Evaluation of the current use of MRI to aid the diagnosis of axial spondyloarthritis in the UK: results from a freedom of information request.

AIM: To evaluate the impact of recommendations from the 2019 consensus exercise conducted by radiologists and rheumatologists on the use of magnetic resonance imaging (MRI) to investigate axial spondyloarthritis (axSpA) in clinical practice. MATERIALS AND METHODS: A freedom of information (FOI) request was used to assess the use of MRI in the diagnosis of axSpA and radiologists' awareness of the 2019 guidance across all NHS Trusts and Health Boards in the UK, including England, Scotland, Northern Ireland, and Wales. RESULTS: The FOI request was sent to 150 Trusts/Health Boards, and 93 full responses were received. Of the 93 respondents (97%), 90 reported familiarity with the term axSpA and 70/93 (75%) reported familiarity with the 2019 recommendations. Awareness of recommendations regarding specific MRI features supportive of the diagnosis of axSpA was 74/93 (80%) for the sacroiliac joints (SIJs) and 66/93 (71%) for the spine. The median wait for MRI acquisition was 2-3 months. Fifty-two of the 93 (56%) reported at least some outsourcing of axSpA MRI (33%/29% for specialist/non-specialist outsourcing respectively); 32/93 (34%) reported some scans being reported in-house by non-musculoskeletal radiologists. CONCLUSION: There have been several positive developments in the understanding and use of MRI for the diagnosis of axSpA in the UK since the 2017 survey, although substantial scope for further improvement remains. Several new challenges have also emerged, including the increase in waiting times, reliance on outsourcing, and the reporting of MRI by non-musculoskeletal radiologists.

Quantifying bone structure, micro-architecture, and pathophysiology with MRI.

The radiology of bone has been transformed by magnetic resonance imaging, which has the ability to interrogate bone's complex architecture and physiology. New techniques provide information about both the macrostructure and microstructure of bone ranging from micrometre detail to the whole skeleton. Furthermore functional information about bone physiology can be used to detect disease early before structural changes occur. The future of bone imaging is in quantifying the anatomical and functional information to diagnose and monitor disease more precisely. This review explores the state of the art in quantitative MRI bone imaging.

Is imaging the future of axillary staging in breast cancer?

Axillary management in patients with breast cancer has become much less invasive with the introduction of sentinel lymph node biopsy (SLNB). However, over 70 % of SLNBs are negative, questioning the generic use of this invasive procedure. Emerging evidence indicates that breast cancer patients with a low axillary burden of disease do not benefit from axillary lymph node dissection (ALND). Non-invasive techniques such as paramagnetic iron oxide contrast-enhanced magnetic resonance imaging (MRI) may provide genuine alternatives to axillary staging and should be evaluated within clinical trials. Selective axillary surgery could then be offered based on imaging findings and for therapeutic intent. This non-operative approach would reduce morbidity further and facilitate interpretation of follow-up imaging. Key Points • Modern imaging and biopsy greatly help the axillary staging of breast cancer. • Superparamagnetic iron oxide (SPIO)-enhanced MRI offers a further advance. • Sentinel lymph node biopsy may become redundant with SPIO-enhanced MRI. • Selective therapeutic axillary surgery should be based upon preoperative imaging findings.

Transverse vaginal septae: management and long-term outcomes.

OBJECTIVE: To examine the management and long-term outcomes of transverse vaginal septae. DESIGN: Observational study with cross-sectional and retrospective arms. SETTING: Tertiary referral centre specialising in Müllerian anomalies. POPULATION: Forty-six girls and women with a transverse vaginal septum. METHODS: Data from medical records of all cases (1998-2013) of transverse vaginal septae were collected and reviewed. Patients over 16 years of age also completed a questionnaire. MAIN OUTCOME MEASURES: Presentation, examination findings, investigations, surgery, and long-term reproductive outcomes. RESULTS: The septae in the study were described as follows: 61% (95% CI 0.46-0.74) were imperforate, and presented with obstructed menstruation; 39% (95% CI 0.26-0.54) were perforate, and presented with a variety of concerns; 72% (95% CI 0.57-0.83) were low, 22% (95% CI 0.12-0.36) were mid-vaginal, and 6% (95% CI 0.02-0.18) were high; 33% were managed via an abdominoperineal approach, 59% were managed via a vaginal approach, and 6% had laparoscopic resection (one patient did not have surgery); 11% (95% CI 0.05-0.23) of patients presented with reobstruction, all following abdominoperineal vaginoplasty; 7% presented with vaginal stenosis, two following vaginal resection and one following the abdominoperineal approach; 61% of questionnaires were returned. These results showed that 22/23 patients were menstruating and one had a hysterectomy, 74% had been sexually active, 35% had dyspareunia, and 36% complained of dysmenorrhoea. There were seven pregnancies, with one termination and six live births, all following the vaginal excision of a transverse vaginal septum. CONCLUSIONS: Transverse vaginal septae resected vaginally or laparoscopically have low complication rates and good long-term outcomes. Complex septae require more extensive surgery, with an increased risk of complications.

A phase II study of weekly neoadjuvant chemotherapy followed by radical chemoradiation for locally advanced cervical cancer.

BACKGROUND: We investigated the feasibility of dose-dense neoadjuvant chemotherapy (NACT) with paclitaxel and carboplatin before radical chemoradiation (CRT) and assessed the response rate to such a regimen. METHODS: CxII is a single-arm phase II trial of 46 patients, with locally advanced cervical cancer (stage Ib2-IVa). Patients received dose-dense carboplatin (AUC2) and paclitaxel (80 mg m⁻²) weekly for six cycles followed by CRT (40 mg m⁻² of weekly cisplatin, 50.4 Gy, 28 fractions plus brachytherapy). The primary end point was response rate 12 weeks post-CRT. RESULTS: Baseline characteristics were: median age at diagnosis 43 years; 72% squamous, 22% adenocarcinoma and 7% adenosquamous histologies; FIGO stage IB2 (11%), II (50%), III (33%), IV (7%). Complete or partial response rate was 70% (95% CI: 54-82) post-NACT and 85% (95% CI: 71-94) post-CRT. The median follow-up was 39.1 months. Overall and progression-free survivals at 3 years were 67% (95% CI: 51-79) and 68% (95% CI: 51-79), respectively. Grade 3/4 toxicities were 20% during NACT (11% haematological, 9% non-haematological) and 52% during CRT (haematological: 41%, non-haematological: 22%). CONCLUSION: A good response rate is achieved by dose-dense weekly NACT with carboplatin and paclitaxel followed by radical CRT. This treatment regimen is feasible as evidenced by the acceptable toxicity of NACT and by the high compliance to radiotherapy (98%).

Three-dimensional MRI of the male urethrae with implanted artificial sphincters: initial results.

The aim of this study was to develop a method for simultaneous 3D visualization of a new type of artificial urethral sphincter (AUS) and adjacent urinary structures. Serial MR tomograms were acquired from seven men after AUS implantation. 3D reconstruction was performed by thresholding original (positive) and inverted (negative) image intensity and by subsequently fusing positive and negative images. Results show that the bladder, cuff and balloons of the AUS of originally high intensity were imaged in 3D by thresholding the positive datasets. The urethrae and corpora cavernosa penis of originally low intensity were displayed in 3D by thresholding the negative datasets. Fusion of the positive and negative datasets allowed simultaneous visualization of the AUS complex and adjacent urinary structures. All the structures of interest were also clearly seen by interactive multiplanar reformatting. Coronal tomographic datasets provided better 3D and reformatted 2D images than sagittal and transverse datasets. This technique offers a simple means for evaluating the complex urethral anatomy and the AUS, and has potential for improved 3D visualization of many other complex morphological and pathological conditions.

Cerebral proton magnetic resonance spectroscopy in asymptomatic HIV infection.

OBJECTIVE: To determine whether proton magnetic resonance spectroscopy (MRS) demonstrates central nervous system abnormalities in asymptomatic HIV-1-infected individuals. DESIGN: Both prospective and retrospective cross-sectional analyses of MRS in asymptomatic HIV-infected individuals. SETTING: Two specialists HIV/AIDS outpatient facilities in London. PARTICIPANTS: Eighty-four HIV-1 seropositive asymptomatic men; 29 HIV-1 antibody-negative homosexual men at high-risk for HIV infection and 48 HIV-1 antibody-negative men at low-risk for HIV infection as controls. MAIN OUTCOME MEASURES: Single voxel, gradient-localized proton MRS performed at 1.5 T with 135 msec echo-time and 1,600 msec repeat-time in an 8 ml volume of interest positioned in the parieto-occipital white matter. Spectroscopic results were expressed as ratios between the areas under the N-acetyl (NA), creatine (Cr) and choline (Cho) resonance peaks. RESULTS: There were no differences between those controls at high and those at low-risk for HIV infection. Comparing the combined control groups with the asymptomatic seropositive patients there were statistically significant differences in NA/Cho, NA/Cr (both P < 0.05) and NA/(NA + Cho + Cr) (P < 0.01). CONCLUSION: Abnormalities in cerebral biochemistry may be demonstrated by proton MRS during asymptomatic HIV-1 infection.

A multicenter proton magnetic resonance spectroscopy study of neurological complications of AIDS.

Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.

MR angiographic diagnosis of cerebral venous sinus thrombosis following allogeneic bone marrow transplantation.

Allogeneic bone marrow transplantation is frequently associated with neurological complications, particularly intracerebral bleeds and infections. Cerebral venous sinus thrombosis has only rarely been reported following allogeneic transplants. We report three cases of cortical venous thrombosis following allografting for acute lymphoblastic leukaemia. Two patients received marrow from HLA-identical siblings and one from an unrelated donor. Two of the patients presented with grand mal seizures and one presented with a headache. No neurological abnormalities were found upon clinical examination and lumbar puncture was normal in all three cases. In two of the patients computed tomography (CT) of the brain was normal and in the third showed non-specific abnormalities. Magnetic resonance imaging (MRI) with MR angiography (MRA) demonstrated cerebral venous sinus thrombosis in all three patients. In conclusion, cerebral venous sinus thrombosis should be considered in the differential diagnosis when neurological symptoms occur following allogeneic bone marrow transplantation. We therefore advocate the use of MRA for unexplained neurological symptoms post-allograft since without it cerebral venous sinus thrombosis may easily be missed.

Localized cerebral proton MR spectroscopy in HIV infection and AIDS.

PURPOSE: To document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection. METHOD: We studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects. RESULTS: Reduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03). CONCLUSIONS: By clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease.

Breast surgery after neoadjuvant treatment. Is it necessary?

The optimum management of women with advanced loco-regional breast cancer (T3-4, N1-2) is controversial. Neoadjuvant therapy in the form of chemotherapy and or radiotherapy is popular and results in an encouraging local response in over 70% of patients. However, should subsequent surgery (either mastectomy or breast conservation treatment) be undertaken in women who respond? We present a prospective evaluation of 15 patients with T3-4, N1-2 tumours (including 1 bilateral cancer) who underwent mastectomy after achieving a complete clinical response to neoadjuvant treatment. All patients had 6 cycles of chemotherapy and 10 also received 50 Gy radiotherapy. In addition to clinical examination, the response to neoadjuvant treatment was assessed by mammography (in all cases) and by magnetic resonance imaging (MR) (in eight patients). Careful histopathological assessment of the breast was undertaken to determine the extent of residual disease. In all patients histological malignancy was recognized within the breast. The size varied from 0.6 to 6.5 cm in maximum diameter with three grade I, eight grade II and five grade III tumours. Axillary lymph nodes were positive in seven patients. In conclusion, surgery is indicated for control of residual disease in locally advanced breast cancer regardless of the response to neoadjuvant treatment. Our preliminary observations suggest a potential role for breast MR in defining the extent of residual disease which may aid in the planning of surgery.

Impact of vessel distortion on transcranial Doppler velocity measurements: correlation with magnetic resonance imaging.

Because transcranial Doppler ultrasound is a blind procedure, it is not possible to routinely correct for insonation angle errors, which are presumed to be small. In anatomically normal brains this is a valid assumption; however, in some patients with distorted vascular anatomy (as in hydrocephalus) a small insonation angle cannot be assumed, and measurements of flow velocity may be misleadingly low. The orientation of the middle cerebral arteries was studied on magnetic resonance images of 17 control patients and three patients with hydrocephalus, and estimates of insonation angle errors in velocity measurements were made. When asymmetrical vessel distortion is present, relative flow to each hemisphere may not be accurately reflected in the measured velocities. Under these circumstances, the resistivity index may be a more reliable hemodynamic parameter.

Cerebral volumes and spectroscopic proton metabolites on MR: is sex important?

One of the factors that may influence the selection of appropriate controls for MR studies of the brain is gender. This study compared calculated intracranial volumes and proton spectroscopic metabolite ratios obtained from male and female volunteers. Thirty-two males (mean age = 36; range = 30-53 yr) and 19 females (mean age = 39; range = 26-53 yr) underwent investigation at 1.5T. Brain, cerebrospinal fluid (CSF), and intracranial (ICV = brain + CSF) volumes were measured by the CLASS technique on data acquired using an axial dual spin-echo imaging sequence (TE = 20/90 ms, TR = 3500 ms). Proton spectra (TE = 135 ms, TR = 1600 ms) were acquired from an 8 ml cubic region placed in parieto-occipital white matter. The mean male and female brain, CSF and ICV were significantly different (p < .005). However, the mean CSF/ICV ratios of the two groups were not significantly different. The N-acetyl/choline and choline/creatine metabolite ratios of the two groups were significantly different (p < .05). When comparing proton metabolite ratios and absolute brain volumes between groups, gender is an important factor. CSF/ ICV ratios do not appear to depend on gender.

Short echo time proton spectroscopy of the brain in HIV infection/AIDS.

Short echo time proton spectra have been acquired from the brains of 30 male homosexual Acquired Immunodeficiency Syndrome (AIDS) patients and 12 age-matched control subjects on a 1.5 T MR system. The acquisition protocol used stimulated acquisition voxel localisation with a voxel size of 8 ml and repeat, echo, and mixing times of 5000, 20, and 30 ms, respectively. A single 25.6-ms Gaussian water suppression pulse was used with 128 spectral acquisitions and the data were eddy current corrected using a water reference. Baseline-corrected spectra were nonlinearly least squares fitted to a model function consisting of Gaussian functions representing the major metabolites reported in short echo proton spectra. Results indicate that the N-acetyl/creatine (NA/Cr) ratio is significantly reduced by 20% in AIDS patients [NA/Cr = 1.91 (0.51)] compared to control subjects [NA/Cr = 2.37 (0.25)] at short echo times.

Proton spectroscopy in HIV infection: relaxation times of cerebral metabolites.

In vivo proton spectroscopy has demonstrated abnormalities in the cerebral metabolite ratios from subjects with acquired immunodeficiency syndrome (AIDS). Some of the sequences employed are subject to T1 or T2 weighting, which may affect spectroscopic interpretation. The relaxation times of choline (Cho), creatine (Cr), and N-acetyl (NA) resonances have been estimated at 1.5 T in 21 patients infected with the human immunodeficiency virus (HIV) and 8 controls using gradient localised, spin-echo spectroscopic sequences of varying echo and repetition times. A statistically significant increase in the T2 of NA was found in the HIV seropositive patients who had diffuse abnormalities on MR imaging consistent with HIV encephalopathy (493 +/- 199 ms) when compared to controls (292 +/- 118 ms; p < .05). No other statistically significant differences were found in the relaxation times between patients and control subjects. These results demonstrate that signals from the NA resonance obtained using long echo time sequences in subjects who are HIV seropositive are not solely indicative of metabolite concentration.

The measurement of R2, R2* and R2' in HIV-infected patients using the prime sequence as a measure of brain iron deposition.

Brain iron deposition was assessed at 1.5 T in the caudate nucleus, globus pallidus and frontal and parieto-occipital white matter in 28 human immunodeficiency virus (HIV)-infected patients and 15 control subjects with a new Partially Refocussed Interleaved Multi-Echo sequence by measuring 1/T2, 1/T2* and 1/T2' (i.e., R2, R2* and R2'). There were significant differences in the R2 and R2* of the caudate nucleus (p < 0.0001 and p < 0.05) and the R2, R2* and R2' of the globus pallidus (p < 0.01, p < 0.005 and p < 0.05) in HIV-infected patients compared to control subjects. There was a trend for higher values of R2, R2* and R2' in the globus pallidus and caudate nucleus in HIV-infected patients with later stage HIV disease. These results suggest that there is greater iron deposition in the basal ganglia of HIV-infected patients compared with control subjects, with a predilection for the globus pallidus. The relationship between iron deposition in the brain and various parameters of severity of HIV infection remains uncertain.

Cerebral magnetic resonance relaxometry in HIV infection.

A prospective, cross-sectional study was designed to determine the magnetic resonance relaxation times of cerebral white matter in human immunodeficiency virus (HIV) infected individuals. T1 and T2 were estimated at 1.5 T using four-point methods. Seventy-five HIV-1 seropositive subjects, 48 seronegative blood donors, and 17 seronegative homosexual men were studied. Associations between relaxometry and clinical classification, neurological status, immunological status, and qualitative MRI were investigated. Statistically significant differences in white matter T1 relaxation time were found comparing low-risk control and AIDS groups (p < .005), seropositive subjects with neurological signs and those without (p < .005), and subjects with low (CD4 < or = 200 x 10(6)/l) and high (CD4 > 200 x 10(6)/1) CD4 cell counts (p < .05). These findings add to the body of information that reveals no HIV-related change in the brain before the onset of symptomatic immunosuppression and go someway to validating the previous visually rated, qualitative findings. Statistically significant difference in white matter T2 relaxation time were also found comparing the two control groups (p < .005) highlighting the need for appropriate controls.

Ascending lower-limb phlebography: a comparative study of Hexabrix 320, iohexol 300 and iohexol 240.

A prospective, randomised study on 60 legs in 45 patients examined by ascending lower-limb phlebography was conducted to compare Hexabrix 320 (May and Baker Ltd), iohexol 300 and iohexol 240. The quality of opacification of the veins, side-effects, cost and amount of contrast agent used were compared. All three agents produced adequate examinations. Iohexol 300 was preferred for its denser opacification. Iohexol 240 was associated with the lowest incidence of side-effects and Hexabrix 320 cost the least per examination.

Ultrashort echo time (UTE) MRI of the spine in thalassaemia.

Back pain is common in adult patients with homozygous thalassaemia, and degenerative disc disease is increasingly recognised as a cause. Ultrashort echo time (UTE) pulse sequences, which are sensitive to the presence of short T(2) relaxation components in tissue produced by iron deposition and other processes, were used to examine the lower thoracic and lumbar spine in symptomatic patients with beta-thalassaemia major or intermedia. Three patients were studied with fat suppressed as well as both fat suppressed and long T(2) suppressed UTE (TE=0.08 ms) pulse sequences. Conventional 2D Fourier transformation T(1) and T(2) weighted scans were also performed for comparison. Normal controls showed narrow high signal areas in the region of the end-plate and annulus fibrosus. Patients showed hyperintense bands adjacent to the vertebral end plate in lower thoracic and lumbar spine discs using a UTE sequence with both long T(2) component and fat suppression. The extent of the changes was most marked in the patient with the most severe degenerative change. In the patient with minimal disease, findings of this type were present in discs which did not show evidence of degeneration with conventional MR imaging. High signal changes of a type previously not described were observed in each patient. The effect may be due to organic iron entering the disc and decreasing its T(1) and T(2), but susceptibility effects from iron in the vertebral bodies, fibrosis and other causes also need to be considered.

Sedation in children scanned with high-field magnetic resonance; the experience at the Hospital for Sick Children, Great Ormond Street.

Patient movement is the most common cause of image degradation when performing magnetic resonance scans in children. This is a particular problem scanning at high field, as noise levels of up to 90 dB may be reached. Movement can be reduced by adequate sedation. We present the results of two sedation protocols when scanning with a 1.5T Magnetom scanner. Optimal scan quality can be achieved in up to 85% of scans using Pethco combined with triclofos in children aged 1 month-2 years, and trimeprazine combined with papaveretum in children over 2 years. When heavy sedation is used, patient selection must be cautious, and there is a minimum acceptable level of monitoring including close physical observation, electrocardiographic and apnoea monitoring.