MR Evaluation of Dural Ectasia in Marfan Syndrome: Reassessment of the Established Criteria in Children, Adolescents, and Young Adults

MRI-Derived Dural Sac and Lumbar Vertebrae 3D Volumetry Has Potential for Detection of Marfan Syndrome

PURPOSE

To assess the feasibility and diagnostic accuracy of MRI-derived 3D volumetry of lower lumbar vertebrae and dural sac segments using shape-based machine learning for the detection of Marfan syndrome (MFS) compared with dural sac diameter ratios (the current clinical standard).

MATERIALS AND METHODS

The final study sample was 144 patients being evaluated for MFS from 01/2012 to 12/2016, of whom 81 were non-MFS patients (46 [67%] female, 36 ± 16 years) and 63 were MFS patients (36 [57%] female, 35 ± 11 years) according to the 2010 Revised Ghent Nosology. All patients underwent 1.5T MRI with isotropic 1 × 1 × 1 mm3 3D T2-weighted acquisition of the lumbosacral spine. Segmentation and quantification of vertebral bodies L3-L5 and dural sac segments L3-S1 were performed using a shape-based machine learning algorithm. For comparison with the current clinical standard, anteroposterior diameters of vertebral bodies and dural sac were measured. Ratios between dural sac volume/diameter at the respective level and vertebral body volume/diameter were calculated.

RESULTS

Three-dimensional volumetry revealed larger dural sac volumes (p < 0.001) and volume ratios (p < 0.001) at L3-S1 levels in MFS patients compared with non-MFS patients. For the detection of MFS, 3D volumetry achieved higher AUCs at L3-S1 levels (0.743, 0.752, 0.808, and 0.824) compared with dural sac diameter ratios (0.673, 0.707, 0.791, and 0.848); a significant difference was observed only for L3 (p < 0.001).

CONCLUSION

MRI-derived 3D volumetry of the lumbosacral dural sac and vertebral bodies is a feasible method for quantifying dural ectasia using shape-based machine learning. Non-inferior diagnostic accuracy was observed compared with dural sac diameter ratio (the current clinical standard for MFS detection).

Surgical Evaluation and Management of Spinal Pathology in Patients with Connective Tissue Disorders

Connective tissue disorders represent a varied spectrum of syndromes that have important implications for the spine deformity surgeon. Spine surgeons must be aware of these diverse and global manifestations of disease because they have significant impact on perioperative and postoperative outcomes.

Phenotyping spinal abnormalities in patients with Neurofibromatosis type 1 using whole-body MRI

Neurofibromatosis Type 1 (NF1) has been reported to be associated with a variety of spinal abnormalities. The purpose of this study was to quantify the prevalence of spinal abnormalities in a collective of NF1 patients that is representative for the general NF1 population, to associate the co-appearance of spinal abnormalities with both NF1 and clinical symptoms and to investigate if different mutations of the NF1 gene affect the prevalence of these abnormalities. Retrospectively, 275 patients with NF1 and an age- and sex-matched collective of 262 patients were analyzed. The prevalence of spinal abnormalities was recorded. Mutational analysis of the NF1 gene was obtained in 235 NF1 patients. Associations between spinal abnormalities, clinical symptoms and genotype were investigated by binary logistic regression analysis. Prevalence of all spinal abnormalities was higher in NF1 patients than in the control group. Six characteristics of spinal abnormalities were significantly associated with NF1 (all p < 0.05). An influence of scalloping on scoliosis (OR 3.01; p = 0.002); of meningoceles (OR 7.63) and neuroforaminal tumors (OR 2.96) on scalloping, and of dural ectasia on neuroforaminal tumors (OR 1.93) was identified. Backpain and loss of motor function were associated with neuroforaminal tumors, spinal tumors and scalloping of vertebral bodies (all p < 0.05). Specific mutations of the NF1 gene were not relevantly associated with the development of spinal abnormalities. These findings can aid clinicians to improve clinical care of NF1 patients by creating awareness for co-appearences of specific spinal abnormalities and associated symptoms.

A Tale of Two Organ Systems: Imaging Review of Diseases Affecting the Thoracic and Neurological Systems. Part 2

In an era of rapidly expanding knowledge and sub-specialization, it is becoming increasingly common to focus on one organ system. However, the human body is intimately linked, and disease processes affecting one region of the body not uncommonly affect the other organ systems as well. Understanding diseases from a macroscopic perspective, rather than a narrow vantage point, enables efficient and accurate diagnosis. This tenet holds true for diseases affecting both the thoracic and neurologic systems; in isolation, the radiologic appearance of disease in one organ system may be nonspecific, but viewing the pathophysiologic process in both organ systems may markedly narrow the differential considerations, and potentially lead to a definitive diagnosis. In this article, we discuss a variety of disease entities known to affect both the thoracic and neurological systems, either manifesting simultaneously or at different periods of time. Some of these conditions may show neither thoracic nor neurological manifestations. These diseases have been systematically classified into infectious, immune-mediated/ inflammatory, vascular, syndromic/ hereditary and neoplastic disorders. The underlying pathophysiological mechanisms linking both regions and radiologic appearances in both organ systems are discussed. When appropriate, brief clinical and diagnostic information is provided. Ultimately, accurate diagnosis will lead to expedited triage and prompt institution of potentially life-saving treatment for these groups of complex disorders.

A scoping review presenting a wide variety of research on paediatric and adolescent patients with Marfan syndrome

Aim

The present study aimed to map and summarise the research on children, aged 0‐18 years, with Marfan syndrome, identify research gaps and point to research agendas.

Methods

A scoping review was systematically performed by searching multiple databases from January 1996 to April 2019. Primary studies presenting results on at least six individuals aged 0‐18 years with Marfan syndrome, diagnosed according to the Ghent nosology, were selected.

Results

From 2341 de‐duplicated records, 92 papers were included, mapped and described. Their topics were diagnostics (12%), cardiovascular matters (50%), skeletal matters (22%), ocular matters (9%), other medical aspects (5%) and psychosocial perspectives (2%). Most studies were from Europe and North America and published between 1999 and 2019 in subject‐specific or paediatric journals, while a few were published in genetics journals. All studies had quantitative designs, and very few were multicentre studies. Each study had six to 608 subjects for a total of approximately 5809.

Conclusion

A wide range of research topics on adolescent and paediatric Marfan syndrome was found, but qualitative studies and a focus on psychosocial matters were lacking. Future investigations addressing noncardiovascular consequences and patient experiences are needed, as well as studies reaffirming or replicating existing intervention study results.

Dural ectasia in Marfan syndrome and other hereditary connective tissue disorders: a 10-year follow-up study

BACKGROUND CONTEXT

Dural ectasia is widening of the dural sac often seen in patients with Marfan syndrome and other hereditary connective tissue disorders. Dural ectasia can cause specific symptoms and is associated with surgical complications. The knowledge on how and at which age dural ectasia develops is incomplete. There is no established gold standard for diagnosing dural ectasia, making it difficult to compare results from different studies.

PURPOSE

Our primary aim was to explore whether the radiological findings of dural ectasia changed after 10 years in an adult cohort with suspected Marfan syndrome. Our secondary aim was to re-evaluate the radiological criteria of dural ectasia.

STUDY DESIGN

Prospective cohort study.

PATIENT SAMPLE

Sixty-two persons from a cross-sectional study of 105 persons with suspected Marfan syndrome were included in a 10-year follow-up of dural ectasia. Forty-six were diagnosed with Marfan syndrome, 7 with Loeys-Dietz syndrome, and 5 with other hereditary connective tissue disorders. For comparison 64 matched hospital controls were evaluated.

OUTCOME MEASURES

Previously used radiological criteria for dural ectasia based on quantitative measurements of the lumbosacral spine.

METHODS

MRI of the lumbosacral spine was performed if not contraindicated, and if so then CT was performed. Differences in the study group between baseline and follow-up were assessed with paired Student t test, Wilcoxon rank signed test, and McNemar test. Receiver operating characteristic curves were constructed to assess the ability of radiological measurement to differentiate between the study and control group.

RESULTS

Fifty-two of 58 patients with hereditary connective tissue disorders and 11 controls had dural ectasia at follow-up. Forty-five Marfan patients had dural ectasia at follow-up vs. 41 at baseline. Five Loeys-Dietz patients had dural ectasia at follow-up vs. four at baseline. Twenty-four Marfan and 2 Loeys-Dietz patients had anterior sacral meningocele at follow-up, compared with 21 and 1, respectively, at baseline. Three Marfan patients developed herniation of a nerve root sleeve during follow-up. This was not seen in other individuals. The dural sac ended significantly lower at follow-up, and the dural sac ratio at level L5 was significantly increased from baseline in the Marfan patients.

CONCLUSIONS

In Marfan and Loeys-Dietz syndrome, dural ectasia may present or worsen during adulthood. The cut-off value of dural sac ratio at level S1 is suggested elevated to 0.64. The results from the present study may help as guidance for appropriate follow-up of patients with dural ectasia.

Assessment of Dural Ectasia Using Computed Tomodensitometry as a Criterion in Marfan Syndrome

OBJECTIVE

The aim of this study was to reevaluate dural ectasia criteria in Marfan syndrome patients fulfilling the revised Ghent criteria.

METHODS

Lumbar computed tomography scans of 19 Marfan patients and 30 matched control subjects were retrospectively assessed. Dural sac ratio (DSR), nerve root sleeve diameter, pedicle width, and a scalloping or meningocele presence were each assessed by 2 readers blinded from the diagnosis. Mann-Whitney-Wilcoxon tests compared the patient and control groups. Receiver operating characteristic curve analysis and multivariate models determined the optimal cutoff value.

RESULTS

A DSR value greater than 0.69 at L5 (DSR-L5) such as L4 scalloping of more than 2.65 mm (scall-L4) and 6 or more vertebrae showing a scalloping of more than 3 mm (6-scall) were found very specific but with limited sensitivity. Multivariate model combining DSR-L5 + scall-L4 showed good positive predictive value, whereas model combining DSR-L5 + 6-scall showed good negative predictive value.

CONCLUSIONS

Assessment of DSR and vertebral scalloping allows valuable depiction of dural ectasia in Marfan syndrome patients.

Epidural analgesia complicated by dural ectasia in the Marfan syndrome

Patients with the Marfan syndrome are considered to be high risk during pregnancy and warrant a complete multidisciplinary evaluation. One goal is to minimize hemodynamic fluctuations during labor since hypertensive episodes may result in aortic dissection or rupture. Although they may prevent these complications, neuraxial techniques may be complicated by dural ectasia. The case of a parturient with the Marfan syndrome and mild dural ectasia is presented. During attempted labor epidural placement, unintentional dural puncture occurred. A spinal catheter was used for adequate labor analgesia, and a resultant postdural puncture headache was alleviated by an epidural blood patch under fluoroscopic guidance.

Sagittal Normal Limits of Lumbosacral Spine in a Large Adult Population: A Quantitative Magnetic Resonance Imaging Analysis

OBJECTIVES

The objective of this study was to determine, using magnetic resonance imaging (MRI) of the lumbosacral spine from L1 to S1, the values of the normal sagittal diameter of the spinal canal (SCD), sagittal diameter of the dural sac (DSD), and the normal values of dural sac ratio (DSR) in a large nonsymptomatic adult population and to discriminate whether a vertebral canal is pathological or nonpathological for dural ectasia and/or stenosis.

MATERIALS AND METHODS

Six hundred and four patients were prospectively enrolled. All measurements were performed on MRI sagittal T1- and T2-weighted images. The 95% confidence interval (95% CI), defined as mean ± 1.96 standard deviation, was determined for each metric. The upper limit of 95% CI was considered the cutoff value for the normal DSR; the lower limit of 95% CI was considered the cutoff value for the normal SCD.

RESULTS

SCD cutoff values from L1 to S1 ranged from 14.5-10.1 mm (males) to 15.0-9.9 mm (females). DSD ratios at S1 and L4 level show a significant difference in male and female groups: 11% of S1/L4 values exceeded 1 in male group while only 4% of S1/L4 values exceeded 1 in female group. Mean DSR at each level was significantly higher in female patients than in male patients (P < 0.001), ranging from 0.70 to 0.56 (male) and from 0.82 to 0.63 (female).

CONCLUSIONS

We determined the cutoff values for the normal DSR and for the normal SCD. Our findings show the relevant discrepancies with respect to literature data for diagnosis of lumbar stenosis and/or dural ectasia.

The main pulmonary artery in adults: a controlled multicenter study with assessment of echocardiographic reference values, and the frequency of dilatation and aneurysm in Marfan syndrome

BACKGROUND

Echocardiographic upper normal limits of both main pulmonary artery (MPA) diameters (MPA-d) and ratio of MPA to aortic root diameter (MPA-r) are not defined in healthy adults. Accordingly, frequency of MPA dilatation based on echocardiography remains to be assessed in adults with Marfan syndrome (MFS).

METHODS

We enrolled 123 normal adults (72 men, 52 women aged 42 ± 14 years) and 98 patients with MFS (42 men, 56 women aged 39 ± 14 years) in a retrospective cross-sectional observational controlled study in four tertiary care centers. We defined outcome measures including upper normal limits of MPA-d and MPA-r as 95 quantile of normal persons, MPA dilatation as diameters > upper normal limits, MPA aneurysm as diameters >4 cm, and indication for surgery as MPA diameters >6 cm.

RESULTS

MPA diameters revealed normal distribution without correlation to age, sex, body weight, body height, body mass index and body surface area. The upper normal limit was 2.6 cm (95% confidence interval (CI) =2.44-2.76 cm) for MPA-d, and 1.05 (95% CI = .86-1.24) for MPA-r. MPA dilatation presented in 6 normal persons (4.9%) and in 68 MFS patients (69.4%; P < .001), MPA aneurysm presented only in MFS (15 patients; 15.3%; P < .001), and no patient required surgery. Mean MPA-r were increased in MFS (P < .001), but ratios >1.05 were equally frequent in 7 normal persons (5%) and in 8 MFS patients (10.5%; P = .161). MPA-r related to aortic root diameters (P = .042), reduced left ventricular ejection fraction (P = .006), and increased pulmonary artery systolic pressures (P = .040). No clinical manifestations of MFS and no FBN1 mutation characteristics related to MPA diameters.

CONCLUSIONS

We established 2.6 cm for MPA-d and 1.05 for MPA-r as upper normal limits. MFS exhibits a high prevalence of MPA dilatation and aneurysm. However, patients may require MPA surgery only in scarce circumstances, most likely because formation of marked MPA aneurysm may require LV dysfunction and increased PASP.

Standardization and validation of a novel and simple method to assess lumbar dural sac size

AIM

To develop and validate a simple, reproducible method to assess dural sac size using standard imaging technology.

MATERIALS AND METHODS

This study was institutional review board-approved. Two readers, blinded to the diagnoses, measured anterior–posterior (AP) and transverse (TR) dural sac diameter (DSD), and AP vertebral body diameter (VBD) of the lumbar vertebrae using MRI images from 53 control patients with pre-existing MRI examinations, 19 prospectively MRI-imaged healthy controls, and 24 patients with Marfan syndrome with prior MRI or CT lumbar spine imaging. Statistical analysis utilized linear and logistic regression, Pearson correlation, and receiver operating characteristic (ROC) curves.

RESULTS

AP-DSD and TR-DSD measurements were reproducible between two readers (r = 0.91 and 0.87, respectively). DSD (L1–L5) was not different between male and female controls in the AP or TR plane (p = 0.43; p = 0.40, respectively), and did not vary by age (p = 0.62; p = 0.25) or height (p = 0.64; p = 0.32). AP-VBD was greater in males versus females (p = 1.5 × 10⁻⁸), resulting in a smaller dural sac ratio (DSR) (DSD/VBD) in males (p = 5.8 × 10⁻⁶). Marfan patients had larger AP-DSDs and TR-DSDs than controls (p = 5.9 × 10⁻⁹; p = 6.5 × 10⁻⁹, respectively). Compared to DSR, AP-DSD and TR-DSD better discriminate Marfan from control subjects based on area under the curve (AUC) values from unadjusted ROCs (AP-DSD p < 0.01; TR-DSD p = 0.04).

CONCLUSION

Individual vertebrae and L1–L5 (average) AP-DSD and TR-DSD measurements are simple, reliable, and reproducible for quantitating dural sac size without needing to control for gender, age, or height.

Dural ectasia

Dural ectasia is one of the likely causes of incomplete or failed spinal anaesthesia. Its association with diseases like Marfans syndrome, neurofibromatosis, osteogenesis imperfecta, vertebral fracture, postopertative adhesions, trauma etc., is often overlooked as a reason for inadequate spinal anaesthesia. Greater than normal volume of cerebrospinal fluid in the lumber theca in dural ectasia is postulated to restrict the spread of intrathecally injected Local anaesthetic. Here, we report a case of failed spinal anaesthesia but successful epidural anaesthesia in later setting in a patient with dural ectasia.

Spinal imaging features in Japanese patients with Marfan syndrome: a case-control study

PURPOSE

The purpose of our study was to evaluate the morphology of the lumbosacral spine, i.e. the dura and vertebral body shape, of Japanese patients with Marfan syndrome (MFS) by comparing it with sex- and age-matched controls.

MATERIALS AND METHODS

Spinal MR or CT images of 32 MFS patients and 32 controls were retrospectively reviewed. The anteroposterior dural sac diameter (DSD), anteroposterior vertebral body diameter (VBD), and vertebral body height (VBH) were measured from L1 to S1 levels and the dural sac ratio [DSR = (DSD/VBD)] and vertebral body aspect ratio [VAR = (VBH/VBD)] were calculated.

RESULTS

At each level, mean DSD and DSR were significantly higher in MFS patients; VBD was not. The cutoff values for DSR to differentiate between MFS patients and the controls were 0.59, 0.46, 0.42, 0.45, 0.47, and 0.47 from the level of L1 to S1. At a sensitivity of 93.8 % and a specificity of 84.4 % the cutoff value at S1 was most diagnostic. In MFS patients VAR was significantly higher at L3 and L4.

CONCLUSION

Our cutoff value for DSR >0.47 at S1 may help to identify MFS in the Japanese population. A square-like appearance of the L3 and L4 vertebral bodies is a supplementary finding in MFS patients.

Noninvasive diagnosis and management of spontaneous intracranial hypotension in patients with marfan syndrome: Case Report and Review of the Literature

Background:

Spontaneous intracranial hypotension is an uncommon clinical entity. Heritable connective tissue disorders (HCTD), such as Marfan syndrome, are frequently implicated as an underlying cause, due to dural structural weaknesses that predispose patients to spontaneous cerebrospinal fluid (CSF) leak. Due to the high prevalence of multi-system disease in HCTD, diagnosis and treatment are often complicated.

Case Description:

We present a 58-year-old female with Marfan syndrome on anticoagulation for a mechanical aortic valve replacement who came to medical attention with severe, acute-onset headache following a straining episode. Noninvasive magnetic resonance (MR) myelography confirmed thoracic CSF extravasations and multiple lumbar diverticula. The patient was treated conservatively and her symptoms resolved.

Conclusion:

We discuss the common presentation, diagnostic tools, and treatment options for spontaneous CSF leaks in patients with Marfan syndrome or related HCTD with an emphasis on noninvasive modalities and a review of the major radiographic criteria used to diagnose dural abnormalities, such as dural ectasia.

Dural ectasia in Loeys-Dietz syndrome: comprehensive study of 30 patients with a TGFBR1 or TGFBR2 mutation

The purpose of this study was to assess the frequency, severity, and clinical associations of dural ectasia (DE) in Loeys-Dietz syndrome (LDS). Database analysis of three German metropolitan regions identified 30 patients with LDS and TGFBR1 mutation in 6 and a TGFBR2 mutation in 24 individuals (17 men; mean age: 31 ± 19 years), as well as 60 age and sex-matched control patients with Marfan syndrome carrying a FBN1 mutation. DE was present in 22 patients with LDS (73%), and it related to skeletal score points (p = 0.008), non-skeletal score points (p < 0.001), and to the presence of ≥7 systemic score points (p = 0.010). Similarly, the severity of DE was related to body height (p = 0.010) and non-skeletal score points (p = 0.004). Frequency (p = 0.131) and severity of DE (p = 0.567) was similar in LDS and Marfan syndrome. DE is a manifestation of LDS that occurs with similar frequency and severity as in Marfan syndrome. Severity of DE may serve as a marker of the overall connective tissue disease severity. LDS may be considered in patients with DE.

Prevalence of dural ectasia in Loeys-Dietz syndrome: comparison with Marfan syndrome and normal controls

BACKGROUND AND PURPOSE

Dural ectasia is well recognized in Marfan syndrome (MFS) as one of the major diagnostic criteria, but the exact prevalence of dural ectasia is still unknown in Loeys-Dietz syndrome (LDS), which is a recently discovered connective tissue disease. In this study, we evaluated the prevalence of dural ectasia in LDS according by using qualitative and quantitative methods and compared our findings with those for with MFS and normal controls.

MATERIAL AND METHODS

We retrospectively studied 10 LDS (6 males, 4 females, mean age 36.3 years) and 20 MFS cases (12 males, 8 females, mean age 37.1 years) and 20 controls (12 males, 8 females, mean age 36.1 years) both qualitatively and quantitatively using axial CT images and sagittal multi-planar reconstruction images of the lumbosacral region. For quantitative examination, we adopted two methods: method-1 (anteroposterior dural diameter of S1> L4) and method-2 (ratio of anteroposterior dural diameter/vertebral body diameter>cutoff values). The prevalence of dural ectasia among groups was compared by using Fisher's exact test and the Tukey-Kramer test.

RESULTS

In LDS patients, the qualitative method showed 40% of dural ectasia, the quantitative method-1 50%, and the method-2 70%. In MFS patients, the corresponding prevalences were 50%, 75%, and 85%, and in controls, 0%, 0%, and 5%. Both LDS and MFS had a significantly wider dura than controls.

CONCLUSIONS

While the prevalence of dural ectasia varied depending on differences in qualitative and quantitative methods, LDS as well as MFS, showed, regardless of method, a higher prevalence of dural ectasia than controls. This finding should help the differentiation of LDS from controls.

Comprehensive analysis of dural ectasia in 150 patients with a causative FBN1 mutation

The purpose of this study was to perform a comprehensive study of dural ectasia (DE) related to FBN1 mutations. We performed a database analysis of two German metropolitan regions of 150 patients (68 men, 82 women; mean age 35 ± 16 years). All patients had a FBN1 mutation and underwent dural magnetic resonance imaging. Age was <16 years in 20, 16-25 in 27, 26-35 in 67, and >35 in 36 patients. Prevalence of dural ectasia was 89% with criteria of Oosterhof and Habermann, 83% with Fattori, 78% with Lundby, and 59% with Ahn. DE was less frequent in patients <16 years with Ahn and Fattori. DE related to skeletal manifestations with all criteria, to aortic Z-scores and mitral valve prolapse with criteria of Habermann and Lundby, and to age with criteria of Fattori. The Fattori-grade of DE increased with age, aortic Z-scores, and skeletal score points. There was no consistent relationship of DE with any type of FBN1 mutation. DE is frequent in patients with FBN1 mutations irrespective of age and its severity increases during life. Criteria of Oosterhof and Habermann yielded most consistent diagnostic results. DE relates to skeletal involvement, aortic Z-scores, and mitral valve prolapse.

Cardiovascular magnetic resonance in Marfan syndrome

This review provides an overview of Marfan syndrome with an emphasis on cardiovascular complications and cardiovascular imaging. Both pre- and post-operative imaging is addressed with an explanation of surgical management. All relevant imaging modalities are discussed with a particular focus on cardiovascular MR.

The Kid-Short Marfan Score (Kid-SMS) - an easy executable risk score for suspected paediatric patients with Marfan syndrome

AIM

Due to age-dependent manifestations, diagnosis of Marfan syndrome (MFS) in children and adolescents is sophisticated. Although revised Ghent criteria is a major step forward, its utility in children is still restricted due to expensive and technically advanced diagnostics. As early diagnosis submits long-term benefits concerning prognosis, the need of an appropriate diagnostic tool for risk stratification of suspected paediatric patients with Marfan is justified.

METHODS AND RESULTS

Sixty paediatric patients with Marfan were subject to a standardized diagnostic programme. All clinical symptoms of the revised Ghent nosology were analysed concerning age at first clinical manifestation, prevalence and likelihood ratio for MFS. Symptoms with early onset, high prevalence and high positive likelihood ratio were identified and combined for a risk score called Kid-Short Marfan Score (Kid-SMS). Three risk categories for suspicion of Marfan syndrome were developed. Finally, the Kid-SMS was operated in 130 paediatric patients with suspected MFS. Kid-SMS identified significantly more suspected patients with Marfan compared with Ghent nosology, revised Ghent and genetics alone without oversensitivity.

CONCLUSION

Whereas diagnosis of MFS in childhood is sophisticated, Kid-SMS is a useful tool for risk stratification of suspected paediatric patients with Marfan by easy executable diagnostics, especially for paediatricians and paediatric cardiologists.

Anterior dural ectasia mimicking a lytic lesion in the posterior vertebral body in ankylosing spondylitis

Anterior dural ectasia is an extremely rare finding in ankylosing spondylitis (AS). The authors describe a unique case of AS in which the patient presented with cauda equina syndrome as well as an unusual imaging finding of erosion of the posterior aspect of the L-1 (predominantly) and L-2 vertebral bodies due to anterior dural ectasia. Symptomatic patients with long-standing AS should be monitored for the presence of dural ectasia, which can be anterior in location, as is demonstrated in the present case.

Dural ectasia in individuals with Marfan-like features but exclusion of mutations in the genes FBN1, TGFBR1 and TGFBR2

Mutations in the genes FBN1, TGFBR1, and TGFBR2 can result in heritable connective tissue disorders comprising the Marfan syndrome and the Loeys-Dietz syndrome. Dural ectasia is a characteristic manifestation of both syndromes. However, dural ectasia has not yet been investigated in connective tissue disorders that are unrelated to mutations in the FBN1, TGFBR1 or TGFBR2 genes. Here, we assessed dural ectasia in 33 individuals both with typical manifestations of heritable connective tissue disease and in whom mutations in all three genes had been excluded. We identified 19 individuals with dural ectasia (58%), who exhibited major skeletal manifestations of the Marfan syndrome more frequently than the remaining 14 persons without dural ectasia (p = 0.06). Moreover, only persons with dural ectasia fulfilled clinical criteria of the Marfan syndrome (p = 0.01). Conversely, aortic aneurysm (12 patients; p = 0.8), aortic dissection (five patients; p = 0.1), spontaneous dissection of the carotid arteries (five patients; p = 1), and mitral valve prolapse (13 patients; p = 0.4) were similarly frequent irrespective of dural ectasia. We conclude that dural ectasia is a marker for connective tissue disease which coincides with skeletal rather than with cardiovascular manifestations, and which may involve currently uncharacterized pathogenetic mechanisms and syndromes.

Predictors of outcome of mitral valve prolapse in patients with the Marfan syndrome

Mitral valve prolapse has a prevalence of 2% to 3% in the general population, with adverse outcomes such as mitral valve regurgitation (MVR), heart failure, and endocarditis. Predictors of outcomes are used in idiopathic mitral valve prolapse for the timing of surgery, but such predictors are unknown in Marfan syndrome. Therefore, a population-based cohort study of 112 patients (49 male, 63 female; mean age 34 ± 15 years) with classic Marfan syndrome and mitral valve prolapse with moderate or less MVR at baseline was conducted. During 4.6 ± 3.6 years of follow-up, progression of MVR was observed in 41 patients and valve-related events, which comprised mitral valve endocarditis (7 events), heart failure (5 events), and mitral valve surgery (25 events), were observed in 31 patients. Multivariate Cox proportional-hazards regression analysis identified a flail mitral leaflet (hazard ratio [HR] 3.262, 95% confidence interval [CI] 1.406 to 7.566, p = 0.006) and increased indexed end-systolic left ventricular diameters (HR 1.113, 95% CI 1.043 to 1.188, p = 0.001) as independent predictors of progression of MVR. Similarly, mitral valve-related events were independently predicted by a flail mitral leaflet (HR 5.343, 95% CI 2.229 to 12.808, p <0.001), and mild (HR 14.336, 95% CI 1.873 to 109.755, p = 0.01) or moderate (HR 16.849, 95% CI 2.205 to 128.76, p = 0.006) degree of MVR. Conversely, aortic dilatation, dural ectasia, and sporadic mode of inheritance were not associated with outcome. In conclusion, the same clinical determinants that predict outcomes in idiopathic mitral valve prolapse also predict outcomes in mitral valve prolapse associated with Marfan syndrome.

Frequency and age-related course of mitral valve dysfunction in the Marfan syndrome

Mitral valve (MV) prolapse (MVP) has a high prevalence of 2% to 3% in the general population and thus constitutes the most common cause of severe nonischemic MV regurgitation (MVR). MVP is also common in persons with the Marfan syndrome. However, to date, a large-scale population-based cohort study using modern echocardiographic techniques has not been performed, and the frequency of MVP and the relation of MV dysfunction and age have not been investigated. Therefore, we conducted a population-based cohort study of 204 patients (108 males and 96 females, aged 31.2 ± 16.4 years) with classic Marfan syndrome. We performed echocardiographic follow-up of 174 patients for a mean of 4.4 ± 4.3 years. On the initial or subsequent echocardiographic scan, MVP was present in 82 patients (40%), severe MVR in 25 (12%), and MV endocarditis in 5 patients (2.5%). At 30 years of age, the Weibull cumulative distribution was 42.6% (95% confidence interval [CI] 36% to 50%) for MVP, 56.5% (95% CI 49.3% to 64%) for MVR of any degree, 6.7% (95% CI 3.9% to 11.3%) for severe MVR, and 0.92% (95% CI 0.21% to 3.91%) for MV endocarditis. The cumulative hazard for severe MVR and MV endocarditis was estimated to increase with age. MVP was associated with dural ectasia (p = 0.01), ectopia lentis (p = 0.02), and skeletal involvement (p <0.001). Severe MVR was related to tricuspid valve prolapse (p = 0.002) and to the sporadic form of the Marfan syndrome (p = 0.006). In conclusion, MVP was comparatively frequent in patients with the Marfan syndrome and carries an increased risk of progression to severe MVR and endocarditis, especially in older adults.

Spinal imaging contributes to the diagnosis of Marfan syndrome

The diagnosis of Marfan syndrome (MFS) is defined by a combination of major and minor criteria, related to the different systems involved, according to the Ghent nosology of the spine. Spinal imaging can detect both skeletal (including scoliosis and spondylolisthesis) and neurological involvement (i.e. dural ectasia). The aim of the present study was to assess the interest of screening the rachis by conventional radiography CR and complementary imaging (computed tomography [CT] or magnetic resonance imaging [MRI]) in patients suspected of MFS, and to modelise the most relevant imaging procedure to diagnose MFS.

METHODS

Evaluation of the sensitivity and specificity of CR of the lumbosacral spine versus sectional imaging for the detection of dural ectasia (DE) in a subgroup of 92 patients suspected of MFS. Retrospective analysis of the contribution of CR to the diagnosis of MFS in 1992 patients referred to our clinic.

RESULTS

DE was detected by CR in 12 of the 92 patients (13%) and was always confirmed by CT or MRI. Complementary imaging alone detected 33 DE (35.9%). All patients with DE detected by CR were diagnosed with MFS. Among the 1992 patients, 591 were confirmed MFS; 117 patients had DE detected by CR (19,8%) while 12 (2,0%) were detected by complementary imaging. In MFS patients, 98 (16.6%) had significant scoliosis and 14 (2.4%) had spondylolisthesis. The positive predictive value of DE detected by CR for the diagnosis of MFS was 92.9% (95% IC: 86.8-96.4), and the negative predictive value was 74.6% (95% IC: 72.6-76.5). We conclude that spinal imaging is useful for the diagnosis of MFS.

Marfan syndrome. Part 1: pathophysiology and diagnosis

Marfan syndrome is a connective-tissue disease inherited in an autosomal dominant manner and caused mainly by mutations in the gene FBN1. This gene encodes fibrillin-1, a glycoprotein that is the main constituent of the microfibrils of the extracellular matrix. Most mutations are unique and affect a single amino acid of the protein. Reduced or abnormal fibrillin-1 leads to tissue weakness, increased transforming growth factor beta signaling, loss of cell-matrix interactions, and, finally, to the different phenotypic manifestations of Marfan syndrome. Since the description of FBN1 as the gene affected in patients with this disorder, great advances have been made in the understanding of its pathogenesis. The development of several mouse models has also been crucial to our increased understanding of this disease, which is likely to change the treatment and the prognosis of patients in the coming years. Among the many different clinical manifestations of Marfan syndrome, cardiovascular involvement deserves special consideration, owing to its impact on prognosis. However, the diagnosis of patients with Marfan syndrome should be made according to Ghent criteria and requires a comprehensive clinical assessment of multiple organ systems. Genetic testing can be useful in the diagnosis of selected cases.

Dural ectasia in Marfan syndrome: a case control study

BACKGROUND AND PURPOSE

Dural ectasia (DE) is one of the major criteria of Marfan syndrome (MFS). Our aim was to establish the prevalence of DE in an adult population fulfilling the Ghent criteria for MFS and to assess definitions of DE.

MATERIALS AND METHODS

One hundred five adults with suspected MFS were included. MR imaging at 1.5T was performed unless contraindicated; then CT was obtained. Lumbosacral anteroposterior vertebral body diameters (VBD) and dural sac diameters (DSD) were measured. Dural sac ratios (DSR = DSD/VBD) at levels L3 through S1 were calculated. Anterior meningoceles, herniations of nerve root sleeves, and scalloping were characterized. One hundred one sex- and age-matched patients were included as controls.

RESULTS

We identified 3 patient groups: 1) fulfilling Ghent criteria independent of DE (n = 73), 2); fulfilling Ghent criteria dependent on DE (n = 14), and 3); and suspected MFS, not fulfilling Ghent criteria (n = 18). DE was found in 86% of group 1. At levels L4-S1, mean DSRs were significantly higher in group 1 than in group 3 and controls (P < .001). Herniations of the nerve root sleeves were present in 73% in group 1 versus 1% in controls. Anterior meningoceles were found in 37% and 14% in groups 1 and 2, respectively, but not in group 3 or controls.

CONCLUSIONS

The diagnosis of DE on MR imaging or CT should be based on the presence of at least 1 of the following criteria: anterior meningoceles or nerve root sleeve herniation, DSD at S1 or below larger than DSD at L4, and DSR at S1 >0.59.

The spectrum of syndromes and manifestations in individuals screened for suspected Marfan syndrome

The diagnosis of Marfan syndrome (MFS) is based on evaluating a large number of clinical criteria. We have observed that many persons presenting in specialized centers for "Marfan-like" features do not have MFS, but exhibit a large spectrum of other syndromes. The spectrum of these syndromes and the distribution of "Marfan-like" features remain to be characterized. Thus, we prospectively evaluated 279 consecutive patients with suspected MFS (144 men and 135 women at a mean age of 34+/-13 years) for presence of 27 clinical criteria considered characteristic of MFS. The most frequent reasons to refer individuals for suspected MFS were skeletal features (31%), a family history of MFS, or aortic complications (29%), aortic dissection or aneurysm (19%), and eye manifestations (9%). Using established criteria, we confirmed MFS in 138 individuals (group 1) and diagnosed other connective tissue diseases, both with vascular involvement in 30 (group 2) and without vascular involvement in 39 (group 3), and excluded any distinct disease in 72 individuals (group 4). Clinical manifestations of MFS were present in all four patient groups and there was no single clinical criterion that exhibited positive and negative likelihood ratios that were per se sufficient to confirm or rule out MFS. We conclude that "Marfan-like" features are not exclusively indicative of MFS but also of numerous, alternative inherited diseases with many of them carrying a hitherto poorly defined cardiovascular risk. These alternative diseases require future study to characterize their responses to therapy and long-term prognosis.

Clinical and molecular study of 320 children with Marfan syndrome and related type I fibrillinopathies in a series of 1009 probands with pathogenic FBN1 mutations

From a large series of 1009 probands with pathogenic FBN1 mutations, data for 320 patients <18 years of age at the last follow-up evaluation were analyzed (32%). At the time of diagnosis, the median age was 6.5 years. At the last examination, the population was classified as follows: neonatal Marfan syndrome, 14%; severe Marfan syndrome, 19%; classic Marfan syndrome, 32%; probable Marfan syndrome, 35%. Seventy-one percent had ascending aortic dilation, 55% ectopia lentis, and 28% major skeletal system involvement. Even when aortic complications existed in childhood, the rates of aortic surgery and aortic dissection remained low (5% and 1%, respectively). Some diagnostic features (major skeletal system involvement, striae, dural ectasia, and family history) were more frequent in the 10- to <18-year age group, whereas others (ascending aortic dilation and mitral abnormalities) were more frequent in the population with neonatal Marfan syndrome. Only 56% of children could be classified as having Marfan syndrome, according to international criteria, at their last follow-up evaluation when the presence of a FBN1 mutation was not considered as a major feature, with increasing frequency in the older age groups. Eighty-five percent of child probands fulfilled international criteria after molecular studies, which indicates that the discovery of a FBN1 mutation can be a valuable diagnostic aid in uncertain cases. The distributions of mutation types and locations in this pediatric series revealed large proportions of probands carrying mutations located in exons 24 to 32 (33%) and in-frame mutations (75%). Apart from lethal neonatal Marfan syndrome, we confirm that the majority of clinical manifestations of Marfan syndrome increase with age, which emphasizes the poor applicability of the international criteria to this diagnosis in childhood and the need for follow-up monitoring in cases of clinical suspicion of Marfan syndrome.

Spinal deformities in Marfan syndrome

Marfan syndrome is a connective tissue disease that affects the skeletal system among other organ systems. Kyphoscoliosis, spondylolisthesis, and atlantoaxial subluxation are common spinal deformities in Marfan syndrome, and distinctive vertebral morphology within such patients presents significant treatment challenges. Although most scoliosis curves in patients who have Marfan syndrome are minor, those that require treatment progress rapidly; brace treatment has proven ineffective for most patients. Surgical correction is associated with complications, such as failure of fixation and additional deformity; however good results are possible when consideration is given to the unique challenges presented by patients who have Marfan syndrome.

Magnetic resonance imaging of cauda equina syndrome in long-standing ankylosing spondylitis

The cauda equina syndrome is an uncommon complication of long-standing ankylosing spondylitis and its aetiology is controversial. We report a case of the cauda equina syndrome, erosion of the posterior elements of the lumbar spine and traction of the lumbar nerve roots because of multiple dural diverticula in a patient with long-standing ankylosing spondylitis. Magnetic resonance imaging is valuable in excluding other spinal lesions. Extensive dural diverticula formation is characteristic of ankylosing spondylitis and has the potential to provide an early diagnosis.

Marfan syndrome: what internists and pediatric or adult cardiologists need to know

Marfan syndrome (MFS) is one of the most frequent connective tissue disorders, showing striking pleiotropism and clinical variability. There is autosomal dominant inheritance with complete penetrance but variable expression. Approximately 25% of MFS patients have no family history of the syndrome and represent sporadic cases due to new mutations. This hazardous condition is often associated with premature cardiovascular death unless surveillance and management are optimized. The fibrillin gene (FBN1) encodes the structure of the connective tissue protein fibrillin. MFS is caused by mutations in the fibrillin gene, located on chromosome 15 at locus 15q21. Fibrillin abnormalities reduce the structural integrity of different body systems, primarily involving the heart valves, blood vessels, lungs, bones, tendons, ligaments, cartilages, eyes, skin, spinal dura and the CNS. Patients with MFS are likely to have too little fibrillin within these structures, resulting in clinically relevant problems. For example, in the aortic wall, deficient fibrillin may trigger progressive aortic ectasia and may result in aortic dissection.