Imaging counterpart of postural instability and vertical ocular dysfunction in patients with PSP: A multimodal MRI study

INTRODUCTION

We investigated the imaging counterpart of two functional domains (ocular motor dysfunction and postural instability) in progressive supranuclear palsy (PSP) patients classified according to the new clinical diagnostic criteria.

METHODS

Forty-eight patients with probable PSP-Richardson's syndrome (PSP-RS), 30 with probable PSP-parkinsonism (PSP-P), 37 with Parkinson's disease (PD), and 38 controls were enrolled. For each functional domain, PSP patients were stratified by two certainty levels: vertical supranuclear gaze palsy (O1) and slowness of vertical saccades (O2) for ocular motor dysfunction; early unprovoked falls and tendency to fall on the pull-test for postural instability. Voxel-based morphometry (VBM), whole-brain fractional anisotropy (FA) and MR planimetric measurements were analysed and compared across patient groups.

RESULTS

O1 was present in 64%, and O2 in 36% of all PSP patients. All PSP-RS patients showed early unprovoked falls. TBSS whole-brain analysis revealed that superior cerebellar peduncles (SCPs) were the only structures with significantly lower FA values in PSP-RS compared with PSP-P patients. PSP/O1 patients had lower FA values in midbrain than PSP/O2 patients. By contrast, VBM revealed no differences in grey matter volume between PSP patient groups. MR Planimetric measurements confirmed atrophy of midbrain and SCPs, in line with DTI findings.

CONCLUSIONS

Our study demonstrates that SCPs were significantly more damaged in patients with PSP-RS in comparison with PSP-P patients, thus suggesting the role of SCPs in developing postural instability. Midbrain damage was less severe in O2 than in O1 patients, suggesting that the degree of vertical ocular dysfunction reflects the severity of midbrain atrophy.

Refining initial diagnosis of Parkinson's disease after follow-up: A 4-year prospective clinical and magnetic resonance imaging study

Background

No prospective study of patients with Parkinson's disease (PD) has investigated the appearance of vertical gaze abnormalities, a feature suggestive of progressive supranuclear palsy (PSP).

Objective

To identify, within a cohort of patients with an initial diagnosis of PD, those who developed vertical gaze abnormalities during a 4‐year follow‐up, and to investigate the performance of new imaging biomarkers in predicting vertical gaze abnormalities.

Methods

A total of 110 patients initially classified as PD and 74 controls were enrolled. All patients underwent clinical assessment at baseline and every year up to the end of the follow‐up. The pons/midbrain area ratio 2.0 and the Magnetic Resonance Parkinsonism Index 2.0 were calculated.

Results

After 4‐year follow‐up, 100 of 110 patients maintained the diagnosis of PD, whereas 10 PD patients (9.1%) developed vertical gaze abnormalities, suggesting an alternative diagnosis of PSP‐parkinsonism. At baseline, the Magnetic Resonance Parkinsonism Index 2.0 was the most accurate biomarker in differentiating PD patients who developed vertical gaze abnormalities from those who maintained an initial diagnosis of PD. At the end of follow‐up, both of these biomarkers accurately distinguished PSP‐parkinsonism from PD.

Conclusions

Our results demonstrate that a number of patients with an initial diagnosis of PD developed vertical gaze abnormalities during a 4‐year follow‐up, and the diagnosis was changed from PD to PSP‐parkinsonism. In PD patients, baseline Magnetic Resonance Parkinsonism Index 2.0 showed the best performance in predicting the clinical evolution toward a PSP‐parkinsonism phenotype, enabling PSP‐parkinsonism patients to be identified at the earliest stage of the disease for promising disease‐modifying therapies. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

[Magnetic resonance findings in chronic osteomyelitis fistula]

INTRODUCTION

Osteomyelitis is a common inflammatory process caused by an infection which is usually from gram-positive germs. Acute, subacute and chronic forms can be distinguished both clinically and radiographically, each of them presenting different patterns but which are not always easy to recognize. Besides clinical-laboratory data, imaging methods are also useful to make the diagnosis; in chronic forms, MRI has higher sensitivity in recognizing the active foci and the presence of sinus tracts than the other techniques.

MATERIAL AND METHODS

We examined nine patients with suspected chronic osteomyelitis with a sinus tract, all of them submitted to radiographic and MR examinations. MRI was performed with a .5 T magnet using a surface coil for joint studies; T1-weighted SE (TR 300-500, TE 20), T2-weighted GE (TR 500-700, TE 20, FA 35 degrees) and FIR sequences with fat suppression (TR 3000, TE 20, TI 100) were performed on the axial, sagittal and coronal planes. Three patients underwent CT too.

RESULTS

Radiography showed the osteostructural changes as osteolytic and osteosclerotic areas. CT depicted not only the changes seen radiographically, but also increased bone marrow density. MRI demonstrated active foci of bone marrow appearing as low-intensity areas in T1, with increased intensity in T2 GE and fat-suppressed FIR images; it also depicted the sinus tracts as areas of decreased signal on T1 and of increased signal on FIR images.

CONCLUSIONS

Based on our experience and in agreement with the literature data, we believe that MRI is more useful to diagnose the active foci of bone marrow and the sinus tracts in chronic osteomyelitis, especially with T1-weighted SE and fat-suppressed FIR sequences.

["Occult" posttraumatic lesions of the knee: can magnetic resonance substitute for diagnostic arthroscopy?]

PURPOSE

We investigated the actual role of MRI versus arthroscopy in the detection and characterization of occult bone and/or cartilage injuries in patients with previous musculoskeletal trauma of the knee, pain and severe functional impairment. Occult post-traumatic osteochondral injuries of the knee are trauma-related bone and/or cartilage damage missed at plain radiography.

MATERIAL AND METHODS

We retrospectively selected 70 patients (men:women = 7:3; age range: 35 +/- 7 years) with a history of acute musculoskeletal trauma, negative conventional radiographs, pain and limited joint movements. All patients were submitted to conventional radiography, arthroscopy and MRI, the latter with 0.5 T units and T1-weighted SE. T2-weighted GE and FIR sequences with fat suppression.

RESULTS AND DISCUSSION

We identified three types of occult post-traumatic injuries by morpho-topographic and signal intensity patterns: bone bruises (no. 25), subchondral (no. 33) and osteochondral (no. 35) injuries. Arthroscopy depicted 45 osteochondral and 19 chondral injuries. A bone bruise was defined as a typical subcortical area of signal loss, with various shapes, on T1-weighted images and of increased signal intensity on T2-weighted and FIR images. The cortical bone and articular cartilage were normal in all cases, while osteochondral injuries exhibited associated bone and cartilage damage with the same abnormal MR signal intensity. Sprain was the mechanism of injury in 52 cases, bruise in 12 and stress in 6. In 52 sprains (30 in valgus), the injury site was the lateral compartment in 92.3% of cases (100% in valgus), associated with meniscal damage in 73% of cases (90% in valgus) and with ligament injury in 90.4% (100% in valgus). In 12 bruises, the injury site was the lateral compartment in 58.3% of cases, the knee cap in 25% and the medial compartment in 16.7%; meniscal damage was associated in 25% of cases and ligament damage in 8.3%. In 6 stress injuries, the injury site was localized in the medial tibial condyle in 80% of cases, while meniscal and ligament tears were absent.

CONCLUSIONS

After comparing MR with arthroscopic findings and reviewing the available literature, we conclude that arthroscopy permits the direct visualization of even fine articular surface changes but does not depict the subchondral bone, the most frequent site of injury detected with MRI. MRI was a very useful tool in the detection and characterization of the different types of occult bone and/or cartilage injuries and showed a statistically significant correlation between site and distribution of bone and cartilage injuries and between internal damage and trauma mechanisms. Therefore, we believe that MRI can help avoid diagnostic arthroscopy in the patients with a history of post-traumatic pain, acute articular blocks and negative radiographic findings.

[Transient osteoporosis of the hip in magnetic resonance imaging]

This study was aimed at assessing the MR patterns of transient osteoporosis of the hip and, consequently, the role of MRI in the diagnosis and follow-up of this condition. Even though this condition was originally observed in pregnant women, young or middle-aged men are most frequently affected. There is a spontaneous onset of pain, usually progressing over several weeks. The patients have no risk factors for osteonecrosis; they may have a history of minor trauma and there is a possible relationship to the third trimester of pregnancy. Laboratory values are negative. Pain may be severe enough to cause the patient to limp and to impair joint function. The possible causes of transient osteoporosis have been debated by many authors and include trauma, synovitis, neurovascular dysfunction and transient or reversible ischemia. Transient osteoporosis is a self-limiting disease which does not require surgical treatment. The differential diagnosis of transient osteoporosis of the hip is very important because this condition may simulate cancer, septic arthritis, osteomyelitis or avascular necrosis. We report the initial and follow-up features of transient osteoporosis of the hip on the MR images of 6 patients (M/F = 5/1; age: 37-49 years, mean: 41.8 years). The right side was involved in 3 patients, the left side in 2 patients. The patient with bilateral transient osteoporosis was a woman in the 3rd trimester of pregnancy. In all patients, MRI was performed with an 0.5 T MR unit. The MR changes in our 6 patients were rather uniform and included heterogeneous decrease in the signal intensity of the affected bone marrow on T1-weighted images and increased signal intensity on T2-weighted and STIR images, with no evidence of focal lesions. This pattern is known as the "bone marrow edema" (BME) pattern. All the patients received conservative treatment. The clinical symptoms and the MR abnormalities regressed completely within 6-10 months, with no late sequelae. To conclude, this follow-up MR study demonstrates the transient, reversible character of transient osteoporosis of the hip. Until the natural history of the BME pattern is better understood, we suggest a conservative management of this condition, especially in the patients with no risk factors for osteonecrosis. Radiographic and MR follow-up is recommended.

[Magnetic resonance aspects of the bone marrow in aplastic anemia at the onset and in the follow-up after transplant]

Aplastic anemia is a rare hematologic disorder characterized by hypocellular fatty marrow. Aplastic anemia is diagnosed on the basis of laboratory tests and bone marrow biopsy findings. Biopsy is of fundamental importance for bone marrow assessment, though not representative of the rest of the marrow. Thanks to its exclusive capabilities in the direct visualization of bone marrow, MRI is a noninvasive and relatively rapid method for bone marrow study. The authors report their experience in 3 aplastic anemia patients examined also with MRI at presentation and after marrow transplantation. The dorsolumbar spine was studied with sagittal SE T1-weighted and STIR sequences, while pelvic bones were investigated only with SE T1-weighted sequences in all patients. Two of them were also examined with sagittal scans of the dorsolumbar spine using the chemical shift fat suppression technique. In all three patients, SE T1-weighted images at presentation showed fatty bone marrow infiltration, also confirmed on fat suppression images, and, after transplantation, progressive bone marrow repopulation, with the typical "band" pattern in vertebral marrow. Although MR specificity remains low in the demonstration of bone marrow disorders, the authors believe it to be a useful tool, after accurate clinical and laboratory exams, not only in the diagnosis but also and especially in the follow-up of these disorders.