intensity, and enhancement pattern on DCE MR imaging and ADC maps. RESULTS: All 40 SAPs originated from the maxillary sinus, but the lesions frequently extended into the ipsilateral nasal cavity (38/40), toward the choana (19/40), and into the nasopharynx (8/40). The lesions demonstrated hypointensity on T1WI and heterogenous hyperintensity on T2WI. All 40 lesions showed a peripheral hypointense rim on T2WI. Postcontrast MR imaging revealed marked heterogeneous nodular and patchy enhancement. Progressive enhancement was found on DCE MR imaging in 30 cases. The TIC showed a steady enhancement pattern in 3 cases, a rapidly enhancing and slow washout pattern in 6 cases, and a rapidly enhancing and rapid washout pattern in 21 cases. On DWI, the mean ADC value was (1.40 ± 0.20) × 10(-3) mm(2)/s. CONCLUSIONS: Distinctive features of SAP on conventional MR imaging include internal heterogeneous hyperintensity and a peripheral hypointense rim on T2WI, as well as strong nodular and patchy enhancement on postcontrast MR images. The progressive enhancement on DCE MR imaging can also suggest the diagnosis.

Mesenchymal chondrosarcoma of the orbit: CT and MRI findings.

AIM: To describe the computed tomography (CT) and magnetic resonance imaging (MRI) features of orbital mesenchymal chondrosarcomas (MCSs). MATERIALS AND METHODS: Six patients with histology-confirmed MCSs of the orbit were retrospectively reviewed. All six patients underwent CT and MRI. Imaging studies were evaluated for the following: (a) tumour location, (b) configuration, size, and margin, (c) CT attenuation and MRI signal intensity, and (d) secondary manifestations. Additionally, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI were analysed in five patients. RESULTS: Two MCSs arose in the right orbit and four in the left orbit. Five MCSs were located in the retrobulbar intraconal space and one in the extraconal space. All the lesions displayed a lobulate configuration and had a well-defined margin. The mean maximum diameter was 25.8 mm (range 15-36 mm). On unenhanced CT, the lesions appeared isodense to grey matter in six patients, with calcifications in five. Two patients showed inhomogeneous, moderate enhancement on enhanced CT. Six MCSs appeared isointense on T1-weighted imaging and heterogeneously isointense on T2-weighted imaging. The lesions showed significantly heterogeneous contrast enhancement. Five patients had DCE MRI and the TICs showed a rapidly enhancing and rapid washout pattern (type III). The following features were also detected: compression of the extra-ocular muscle (six patients, 100%); displacement of the optic nerve (five patients, 83.3%); and encasing globe (three patients, 50%). CONCLUSIONS: A well-defined, lobulate orbital mass with calcification on CT and, marked heterogeneous enhancement and type III TIC on MRI are highly suspicious of orbital MCSs.

Nasal cavity eosinophilic angiocentric fibrosis: CT and MR imaging findings.

BACKGROUND AND PURPOSE: EAF consists of exceedingly rare lesions and presently lacks specific imaging reports. The purpose of this study was to determine the CT and MR imaging features of nasal cavity EAF. MATERIALS AND METHODS: We retrospectively reviewed 6 patients with histology-proven EAF in the nasal cavity. All 6 patients underwent CT and 3 patients also underwent MR imaging. The following imaging features were reviewed: 1) location, 2) shape, 3) margin, 4) CT attenuation, and 5) MR imaging signal intensity. In addition, the accompanying changes and the TIC of the DCE MR imaging were analyzed. RESULTS: All occurrences of EAF were located at the anterior nasal cavity, arising from the nasal septum in 4 patients, with irregular shape, and the lateral nasal wall in 2, with oval configuration. The mean size was 29.8 mm (range 12-52 mm). On nonenhanced CT, EAF lesions appeared isoattenuated relative to gray matter. On the T1-weighted image, the lesions were isointense in 3 (100%) patients. On the T2-weighted image, the lesions were isointense in 1 (33.3%) patient and hypointense in 2 (66.7%) patients. Occurrences of EAF revealed moderate inhomogeneous contrast enhancement. Three patients underwent DCE MR imaging and the TICs exhibited a rapidly enhancing and slow washout pattern. One patient had bilateral lacrimal gland enlargement, which displayed low signal intensity on the T2-weighted image. CONCLUSIONS: A familiarity with imaging findings, including lesion location, isoattenuation and bony changes, and hypointensity on T2-weighted images may help to accurately diagnose this rare entity.

Fibrous dysplasia-like appearance of the frontal process of the maxilla on CT: prevalence in North China.

The frontal process of the maxilla occasionally shows a localized FD-like appearance. The purpose of this study was to determine its prevalence and findings on CT. A retrospective study of 1000 consecutive paranasal sinus CT scans was preformed on outpatients without a history of trauma or previous surgery in our hospital during 6 months. CT images were interpreted independently by 2 experienced head and neck radiologists on a PACS system in a bone window setting. Of the 1000 patients (546 males; 454 females), 51 (5.1%,41 males and 10 females) had an FD-like appearance in the frontal process of the maxilla. There was a statistically significant difference between sexes (P < .001). Twenty-nine (56.9%) entities arose from the right frontal process and 22 (43.1%) from the left frontal process. These entities, with well-defined margins, were located at the base of the frontal process of the maxilla, appearing as an ovoid or triangular configuration on axial-plane CT and as a spindle or elliptic shape on the coronal plane. The mean maximal diameter was 9.8 mm (range, 3.6-16.1 mm). These entities exhibited a pagetoid appearance (type I) in 37 (72.5%), a ground-glass appearance (type II) in 8 (15.7%), and a cyst-like appearance (type III) in 6 (11.8%) patients on CT. The FD-like appearance of the frontal process of the maxilla is not rare and can be readily detected by CT.

Insulin promoter DNA methylation correlates negatively with insulin gene expression and positively with HbA(1c) levels in human pancreatic islets.

AIMS/HYPOTHESIS: Although recent studies propose that epigenetic factors influence insulin expression, the regulation of the insulin gene in type 2 diabetic islets is still not fully understood. Here, we examined DNA methylation of the insulin gene promoter in pancreatic islets from patients with type 2 diabetes and non-diabetic human donors and related it to insulin expression, HbA(1c) levels, BMI and age. METHODS: DNA methylation was analysed in 25 CpG sites of the insulin promoter and insulin mRNA expression was analysed using quantitative RT-PCR in pancreatic islets from nine donors with type 2 diabetes and 48 non-diabetic donors. RESULTS: Insulin mRNA expression (p = 0.002), insulin content (p = 0.004) and glucose-stimulated insulin secretion (p = 0.04) were reduced in pancreatic islets from patients with type 2 diabetes compared with non-diabetic donors. Moreover, four CpG sites located 234 bp, 180 and 102 bp upstream and 63 bp downstream of the transcription start site (CpG -234, -180, -102 and +63, respectively), showed increased DNA methylation in type 2 diabetic compared with non-diabetic islets (7.8%, p = 0.03; 7.1%, p = 0.02; 4.4%, p = 0.03 and 9.3%, p = 0.03, respectively). While insulin mRNA expression correlated negatively (p < 1 × 10(-6)), the level of HbA(1c) correlated positively (p ≤ 0.01) with the degree of DNA methylation for CpG -234, -180 and +63. Furthermore, DNA methylation for nine additional CpG sites correlated negatively with insulin mRNA expression (p ≤ 0.01). Also, exposure to hyperglycaemia for 72 h increased insulin promoter DNA methylation in clonal rat beta cells (p = 0.005). CONCLUSIONS/INTERPRETATIONS: This study demonstrates that DNA methylation of the insulin promoter is increased in patients with type 2 diabetes and correlates negatively with insulin gene expression in human pancreatic islets.