Clinics in diagnostic imaging (166)

A 68-year-old woman with poorly controlled diabetes mellitus presented to the emergency department with choreoathetoid movements affecting the upper and lower left limbs. Computed tomography of the brain did not show any intracranial abnormalities. However, subsequent magnetic resonance (MR) imaging of the brain revealed an increased T1 signal in the right basal ganglia, raising the suspicion of nonketotic hyperglycaemic chorea-hemiballismus. Management consisted of adjusting her insulin dose to achieve good glycaemic control. The patient subsequently recovered and was discharged after eight days. There are many causes of basal ganglia T1 hyperintensity, including hyperglycaemia in patients with poorly controlled diabetes mellitus. This case emphasises the importance of MR imaging in the early diagnosis of hyperglycaemia as a cause of chorea-hemiballismus, to enable early treatment and a better clinical outcome.     

Imaging features of an intraosseous arteriovenous malformation in the tibia

Primary intraosseous arteriovenous malformations (AVMs) are rare and have only been occasionally reported. We herein report a histologically proven case of primary intraosseous AVM in the tibia, which mimicked a fibrous tumour on radiography. This presentation carries a risk of triggering acute large haemorrhage through unnecessary biopsy. In intraosseous AVM, the magnetic resonance (MR) imaging features typical of a soft tissue AVM are absent, making diagnosis difficult. In this report, peculiar MR features in the presence of a connecting vessel between the normal deep venous system of the lower extremity and the tumour provide a clue for the early diagnosis of primary intraosseous AVM.     

糖尿病足的介入治疗进展

糖尿病足是糖尿病的严重并发症之一,是糖尿病患者致死和致残的重要原因。血管病变是导致糖尿病足的重要因素,随着医学影像学和介入放射学的发展,介入治疗发挥了重要作用,特别是小口径、长球囊的临床应用,降低了糖尿病足患者的截肢率,提高了患者的生活质量。手术前CT血管造影、磁共振血管造影准确了解糖尿病足患者下肢血管病变的范围、程度,对明确诊断、制订治疗方案、评价疗效及预后等至关重要。现就糖尿病足的介入治疗进展予以综述。     

Predictors of major lower limb amputation among type II diabetic patients admitted for diabetic foot problems

INTRODUCTION

Diabetes mellitus (DM) is the most common cause of amputations in Malaysia. This study aimed to identify the predictive factors for major lower limb amputation among patients with type 2 DM (T2DM) who were admitted to a hospital, in order to reduce its likelihood.

METHODS

This cross-sectional study involved 218 patients with T2DM who were admitted to Hospital Tengku Ampuan Afzan, Kuantan, Malaysia, for diabetic foot problems from June 2011 to July 2012. A form was developed to document the patients’ profiles, comorbidities, complications, investigations, treatment and clinical outcomes. The predictors for major lower limb amputations were determined using univariate and stepwise logistic regression analysis.

RESULTS

A total of 31 patients underwent major lower limb amputations (25 transtibial, 6 transfemoral). The following factors were found to be associated with the incidence of major lower limb amputations: T2DM duration ≥ 10 years, diabetic neuropathy, diabetic nephropathy, presentation with gangrene, diabetic foot conditions of Wagner grade 4 or 5, and necrotising fasciitis. Patients who underwent major amputations had significantly lower haemoglobin and albumin levels, and higher total white blood cell counts, erythrocyte sedimentation rates, and C-reactive protein, urea and creatinine levels. However, only T2DM duration ≥ 10 years, positive bacterial culture and albumin levels were significant on stepwise logistic regression analysis.

CONCLUSION

T2DM duration ≥ 10 years, positive bacterial culture and low albumin levels were found to be significant predictive factors for major lower limb amputation among patients with T2DM admitted for diabetic foot problems.     

Avoiding diagnostic pitfalls in mimics of neoplasia: the importance of a comprehensive diagnostic approach

Any medical diagnosis should take a multimodal approach, especially those involving tumour-like conditions, as entities that mimic neoplasms have overlapping features and may present detrimental outcomes if they are underdiagnosed. These case reports present diagnostic pitfalls resulting from overdependence on a single diagnostic parameter for three musculoskeletal neoplasm mimics: brown tumour (BT) that was mistaken for giant cell tumour (GCT), methicillin-resistant Staphylococcus aureus osteomyelitis mistaken for osteosarcoma and a pseudoaneurysm mistaken for a soft tissue sarcoma. Literature reviews revealed five reports of BT simulating GCT, four reports of osteomyelitis mimicking osteosarcoma and five reports of a pseudoaneurysm imitating a soft tissue sarcoma. Our findings highlight the therapeutic dilemmas that arise with musculoskeletal mimics, as well as the importance of thorough investigation to distinguish mimickers from true neoplasms.     

Unsuspected osteomyelitis in diabetic foot ulcers. Diagnosis and monitoring by leukocyte scanning with indium in 111 oxyquinoline

OBJECTIVE. The prevalence of osteomyelitis in diabetic foot ulcers is unknown. Early diagnosis of this infection is critical, as prompt antibiotic treatment decreases the rate of amputation. We therefore assessed the prevalence of osteomyelitis in 35 diabetic patients with 41 foot ulcers. We compared results of roentgenograms, leukocyte scans with indium In 111 oxyquinoline, and bone scans with the diagnostic criterion standards of bone histologic and culture findings. Leukocyte scans were repeated at 2- to 3-week intervals during antibiotic treatment. DESIGN. Cohort study. SETTING. Institutional and private, ambulatory and hospitalized patients. PATIENTS. Consecutive sample of 54 diabetic patients. Thirty-five patients with 41 foot ulcers were included. RESULTS. As determined by bone biopsy and culture, osteomyelitis was found to underlie 28 (68%) of 41 diabetic foot ulcers. Only nine (32%) of the 28 cases were diagnosed clinically by the referring physician. Underscoring the clinically silent nature of osteomyelitis in these ulcers, 19 (68%) of 28 occurred in outpatients, 19 (68%) of 28 occurred in ulcers not exposing bone, and 18 (64%) of 28 had no evidence of inflammation on physical examination. All patients with ulcers that exposed bone had osteomyelitis. Of the imaging tests, the leukocyte scan had the highest sensitivity, 89%. In patients with osteomyelitis, the leukocyte scan image intensity decreased by 16 to 34 days of antibiotic treatment and normalized by 36 to 54 days. CONCLUSION. The majority of diabetic foot ulcers have an underlying osteomyelitis that is clinically unsuspected. Leukocyte scans are highly sensitive for diagnosing osteomyelitis in diabetic foot ulcers and may be useful for monitoring the efficacy of antibiotic treatment. We recommend that diabetic patients with foot ulcers that expose bone should be treated for osteomyelitis. Diabetic patients with foot ulcers that do not expose bone should undergo leukocyte scanning, which eliminates the risk of bone biopsy in diagnosing osteomyelitis and allows for the diagnosis and treatment of this well-known but often silent precursor of lower extremity amputation.     

Intramuscular schwannoma: clinical and magnetic resonance imaging features

INTRODUCTION

Schwannomas that arise within the muscle plane are called intramuscular schwannomas. The low incidence of these tumours and the lack of specific clinical features make preoperative diagnosis difficult. Herein, we report our experience with intramuscular schwannomas. We present details of the clinical presentation, radiological diagnosis and management of these tumours.

METHODS

Between January 2011 and December 2013, 29 patients were diagnosed and treated for histologically proven schwannoma at the National University Hospital, Singapore. Among these 29 patients, eight (five male, three female) had intramuscular schwannomas.

RESULTS

The mean age of the eight patients was 40 (range 27–57) years. The most common presenting feature was a palpable mass. The mean interval between surgical treatment and the onset of clinical symptoms was 17.1 (range 4–72) months. Six of the eight tumours (75.0%) were located in the lower limb, while 2 (25.0%) were located in the upper limb. None of the patients had any preoperative neurological deficits. Tinel’s sign was present in one patient. Magnetic resonance (MR) imaging showed that the findings of split-fat sign, low signal margin and fascicular sign were present in all patients. The entry and exit sign was observed in 4 (50.0%) patients, a hyperintense rim was observed in 7 (87.5%) patients and the target sign was observed in 5 (62.5%) patients. All patients underwent microsurgical excision of the tumour and none developed any postoperative neurological deficits.

CONCLUSION

Intramuscular schwannomas demonstrate the findings of split-fat sign, low signal margin and fascicular sign on MR imaging. These findings are useful for the radiological diagnosis of intramuscular schwannoma.     

Hepatic tuberculosis: a rare cause of fluorodeoxyglucose hepatic superscan with background suppression on positron emission tomography

Fluorodeoxyglucose (FDG) hepatic superscan refers to the diffuse intense uptake of 18F-FDG in the liver on positron emission tomography (PET), with reduced physiological activity in the brain and heart. The common causes include lymphoma and metastasis. In this case report, we describe the imaging features of tuberculosis as a rare cause of FDG hepatic superscan. PET imaging may be the only clue to a diagnosis of hepatic tuberculosis, as other imaging modalities may demonstrate only nonspecific hepatomegaly. It is important to consider this entity in the differential diagnosis of patients presenting with FDG hepatic superscan and proceed with liver biopsy for a definitive diagnosis.     

Subacute sclerosing panencephalitis resembling Rasmussen’s encephalitis on magnetic resonance imaging

Subacute sclerosing panencephalitis (SSPE) is a rare, slowly progressing but invariably fatal disease that is related to a prior measles virus infection and most commonly affects paediatric patients. Magnetic resonance (MR) imaging is the modality of choice for determining such changes in white matter. SSPE typically demonstrates bilateral but asymmetric periventricular and subcortical white matter involvement. We herein report a rare case of unilateral white matter involvement in a 13-year-old boy with SSPE that closely simulated Rasmussen’s encephalitis. To the best of our knowledge, this is the first report of an atypical presentation on MR imaging in which SSPE was a rare cause of unilateral brain parenchymal involvement in a patient with intractable seizures.     

糖尿病足磁共振增强成像优化方案的探讨

目的探讨糖尿病足磁共振增强成像的优化方案。方法纳入20例糖尿病足患者,对患足进行增强后的三维小角度激发快速梯度回波血管成像序列(3DFLASH-MRA)、三维容积内插法屏气序列(3DVIBE)-水激励(WE)、T1WI二维自旋回波(2DSE)-压脂(FS)、T1WI二维快速自旋回波(2DTSE)-FS、T1 WI二维小角度激发快速梯度回波(2DFLASH)-FS序列的扫描,比较各序列在足部血管显示,静脉重叠,关节软骨显示,足底皮肤、跟骨、趾短屈肌、足背动脉、距跟关节软骨的信噪比(SNR)及对比率(CR)的差异。结果①在足部血管显示及静脉重叠评价方面,3DFLASH-MRA优于其余序列(P<0.05);②在对关节软骨的显示方面,3DVIBE-WE序列优于2DSE-FS、2DTSE-FS、2DFLASH-FS(P<0.05);③足底皮肤、跟骨、趾短屈肌、足背动脉、距跟关节软骨的CR及足底皮肤、足背动脉、距跟关节软骨的SNR在3D VIBE-WE序列上高于其余序列(P<0.05)。结论 3DVIBE-WE序列应作为糖尿病足增强T1WI序列的首选序列,并在足部血管显示方面能作为3DFLASH-MRA的补充序列。     

Imaging of acute cholecystitis and cholecystitis-associated complications in the emergency setting

Acute cholecystitis is a common cause of right upper quadrant pain in patients presenting at the emergency department. Early diagnosis and recognition of associated complications, though challenging, are essential for timely management. Imaging studies, including ultrasonography, computed tomography and magnetic resonance imaging, are increasingly utilised for the evaluation of suspected cases of cholecystitis. These investigations help in diagnosis, identification of complications and surgical planning. Imaging features of acute cholecystitis have been described in the literature and are variable, depending on the stage of inflammation. This article discusses the spectrum of cholecystitis-associated complications and their imaging manifestations. We also suggest a checklist for the prompt and accurate identification of complications in acute cholecystitis.     

37例糖尿病足住院患者统计分析

目的 了解本院糖尿病足住院患者的诊疗现状,为本地区糖尿病足的防控提供依据.方法 选取我院2010年8月-2013年8月出院病案首页诊断为糖尿病足病例,对入选病例进行统计处理及回顾性分析.结果 3年来共有糖尿病足住院患者37例,以60岁-79岁的患者最多,约占72.97％；其并发症或合并症以心脑血管及微血管疾病为主,约占86.48％；住院患者以内分泌科为最多,约占43.24％,其他散见于内外各科室；入院时各项检查不够完善,仅空腹血糖的监测较全.患者予以截肢或截趾的约占13.51％,放弃治疗的约占21.62％.结论 应加强糖尿病足的规范化诊疗及多科室相互协作,强化糖尿病足的健康教育,使患者及家属了解糖尿病足的危害,加强患者的足部护理及糖尿病足的早期预防.     

Dural metastasis of nasopharyngeal carcinoma: rare,but worth considering

Metastasis of nasopharyngeal carcinoma (NPC) to the dura, an extremely rare condition, can be symptomatically silent and mistaken for a benign entity radiographically. Missed diagnosis can lead to serious consequences or prove immediately fatal. We report a woman with dural metastasis of NPC that mimicked a meningioma on radiography. Craniectomy with tumour resection was performed due to rapid progression from the onset of symptoms to disability. The patient was still alive two years after surgery. This case emphasises the need to keep in mind the possibility of dural metastasis of NPC in patients with abnormal imaging features. This would not only avoid wrong and optimistic diagnosis, but also allow for appropriate treatment in a timely manner. To our knowledge, this is the first report of metastasis of NPC to the dura. We provide detailed information on the neoplastic lesion, which masqueraded as a benign entity and caused potentially fatal consequences.     

脂蛋白α检测对糖尿病足的诊断价值分析

目的探讨脂蛋白α检测对糖尿病足诊断的价值。方法以我院2009年1月-2012年12月间27例糖尿病足病患者为研究对象,将27例未患有糖尿病足病的糖尿病患者作为对照,比较两组患者在糖尿病相关生化指标和糖尿病足病相关脂蛋白指标间的差异。结果两组患者在TG、TC、HEL-C、LDL-C、FPG、ApoA、ApoB、ApoE含量方面无显著差异,观察组脂蛋白α浓度高于对照组,差异有统计学意义（P〈0.05）。在Logistic多因素回归分析中,对糖尿病患者是否发生糖尿病足病有较为显著的影响是患者的性别、糖尿病病程及脂蛋白α的含量。结论脂蛋白α可以作为糖尿病足病诊断的重要指标。     

Clinics in diagnostic imaging (158). Duodenal ectopic pancreas

A 46-year-old man presented with right loin tenderness following a road traffic accident. Computed tomography and magnetic resonance imaging showed a well-defined, smooth, enhancing oval lesion in the wall of the first part of the duodenum. The lesion was seen separately from the normal pancreas. It showed attenuation, intensity and enhancement similar to that of normal pancreas. Based on the imaging appearance, a diagnosis of ectopic pancreas was made. The patient underwent oesophagogastroduodenoscopy, endoscopic ultrasonography and fine-needle aspiration cytology of the lesion, which confirmed ectopic pancreatic tissue. Since the patient was asymptomatic, surgical resection was deferred. The embryologic origin, various locations, imaging appearance and clinical significance of ectopic pancreas are discussed.     

Clinics in diagnostic imaging (165)

Oesophageal rupture is a life-threatening complication of balloon tamponade for bleeding oesophageal varices. We herein describe the clinical course and imaging findings in a 33-year-old Indian man who had a Sengstaken-Blakemore (SB) tube inserted for uncontrolled haematemesis, which was unfortunately complicated by malposition of the gastric balloon with resultant oesophageal rupture. The inflated SB tube gastric balloon was visualised within the right hemithorax on chest radiography after the SB tube insertion. Further evaluation of the thorax on computed tomography confirmed the diagnosis of oesophageal rupture associated with right-sided haemopneumothorax. It is crucial for both the referring clinician and reporting radiologist to recognise early the imaging features of an incorrectly positioned SB tube gastric balloon, so as to ensure prompt intervention and a reduction in patient morbidity and mortality.     

Clinics in diagnostic imaging (159). Jejunal intussusception due to Peutz-Jeghers syndrome.

A 21-year-old woman presented with acute onset of upper abdominal pain. A diagnosis of Peutz-Jeghers syndrome (PJS) was made based on the clinical picture of perioral pigmentation with imaging findings of transient jejunojejunal intussusceptions and small bowel polyps, and confirmed by characteristic histopathological appearances of Peutz-Jeghers polyps. PJS is a rare hereditary condition characterised by unique hamartomatous polyps, perioral mucocutaneous pigmentations, and increased susceptibility to gastrointestinal and extraintestinal neoplasms. Patients usually present with recurrent abdominal pain due to intussusception caused by polyps. Other modes of presentations include rectal bleeding and melaena. We describe the imaging findings of PJS and provide a brief review of bowel polyposis syndromes. The latter are relatively rare disorders characterised by multiple polyps in the large or small intestine, with associated risk of malignancies and other extraintestinal manifestations. Awareness of the manifestations and early diagnosis of these syndromes is crucial to prevent further complications.     

Tension pneumocephalus

Tension pneumocephalus is a rare but treatable neurosurgical emergency. Prompt and accurate diagnosis of tension pneumocephalus requires a high index of clinical suspicion corroborated by imaging. Herein, we describe a case of extensive tension pneumocephalus in a patient who had undergone transsphenoidal surgery and repair of the sellar floor, with subsequent successful decompression. This case report discusses the pertinent imaging features of tension pneumocephalus and its management.     

糖尿病高危足筛查的意义及IWGDF筛查方法研究进展

糖尿病足是糖尿病最严重的并发症之一。糖尿病足最佳的治疗手段是预防,糖尿病高危足的筛查是糖尿病足预防的重要一环,通过筛查出高危足患者,进一步识别其危险因素,通过具有针对性的健康教育,提高患者护理知识,增强患者护理行为,能够有效地降低糖尿病足的发病率。通过简述糖尿病足发病状况、高危足状况并着重讲述国际糖尿病足工作组提供的高危足筛查方法,加强广大医务工作者对糖尿病足预防的意识。     

糖尿病足34例临床分析和治疗体会

目的探讨糖尿病足临床发病相关因素及综合治疗的疗效。方法对34例糖尿病足进行资料分析,采用中西医、内外科相结合的综合治疗,总结其疗效。结果34例糖尿病足经综合治疗后治愈率26.5%,总有效率73.5%,与糖尿病足级别有关。结论综合治疗疗效较好,但是糖尿病教育,糖尿病足早期诊断、早期治疗需进一步加强。