Testing of adult and paediatric ventilators for use in a magnetic resonance imaging unit

We have assessed the performance of a series of ventilators (modified versions of the ventiPAC, paraPAC and babyPAC ventilators; SIMS pneuPAC Ltd, Luton, UK) in a magnetic resonance imaging (MRI) scanning environment, with MR safety and compatibility issues being addressed. Following initial modifications to remove ferromagnetic components and replace them with MR-safe materials, all three ventilators performed well in a series of tests in static magnetic fields up to 2 T. Ventilator performance was unaffected by static fields, switching gradients or radio frequency fields within the MR suite. Furthermore, the devices produced no degradation of image quality when used during MR scanning. We discuss management strategies for the care of critically ill ventilated patients during MR procedures.     

Paediatric MRI

General anaesthesia is frequently necessary in infants and small children undergoing magnetic resonance imaging (MRI), because of the imaging techniques, MRI environment and potential need for breath-holding to facilitate imaging. The MR suite is a challenging environment for the anaesthetist, carrying risks such as remote location, unique features of the MR scanner and patient-related factors. Understanding the implications of the MRI environment will facilitate ensuring the safety of the patient. In addition, the expertise of the anaesthetist can make the difference between a diagnostic image filled with an artefact and one of superior quality. This review examines developments in MRI technology including sequences, the magnets used, the use of contrast and those aspects of paediatric MRI scanning where the anaesthetic technique is particularly important.     

Versatile Intraoperative MRI in Neurosurgery and Radiology

Summary. Summary.   Background: Several models for the application of intra-operative magnetic resonance imaging (IMRI) have recently been reported, most of them unique. Two fundamental issues need to be addressed: optimal use of the scanner to ensure a wide base for research, development and clinical application, and an organisational model that facilitates such use.   Method: While in our setting the IMRI project was initiated by the neurosurgeons, the need for wider use of the facilities was recognised since the beginning of the planning phase in 1996. An organisational model was developed that allowed for development of neurosurgical applications, radiological imaging, and radiological interventions and for the research and development work of the vendor. A resistive 0.23 T MR scanner was installed in a dedicated operating room environment. Unique to this scanner is the ability to turn off the magnet, allowing for normal OR activities and devices, and to turn on the magnet as needed with a relatively short six-minute ramp up time. A staged surgical technique was perfected, allowing for transfer of data to the neuronavigator outside the scanner during surgery. In neurosurgery, IMRI was used as one part of a neuronavigational system that included ultrasound imaging, intra-operative cortical stimulation during awake procedures, electrocorticography and two neuronavigators.   Findings: 34 neurosurgical cases included 27 brain tumour resections, 5 brain tumour biopsies, 1 extirpation of an arterio-venous malformation, and 1 haematoma evacuation. The scanner could also be used for normal clinical imaging where obese patients, children, claustophobic patients and postoperative control examinations were the major groups. The radiologists performed 110 interventions, including bone and abdominal biopsies, nerve root infiltrations and local pain therapies, with the optical needle tracking system under continuous MRI guidance. The organisational model allowed frequent use of the facilities for both neurosurgery and radiology and continuous development of the facilities. Intra-operative ultrasound was used in 20 tumour resections and in two open brain biopsies. This resulted in reduction of the number of MR imaging sessions during surgery. Five of the 27 resections were performed as awake craniotomies with cortical stimulation. For two of the resections, electrocorticography and depth electrode registrations were used. Furthermore, various non-MRI-compatible instruments and devices were used.   Interpretation: Intra-operative MRI is an imaging tool that can be useful especially in the context of neuronavigation. A scanner that can be turned off during surgery is particularly appropriate for neurosurgery. The concept of joint use of such facilities with other clinicians is mutually worthwhile.     

Initial clinical experience with real-time transrectal ultrasonography-magnetic resonance imaging fusion-guided prostate biopsy

OBJECTIVE

To evaluate the feasibility and utility of registration and fusion of real‐time transrectal ultrasonography (TRUS) and previously acquired magnetic resonance imaging (MRI) to guide prostate biopsies.

PATIENTS AND METHODS

Two National Cancer Institute trials allowed MRI‐guided (with or with no US fusion) prostate biopsies during placement of fiducial markers. Fiducial markers were used to guide patient set‐up for daily external beam radiation therapy. The eligible patients had biopsy‐confirmed prostate cancer that was visible on MRI. A high‐field (3T) MRI was performed with an endorectal coil in place. After moving to an US suite, the patient then underwent TRUS to visualize the prostate. The US transducer was equipped with a commercial needle guide and custom modified with two embedded miniature orthogonal five‐degrees of freedom sensors to enable spatial tracking and registration with MR images in six degrees of freedom. The MRI sequence of choice was registered manually to the US using custom software for real‐time navigation and feedback. The interface displayed the actual and projected needle pathways superimposed upon the real‐time US blended with the prior MR images, with position data updating in real time at 10 frames per second. The registered MRI information blended to the real‐time US was available to the physician who performed targeted biopsies of highly suspicious areas.

RESULTS

Five patients underwent limited focal biopsy and fiducial marker placement with real‐time TRUS‐MRI fusion. The Gleason scores at the time of enrolment on study were 8, 7, 9, 9, and 6. Of the 11 targeted biopsies, eight showed prostate cancer. Positive biopsies were found in all patients. The entire TRUS procedure, with fusion, took ≈10 min.

CONCLUSION

The fusion of real‐time TRUS and prior MR images of the prostate is feasible and enables MRI‐guided interventions (like prostate biopsy) outside of the MRI suite. The technique allows for navigation within dynamic contrast‐enhanced maps, or T2‐weighted or MR spectroscopy images. This technique is a rapid way to facilitate MRI‐guided prostate therapies such as external beam radiation therapy, brachytherapy, cryoablation, high‐intensity focused ultrasound ablation, or direct injection of agents, without the cost, throughput, or equipment compatibility issues that might arise with MRI‐guided interventions inside the MRI suite.     

Use of i-gel in magnetic resonance imaging

Anesthesia for magnetic resonance imaging (MRI) requires special equipment that can be used in the presence of a magnetic field. Endotracheal tube and various laryngeal mask airway devices have a variable quantity of ferromagnetic material in the pilot balloon that could reduce image quality and result in artifacts. The i-gel is a reliable, easily inserted airway device, and causes minimal interference in image quality. We used i-gel in 10 anaesthetized adult patients undergoing MRI. The quality of image, evidence of airway, tongue, and dental trauma were assessed throughout the procedure. All scans were diagnostically adequate. Therefore, we concluded that i-gel causes the least ferromagnetic interference compared with other devices and improves the quality of imaging and produces minimal artifact while scanning.     

Magnetic resonance imaging in the early phase of pyogenic spondylitis: A report of four cases

Magnetic resonance imaging (MRI) is useful for the early diagnosis of pyogenic spondylitis, because it clearly demonstrates edema and inflammatory changes. However, in four of our patients, MRI revealed no clear abnormality and it was difficult to make a diagnosis at the first hospital visit; evidence of pyogenic spondylitis was obtained later. Changes on plain roentgenogram and MRI were investigated at various times over the course of the disease in these patients. Since abnormalities may not be detected by MRI in the early phase of this disease, we recommend that imaging be repeated after at least 2 weeks if no abnormalities are noted at the first hospital visit in patients in whom this disease is suspected because of clinical or laboratory findings.     

Imaging of chondral defects

Because of its superior soft tissue contrast, magnetic resonance imaging (MRI) has replaced conventional techniques in the evaluation of articular cartilage. Various MR pulse sequences exist that provide accurate, reproducible evaluation of articular cartilage, obviating the need for intraarticular contrast injection. In the preoperative setting, such imaging helps to identify those patients with chondral lesions suitable for arthroscopic treatment. Following therapeutic intervention, MRI is an effective medium to assess long-term follow-up of the individual treatment regimen.     

Magnetic Resonance Imaging of the Breast as a Problem‐solving Method: To Be or Not to Be?

The use of dynamic magnetic resonance imaging (MRI) of the breast as a complementary problem‐solving tool was explored in a heterogeneous population sample. A total of 3,076 patients that underwent breast MRI examination between January 2008 and June 2012 in our center were screened retrospectively. Of these, 868 met the following inclusion criteria and were considered eligible for the study: available data on clinical signs, symptoms and on the results of mammography and ultrasound examinations in medical records; at least 1 year of follow‐up; and documented pathology findings. Lesions with a stable course over a follow‐up period of at least 12 months were considered benign. MRI was suggestive of a suspicious abnormality (BI‐RADS 4) or highly suggestive of malignancy (BI‐RADS 5) in 129 (15%) of 868 patients, leading to a biopsy examination in these cases. On the other hand, MRI findings were considered normal in 739 (85%) subjects based on normal (BI‐RADS 1), benign (BI‐RADS 2) or probably benign (BI‐RADS 3) findings. Of the 129 patients undergoing a histopathologic examination based on MRI findings, 63 were diagnosed with cancer, and in 66, the biopsy proved to be benign. Forty of the 63 patients (40/63) with a diagnosis of malignancy and 34 of the 66 patients (34/66) with a benign diagnosis had been categorized as BI‐RADS 4 with conventional methods. A total of 23 patients with BI‐RADS category of 0 to 3 according to conventional methods were diagnosed as having cancer with MRI. In six of these, the family history was positive. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of MRI for the detection of cancer were 100%, 92%, 52%, and 100%, respectively. In cases with inconclusive findings on conventional imaging studies or in patients with clinical/radiological suspicion of malignancy, MRI should be more effectively used as a problem‐solving approach owing to its high sensitivity and NPV in this condition. Use of MRI as a problem‐solving method in such cases may decrease rather than increase unnecessary biopsy procedures and patient anxiety.     

Accuracy of ultrasonography and magnetic resonance imaging in the diagnosis of non-palpable testis

BACKGROUND: Studies were needed to evaluate the accuracy of ultrasonography (US) and magnetic resonance imaging (MRI) for diagnosing non-palpable testis, and to study the clinical usefulness of US and MRI before surgical exploration. METHODS: Fifty-six patients with non-palpable testis aged 1--12 years were examined between 1993 and 2002. Forty-six patients (55 non-palpable testes) underwent US. Forty patients (47 non-palpable testes) were examined using MRI. Both US and MRI were used in 29 patients (34 non-palpable testes). We used Fisher's exact probability test to compare the results of these graphic examinations with the surgical or laparoscopic findings for the non-palpable testis. RESULTS: Ultrasonography had a sensitivity of 76%, a specificity of 100%, and an accuracy of 84% in the diagnosis of non-palpable testis, whereas MRI had a sensitivity of 86%, a specificity of 79%, and an accuracy of 85%. CONCLUSIONS: There were no statistically significant differences in the accuracy rates of US and MRI for diagnosing non-palpable testis. Laparoscopy or inguinal exploration should be performed even if these graphic examinations demonstrate the absence of a testis, because some patients with a non-palpable testis were found to be false negatives. We recommend US as the first step after clinical examination, and MRI could be performed when the US findings are negative preoperatively for a non-palpable testis.     

3.0T术中磁共振成像引导下唤醒麻醉联合术中语言皮质定位技术在语言区脑胶质瘤手术中的应用

目的 评价3.0 T术中磁共振成像(iMRI)下采用唤醒麻醉联合术中语言皮质定位技术辅助语言区脑胶质瘤切除的临床有效性.方法 2010年12月至2011年4月以集成3.0 TiMRI数字一体化神经外科手术中心为平台,采用唤醒麻醉、改良手术铺巾技术、联合直接电刺激语言皮质定位和iMRI实时影像神经导航,对11例右利手患者实施左侧语言区脑胶质瘤切除.术中采用简易语言任务模式,包括语言流利度、图片命名和文字测读,评估患者语言功能状况.围手术期采用汉语失语检查法,评估新技术的临床有效性.结果 通过iMRI实时影像导航,6/11的患者可以定量提升胶质瘤切除范围,其中影像学全切除率提高3/11,最终肿瘤全切除7例,次全切除4例.语言皮质定位阳性率为8/11.患者术后1周内出现一过性失语率为4/11,随访至术后1个月,所有患者语言功能均恢复到术前水平或以上;围手术期患者无肢体运动功能障碍.结论 应用3.0 T超高场强iMRI实时影像导航可在术前设计脑胶质瘤个体化手术方案,术中精确定位病灶,等体积定量切除肿瘤,提高肿瘤切除率;在唤醒麻醉下实施术中皮质电刺激定位语言区,能最大程度保护患者语言皮质,避免出现不可逆的语言功能损伤,提高术后社会生活质量.

Abstract：

Objectives To evaluate preliminary clinical experience for combining awake craniotomy and intraoperative language brain mapping within the integrated 3.0 T intraoperative maguetic resonance imaging (iMRI) suite.Methods From December 2010 to April 2011,11 right hand-dominant patients with left glioma were involved in, or adjacent to, eloquent cortex was carried out awake craniotomies with cortical stimulation within an integrated 3.0 T iMRI suite.Aphasia battery of Chinese was used to test the language function before the operation.During the procedure, after the occipital, temporal, and supraorbital nerves were blocked by the anesthesiologists, the head was fixed with a custom high-field MRI-compatible head holder.The skull and dura was opened as usual and language brain mapping was then performed.Language testing followed a set protocol:counting numbers from 1 to 50, naming objects, reading single words.Resection of the tumor was guided by neuronavigation system and continued until eloquent areas were encountered or the margin of assessment was reached.An interdissection MRI was aquired to evaluate the glioma removal in a movable MRI scanner after minimal draping. Meanwhile, adverse effects caused by electrical stimulation and iMRI were recorded.The follow-up speech tests were assessed on 7th day and 1 month at least after the operation.Results The combined use of 3.0 T iMRI and awake craniotomy was performed safely in all patients.No adverse effects were reported.The duration of surgery was prolonged by 2 to 4 h.The patients' perception of iMRI during surgery was favorable.First-look MRI studies led to further resection attempts in 6/11 cases as well as a 3/11 increase in the number of gross-total resections.One week after surgery, baseline language function worsened in 4 cases. However, no patients had a persistent language deficit one month after surgery. Conclusions Awake craniotomy and direct cortical electrical stimulation can be performed safely and effectively within a 3.0 T iMRI suite.The combination of high-field iMRI and awake craniotomy may facilitate safe removal of eloquent glioma.     

功能MRI评价鼻咽癌放射治疗后早期脑损伤研究进展

颞叶放射性脑损伤是放射治疗鼻咽癌后最易发生且影响预后的严重神经系统并发症。早发现、早治疗是控制放射性脑损伤病情进展的关键。但当常规影像学检查发现异常时,脑损伤常已发展至不可逆转的中晚期阶段。功能MRI通过多个参数定量反映活体组织微观结构改变,为临床早期诊断放射性脑损伤提供可靠的影像学依据。目前用于评估放射性脑损伤的功能MRI技术有磁共振波谱成像、灌注加权成像、弥散加权成像、扩散张量成像及扩散峰度成像等。本文对功能MRI评价放射治疗鼻咽癌后早期脑损伤研究进展进行综述。     

The role of gadolinium enhanced magnetic resonance imaging for children with suspected acute pyelonephritis

PURPOSE: The diagnosis of pyelonephritis is primarily clinical. However, the history and physical findings can be confusing in children, leading to adjunctive nuclear renal cortical scintigraphic studies (99mtechnetium dimercapto-succinic acid [DMSA]) to confirm the diagnosis. Nonetheless, ambiguity occurs when differentiating between acute pyelonephritis and chronic scarring. We report our initial experience with gadolinium enhanced inversion recovery magnetic resonance imaging (MRI) to diagnose acute pyelonephritis. MATERIALS AND METHODS: Nine patients 7 months to 18 years old (mean age 81 months) underwent MRI to confirm radiographically a clinical suspicion of acute pyelonephritis. All patients had at least 1 prior episode of clinical pyelonephritis. Data were collected to determine whether acute pyelonephritic changes could be differentiated from chronic pyelonephritis on the basis of MRI characteristics. RESULTS: Of the 9 patients 4 were identified as having acute pyelonephritis on MRI (persistently high signal intensity after gadolinium), 2 demonstrated evidence of postpyelonephritic scar (parenchymal loss without change in signal intensity), 1 had evidence of acute pyelonephritis and chronic changes, and 2 had a completely normal examination (decreased signal intensity after gadolinium). At our institution the billable cost of MRI to the patient is $1,329, while the billable cost of 99mtechnetium DMSA is $1,459. All patients younger than 6 years required intravenous sedation for MRI, whereas 70% of those younger than 6 years require intravenous sedation for DMSA scanning at our institution. MRI provided greater anatomical detail regarding the renal architecture without radiation exposure, and allowed the unambiguous diagnosis of acute versus chronic pyelonephritis scar in a 1-time (versus often multipart for DMSA) imaging study. CONCLUSIONS: In cases where adjunctive imaging studies are useful to make a diagnosis gadolinium enhanced inversion recovery magnetic resonance imaging allows the detection of acute pyelonephritis rapidly, cost-effectively and safely in the pediatric population.     

Is there a role for magnetic resonance imaging in renal trauma?

BACKGROUND: Computed tomography (CT) has been the most informative imaging method in renal trauma. Despite the good sensitivity of magnetic resonance imaging (MRI) to the presence of hematoma, edema and ischemia, MRI has not been widely studied in patients with renal trauma. The present study was initiated to evaluate the role of MRI in patients with renal trauma. METHODS: Between June 1998 and September 1999, CT and MRI were prospectively performed on 12 patients who suffered from renal trauma and the results reviewed. RESULTS: The presence and size of perirenal hematoma could be detected by both CT and MRI. Magnetic resonance imaging could differentiate intrarenal hematoma from perirenal hematoma more accurately, and provided additional information about the hematoma as T1- and T2-weighted MRI were able to determine recent bleeding in the hematoma by regional differences in signal intensity. Magnetic resonance imaging clearly revealed renal fracture with non-viable fragment and detected focal renal laceration that was not detected on CT due to perirenal hematoma associated with renal infarction. However, although MRI had many advantages over CT, it had also major drawbacks, which were that it required longer imaging time and increased the cost. CONCLUSIONS: Magnetic resonance imaging may be useful in renal trauma. However, it is suggested that MRI should be limited to carefully selected patients, such as those with severe renal injury or equivocal findings on CT.     

The Role of Magnetic Resonance Imaging in the Investigation and Management of Invasive Lobular Carcinoma—A 3‐Year Retrospective Study in Two District General Hospitals

Invasive lobular carcinoma (ILC) accounts for 5–15% of breast cancers. In comparison to other types of breast cancer, ILC is more likely to be associated with multifocal and contralateral breast involvement as well as a tendency to a diffuse infiltrative growth pattern which can represent a diagnostic challenge. The National Institute of Clinical Excellence guidelines in 2009 recommended the use of magnetic resonance imaging (MRI) in the preoperative assessment of ILC. This study aims to assess compliance with the guidelines in two District General Hospitals and the utility of MRI in the investigation of ILC. All cases of ILC between 2011 and 2013 were retrospectively identified from the pathology database and their breast imaging findings, pathology report, and operative intervention were reviewed. A total of 126 patients were identified with ILC, of these 46 had MRI preoperatively (36.5%). MRI upgraded mammography/ultrasound diagnoses in 10 patients (21.7%). MRI showed multicentric unilateral disease in 17 patients (37.0%) occult on ultrasound/mammogram, with these patients undergoing mastectomy and 16/17 (94.1%) confirmed multifocality on pathology. MRI showed a contralateral lesion in 9 patients (19.6%), four (8.7%) of which were malignant and had bilateral surgery, and five (10.9%) were benign on further imaging/biopsy. MRI also downgraded three patients (6.5%) to unifocal disease with reported multifocal appearances on mammography/ultrasound, and these patients underwent breast‐conserving surgery. MRI adds significant additional information to mammograms/ultrasound in ILC and should be undertaken in all such cases preoperatively assuming no contraindication.     

Vestibular schwannoma in patients with sudden sensorineural hearing loss

Sudden sensorineural hearing loss (SSNHL) has several etiologies. It may be a presenting symptom of vestibular schwannoma (VS). This study aimed to establish the incidence of VS in patients with SSNHL, and we report several unusual cases among these patients. We reviewed retrospectively the charts and magnetic resonance imaging (MRI) findings of all adult patients who presented with SSNHL between 2002 and 2008. We utilized three-dimensional fast imaging with steady-state acquisition temporal MRI as a screening method. Of the 295 patients with SSNHL, VS was found in 12 (4%). All patients had intrameatal or small to medium-sized tumors. There were three cases with SSNHL in one ear and an incidental finding of intracanalicular VS in the contralateral ear. There were four cases of VS that showed good recovery from SSNHL with corticosteroid treatment. There were two cases that mimicked labyrinthitis with hearing loss and vertigo. A greater number of cases than expected of VS were detected in patients with SSNHL, as a result of increasing widespread use of MRI. Various unusual findings in these patients were identified. MRI would seem to be mandatory in all cases of SSNHL.     

MRI对腰椎间盘突出症的诊断价值

目的 探讨ＭＲＩ对于腰椎间盘突出病理分型的诊断价值。方法 比较２４２例腰椎间盘突出症例的ＭＲＩ检查结果与手术所见。结果 手术证实２４２名患者中包含型椎间盘突出１２９例,非包含型１１３例。轴位ＭＲＩ区分含民非包含型椎间透突出的敏感性、特异性和准确性分别为７７．９％、７２．１％和７４．８％,矢状位为８０．５％、７６．０％和７８．１％。结论 根据ＭＲＩ检查结果区分包含型与非包含型椎间盘突出并不可靠。     

磁共振成像对隆乳材料鉴别及并发症处理的指导意义

目的:分析隆乳材料及术后并发症的MRI表现特点,评估磁共振检查的临床价值。材料和方法:搜集53例经过MRI检查的隆乳术后患者,针对不同的隆乳材料制定合适的扫描序列,分析植入或注射不同类型假体的MRI表现。结果:四种隆胸材料(聚丙烯酰胺水凝胶、硅凝胶、自体脂肪移植、透明质酸)的位置、信号、边界在磁共振图像上有特征性表现,通过扫描序列组合及增强扫描可以准确判断隆胸材料的性质及并发症情况,动态增强扫描还可以发现腺体病变。结论:MRI是鉴别乳腺假体类型及指导术后并发症处理的较好方法。     

Preoperative nomograms incorporating magnetic resonance imaging and spectroscopy for prediction of insignificant prostate cancer

Study Type – Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Nomograms are available that combine clinical and biopsy findings to predict the probability of pathologically insignificant prostate cancer in patients with clinically low‐risk disease. Based on data from patients with Gleason score 6, clinical stage ≤ T2a and PSA <20 ng/ml, our group developed the first nomogram models for predicting insignificant prostate cancer that incorporated clinical data, detailed biopsy data and findings from MRI or MRI/MRSI (BJU Int. 2007;99(4):786–93). When tested retrospectively, these MR models performed significantly better than standard clinical models with and without detailed biopsy data. We prospectively validated the previously published MR‐based nomogram models in a population of patients with Gleason score 6, clinical stage ≤ T2a and PSA <10 ng/ml. Based on data from this same population, we also developed two new models for predicting insignificant prostate cancer that combine MR findings and clinical data without detailed biopsy data. Upon initial testing, the new MR models performed significantly better than a clinical model lacking detailed biopsy data.

OBJECTIVES

• ? To validate previously published nomograms for predicting insignificant prostate cancer (PCa) that incorporate clinical data, percentage of biopsy cores positive (%BC+) and magnetic resonance imaging (MRI) or MRI/MR spectroscopic imaging (MRSI) results.
• ? We also designed new nomogram models incorporating magnetic resonance results and clinical data without detailed biopsy data. Nomograms for predicting insignificant PCa can help physicians counsel patients with clinically low‐risk disease who are choosing between active surveillance and definitive therapy.

PATIENTS AND METHODS

• ? In total, 181 low‐risk PCa patients (clinical stage T1c–T2a, prostate‐specific antigen level <10 ng/mL, biopsy Gleason score of 6) had MRI/MRSI before surgery.
• ? For MRI and MRI/MRSI, the probability of insignificant PCa was recorded prospectively and independently by two radiologists on a scale from 0 (definitely insignificant) to 3 (definitely significant PCa).
• ? Insignificant PCa was defined on surgical pathology.
• ? There were four models incorporating MRI or MRI/MRSI and clinical data with and without %BC+ that were compared with a base clinical model without %BC and a more comprehensive clinical model with %BC+. Prediction accuracy was assessed using areas under receiver–operator characteristic curves.

RESULTS

• ? At pathology, 27% of patients had insignificant PCa, and the Gleason score was upgraded in 56.4% of patients.
• ? For both readers, all magnetic resonance models performed significantly better than the base clinical model (P ≤ 0.05 for all) and similarly to the more comprehensive clinical model.

CONCLUSIONS

• ? Existing models incorporating magnetic resonance data, clinical data and %BC+ for predicting the probability of insignificant PCa were validated.
• ? All MR‐inclusive models performed significantly better than the base clinical model.

     

Changes of the sacrum in severe spondylolisthesis: a possible key pathology of the disorder

Deficient development of the posterior lumbosacral portion has been thought to be a possible etiology of severe spondylolisthesis. However, the precise causes of the deformity have yet to be revealed. To our knowledge, progression of the disorder has not been discussed in the light of sacral changes on magnetic resonance imaging (MRI). The objectives of the present study were to document changes of the sacrum on MRI scans in patients with severe spondylolisthesis and to discuss the relation of these changes to the progression of deformities. Roentgenograms and MRI scans of 13 patients (10 women and 3 men) with severe spondylolisthesis were retrospectively reviewed. Average age at first MRI examination was 20 years (range, 12 to 50 years). The MRI scans commonly showed a defect at the antero-superior portion of the sacrum. This lesion seems to appear during the period of progression of slipping associated with lumbosacral kyphosis. The defect of the sacrum was considered a unique feature to discriminate this type of olisthesis from others. Taking into conside-ration the present results, the deformity can be called kyphospondylolisthesis. Received for publication on Feb. 9, 1999; accepted on June 21, 1999     

Magnetic Resonance Imaging of Adhesive Capsulitis: Correlation with Clinical Staging

The purpose of this study was to evaluate non-contrast magnetic resonance imaging (MRI) findings of adhesive capsulitis and correlate them with clinical stages of adhesive capsulitis. This will hopefully define a role for shoulder MR imaging in the diagnosis of adhesive capsulitis as well as in potentially directing appropriate treatment. Forty-seven consecutive non-contrast magnetic resonance imaging examinations of 46 patients with a clinical diagnosis of adhesive capsulitis were retrospectively reviewed and correlated with clinical staging. Specific MRI criteria correlated with the clinical stage of adhesive capsulitis, including the thickness and signal intensity of the joint capsule and synovium as well as the presence and severity of scarring in the rotator interval. Routine MRI of the shoulder without intraarticular administration of gadolinium can be used to diagnose all stages of adhesive capsulitis, including stage 1, where findings may be subtle on clinical examination. We believe that future studies assessing the role of MRI in guiding the initiation of appropriate treatment should be undertaken.