Infection after intradiscal injections has been recognised as a distinct entity, but discitis after discography has often been attributed to an aseptic process or a chemical reaction to the contrast material. We examined the hypothesis that discitis after discography is always due to infection, and report a clinical review and an experimental study. Part I. We reviewed the case records and radiographs of 432 patients who had undergone lumbar discography. When an 18-gauge needle without a stilette had been used, discitis was diagnosed in 2.7% of 222 patients but stiletted needles and a two-needle technique at each level reduced the incidence to 0.7%. Seven patients with discitis after discography had undergone anterior discectomy and fusion; in them the histopathological findings were of a chronic inflammatory response. Bacteria were isolated from the discs of three of the four patients who had open biopsy less than six weeks from the time of discography. These findings suggest that bacteria were initiators rather than promoters of the response. Part II. Multiple level lumbar discography was carried out in mature sheep, injecting contrast material with or without various concentrations of bacteria. Radiographs were taken and the discs and end-plates were examined histologically and cultured for bacteria at intervals after injection. None of the controls showed any evidence of discitis but all sheep injected with bacteria had typical radiological and histopathological changes by six weeks, though cultures were almost all negative. However, at one and two weeks after injection, but usually not after three weeks, bacteria could be isolated. We suggest that all cases of discitis after discography are initiated by infection, and that a very strict aseptic technique should be used for all injections into intervertebral discs

Introduction Historically, lumbar discography has been one of the most controversial subjects in the management of discogenic low back pain. The diagnostic value of normal psychometric specific pain provocation by disc pressurization has emerged. The sensitivity, specificity and accuracy of discography as a diagnostic test are not in doubt. In clinical discography pain reproduction and location are essential elements. There is an accepted rate of 0–10% false positives. This rate is influenced by occupational disability and abnormal psychometric profiles. By contrast, little attention has been given to false negative results and their outcomes if surgically treated. Traditionally, whether or not the test is considered to be positive or negative is determined immediately after completion of the diagnostic procedure. This study shows that patient’s pain reproduction may occur up to 24 hours after the discogram which often initially interpreted as a true negative when it is actually a false negative result. This study verifies the existence and significance of a false negative through the patients’ treatment and outcomes. Methods In this study, 150 patients underwent discography for investigation of chronic persistent low back pain (CPLBP). All patients had a control (morphologically normal) discogram at the level above the degenerative segment. No patients with abnormal psychometric profiles or compensation were included. All patients were followed up 24 hours post discogram by the radiologist to further assess their clinical status. Ten of the patients (7.5%) were considered to have a false negative discogram, as per the Dallas Discogram Scale. The surgeon correlated the delayed response on the subsequent follow-up. These ten patients were diagnosed as having a positive response and were treated surgically for their discogenic pain. VAS-B, VAS-L, ODI, RMD were collected prospectively. Preoperative and 6 month results were reviewed. Results Seven of the 10 patients (70%) reported severe increase CPLBP and reproduction of pain within 8 hours of the discogram, while 3 patients (30%) did so in the ensuing 24 hours after the discogram. Surgical treatment was either by total disc replacement or anterior lumbar interbody fusion. All patients reported greater than 50% reduction in VAS-B and VAS-L and with improvements of greater than 50% in their ODI and RMD scores. Discussion The clinical reliability of discography hinges on the subjective assessment of pain concordance as the discriminating factor in determining false positives from false negatives. Given the limitations of discography, all information about the patient should be considered prior to diagnosis, including clinical, radiological, historical, and psychometric factors. The delayed positive discography response is an important consideration for the patient, the radiologist, and the treating surgeon to be aware of. The results of this study verify the existence of this subgroup and justify their surgical treatment

Aims. The presence of facet tropism has been correlated with an elevated susceptibility to lumbar disc pathology. Our objective was to evaluate the impact of facet tropism on chronic lumbosacral discogenic pain through the analysis of clinical data and finite element modelling (FEM). Methods. Retrospective analysis was conducted on clinical data, with a specific focus on the spinal units displaying facet tropism, utilizing FEM analysis for motion simulation. We studied 318 intervertebral levels in 156 patients who had undergone provocation discography. Significant predictors of clinical findings were identified by univariate and multivariate analyses. Loading conditions were applied in FEM simulations to mimic biomechanical effects on intervertebral discs, focusing on maximal displacement and intradiscal pressures, gauged through alterations in disc morphology and physical stress. Results. A total of 144 discs were categorized as ‘positive’ and 174 discs as ‘negative’ by the results of provocation discography. The presence of defined facet tropism (OR 3.451, 95% CI 1.944 to 6.126) and higher Adams classification (OR 2.172, 95% CI 1.523 to 3.097) were important predictive parameters for discography-‘positive’ discs. FEM simulations showcased uneven stress distribution and significant disc displacement in tropism-affected discs, where loading exacerbated stress on facets with greater angles. During varied positions, notably increased stress and displacement were observed in discs with tropism compared to those with normal facet structure. Conclusion. Our findings indicate that facet tropism can contribute to disc herniation and changes in intradiscal pressure, potentially exacerbating disc degeneration due to altered force distribution and increased mechanical stress. Cite this article: Bone Joint Res 2024;13(9):452–461

In a prospective study we attempted to define the role of lumbar discography in the investigation of patients with low back pain with or without non-dermatomal pain in the lower limb. The records of 195 patients were studied at least two years after a technically successful operation. Of 137 patients in whom discography had revealed disc disease and provoked symptoms, 89% derived significant and sustained clinical benefit from operation. Of 25 patients whose discs showed morphological abnormality but had no provocation of symptoms on discography only 52% had clinical success. These findings support the continued use of lumbar discography for the investigation of this particular group of patients

Discitis after discography is due to bacterial penetration into the intervertebral disc by a contaminated needle and has an incidence of 1% to 4%. We have examined the prophylactic role of cephazolin administered at the time of discography. An experimental study in sheep using radiographic contrast containing Staphylococcus epidermidis showed that either adding the antibiotic to the intradiscal suspension or giving it intravenously 30 minutes before intradiscal inoculation of bacteria prevented any radiographic, macroscopic or histological signs of discitis; all the intervertebral disc cultures were negative. In a prospective clinical study of 127 consecutive patients having lumbar discography, the injected contrast contained cephazolin 1 mg per ml. None of the patients developed clinical or radiographic signs of discitis. We recommend the use of a suitable broad spectrum antibiotic in a single prophylactic dose whenever the intervertebral disc is entered

We attempted to correlate the findings of MRI and discography in patients with low back pain, examining 108 lumbar intervertebral discs in 33 consecutive patients. MRI results were assessed from the intensity and shape of the signal obtained from the central part of the disc. Discography was classified according to the pattern of contrast material, the pressure accepted and the pain reproduced. All discs which were abnormal on MRI had altered patterns on discography, but 18 of the 60 discs with normal MRI had abnormal discograms. Of 39 asymptomatic discs, 33 had normal MRI signals and 24 had normal discograms. None of the 15 discs showing severe degeneration on MRI sustained high levels of intradiscal pressure, but only six of the 60 discs giving normal MRI had low pressure. With current techniques, discography is more accurate than MRI for the detection of annular pathology: a normal MRI does not exclude significant changes in the peripheral structure of the intervertebral disc which can produce low back pain

Prospective match cohort study of disc degeneration progression over ten years with and without baseline discography. To compare progression of common degenerative findings between lumbar discs injected ten years earlier with those same disc levels in matched subjects not exposed to discography. Seventy-five subjects without serious low back pain illness underwent a protocol MRI and a L3/4, L4/5 and L5 S1 discography in 1997. A match group was enrolled at the same time and underwent the same protocol MRI examination. Subjects were followed for ten years. At 7 to 10 years after baseline assessment, eligible discography in controlled subjects underwent another protocol MRI. MRI graders, blind to group designation, scored both groups for qualitative findings. Well matched cohorts, including 50 discography subjects and 52 control subjects met eligibility criteria for follow up evaluation. In all graded or measured parameters, discs that had been exposed to puncture and injection had greater progression of degenerative findings compared to control (non-injected) discs: progression of disc degeneration, 54 discs (35%) in the discography group compared to 21 (14%) in the control group (p=0.03); 55 new disc herniations in the discography group compared to 22 in the control group (p=0.0003). New disc herniations were disproportionately found on the side of the annular puncture (p=0.0006). The quantitative measures of disc height and disc signal also showed significantly greater loss of disc height (p=0.05) and signal intensity (p=0.001) in the discography disc compared to the control disc. This study demonstrates that the dimensions of the LSP change with age. Increases in LSP height occur with age. More impressive increases in LSP width occur with advancing age. This study suggests that loss of lumbar lordosis is correlated with changing LSP morphology. The increased width of the LSP with age influences access to the spinal canal, particularly if midline-preserving approaches are attempted in the ageing population. There is increased bone volume for bone grafting procedures with increasing age. The reduced distance between LSPs with age may influence design of implants that stabilize this region of the spine, and occur not only as a result of disk space narrowing, but also as a consequence of increased LSP dimensions

Introduction: The role of discography before lumbar fusion had been discussed in the literature. No study discussed its role before total lumbar disc replacement (TDR). Degenerate discs are not necessarily painful, even if they show Modic changes or HIZ. Moreover, discogenic pain might not be the predominant element in the patient’s symptoms and most of the back pain could be originating form other spinal structures. The aim of our prospective cohort study is to show whether or not provocative discography plays any significant role before TDR and to define that role. Methods: Twenty patients (11 females and 9 males) had “Prodisc” TDR. Mean age = 38.5 years (range: 20–56). All patients had mechanical low back pain with degenerative disc disease diagnosed by MRI scan. 65% (N=13) had radicular pain as well. The mean duration of back pain = 66.9 months (range: 16–240). Pre-operative provocative discography was performed in all cases. The clinical outcome was assessed by comparing the preoperative SF36-v2, ODI and VAS scores’ means to the 3, 6, 12 and 24 months post-operative ones and also comparing the last follow up SF36-v2 scores with the, age and sex adjusted, normative data for the general UK population obtained from the Oxford Healthy Lifestyle Survey III. All patients were followed up for a minimum of 2 years. Results: 90% (N=18) experienced a clinically significant improvement of their back pain (MCID for SF36-v2 scales=1SD, ODI=10 points and VAS=2 points). There has been a statistically significant improvement in the follow up outcome measures (P< 0.05) at 3, 6, 12 and 24 mths. SF 36-v2 scores of 15% of patients (N=3) reached or exceeded the normative values for the UK general population. Conclusion: Provocative discography is an important diagnostic tool before TDR. It is the only dynamic method to diagnose discogenic pain and is indispensable to exclude the painless levels in cases of multilevel disc degeneration

This prospective study was carried out to correlate findings of magnetic resonance imaging (MRI) and discography. Fifty-five consecutive patients with degenerative disc disease not responding to non-operative treatment were included in the study. There were 19 men and 36 women and the mean age was 45 years. Discography was carried out on 131 disc levels. The discograms were classified using modified Adams’s classification and pain recorded into three grades. MRI scans were graded using a new classification system based on parasagittal and axial images by two independent observers blinded to discography findings. There was good intraobserver (kappa 0. 74) and interobserver (kappa 0. 70) agreement for the classification system. There was a significant correlation in the morphology of discs as determined by discograms and MRI classification (p< 0. 001). Each disc was graded on MRI scan as painful or painless on basis of defined criteria. Concordant discography pain was considered as the gold standard. The sensitivity and specificity of MRI in predicting symptomatic disc using defined criteria was 94% and 77%. The sensitivities and specificity of high intensity zones was 27% and 87% and for end plate changes was 32% and 98% respectively. In 14 patients (25%) the findings of MRI and discography did not correlate. In conclusion though MRI is an excellent investigation for assessing disc morphology it should be interpreted along with discography findings before planning fusion surgery. The proposed MRI classification is a useful aid in predicting painful degenerative disc. The utility of high intensity zones and end plate changes is limited due to low sensitivity

Two different classifications of discograms have been used in a prospective study of 279 injected discs in 100 patients. The five-stage classification of Adams, Dolan and Hutton (1986) showed increased degeneration in the lower lumbar discs and more degenerative changes in men than in women. Exact reproduction of the patient's pain on injection was more common in fissured or ruptured discs than in less degenerate discs, with 81% sensitivity and 64% specificity of the discogram for pain. The additional information obtained by comparing computerised tomography (CT) with discograms was minimal. Discography was found to be useful in the evaluation of chronic low back pain in patients whose ordinary CT scans, myelograms and flexion-extension radiographs were normal. In spondylolysis and spondylolisthesis, discography can disclose whether fusion needs to be extended above the lytic level, and it may show if the pain in patients who have had posterolateral fusion is discogenic. Thus, discography gives information which is useful in deciding whether to operate on patients with chronic low back pain

We analysed the functional outcome (Oswestry Disability Index) after technically and radiologically successful lumbar fusion in 39 non-compensation seeking patients with chronic low back pain, who had a High Intensity Zone (HIZ) – positive MRI and subsequently underwent discography. The average follow-up was 33 months. The HIZ-positive, discogrampositive group was the only one with statistically significant improvement. The HIZ-positive, discogram-negative group had the worst outcome. Relying only on the HIZ fails to identify the group of patients who would have had negative discography at the same levels. Therefore the presence of HIZ alone should not dictate treatment plan without discography confirmation

Background: Over several decades, investigators have been trying to identify the painful degenerate disc. Their work included two main methods. The first was to set criteria on the radiological investigations, mainly the MRI scan, to describe the severity of the degenerative disc disease (DDD); and the second was to perform discographies. Neither of these two methods precluded the need for the other. Purpose: Using Pfirrmann’s classification, we correlated static MRI images, for the severity of segmental disc degeneration, with dynamic lumbar discography, with the aim to improve the identification of painful ‘disco-genic’ intervertebral segments. Study design: Prospective cohort study. Inclusion criteria included patients with mechanical low back pain who exhausted the conservative measures and required surgical treatment. Patient Sample and Methods: We investigated 69 patients (45 females, 24 males). The average age was 38.9 years (range 20–56). All patients had degenerative disc disease (DDD) on lumbar MRI scans. Provocative discographies were performed in all cases as a routine investigation to identify painful levels prior to fusion or disc replacement surgery. The severity of DDD was graded using Pfirrmann’s classification. A total of 162 discographies were performed using the ‘miss the facet joint, double needle technique’. Outcome measures: During discography typical or concordant pain only was regarded as positive. Among each of the five Pfirrmann grades, the percentage of positive discographies was calculated. Significance and correlation then were investigated using the Chi-squared and Spearman’s correlation tests. Results: 24 discs were classified as Pfirrmann grade I, 33 grade II, 63 grade III, 27 grade IV and 15 grade V. The percentages of positive provocative discography for concordant pain among these groups were 0%, 9.1%, 71.4%, 100% and 100% respectively. Statistical analysis showed a high correlation between the severity of DDD on MRI scan and the result of the provocative discography (Chi2 = 32.96, P < 0.001 and correlation coefficient = 0.756). Conclusion: The higher the grade of segmental DDD, the more likely it will be painful on discography. All discs showing Pfirmann grade IV and V disease were painful on discography. We strongly recommend the Pfirrmann classification for use in grading the severity of lumbar DDD especially when assessing for its association with discogenic pain as determined by provocative discography

The lumbar spines of 22 patients were examined for disc degeneration by magnetic resonance imaging (MRI) and by discography. The results from 50 intervertebral discs visualised by both techniques were independently assessed and graded on a five-point scale from normality to gross degeneration and then compared. In 44 discs the results agreed. Of the six discs which gave differing results, four discrepancies were due to observer error and two to incorrect placement of the discographic needle. MRI was shown to be more accurate than discography in the diagnosis of disc degeneration. It has several major advantages, which should make it the investigation of choice

Introduction: Recent cadaveric studies have identified neovascularisation and neoneuralisation as probable mechanisms in the causation of discogenic pain. Calcium pyrophosphate deposits have been observed in discs in several studies. Their significance in the causation of discogenic pain is unclear. Direct correlation between the pain site and histological features can be verified by aware state endoscopic visualisation. Aim and Objectives: The study aims to examine and correlate the presence of neovascularisation, crystalline pyrophosphate deposits in the disc, and discogenic pain by spinal probing and discography under endoscopic visualisation. Material and Methods: Tissue removed from intervertebral discs of 224 patients during surgery was examined directly, and polarised microscopy was used to identify the presence of calcium pyrophosphate and neovascularisation. Their presence was correlated to diagnostic provocative findings of spinal probing and discography and intradiscal distortion during aware state endoscopy. Results: Calcium Pyrophosphate: Twenty out of 224 patients (9%) demonstrated calcium pyrophosphate in the discs. Fourteen had pain reproduced on probing or discography. Thirteen out of 20 patients (65%) had either an annular collection or leak at the index level. 6 had an extradiscal cause of pain. One hundred percent of the patients with annular collections or leaks had pain on spinal probing or discography. Sixteen patients with pyrophosphate deposits did not have neovascularisation. Neovascularisation: Thirty seven out of 224 patients (16.5%) showed neovascularisation in the disc. Four discs had crystalline pyrophosphate deposits. Thirty three out of 37 (90%) had pain on probing and/or discography. Out of four patients who had no pain on probing or discography, two had demonstrated tears during previous discographic procedures which were treated with laser annealing. These patients had disc bulges and compressive radiculopathy. Conclusion: The presence of pyrophosphate in the disc without a tear or leak does not directly render them tender to provocation. The presence of pyrophosphate is not correlated to neovascularisation. Annular tears or leaks are not directly correlated to the presence of pyrophosphates. There is a high correlation between pain provocation and neovascularisation

Introduction. Degenerative disc disease results from mechanical alteration of the intervertebral disc. Biochemical modifications of the nucleus matrix are also incriminated. Furthermore, genetic predispositions as well as vascular factors have been advocated in the process of disc degeneration. A relationship between sciatica and Propionibacterium acnes has been described. However, it remains unclear if the hypothesis of a subclinical spondylodiscitis might play a role in the pathophysiology of degenerative disc disease. The purpose of this study was to analyze the possible presence of bacteria in lumbar discs of patients with degenerative disc disease. Methods. We prospectively analyzed the presence of bacteria in 83 patients (34 males and 49 females, average age 41 years) treated by lumbar disc replacement at L3-L4, L4-L5 or L5-S1. An intraoperative biopsy and microbiological culture were performed for each disc to determine if intradiscal bacteria were present. Great care was taken to avoid any source of contamination during the conditioning process of the biopsy. Microbiological results were compared to the magnetic resonance stages of disc degeneration according to the Pfirrmann and Modic classifications. Possible sources of previous iatrogenic disc contamination after discography or nucleotomy were analyzed. Results. The magnetic resonance stages were Pfirrmann IV or V, with Modic I signs in 32 and Modic II in 25 cases. A preoperative discography was performed in 49 patients, and 24 had previous nucleotomy. Germs were found in 40 discs, 43 cultures were steriles. The following bacteria were evidenced: Propionibacterium acnes 18, Staphylococcus coagulase negative 16, Staphylococcus aureus 3, Gram negative bacilli 3, Micrococcus 3, Corynebacterium 3, others 5. Ten biopsies presented several different germs. Bacteria were predominantly found in males (p=0.012). The mostly positive level was L4-L5 (p=0.075). Histological examination of 31 discs found inflammatory cells in 33 % of the biopsies with positive bacterial culture, versus 5 % of the sterile biopsies (p=0.038). There was no significant relationship between bacterial evidence and Modic sign. A preoperative discography or previous nucleotomies did not represent significant contamination sources. None of the patients presented clinical signs of infection. Conclusions. The finding of bacteria in 48 % of disc biopsies, presence of inflammatory cells at histological examination, the absence of responsibility of the discography as a factor of contamination, and the absence of clinical post-operative infection, defend the hypothesis of a low-grade spondylodiscitis which might play a role in the pathophysiology of degenerative disc disease. On the other hand, the presence of skin commensal bacteria, of ¼ of polymicrobial biopsies, and the fact that previous nucleotomy doesn't seem to be involved in inoculation, cannot allow to eliminate a contamination of the samples. Further studies are necessary to elucidate the responsability of intradiscal bacteria in degenerative disc disease. This could influence our treatment strategy of back pain, which could be based in the future on antibiotics

Discogenic low back pain is a common cause of disability, but its pathogenesis is poorly understood. We collected 19 specimens of lumbar intervertebral discs from 17 patients with discogenic low back pain during posterior lumbar interbody fusion, 12 from physiologically ageing discs and ten from normal control discs. We investigated the histological features and assessed the immunoreactive activity of neurofilament (NF200) and neuropeptides such as substance P (SP) and vasoactive-intestinal peptide (VIP) in the nerve fibres. The distinct histological characteristic of the painful disc was the formation of a zone of vascularised granulation tissue from the nucleus pulposus to the outer part of the annulus fibrosus along the edges of the fissures. SP-, NF- and VIP-immunoreactive nerve fibres in the painful discs were more extensive than in the control discs. Growth of nerves deep into the annulus fibrosus and nucleus pulposus was observed mainly along the zone of granulation tissue in the painful discs. This suggests that the zone of granulation tissue with extensive innervation along the tears in the posterior part of the painful disc may be responsible for causing the pain of discography and of discogenic low back pain

Objectives: To examine and correlate the presence of neovascularisation, crystalline pyrophosphate deposits and other hisotological features in the disc and discogenic pain established by spinal probing and discography under aware state endoscopic visualisation. Design: Tissue removed from intervertebral discs of 224 patients during surgery were examined by direct and polarised microscopy to identify the presence of calcium pyrophosphate and neovascularisation. Material and Methods: Histology was correlated to the diagnostic provocative findings of spinal probing and discography, discal palpation during aware state endoscopy. Results:Calcium Pyrophosphate: 20/224 (9%) patients demonstrated calcium pyrophosphate in the discs. Fourteen had pain reproduced on probing or discography; 13/20 (65%) of patients had either an annular collection or leak at the index level; 6/20 had an extradiscal cause of pain. Neovascularisation: Thirty-seven out of 224 (16.5%) patients showed neovascularisation in the disc; four discs had crystalline pyrophosphate deposits; 33/37 (90%) had pain on probing and/or discography. Conclusion: The presence of pyrophosphate in a disc without a tear or leak is not associated with annular tenderness. The presence of pyrophosphates in radial tears or leaks is associated with annular tenderness. Annular tears or leaks are not directly correlated to the presence of pyrophosphates. There is a high correlation between pain provocation and neovascularisation

Problem Chronic disabling pain in the sacrococcygeal region is regarded by clinicians with great dismay because of unpredictability of the treatment outcome. The subject is under- represented in the literature. Method Thirty eight patients with intractable coccydynia had imaging investigations for the spine other than X-rays. Six of these patients were also investigated by means of sacrococcygeal and intercoccygeal discography. The excised specimen with intact sacrococcygeral joint was sent for histological examination in 22 patients. Patients’ assessment of the benefit of coccygectomy was conducted by telephonic interview. Results After a mean post surgical follow up of 6.75 years (range 2–16 yrs), results were available for 31 out of 38 patients. 16 patients benefited greatly from the surgery and 6 benefited to some extent, giving an overall good result of 71%. 7 patients had no or little relief from surgery (29%). Moderate to severe degenerate changes in SC and IC joints on histology were found in 59% of patients. 91.6 % of these patients did well with surgery. Only 60 % of those with mild changes did well. Discography was possible in five out of six attempted cases. Two were positive and both did well from surgery. Three patients had negative discographies and two of them had a poor result and one had only some relief. Conclusions Degenerate changes in sacrococcygeal discs give rise to pain. Surgical results are better in those with a severe degree of degenerative change. It is possible to identify these with discography, though a larger study needs to be carried out

Purpose. By systematic literature review, to quantify the association between vertebral endplate signal changes (VESC) and non-specific low back pain (NSLBP). Materials and methods. MEDLINE, EMBASE, and SveMED databases were searched for the period 1984 to June 2009. Articles were included which investigated the association between VESC and NSLBP and reported sufficient data to construct two-by-two tables. Articles on specific low back pain conditions were excluded. A standardised data collection and quality assessment were performed. To estimate the association between VESC and NSLBP, two-by-two tables were created and exact odds ratios were calculated with 95% confidence intervals (CI). Meta-analysis was performed on homogeneous studies. Results. Fourteen articles met the inclusion criteria. A statistically significant positive association between VESC and NSLBP was found in 10 of 14 studies from the general, working, and clinical populations with odds ratios ranging from 2.0 to 27.9. Two of the other four studies showed positive associations, one study a neutral association and the other a negative association but all these results were not statistically significant. Meta-analysis of the eight discography studies included in the review showed a pooled odds ratio between VESC and pain on discography of 4.50 (CI 1.96-10.32). The median prevalence of pain on discography was 88.8% in people with VESC and 41.6% in those without VESC (46.8% overall). Conclusions. The results from this systematic review show that VESC in the lumbar spine is associated with pain and therefore should be noted routinely in MRI reports