Ultrasound assessment of muscle mass and correlation with clinical outcomes in critically ill patients: a prospective observational study.

PURPOSE: Muscular atrophy implies structural and functional alterations related to muscular force production and movement. This condition has been reported to be the main reason for generalized muscle weakness; it reflects the severity of the disease and can have a profound impact on short- and long-term clinical outcomes. The purpose of this study was to determine whether muscle atrophy ultrasound parameters early predict muscle weakness, morbidity, or 28-days mortality. METHODS: This was a prospective, observational single center cohort study. Ultrasound was used to determine the cross-sectional area and muscle thickness of the rectus femoris on the first and third day of ICU stay. The main outcome was the incidence of significant muscle atrophy (≥ 10%). RESULTS: Ultrasound measurements were made in 31 patients, 58% (18/31) of which showed significant muscle atrophy. The relative loss of muscle mass per day was 1.78 at 5% per day. The presence of muscle atrophy presents increased risk for limb muscle weakness and handgrip weakness. The 28-days mortality rate was similar in both subgroups. CONCLUSION: The presence of muscle atrophy presents an increased clinical risk for the development of limb ICUAW and handgrip, although these observations were not statistically significant. The results could be used to plan future studies on this topic.

[Intensive care unit-acquired weakness-Diagnostic value of neuromuscular ultrasound]. / Intensive Care Unit-Acquired Weakness ­ diagnostischer Stellenwert des neuromuskulären Ultraschalls.

Intensive care unit-acquired weakness (ICUAW) is one of the most common neuromuscular complications in intensive care medicine. The clinical diagnosis and assessment of the severity using established diagnostic methods (e.g., clinical examination using the Medical Research Council Sum Score or electrophysiological examination) can be difficult or even impossible, especially in sedated, ventilated and delirious patients. Neuromuscular ultrasound (NMUS) has increasingly been investigated in ICUAW as an easy to use noninvasive and mostly patient compliance-independent diagnostic alternative. It has been shown that NMUS appears to be a promising tool to detect ICUAW, to assess the severity of muscular weakness and to monitor the clinical progression. Further studies are needed to standardize the methodology, to evaluate the training effort and to optimize outcome predication. The formulation of an interdisciplinary neurological and anesthesiological training curriculum is warranted to establish NMUS as a complementary diagnostic method of ICUAW in daily clinical practice.

Neuromuscular Ultrasound in Intensive Care Unit-Acquired Weakness: Current State and Future Directions.

Intensive care unit-acquired weakness (ICUAW) is one of the most common causes of muscle atrophy and functional disability in critically ill intensive care patients. Clinical examination, manual muscle strength testing and monitoring are frequently hampered by sedation, delirium and cognitive impairment. Many different attempts have been made to evaluate alternative compliance-independent methods, such as muscle biopsies, nerve conduction studies, electromyography and serum biomarkers. However, they are invasive, time-consuming and often require special expertise to perform, making them vastly impractical for daily intensive care medicine. Ultrasound is a broadly accepted, non-invasive, bedside-accessible diagnostic tool and well established in various clinical applications. Hereby, neuromuscular ultrasound (NMUS), in particular, has been proven to be of significant diagnostic value in many different neuromuscular diseases. In ICUAW, NMUS has been shown to detect and monitor alterations of muscles and nerves, and might help to predict patient outcome. This narrative review is focused on the recent scientific literature investigating NMUS in ICUAW and highlights the current state and future opportunities of this promising diagnostic tool.

Can MR neurography of the common peroneal nerve predict a residual motor deficit in patients with foot drop?

OBJECTIVE: To determine if MR neurography of the common peroneal nerve (CPN) predicts a residual motor deficit at 12-month clinical follow-up in patients presenting with foot drop. MATERIALS AND METHODS: A retrospective search for MR neurography cases evaluating the CPN at the knee was performed. Patients were included if they had electrodiagnostic testing (EDX) within 3 months of imaging, ankle and/or forefoot dorsiflexion weakness at presentation, and at least 12-month follow-up. Two radiologists individually evaluated nerve size (enlarged/normal), nerve signal (T2 hyperintense/normal), muscle signal (T2 hyperintense/normal), muscle bulk (normal/Goutallier 1/Goutallier > 1), and nerve and muscle enhancement. Discrepancies were resolved via consensus review. Multivariable logistical regression was used to evaluate for association between each imaging finding and a residual motor deficit at 12-month follow-up. RESULTS: Twenty-three 3 T MRIs in 22 patients (1 bilateral, mean age 52 years, 16 male) met inclusion criteria. Eighteen cases demonstrated common peroneal neuropathy on EDX, and median duration of symptoms was 5 months. Six cases demonstrated a residual motor deficit at 12-month follow-up. Fourteen cases underwent CPN decompression (1 bilateral) within 1 year of presentation. Three cases demonstrated Goutallier > 1 anterior compartment muscle bulk. Multivariable logistical regression did not show a statistically significant association between any of the imaging findings and a residual motor deficit at 12-month follow-up. CONCLUSION: MR neurography did not predict a residual motor deficit at 12-month follow-up in patients presenting with foot drop, though few patients demonstrated muscle atrophy in this study.

The possible predictive value of muscle ultrasound in the diagnosis of ICUAW in long-term critically ill patients.

PURPOSE: Intensive Care Unit acquired weakness (ICUAW) occurs commonly. Muscular ultrasonography allows visualization and classification of muscle characteristics. The aims of this study were to evaluate peripheral and respiratory muscles, their changes during long-term ICU stays, and the possible diagnostic predictive value of ICUAW as compared to the Medical Research Council strength score (MRC-SS). MATERIALS: 50 mechanically ventilated patients were enrolled. Within 48 h after ICU admission (T1), patients underwent muscular ultrasound (rectus femoris cross sectional area (RFCSA), pennation angle, diaphragm, and parasternal intercostal). All the same measures were repeated at days 3 (T3) and 7 (T7). Muscle strength assessment was performed using the MRC-SS. RESULTS: No significant differences were found regarding age, sex, weight, height, or BMI values, in those who developed ICUAW according to MRC-SS. The RF pennation angle, however, significantly changed between T7-T1 in patients who developed ICUAW and was. Found to be the best predictor of ICUAW. CONCLUSIONS: Quadriceps and respiratory muscles were altered within the first week of mechanical ventilation. The loss of pennation angle offers high diagnostic accuracy for ICUAW, allowing for an earlier diagnosis before patients became able to perform volitional tests.

Changes in muscle ultrasound for the diagnosis of intensive care unit acquired weakness in critically ill patients.

To test diagnostic accuracy of changes in thickness (TH) and cross-sectional area (CSA) of muscle ultrasound for diagnosis of intensive care unit acquired weakness (ICU-AW). Fully conscious patients were subjected to muscle ultrasonography including measuring the changes in TH and CSA of biceps brachii (BB) muscle, vastus intermedius (VI) muscle, and rectus femoris (RF) muscles over time. 37 patients underwent muscle ultrasonography on admission day, day 4, day 7, and day 10 after ICU admission, Among them, 24 were found to have ICW-AW. Changes in muscle TH and CSA of RF muscle on the right side showed remarkably higher ROC-AUC and the range was from 0.734 to 0.888. Changes in the TH of VI muscle had fair ROC-AUC values which were 0.785 on the left side and 0.779 on the right side on the 10th day after ICU admission. Additionally, Sequential Organ Failure Assessment (SOFA), Acute Physiology, and Chronic Health Evaluation II (APACHE II) scores also showed good discriminative power on the day of admission (ROC-AUC 0.886 and 0.767, respectively). Ultrasonography of changes in muscles, especially in the TH of VI muscle on both sides and CSA of RF muscle on the right side, presented good diagnostic accuracy. However, SOFA and APACHE II scores are better options for early ICU-AW prediction due to their simplicity and time efficiency.

Radiographs assessment of changes in the psoas muscle at L4-L5 level after single-level lateral lumbar interbody fusion in patients with postoperative motor weakness.

The purposes of this study were (1) to investigate postoperative changes in cross-sectional area (CSA) and signal intensity (SI) of the psoas muscle (PS) using magnetic resonance imaging (MRI) and (2) to compare the CSA and SI of the PS between patients with and without motor weakness after single-level lateral lumbar interbody fusion (LLIF) at level L4-L5. Sixty patients were divided into two groups-those with postoperative motor weakness and those without-and the two groups were compared. Baseline demographics and clinical characteristics, such as operation time and blood loss, length of hospital stay, and postoperative complications, were recorded. The CSA and SI of the PS were obtained from the MRI regions of interest defined by manual tracing. Patients who developed motor weakness after surgery were significantly older (p = 0.040). The operation time (p = 0.868), LLIF operative time (p = 0.476), and estimated bleeding loss (p = 0.168) did not differ significantly between groups. In both groups, the CSA and SI of the left and right PS increased after surgery. The change in the CSA of the left PS was significantly higher in patients with weakness (247.6 ± 155.2 mm2) than without weakness (152.2 ± 133.1 mm2) (p = 0.036). The change in SI of the left PS did not differ between the two groups (p = 0.530). To prevent postoperative motor weakness regardless of the operation time, surgeons should be aware of the potential for surgical invasive of the PS during LLIF in older people.

[A case of dropped head syndrome suspected due to Dipeptidyl peptidase (DPP)-4 inhibitor use].

There have been a few reports on Dipeptidyl peptidase (DPP)-4 inhibitor-induced dropped head syndrome. However, there has been no known report on temporal changes in MRI findings. The patient described here was a 63-year-old man who was prescribed oral sitagliptin (50 mg/day) in February 2019. He experienced a dropped head from mid-January 2020, and in early April that year, he was admitted to our hospital for further evaluation. Weakness of the cervical extensor muscles (MMT 3) was noted, and MRI findings showed that the posterior cervical muscle group was hyperintense on short inversion time inversion recovery (STIR). We suspected sitagliptin to be the cause of his dropped head and discontinued it. On the 10th day of admission, his posture improved to the median position. One month after discontinuation of sitagliptin, MRI findings showed an improvement in the STIR hyperintensity of the posterior cervical muscle. In conclusion, if the initiation of a DPP-4 inhibitor results in dropped head syndrome, discontinuation of the drug should be considered.

Desminopathy presenting as late onset bilateral facial weakness, with diagnosis supported by lower limb MRI.

A 63 year old male presented with a 20 year history of facial weakness and several years of nasal regurgitation and dysphonia. Examination revealed bilateral facial weakness with nasal speech. Serum creatine kinase was 918 U/L. Neurophysiological studies suggested a myopathy and biopsy of the left vastus lateralis showed serpentine basophilic inclusions in the sarcoplasm and strong oxidative enzyme activity suggesting mitochondria accumulation. The muscle MRI showed selective fatty replacement within semitendinosus, gastrocnemius and soleus indicative of a desminopathy. A heterozygous missense variant c.17C>G (p.Ser6Trp) was identified within DES, predicted to be pathogenic in silico and previously described in a family with distal limb weakness. There are no previous case reports of desminopathy presenting with facial weakness, to our knowledge. Diagnosis was suggested following myoimaging of clinically unaffected muscles. Our study highlights the importance of muscle MRI in the diagnostic evaluation of muscle disease and further expands the known phenotypic heterogeneity of desminopathies.

MRI monitoring of macaque monkeys in neuroscience: Case studies, resource and normative data comparisons.

Information from Magnetic Resonance Imaging (MRI) is useful for diagnosis and treatment management of human neurological patients. MRI monitoring might also prove useful for non-human animals involved in neuroscience research provided that MRI is available and feasible and that there are no MRI contra-indications precluding scanning. However, MRI monitoring is not established in macaques and a resource is urgently needed that could grow with scientific community contributions. Here we show the utility and potential benefits of MRI-based monitoring in a few diverse cases with macaque monkeys. We also establish a PRIMatE MRI Monitoring (PRIME-MRM) resource within the PRIMatE Data Exchange (PRIME-DE) and quantitatively compare the cases to normative information drawn from MRI data from typical macaques in PRIME-DE. In the cases, the monkeys presented with no or mild/moderate clinical signs, were well otherwise and MRI scanning did not present a significant increase in welfare impact. Therefore, they were identified as suitable candidates for clinical investigation, MRI-based monitoring and treatment. For each case, we show MRI quantification of internal controls in relation to treatment steps and comparisons with normative data in typical monkeys drawn from PRIME-DE. We found that MRI assists in precise and early diagnosis of cerebral events and can be useful for visualising, treating and quantifying treatment response. The scientific community could now grow the PRIME-MRM resource with other cases and larger samples to further assess and increase the evidence base on the benefits of MRI monitoring of primates, complementing the animals' clinical monitoring and treatment regime.

Spinal adhesive arachnoiditis: three case reports and review of literature.

Spinal adhesive arachnoiditis is a rare pathology involving pia mater of the spinal cord and nerve roots. It can potentially lead to disability-many patients end up wheelchair-bound due to subsequent paraparesis. It is an infrequent but possible cause of lower extremities weakness in patients with a history of spinal surgery, epidural anaesthesia, myelography or spinal tumors. Three patients, one male and two females, admitted to our unit due to paraparesis presented at least one of the above mentioned risk factors. Each of them had a severe course of illness-progressive paresis of lower extremities. All above cases were diagnosed with spinal adhesive arachnoiditis confirmed with Magnetic Resonance Imaging (MRI) scan-the most sensitive and specific diagnostic tool. Despite conservative treatment and intensive rehabilitation none of the presented patients preserved the ability to mobilise independently. Considering spinal adhesive arachnoiditis in patients with paraparesis and history of typical risk factors should be included in clinical diagnostic procedure.

Cerebellar-limbic neurocircuit is the novel biosignature of physio-cognitive decline syndrome.

Both physical and cognitive deficits occur in the aging process. We operationally defined the phenomenon as physio-cognitive decline syndrome (PCDS) and aimed to decipher its corresponding neuroanatomy patterns and neurocircuit. High resolution 3T brain magnetic resonance imaging (MRI) images from a community-dwelling longitudinal aging cohort were analysed. PCDS was defined as weakness (handgrip strength) and/or slowness (gait speed) concomitant with impairment in any cognitive domain (defined by 1.5 standard deviation below age, sex-matched norms), but without dementia or disability. Among 1196 eligible ≥ 50-year-old (62±9 years, 47.6%men) subjects, 15.9% had PCDS. Compared to the other participants, individuals with PCDS had significantly lower gray-matter volume (GMV) in the bilateral amygdala and thalamus, right hippocampus, right temporo-occipital cortex, and left cerebellum VI and V regions. The regions of reduced GMV in people with PCDS were similar between the middle-aged and older adults; whereas larger clusters with more extensive GMV-depleted regions were observed in ≥65-year-olds with PCDS. Diffusion-weighted tractography showed disrupted hippocampus-amygdala-cerebellum connections in subjects with PCDS. The neuroanatomic characteristics revealed by this study provide evidence for pathophysiological processes associated with concomitant physio-cognitive decline in the elderly. This neurocircuit might constitute a target for future preventive interventions.

Unilateral-dominant reduction in muscle volume in female knee osteoarthritis patients: computed tomography-based analysis of bilateral sides.

BACKGROUND: Muscle weakness is associated with osteoarthritis pathology. A recent study demonstrated that measuring muscle volume using computed tomography (CT)-based analysis and comparing bilateral muscles in the same patient allowed for accurate evaluation of muscle volume in unilateral hip osteoarthritis (OA) patients. Here, we evaluated muscle volume using CT-based analysis and compared bilateral muscles in knee OA (KOA) patients. METHODS: CT images were obtained from 35 female radiographic KOA patients the day prior to total knee replacement surgery. Muscle volume (MV) was semi-automatically analyzed. Knee extension muscle strength (MS) was determined using a hand-held dynamometer. The severity of KOA patients' clinical symptoms was examined using four domains of the Japanese Orthopedic Association (JOA) score. We compared the difference in MS (ΔMS) and MV (ΔMV) between the operated side (OS), which exhibited severe radiographic OA or severe pain, and the contralateral side (CS). RESULTS: JOA score was significantly lower in the OS than CS. MV and MS were also significantly lower in the OS than CS. There was no correlation between MV and MS or between MV and MS as a percentage of body weight on either side. However, ΔMV was positively correlated with ΔMS and pain on walking in the JOA. CONCLUSIONS: We evaluated MV and MS using bilateral CT images of the legs of KOA patients. A reduction in MV was observed on the OS, and was correlated with a reduction in MS and pain on walking. Bilateral CT image analysis may be useful for evaluating the relationship between OA pathology and muscle atrophy.

Diabetic Lumbosacral Radiculoplexus Neuropathy (Diabetic Amyotrophy).

Diabetic lumbosacral radiculoplexus neuropathy, also known as diabetic amyotrophy, has a characteristic course of sudden onset of unilateral pain in the thigh and hip, which may spread to the other side in weeks to months and proceeds with progressive lower extremity weakness, often resulting in the inability to walk unassisted. The syndrome is typically monophasic, and most patients will recover at least to some degree. Less typical features include lack of pain, distal predominant weakness, absence of diabetes, and upper extremity involvement. This article provides a series of interesting cases to highlight the diagnostic challenges and discusses management decision making.

Two Cases of Posterior Cerebral Artery P2 Segment Occlusion with Motor Weakness Improved by Acute Mechanical Thrombectomy.

BACKGROUND: Clinical evidence to support the use of mechanical thrombectomy (MT) for posterior cerebral artery P2 segment occlusion (P2O) has not been established, and hemiplegia due to P2O improved by MT to our knowledge has not yet been reported. We report 2 cases of P2O with hemiplegia improved by MT. CASE DESCRIPTION: In case 1, a 68-year-old man was admitted with right hemiplegia and dysesthesia (National Institutes of Health Stroke Scale score 14). Head magnetic resonance imaging showed acute ischemia in the left inferolateral thalamus and posterior limb of the internal capsule. Angiography showed left P2O, which was recanalized after MT. Hemiplegia improved immediately following recanalization, and modified Rankin Scale score at discharge was 0. In case 2, a 69-year-old man was admitted with left hemiplegia and dysesthesia (National Institutes of Health Stroke Scale score 8). Head magnetic resonance imaging showed acute ischemia in the right inferolateral thalamus and posterior limb of the internal capsule. Angiography showed right P2O, which was recanalized after MT, as in case 1. His symptoms resolved completely. CONCLUSIONS: P2O may cause severe motor deficit. In such cases, MT may contribute to safely improving patients' deficits.