Lumbosacral Magnetic Resonance Research Articles

Multiparametric Large Field of View Rheumatology Imaging for Axial Spondyloarthropathy Detects Enthesitis in Setting of Inactive Sacroiliac Joint Disease and Impacts Clinical Diagnosis.

To test the diagnostic efficacy of a multiparametric rheumatology lumbosacral magnetic resonance (MR) imaging protocol in detection and characterization of axial spondylarthritis (SpA) and compare it with serology and clinical findings. A consecutive series of multiparametric rheumatology lumbosacral MR imaging examinations performed on 3T MR scanner. Three-dimensional inversion recovery turbo spin echo, precontrast and postcontrast fat-suppressed T1-weighted images, as well as diffusion-weighted images were used to detect active erosions and enthesitis using established criteria. Pearson χ2 was used for categorical variables. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were measured for magnetic resonance imaging (MRI) and serology, based on the final diagnosis from rheumatologists. An alpha error below 0.05 was considered statistically significant. The final study sample included 130 consecutive patients (80 women and 50 men; mean ± SD 44 ± 13 and 45 ± 14 years, respectively). Seventy-eight subjects were diagnosed with axial SpA and 52 with non-SpA arthropathy. In the non-SpA group, 27 patients were diagnosed with osteoarthritis, 6 had unremarkable imaging, whereas 19 were considered as clinically undetermined. There was positive correlation between positive MRI results and SpA diagnosis (P < 0.00001). No correlation existed between positive serology alone and SpA diagnosis (P = 0.0634). Although MRI and serology proved equally sensitive in detecting SpA, the specificity and overall accuracy of MRI were significantly higher. Inflammatory activity was detected in 45 (57.7%) cases, in the pelvic enthesis in 29 (37.2%) cases, in the lumbosacral spine in 16 (20.5%) cases, in the hip joints in 15 (19.2%) cases, and in the pubic symphysis in 5 (6.4%). Inactive sacral disease was seen in 7 of 35 enthesitis patients (20.0%), and in 2 SpA cases, there were no sacral lesions. The results suggest that in patients with suspected SpA, MRI should not be limited to the sacroiliac joints, but also include enthesitis sites and other joints of the axial skeleton. The multiparametric rheumatology protocol increases the efficacy of MRI in detecting enthesitis and joint inflammatory disease, thereby offering additional information to the clinician and assisting in the early diagnosis/detecting disease activity.

Prevalence and Association of Occult Spinal Dysraphism with Anorectal Malformation

Background: Anorectal malformation (ARM) is associated with occult spinal dysraphism (OSD). The guideline for screening for OSD in patients with ARM is still controversial. Objective: 1) To evaluate the prevalence of OSD in each type of ARM and to elucidate which types of ARM should be screened for underlying OSD. 2) To compare the methods used in radiologic screening for OSD, such as plain lumbosacral X-ray, spinal ultrasound (U/S), and spinal magnetic resonance imaging (MRI). Materials and Methods: The medical records of all patients with ARM treated at Siriraj Hospital between 2006 and 2016 were reviewed. Spinal dysraphism screening with lumbosacral X-ray, U/S, or MRI were performed depending on the surgeon’s request. Associated urinary tract anomalies were noted. Data of the surgical treatments, outcomes, and complications of treatments were collected. Results: Among the 204 ARM patients treated, 150 patients were screened for OSD, involving 150 lumbosacral X-ray, 65 U/S, and 39 MRI. The prevalence of OSD (n=33) in all types of ARM was 16.2%. The higher types of ARM had higher prevalence of OSD, except for vestibular fistula (20.5%). The prevalence of OSD in cloaca malformation, rectobladder neck fistula, rectoprostatic urethral fistula, rectobulbar urethral fistula, and perineal fistula were 28.6%, 33.3%, 16.7%, 12.5%, and 9.8%, respectively. Lumbosacral X-ray had a sensitivity of 51.7% and was not a good screening method. Sixteen of 65 U/S revealed OSD (24.6%). Tethered cord and syringomyelia were noted in nine and seven, respectively. Spinal MRI (n=39) revealed 27 OSD (69.2%) comprising 16 tethered cords, 12 spinal lipoma, and 10 syringomyelia. ARM associated with KUB anomalies had a statistically significant correlation with OSD. In 33 OSD, 17 patients (51.1%) were operated on. Fourteen received untethering spinal cord, while five had intradural lipoma excised. Conclusion: Patients with ARM had a high prevalence of OSD and should be screened for. U/S is the first-line method. MRI is strongly recommended in cloaca malformation, rectobladder neck fistula, rectoprostatic urethral fistula, vestibular fistula, and all ARM associated with KUB anomalies. Other types of ARM should be screened by MRI if feasible. Keywords: Spinal dysraphism, Tethered cord, Anorectal malformation

IMAGE CORRELATION BETWEEN FACET EFFUSION AND LUMBAR INSTABILITY

ABSTRACT Objective To assess the incidence of facet effusion in lumbosacral spine magnetic resonance imaging (MRI) and the relationship with radiographic segmental instability in patients submitted to spinal surgery. Methods Retrospective cohort study of patients submitted to lumbosacral spine surgery over a period of three years, through the evaluation of dynamic radiographs (X-ray) motion and facet effusion in axial section of MRI. Instability was defined as vertebral translation &gt; 3 mm or intervertebral angle &gt; 10º, and facet effusion as fluid in the facet joints &gt; 1.5 mm. Results The total number of patients that fulfilled the criteria for analysis was 244, of which 47 presented movement (≤ 3 mm) and 31 presented excessive movement (&gt; 3 mm), 115 had facet effusion (≤ 1.5 mm) and 46 presented excessive fluid (&gt; 1.5 mm). Statistical analysis did not demonstrate a significant association between increased segmental movement and facet effusion (p = 0.150). Conclusions The total incidence of facet effusion was 47.1% and the excessive fluid was 18.9%.There was no association between facet effusion in MRI and instability in dynamic X-ray. MRI does not replace dynamic X-ray in flexion and extension in the evaluations of lumbar instability. Level of evidence III; Retrospective Cohort.

Diagnostic Accuracy of Lumbosacral Spine Magnetic Resonance Image Reading by Chiropractors, Chiropractic Radiologists, and Medical Radiologists.

A cross-sectional diagnostic accuracy study was conducted in 2 sessions. It is important to know whether it is possible to accurately detect "specific findings" on lumbosacral magnetic resonance (MR) images and whether the results of different observers are comparable. Health care providers frequently use magnetic resonance imaging in the diagnostic process of patients with low back pain. The use of MR scans is increasing. This leads to an increase in costs and to an increase in risk of inaccurately labeling patients with an anatomical diagnosis that might not be the actual cause of symptoms. A set of 300 blinded MR images was read by medical radiologists, chiropractors, and chiropractic radiologists in 2 sessions. Each assessor read 100 scans in round 1 and 50 scans in round 2. The reference test was an expert panel.For all analyses, the magnetic resonance imaging findings were dichotomized into "specific findings" or "no specific findings." For the agreement, percentage agreement and κ values were calculated and for validity, sensitivity, and specificity. Sensitivity analysis was done for classifications A and B (prevalence of 31% and 57%, respectively). The intraobserver κ values for chiropractors, chiropractic radiologists, and medical radiologists were 0.46, 0.49, and 0.69 for A and 0.55, 0.75, and 0.64 for B, respectively.The interobserver κ values were lowest for chiropractors (0.28 for A, 0.37 for B) and highest for chiropractic radiologists (0.50 for A, 0.49 for B).The sensitivities of the medical radiologists, chiropractors, and chiropractic radiologists were 0.62, 0.71, and 0.75 for A and 0.70, 0.74, 0.84 for B, respectively.The specificities of medical radiologists, chiropractic radiologists, and chiropractors were 0.82, 0.77, and 0.70 for A and 0.74, 0.52, and 0.61 for B, respectively. Agreement and validity of MR image readings of chiropractors and chiropractic and medical radiologists is modest at best. This study supports recommendations in clinical guidelines against routine use of magnetic resonance imaging in patients with low back pain. 3.

PP13.11 – 2904: Severe onset and rapidly progressive acute motor axonal neuropathy in a 2-year-old male

Objective Guillain-Barre syndrome (GBS) is an immunomediated polyneuropathy and an important cause of acute neuromuscular paralysis. AMAN is a relatively aggressive disease comparing to Acute Inflammatory Demyelinating Polyradiculoneuropathy (AIDP) and its onset is usually more severe. Methods Herein we present an AMAN case which was presented with rapidly progressive flaccid paralysis. Results 2 year-old male patient was brought to emergency room because of losing ability to walk. According to his parents' statements, he started to have difficulties while walking 12 hours ago, and he couldn't walk at all in the last hour. Patient lost motor control of his head in the follow up on the sixth hour. Because of this rapid and progressive onset and ascending flaccid tetraplegia patient was taken into the intensive care unit. On the thirty-sixth hour of the observation, patient required intubation and mechanical ventilation, due to cranial neuropathy and respiratory failure. His cerebrospinal fluid protein level was 48 mg/dl (15–45 mg/dl), and no cells were detected. Similarly, stool culture was negative for campylobacter jejuni. GQ1B, GD1B, GD1A, GM1 antibodies were studied and results were negative. Lumbosacral spinal magnetic resonance imaging was performed and contrast enhancement in conus medullaris level was detected. Electromyography was performed and findings were associated to AMAN. Initial treatment regime was 400 mg/kg/day intravenous immunoglobulin for five days. However, because of the ongoing progression, consecutive intravenous immunoglobulin and plasma exchange therapies were given. After four weeks of progression, patient stayed in the plateau phase for another four weeks, and descendent healing began subsequently. Conclusion There are a variety of forms of the GuillainBarre Syndrome. Although it can be seen in all age groups, it is relatively rare in patients under 2 years of age In selected cases like this one, consecutive plasmapheresis and intravenous immunoglobulin therapies should be considered.

Spinal Primitive Neuroectodermal Tumor Mimicking as Chronic Inflammatory Demyelination Polyneuropathy

We report a young boy who presented with progressive weakness of lower extremities associated with areflexia and abnormal electrophysiological findings initially suggestive of chronic inflammatory demyelinating polyneuropathy. Initial lumbosacral spinal magnetic resonance imaging (MRI) showed thickened descending spinal nerve roots only. Immunomodulating therapy was given but with limited clinical response. Repeated spine magnetic resonance imaging showed cauda equina and also new spinal cord extramedullary contrast enhancement. The initial extensive investigations including open biopsy did not point to any specific diagnosis. Only through pursuing a repeated biopsy, the diagnosis of the spinal peripheral primitive neuroectodermal tumor was confirmed. This case highlights the diagnostic challenges of the spinal peripheral primitive neuroectodermal tumor that could have an initial chronic inflammatory demyelinating polyneuropathy-like presentation. The literature review confirms that this is a rare condition and cauda equina origin has only been reported in adults and teenagers, and this is the first reported case in a young child.

Distribution of Epidural Saline Upon Injection and the Epidural Volume Effect in Pregnant Women

How injected epidural solution is distributed and affects the epidural volume in pregnant women are unclear. Lumbar epidural catheters were placed using the loss-of-resistance technique with saline in eight full-term (39 weeks' gestation) parturients for labor and eight volunteer nonpregnant women. Lumbosacral cerebrospinal fluid volume was measured on thoracic and lumbosacral axial magnetic resonance images. Another image series was obtained after injecting 10 ml saline into the epidural space through the catheter to compare the saline distribution (dural sac coating and exit from foramina) and cerebrospinal fluid volume before and after epidural injection. Dural sac coating was based on observation of epidural saline in the anterior epidural space after injection in axial magnetic resonance images at the pedicle levels from T12 to L5. Saline leakage from the foramina was determined by the same method at six disc levels from T11-T12 to L4-L5. Significantly fewer images of pregnant women than nonpregnant women showed saline surrounding the dural sac (0 [0-0] vs. 3 [1-4], median [interquartile range]; P < 0.01) and saline leakage from the foramina (0 [0-1] vs. 6 [4-6]; P < 0.01). The mean reduction in cerebrospinal fluid volume was significantly greater in pregnant (8.4 ± 1.4 ml; mean ± SD) than in nonpregnant women (4.6 ± 1.1 ml; P < 0.001). Limited dural sac coating and decreased leakage from the foramina of saline injected into the epidural space may account for the facilitation of longitudinal spread of epidural analgesia in pregnant women. The epidural volume effect is greater in pregnant than in nonpregnant women.

A patient with Bartter syndrome accompanying severe growth hormone deficiency and focal segmental glomerulosclerosis

Bartter syndrome is a rare autosomal recessive, salt-losing disorder characterized by hypokalemic hypochloremic metabolic alkalosis. A 10-year-old boy had severe growth retardation (height standard deviation score -8.15). He had a thin, triangular face, prominent ears and forehead, and big eyes. Megacystis, bilateral hydroureteronephrosis, and residual urine were detected in ultrasonography, but there was no vesicoureteral reflux. Lumbosacral magnetic resonance (MR) showed posterior disc bulging at L4-5. Serum sodium and chloride levels were normal, but mild hypokalemia was overlooked initially. During follow-up, hypokalemic hypochloremic metabolic alkalosis developed, with high urinary chloride and potassium excretion (52 and 43 mEq/L, respectively). The patient, with renal salt loss, was thought to have classic Bartter syndrome due to absence of nephrocalcinosis, presence of persistent hypercalciuria and sensorineural deafness, and presence of relatively mild clinical and laboratory findings, except polyuria initially. The child was treated with indomethacin, spironolactone, and oral potassium in addition to growth hormone (GH). During treatment, he had considerable increase in weight and height compared with the period of GH therapy only. We present this case because, although growth retardation is a major feature of Bartter syndrome, associated GH deficiency is rarely reported in the literature. Diagnosis of Bartter syndrome was made later, as our patient was followed for megacystis and megaureter secondary to the neurogenic bladder and GH deficiency initially; and proteinuria associated with focal segmental glomerulosclerosis responded to treatment for Bartter syndrome.

Incidental abdominal aortic aneurysm on lumbosacral magneticresonance imaging — a case series

Magnetic resonance imaging (MRI) is commonly used as part of the assessment of patients presenting with leg/back pain to the orthopedic spinal outpatient clinic. Abdominal aortic aneurysm (AAA) can cause symptoms often similar to those of spinal stenosis. We report a case series of four patients who had incidental AAA detected on lumbosacral MRI. All patients were suffering from degenerative spinal disease and had been referred to the orthopedic spinal clinic. After history, examination and review of the imaging, all patients were referred to a vascular surgeon, and three were found to be completely asymptomatic from their aneurysm. One patient required open repair with an aortic graft due to the size of the aneurysm, although his symptoms were attributable to his spinal disease. All patients still required management of their degenerative spinal disease after their vascular review. We can find no other case reports of AAA as an incidental finding on lumbosacral MRI. This case series highlights the importance of looking at all aspects of our imaging and remembering the nonspinal causes of back and leg pains. Furthermore, in the presence of AAA when managing patients in the orthopedic outpatient setting, the authors recommend vascular review before offering orthopedic interventional management options to these patients.

A huge presacral Tarlov cyst

Perineural cysts have become a common incidental finding during lumbosacral magnetic resonance (MR) imaging. Only some of the symptomatic cysts warrant treatment. The authors describe the successful operative treatment of a patient with, to the best of their knowledge, the largest perineural cyst reported to date. A 29-year-old woman had been suffering from long-standing constipation and low-back pain. During an obstetric investigation for infertility, the clinician discovered a huge presacral cystic mass. Computed tomography myelography showed the lesion to be a huge Tarlov cyst arising from the left S-3 nerve root and compressing the ipsilateral S-2 nerve. The cyst was successfully treated by ligation of the cyst neck together with sectioning of the S-3 nerve root. Postoperative improvement in her symptoms and MR imaging findings were noted. Identification of the nerve root involved by the cyst wall, operative indication, operative procedure, and treatment of multiple cysts are important preoperative considerations.