Brain Magnetic Resonance Imaging (MRI) in Spinal Muscular Atrophy: A Scoping Review.

BACKGROUND: 5q Spinal Muscular Atrophy (SMA) is a prototypical lower motor neuron disorder. However, the characteristic early motor impairment raises the question on the scope of brain involvement with implications for further investigations on the brain as a potential therapeutic target. OBJECTIVE: To review changes across the SMA clinical spectrum reported on brain magnetic resonance imaging (MRI). METHODS: We conducted a scoping review of existing literature on PubMed and EMBASE. Two reviewers searched and retrieved relevant articles on magnetic resonance brain imaging in individuals with SMA censoring to April 2022. Full-text articles published in peer-reviewed journals or abstracts accepted to conferences in English and French were included. RESULTS: Twelve articles were identified describing a total of 39 patients [age range: 11 days to 41 years old, type 0 (n = 5), type 1 (n = 4), type 2 (n = 2), type 3 (n = 22), type 4 (n = 6)]. All reported structural changes and did not explore other MRI modalities. In individuals with infantile onset SMA, cortical and subcortical brain abnormalities in white matter, basal ganglia, thalamus, hippocampus, and high intensity areas around lateral ventricles and thalami were reported over time. In individuals with later-onset SMA, reduced cerebellar and lobular volume were observed as well as increased grey matter density in motor areas. CONCLUSIONS: Limited data on brain imaging in SMA highlights both cortical and subcortical involvement in SMA, supporting the hypothesis that changes are not restricted to lower motor neuron pathways. Further studies are needed to determine the extent and prevalence of structural and functional brain changes across SMA types.

Clinical Features of Female Carriers and Prodromal Male Patients With Spinal and Bulbar Muscular Atrophy.

BACKGROUND AND OBJECTIVES: To assess the clinical and electrophysiologic features of female carriers and early-stage male patients with spinal and bulbar muscular atrophy (SBMA) to elucidate the early pathophysiologic changes of the disease. METHODS: Female carriers, early-stage male patients with SBMA, and age-matched male and female healthy controls were recruited. The results of motor functional scales, motor unit number estimation, dual-energy X-ray absorptiometry, and peripheral blood tests were compared between female carriers and healthy female controls and between patients with SBMA and healthy male controls. EMG was also investigated in female carriers. RESULTS: We enrolled 21 female carriers and 11 early-stage male patients. Seventeen female and 14 male age-matched healthy controls were also enrolled. Female carriers experienced early-stage symptoms such as muscle cramps more frequently than healthy female controls. Decreased motor unit number estimation and EMG abnormalities including high amplitude or polyphasic potentials were observed in female carriers together with mild muscle weakness in neck flexion and a slow walking speed. Changes of muscle-related markers, including serum creatine kinase and dual-energy X-ray absorptiometry, were clearly detected in early-stage male patients with SBMA, but not in female carriers. DISCUSSION: The present study revealed that female carriers of SBMA manifest mild muscular weakness associated with changes in neurogenic biomarkers. Conversely, male patients showed neurogenic and myopathic changes even at the early stage. These results suggest a testosterone-independent neurodegenerative pathophysiology in female SBMA carriers.

Surgical treatment of spinal deformities in spinal muscular atrophy: a single-center experience from China.

PURPOSE: To report the clinical characteristics and surgical outcomes of scoliosis in patients with spinal muscular atrophy (SMA) from Mainland China. METHODS: Nineteen patients were retrospectively analyzed. Demographic, anthropometric and respiratory parameters were collected preoperatively. Surgical program was analyzed. Radiographic data were measured perioperatively. Motor status, ventilation support, sitting ability and respiratory symptoms were evaluated preoperatively and at final follow-up. RESULTS: Age at surgery was 17.08 (12.83, 20.08) years. More than 40% of patients were diagnosed with low weight. Pulmonary dysfunction was observed in all patients. All patients received posterior spinal fusion (PSF). Sacroiliac fixation with sacral-2 alar iliac technique was used in 16 patients. Major curve correction rate was 54.87 ± 16.14%. Pelvic obliquity correction rate was 63.84 ± 23.70%. T1-T12 height, space-available-for-lung ratio and thoracic transverse diameter were increased (p < 0.001). Percentage of patients capable of sitting independently increased from 26.32% preoperatively to 73.68% at final follow-up. Cumulative scores of sitting-related items in muscular dystrophy spine questionnaire improved from 19.11 ± 5.40 preoperatively to 26.21 ± 5.20 at final follow-up. Total scores of symptomatic domains in St. George's Respiratory Questionnaire decreased from 4 (2, 12) preoperatively to 1 (0, 3) at final follow-up. CONCLUSIONS: SMA patients in China always present severe scoliosis at late adolescence, accompanied with high proportion of low weight and pulmonary dysfunction. PSF is effective for the correction of scoliosis and pelvic obliquity and the improvement of thoracic morphology. Sitting ability and respiratory symptoms were improved postoperatively.

Cone-beam computed tomography guided nusinersen administrations in adult spinal muscular atrophy patients with challenging access: a single- center experience.

BACKGROUND: The challenging anatomic predispositions in adult patients with spinal muscular atrophy (SMA) preclude the conventional lumbar punctures. Consequently, an introduction of alternative method for intrathecal delivery of nusinersen is required. Cone-beam CT (CBCT) allows volumetric display of the area of interest, pre-procedural planning and real time needle guidance which results in accurate anatomic navigation. The aim of the study was to evaluate technical success, safety, and feasibility of CBCT lumbar intrathecal delivery of nusinersen in the adult SMA patients with challenging anatomical access. PATIENTS AND METHODS: Thirty-eight adult SMA patients were treated in our institution. Patients with challenging access were selected by multidisciplinary board for image guided administration of nusinersen either due to implantation of the posterior fusion instrumentation, severe scoliosis defined as Cobb's angle > 40º or body mass index over 35. Technical success, radiation exposure and occurrence of adverse events were assessed. RESULTS: Twenty patients were selected, and 108 CBCT-guided procedures were performed. Each patient underwent at least 4 administrations. Transforaminal approach was performed in 82% of patients. The technical success was 100%, with primary success of 93.5%. The median radiation effective dose of the administrations was 5 mSv, the mean value equalled 10 mSv. Only mild adverse events were reported in the study. CONCLUSIONS: CBCT-guided lumbar intrathecal administrations of nusinersen in an adult SMA population with challenging access was feasible and safe image guided method.

Magnetic resonance reveals mitochondrial dysfunction and muscle remodelling in spinal muscular atrophy.

Genetic therapy has changed the prognosis of hereditary proximal spinal muscular atrophy, although treatment efficacy has been variable. There is a clear need for deeper understanding of underlying causes of muscle weakness and exercise intolerance in patients with this disease to further optimize treatment strategies. Animal models suggest that in addition to motor neuron and associated musculature degeneration, intrinsic abnormalities of muscle itself including mitochondrial dysfunction contribute to the disease aetiology. To test this hypothesis in patients, we conducted the first in vivo clinical investigation of muscle bioenergetics. We recruited 15 patients and 15 healthy age and gender-matched control subjects in this cross-sectional clinico-radiological study. MRI and 31P magnetic resonance spectroscopy, the modality of choice to interrogate muscle energetics and phenotypic fibre-type makeup, was performed of the proximal arm musculature in combination with fatiguing arm-cycling exercise and blood lactate testing. We derived bioenergetic parameter estimates including: blood lactate, intramuscular pH and inorganic phosphate accumulation during exercise, and muscle dynamic recovery constants. A linear correlation was used to test for associations between muscle morphological and bioenergetic parameters and clinico-functional measures of muscle weakness. MRI showed significant atrophy of triceps but not biceps muscles in patients. Maximal voluntary contraction force normalized to muscle cross-sectional area for both arm muscles was 1.4-fold lower in patients than in controls, indicating altered intrinsic muscle properties other than atrophy contributed to muscle weakness in this cohort. In vivo31P magnetic resonance spectroscopy identified white-to-red remodelling of residual proximal arm musculature in patients on the basis of altered intramuscular inorganic phosphate accumulation during arm-cycling in red versus white and intermediate myofibres. Blood lactate rise during arm-cycling was blunted in patients and correlated with muscle weakness and phenotypic muscle makeup. Post-exercise metabolic recovery was slower in residual intramuscular white myofibres in patients demonstrating mitochondrial ATP synthetic dysfunction in this particular fibre type. This study provides the first in vivo evidence in patients that degeneration of motor neurons and associated musculature causing atrophy and muscle weakness in 5q spinal muscular atrophy type 3 and 4 is aggravated by disproportionate depletion of myofibres that contract fastest and strongest. Our finding of decreased mitochondrial ATP synthetic function selectively in residual white myofibres provides both a possible clue to understanding the apparent vulnerability of this particular fibre type in 5q spinal muscular atrophy types 3 and 4 as well as a new biomarker and target for therapy.

Hybrid versus total sublaminar wires in patients with spinal muscular atrophy undergoing scoliosis surgery.

BACKGROUND: Early versions of spinal muscular atrophy (SMA) scoliosis correction surgery often involved sublaminar devices. Recently, the utilization of pedicle screws has gained much popularity. Pedicle screws are generally believed to provide additional deformity correction, but pedicle size and rotational deformity limit their application in the thoracic spine, resulting in a hybrid construct involving pedicle screws and sublaminar wire. Studies of the efficacy of hybrid instrumentation in SMA scoliosis are often limited by the scarcity of the disease itself. In this study, we aimed to compare the surgical outcomes between hybrid constructs involving pedicle screws and sublaminar wire and sublaminar wire alone in patients with SMA scoliosis. METHODS: We retrospectively reviewed the clinical records and radiographic assessments of patients with SMA scoliosis who underwent corrective surgery between 1993 and 2017. The radiographic assessments included deformity correction and progressive changes in the major curve angle, pelvic tilt (PT) and coronal balance (CB). The correction of deformities was observed postoperatively and at the patient's 2-year follow-up to test the efficacy of each type of construct. RESULTS: Thirty-three patients were included in this study. There were 14 and 19 patients in the wiring and hybrid construct groups, respectively. The hybrid construct group demonstrated a higher major curve angle correction (50.5° ± 11.2° vs. 36.4° ± 8.4°, p < 0.001), a higher apical vertebral rotation correction (10.6° ± 3.9° vs. 4.8° ± 2.6°, p < 0.001), and a reduced progression of the major curve angle at the 2-year follow-up (5.1° ± 2.9° vs. 8.7° ± 4.8°, p < 0.001). A moderate correlation was observed between the magnitude of correction of the apical vertebral rotation angle and the major curve (r = 0.528, p = 0.002). CONCLUSION: This study demonstrated that hybrid instrumentation can provide a greater magnitude of correction in major curve and apical rotation as well as less major curve progression than sublaminar wire instrumentation alone in patients with SMA scoliosis. Level of evidence III.

Ultrasound assisted lumbar intrathecal administration of nusinersen in adult patients with spinal muscular atrophy: A case series.

INTRODUCTION/AIMS: Intrathecal nusinersen administration can be challenging in certain adult spinal muscular atrophy (SMA) patients with difficult spinal anatomy who require imaging techniques (fluoroscopy or computed tomography scans) or invasive approaches (catheter placement, laminotomy) to identify the intrathecal space. We used ultrasound (US) assistance to access the lumbar intrathecal space in patients with SMA who experienced previous difficulties or failures with intrathecal dosing. METHODS: Eighteen adult patients with difficult spines were enrolled. We used US assistance, and we recorded the successful administrations, number of attempts, procedure times, and "patient satisfaction." RESULTS: There were 57 consecutive successful nusinersen spinal administrations in all patients enrolled. In 50% of patients, two or fewer attempts were needed to obtain a successful administration, with four or fewer attempts in 83.3%; only three patients reported more than four attempts because of both severe scoliosis and severe spine rotation (two patients) and obesity (one patient). The mean procedure time was 11.8 min (range, 1.7-28.9). Patient satisfaction was 4.97/5 (range, 4-5; median, 5) on Likert scale at 5 min and at 72 h. No major adverse events were reported, and two post dural puncture headaches were managed with medical therapy and with complete resolution within 72 h. DISCUSSION: US assistance seems to be a valid option among treatment choices for intrathecal nusinersen administration in patients with difficult spine. The absence of radiation exposure and the lack of need for intravenous sedation or general anesthesia are additional potential advantages to US assisted administration.

Intrathecal catheter and port placement for nusinersen infusion in children with spinal muscular atrophy and spinal fusion.

BACKGROUND: Spinal administration of medications is challenging in patients with complete posterior spinal fusion. We describe percutaneous image-guided intrathecal port placement for administration of the antisense oligonucleotide nusinersen for children and young adults with spinal muscular atrophy. OBJECTIVE: To describe and present our initial experience with a new technique for administering nusinersen in patients with spinal muscular atrophy and posterior spinal fusion. MATERIALS AND METHODS: We reviewed medical records of 13 patients who received intrathecal ports using DynaCT, biplane fluoroscopy and iGuide from April 2018 through June 2019, and we describe the clinical course over 1 year. RESULTS: Image-guided catheter and port implantation was successful in all cases. Two ports were subsequently removed, one for persistent cerebrospinal fluid leak and one for superficial infection. The other 11 have functioned successfully for a minimum of 23 months. CONCLUSION: We report our experience with image-guided intrathecal port placement in children with complete posterior spine fusion. The implanted port permits dosing in an outpatient setting and avoids the need for multiple future radiologic procedures, and it reduces discomfort, procedural costs and potential risks and sequelae of multiple anesthetics and radiation exposures. Further studies are needed to define the relative risks and benefits of intrathecal ports compared to other approaches such as repeated transforaminal lumbar punctures.

Ultra-low radiation dose protocol for CT-guided intrathecal nusinersen injections for patients with spinal muscular atrophy and severe scoliosis.

PURPOSE: Intrathecal injection of nusinersen is an approved treatment of spinal muscular atrophy (SMA). CT-guided injection is a method of nusinersen administration in patients with severe scoliosis, in whom standard lumbar puncture is not feasible. The injections are repeated every 4 months for life, and accumulated radiation doses absorbed by the patient can increase the risk of cancer. In this study, we present the results of CT-guided intrathecal nusinersen injections with an ultra-low radiation dose protocol. METHODS: Eighteen patients (15 adults and three children) in whom standard lumbar puncture was not feasible due to severe scoliosis or spinal stabilization were included in this retrospective study. The first 23 injections were performed with a standard radiation dose protocol and the next 42 injections with an ultra-low-dose protocol. The radiation doses, measured as total dose length product (DLP), were acquired and compared between the protocols. RESULTS: Injections were successful in 100% of patients with both ultra-low-dose and standard protocols. The radiation dose, measured as DLP, was 111.2-1100.7 (Me = 248.1) mGy*cm for the standard protocol. For the ultra-low-dose protocol, the dose range was 5.0-54.4 (Me = 26.7) mGy*cm, which was significantly lower than with the standard protocol (p < 0.001, η2 = 0.67). CONCLUSION: Radiation doses can be significantly decreased in the CT-guided injection of nusinersen. The proposed protocol allows for effective CT-guided intrathecal nusinersen administration in patients with SMA and severe scoliosis.

Transforaminal intrathecal delivery of nusinersen for older children and adults with spinal muscular atrophy and complex spinal anatomy: an analysis of 200 consecutive injections.

BACKGROUND: Nusinersen is the only approved treatment for all spinal muscular atrophy (SMA) subtypes and is delivered intrathecally. Distorted spinal anatomy and instrumentation preclude standard approaches for intrathecal access, necessitating alternative techniques for delivery. The purpose of this study is to report technical success and adverse events of transforaminal intrathecal delivery of nusinersen. METHODS: 28 patients, mean age 24.1±9.8 years (range 10.0-51.0 years), with intermediate or late onset SMA, underwent a combined 200 transforaminal nusinersen injections. All patients had osseous fusion or spinal instrumentation precluding standard posterior access routes. Patients who underwent nusinersen injections using a technique other than transforaminal lumbar puncture (n=113) were excluded. Technical success, adverse events (AEs) and radiation exposure were recorded. RESULTS: 200 (100%) procedures were technically successful; 6 (3%) required a second level of attempt for access. 187 (93.5%) interventions were completed using cone beam computed tomography (CBCT) with two-axis fluoroscopic navigational overlay. 13 (6.5%) procedures were performed with fluoroscopic-guidance only at subsequent sessions. There were 8 (4.0%) mild AEs and 2 (0.5%) severe AEs; one patient received antibiotics for possible traversal of the large bowel but did not develop meningitis, and one patient developed aseptic meningitis. Mean air kerma was 74.5±161.3 mGy (range 5.2-1693.0 mGy). CONCLUSION: Transforaminal intrathecal delivery of nusinersen is feasible and safe for gaining access in patients with distorted spinal anatomy. The use of CBCT delineates anatomy and optimizes needle trajectory during the initial encounter, and may be used selectively for subsequent procedures.

Correlation of Pulmonary Function to Novel Radiographic Parameters of Collapsing Parasol Deformity in Spinal Muscular Atrophy.

Spinal muscular atrophy (SMA) is a neuromuscular disease with manifestations of scoliosis, pulmonary function decline, and, uniquely, collapse of the ribs. Methods to quantify rib deformity and its impact on pulmonary function are sparse. The authors propose new radiographic measurements to quantify the aspect of SMA known as collapsing parasol deformity and correlate these measurements with pulmonary function. Twenty-eight full-spine radiographs of pediatric SMA patients were measured twice by 3 independent investigators, with 2 weeks separating each measurement. Radiographic measurements, demographics, spirometry results, and assisted ventilation rating were obtained. Twenty-one patients with spirometry metrics were assessed to correlate pulmonary function and spinal measurements. The intrarater intraclass correlation coefficient (ICC) for the measurements ranged from 0.706 to 0.99, and the interrater ICC ranged from 0.64 to 0.97. Eighteen of 19 variables had ICC values greater than 0.75 for inter- and intrarater reliability. Twenty-one patients with forced expiratory volume in 1 second and forced vital capacity were assessed in terms of these measurements. Ratio of the concave hemithoracic width at T6/convex hemithoracic width at T6 (P=.004) and ratio of convex vertical rib displacement at the apical rib/concave vertical rib displacement (P=.021) were both significantly correlated with decreased pulmonary function. No significant correlation was found examining the average vertical rib displacement at the apical rib. High inter-and intrarater reliability can be obtained in a variety of spinal measurements of SMA patients. Various measurements are correlated to diminished pulmonary function, specifically variables showing asymmetric changes in the chest cavity. [Orthopedics. 2021;44(2):e287-e293.].

Scoliosis in spinal muscular atrophy: is the preoperative magnetic resonance imaging necessary?

PURPOSE: To determine the prevalence of intraspinal alterations in scoliosis due to Spinal Muscular Atrophy (SMA). METHODS: Cross-sectional, observational, descriptive study. Fifty-six patients with SMA diagnosis required surgical treatment due to scoliosis. INCLUSION CRITERIA: scoliosis/kyphoscoliosis > 50 degrees in the coronal plane, clinical characteristics of Spinal Muscular Atrophy, accurate diagnosis by means of molecular or genetic study. Prior to the spinal surgery, and to find related intraspinal alterations, MRI of the spine and posterior cranial fossa was performed. RESULTS: Forty females, 16 males, mean age 11 years (range 6-14 years). 94% of the patients had Spinal Muscular Atrophy type 2. The mean angle value was 81 degrees (range 53-122 degrees) in the coronal plane and 62 degrees (range 35-80 degrees) in the sagittal plane. The prevalence of intraspinal alterations was 1.78%. One patient with cervical hydromyelia and no neurological surgical procedure prior to the spinal deformity surgery was reported. CONCLUSIONS: In the context of preoperative planning and strategy of patients with scoliosis due to Spinal Muscular Atrophy, MRI may have not to be requested.

Radiation dose reduction for CT-guided intrathecal nusinersen administration in adult patients with spinal muscular atrophy.

Intrathecal administration of nusinersen in adult spinal muscular atrophy (SMA) patients with scoliosis and spondylodesis requires image guidance, which is preferably achieved with multi-detector computed tomography (MDCT). As long-term treatment is necessary and patients are young, radiation doses should be reduced to a minimum whilst a sufficient image quality for precise interventional performance should be kept. We compared 44 MDCT standard-dose scans (133.0-200.0 mA) with a hybrid iterative reconstruction (iDose4) to 20 low-dose scans (20.0-67.0 mA) with iterative model reconstruction (IMR), which were performed for procedure planning of intrathecal nusinersen administration in 13 adult patients with SMA and complex spinal conditions. Qualitative image evaluation, including confidence for intervention planning, was performed by two neuroradiologists for standard- and low-dose scans. All 64 MDCT-guided intrathecal administrations of nusinersen were successful. The dose length product (DLP) was significantly lower when using low-dose scanning with IMR (median DLP of standard-dose scans: 92.0 mGy•cm vs. low-dose scans: 34.5 mGy•cm; p < 0.0001). Image quality was significantly reduced for low-dose compared to standard-dose scanning. However, bone/soft tissue contrast and confidence for intervention planning were not significantly impaired in low-dose MDCT according to both readers, showing good inter-reader agreement. Thus, we hereby demonstrate a low-dose MDCT protocol combined with advanced image reconstruction for scanning during procedure planning as a viable option for image guidance in intrathecal nusinersen treatment of adult SMA patients with complex spinal conditions.

Collapse of VBX Balloon-Expandable Endoprosthesis in Bilateral Common Iliac Arteries in a Lean, Elderly Patient with Bent Back.

An 87-year-old woman who had previously received bare nitinol self-expandable stent implantation twice into the bilateral common iliac artery (CIA) due to repeated in-stent restenosis presented with acute onset of intermittent claudication. Computed tomography (CT) showed bilateral CIA obstruction with thrombus. Because thrombectomy and ballooning did not achieve recanalization, kissing VBX balloon-expandable endoprostheses were deployed in both CIAs, which resolved the patient's symptoms. However, the symptoms recurred 9 days later, and CT revealed collapsed VBX stent grafts surrounded by blood thrombus. X-rays showed spinal compression of the VBX stent while standing, which might have caused the collapse. We report a case of the collapse of a VBX balloon-expandable endoprosthesis in the bilateral CIAs of an elderly patient with a bent back. Physicians should consider that a bent back could be the cause of VBX collapse even in the CIA when elderly persons present with this deformity.

Camptocormia as the presenting symptom in sporadic late onset nemaline myopathy: a case report.

BACKGROUND: Camptocormia has been reported in a plethora of diseases comprising disorders of the central nervous system, the peripheral nervous system, and the neuromuscular junction as well as hereditary and acquired myopathies. In sporadic late onset nemaline myopathy concomitant axial myopathy is common, but reports about camptocormia as the only presenting symptom in this condition are very rare. Notably, sporadic late onset nemaline myopathy is a potentially treatable condition in particular when associated with monoclonal gammopathy of unknown significance, HIV or rheumatological disorders. CASE PRESENTATION: We report the case of a 62-year-old female patient, who presented with slowly progressive camptocormia. Comprehensive work-up including neurological work-up, laboratory tests, MR-imaging, muscle biopsy and genetic testing led to the diagnosis of sporadic late onset nemaline myopathy. CONCLUSIONS: Our case report highlights that sporadic late onset nemaline myopathy has to be considered in patients presenting with isolated camptocormia and comprehensive work-up of camptocormia is mandatory to ascertain the individual diagnosis, especially in consideration of treatable conditions.

Surgical management of camptocormia in Parkinson's disease: systematic review and meta-analysis.

OBJECTIVE: Camptocormia is a potentially debilitating condition in the progression of Parkinson's disease (PD). It is described as an abnormal forward flexion while standing that resolves when lying supine. Although the condition is relatively common, the underlying pathophysiology and optimal treatment strategy are unclear. In this study, the authors systematically reviewed the current surgical management strategies for camptocormia. METHODS: PubMed was queried for primary studies involving surgical intervention for camptocormia in PD patients. Studies were excluded if they described nonsurgical interventions, provided only descriptive data, or were case reports. Secondarily, data from studies describing deep brain stimulation (DBS) to the subthalamic nuclei were extracted for potential meta-analysis. Variables showing correlation to improvement in sagittal plane bending angle (i.e., the vertical angle caused by excessive kyphosis) were subjected to formal meta-analysis. RESULTS: The query resulted in 9 studies detailing treatment of camptocormia: 1 study described repetitive trans-spinal magnetic stimulation (rTSMS), 7 studies described DBS, and 1 study described deformity surgery. Five studies were included for meta-analysis. The total number of patients was 66. The percentage of patients with over 50% decrease in sagittal plane imbalance with DBS was 36.4%. A duration of camptocormia of 2 years or less was predictive of better outcomes (OR 4.15). CONCLUSIONS: Surgical options include transient, external spinal stimulation; DBS targeting the subthalamic nuclei; and spinal deformity surgery. Benefit from DBS stimulation was inconsistent. Spine surgery corrected spinal imbalance but was associated with a high complication rate.

A recurrent de novo DYNC1H1 tail domain mutation causes spinal muscular atrophy with lower extremity predominance, learning difficulties and mild brain abnormality.

We describe four unrelated patients with the same de novo heterozygous missense mutation c.751C>T in the DYNC1H1 gene. We found a high phenotype-genotype correlation with all four patients having early childhood-onset predominant lower limb muscle weakness and wasting which was slowly progressing and later-onset mild upper extremities proximal weakness. All four patients presented minor cognitive dysfunction with learning difficulty and developmental behavioural comorbidities with mild abnormalities in the brain MRI. The leg muscle MRI findings are highly consistent in DYN1CH1-related spinal muscular atrophy with lower limb predominance (SMALED) with relative sparing of biceps femoris and semitendinosus, and hypertrophy of adductor longus in the thighs; and sparing the anterior and medial muscles in the calves. This report provides important clinical evidence indicating the de novo heterozygous missense mutation c.751C>T in the DYNC1H1 gene is pathogenic causing SMALED. Muscle MRI is more specific than muscle biopsy in the diagnosis of SMALED.

Cervical puncture to deliver nusinersen in patients with spinal muscular atrophy.

OBJECTIVE: To report our experience delivering intrathecal nusinersen through cervical puncture in patients with spinal muscular atrophy (SMA) with no lumbar access. BACKGROUND: SMA is a neuromuscular disorder characterized by profound muscle weakness, atrophy, and paralysis due to degeneration of the anterior horn cells. Nusinersen, the first Food and Drug Administration-approved treatment for SMA, is administered intrathecally via lumbar puncture; however, many patients with SMA have scoliosis or solid spinal fusion with hardware that makes lumbar access impossible. Studies in primates have demonstrated better spinal cord tissue concentration with intrathecal injections than with intracerebral ventricular injections. Therefore we have used C1/C2 puncture as an alternative to administer nusinersen. METHOD: Retrospective chart review. RESULTS: Intrathecal nusinersen via cervical puncture was given to 3 patients who had thoracic and lumbosacral spinal fusion: a 12-year-old girl with type 1 SMA and 2 17-year-old girls with type 2 SMA. Cervical puncture was performed without deep sedation under fluoroscopic guidance using a 25-G or a 24-G Whitacre needle in the posterior aspect of C1-C2 interspace and full dose of nusinersen (12 mg/5 mL) was injected after visualizing free CSF flow. Patients completed their 4 loading doses and first maintenance dose of nusinersen, and 15 procedures were successful and well-tolerated. CONCLUSION: Cervical puncture is a feasible alternative delivery route to administer intrathecal nusinersen in patients with longstanding SMA and spine anatomy precluding lumbar access when done by providers with expertise in this procedure.

[A survivor of Hodgkin lymphoma manifesting dropped head syndrome as a late-onset complication of radiotherapy: a case report].

We report the case of a 50-year-old female survivor of Hodgkin lymphoma (HL), who developed dropped head syndrome (DHS). The patient was diagnosed with HL at 20 years of age, and underwent chemo-radiotherapy, which led to complete remission. Undergoing supplemental therapy for post-radiation hypothyroidism, she had twin babies. She noticed white stains on her neck at the age of 30, and the decolored area gradually expanded. Sixteen years after the radiotherapy (RT), her posterior neck muscle strength began to decline. She had to make considerable efforts to keep her neck straight, and came to experience a severe pain in the neck and shoulders. The patient visited our department due to DHS at the age of 50. She had leukoderma, muscle weakness, and muscle atrophy in the neck and para-spinal region, which were consistent with the area of RT. The strength was preserved in the other parts of the muscle, including the proximal upper limbs. Sensory nerve disorder was not detected. The serum creatine kinase level was slightly elevated. Cervical spine or cervical cord disease that can cause DHS was not detected by MRI examination. The MRI and CT images revealed marked atrophy in the posterior neck and para-spinal muscles. The electromyogram revealed myopathic changes, and the cause of her DHS was diagnosed as radiation-induced myopathy. DHS is a well-known late-onset radiation injury, and Japanese cases have been reported in elderly persons with laryngeal or lung cancer. However, there have been no Japanese case reports of radiation-induced DHS due to RT against HL in younger persons. The patient had visited several clinics and hospitals before she came to our hospital, but RT-induced DHS had been overlooked. Greater recognition and consideration is required for DHS as one of the various issues arising after long passage of HL survivors.

The metabolic and endocrine characteristics in spinal and bulbar muscular atrophy.

OBJECTIVE: Spinal and bulbar muscular atrophy (SBMA) is caused by an abnormal expansion of the CAG repeat in the androgen receptor gene. This study aimed to systematically phenotype a German SBMA cohort (n = 80) based on laboratory markers for neuromuscular, metabolic, and endocrine status, and thus provide a basis for the selection of biomarkers for future therapeutic trials. METHODS: We assessed a panel of 28 laboratory parameters. The clinical course and blood biomarkers were correlated with disease duration and CAG repeat length. A subset of 11 patients was evaluated with body fat MRI. RESULTS: Almost all patients reported muscle weakness (99%), followed by dysphagia (77%), tremor (76%), and gynecomastia (75%) as major complaints. Creatine kinase was the most consistently elevated (94%) serum marker, which, however, did not relate with either the disease duration or the CAG repeat length. Paresis duration and CAG repeat length correlated with dehydroepiandrosterone sulfate after correction for body mass index and age. The androgen insensitivity index was elevated in nearly half of the participants (48%). CONCLUSIONS: Metabolic alterations in glucose homeostasis (diabetes) and fat metabolism (combined hyperlipidemia), and sex hormone abnormalities (androgen insensitivity) could be observed among SBMA patients without association with the neuromuscular phenotype. Dehydroepiandrosterone sulfate was the only biomarker that correlated strongly with both weakness duration and the CAG repeat length after adjusting for age and BMI, indicating its potential as a biomarker for both disease severity and duration and, therefore, its possible use as a reliable outcome measure in future therapeutic studies.