Saccadic delay in multiple sclerosis: A quantitative description.

In multiple sclerosis (MS), eye movement disorders are common and can be quantified with infrared video-oculography. A well-known abnormality is internuclear ophthalmoplegia (INO). This study aims to describe saccadic abnormalities beyond INO and investigate their clinical relevance. A validated standardized infrared oculography protocol, DEMoNS, was used for quantifying saccadic eye movements in three different tasks in MS patients and healthy controls. The relationship between the saccadic parameters and disease characteristics was investigated. Furthermore, the association between saccadic parameters and visual functioning was analysed using logistic regression models, adjusted for possible confounders. This cross-sectional study included 218 subjects with MS and 58 healthy controls. The latency of all saccades was longer in MS patients than in healthy controls. This saccadic delay was larger in subjects with a longer disease duration and more disabled subjects. Furthermore, it was significantly related to presence of a lower vision-related quality of life. This study provided a comprehensive overview of performance of MS patients in different saccadic tasks, compared to healthy controls. Saccadic delay in MS patients was present in all saccadic tasks and was related to advancing disease and visual functioning in daily life.

Objective quantification of vitreous haze on optical coherence tomography scans: no evidence for relationship between uveitis and inflammation in multiple sclerosis.

BACKGROUND AND PURPOSE: The occurrence of intermediate uveitis, which is characterized by the presence of vitreous haze (VH), in patients with multiple sclerosis (MS) may be a sign of coexistent inflammatory central nervous system (CNS) disease activity. Using an automated algorithm to quantify VH on optical coherence tomography (OCT) scans, the aim was to investigate whether VH in MS patients is associated with signs of inflammatory CNS disease activity. METHODS: Vitreous haze was quantified on OCT macular volume scans of 290 MS patients and 85 healthy controls (HCs). The relationship between VH and clinical, retinal OCT and magnetic resonance imaging parameters of inflammatory disease activity was investigated using generalized estimating equations. RESULTS: Mean VH scores did not differ between patients and HCs (P = 0.629). Six patients (2.1%) showed values higher than the highest of the controls by HCs. VH scores did not differ between the different disease types or between eyes with and without a history of optic neuritis (P = 0.132). VH was not associated with inner nuclear layer volume on OCT (P = 0.233), cerebral T2 lesion load on magnetic resonance imaging (P = 0.416) or the development of new relapses (P = 0.205). CONCLUSION: In this study, OCT-based automated VH estimation did not detect increased vitreous inflammation in MS patients compared to HCs and did not find an association with CNS inflammatory burden.

Progression of Anterograde Trans-Synaptic Degeneration in the Human Retina Is Modulated by Axonal Convergence and Divergence.

In the visual pathway of patients with multiple sclerosis (MS), the inner nuclear layer (INL) of the retina is a tight barrier for retrograde trans-synaptic degeneration. In this observational, retrospective cross-sectional study, segmented macular spectral domain optical coherence tomography (OCT) volume scans were reviewed to investigate if this observation also holds true for anterograde trans-synaptic degeneration. Significant thinning was found in all retinal layers in patients with outer retinal diseases compared with the healthy controls, while there was no significant attenuation of the outer retina in patients with MS. In contrast to the tight barrier function observed with retrograde trans-synaptic degeneration, the INL appears to be more permissive for the propagation of anterograde trans-synaptic degeneration. We speculate that this may be due to the size of the area affected and be explained by convergence and divergence of axons within the retinal layers. These findings are likely relevant to future restorative stem cell treatment of the outer retinal layers, as time may matter.

Pulsed electromagnetic field stimulation may improve fusion rates in cervical arthrodesis in high-risk populations.

OBJECTIVES: Pulsed electromagnetic field (PEMF) stimulation was evaluated after anterior cervical discectomy and fusion (ACDF) procedures in a randomized, controlled clinical study performed for United States Food and Drug Administration (FDA) approval. PEMF significantly increased fusion rates at six months, but 12-month fusion outcomes for subjects at elevated risk for pseudoarthrosis were not thoroughly reported. The objective of the current study was to evaluate the effect of PEMF treatment on subjects at increased risk for pseudoarthrosis after ACDF procedures. METHODS: Two evaluations were performed that compared fusion rates between PEMF stimulation and a historical control (160 subjects) from the FDA investigational device exemption (IDE) study: a post hoc (PH) analysis of high-risk subjects from the FDA study (PH PEMF); and a multicentre, open-label (OL) study consisting of 274 subjects treated with PEMF (OL PEMF). Fisher's exact test and multivariate logistic regression was used to compare fusion rates between PEMF-treated subjects and historical controls. RESULTS: In separate comparisons of PH PEMF and OL PEMF groups to the historical control group, PEMF treatment significantly (p < 0.05, Fisher's exact test) increased the fusion rate at six and 12 months for certain high-risk subjects who had at least one clinical risk factor of being elderly, a nicotine user, osteoporotic, or diabetic; and for those with at least one clinical risk factor and who received at least a two- or three-level arthrodesis. CONCLUSION: Adjunctive PEMF treatment can be recommended for patients who are at high risk for pseudoarthrosis.Cite this article: D. Coric, D. E. Bullard, V. V. Patel, J. T. Ryaby, B. L. Atkinson, D. He, R. D. Guyer. Pulsed electromagnetic field stimulation may improve fusion rates in cervical arthrodesis in high-risk populations. Bone Joint Res 2018;7:124-130. DOI: 10.1302/2046-3758.72.BJR-2017-0221.R1.

Postoperative troponin measurement as a screening tool for adverse cardiac events in adult patients undergoing moderate or major non-cardiac surgery.

Elevated troponin levels within three days of surgery are strongly linked to major adverse cardiac events (MACE). However, the value of screening with troponin measurements is controversial. The extent to which this is done in routine practice is uncertain. We examined the medical records of all patients ≥45 years of age undergoing moderate or major non-cardiac surgery in our tertiary referral hospital over a six-month period. We determined how many patients had a troponin (TnT) measurement recorded in the first three days postoperatively, how many of these were abnormal, and the occurrence of MACE within 30 days. Two thousand and two hundred patients underwent 2,577 operations that met the study criteria. A postoperative TnT was measured after 4.5% of operations. Thirty-eight percent of patients with a recorded TnT measurement, and 44% of those with an abnormal measurement, experienced a MACE within 30 days. The sensitivity of an abnormal TnT to detect MACE was 86%. The specificity was low at 32% with a false positive rate of 56%. Patients with an abnormal TnT result had an increased risk of MACE (23%). The 'number needed to measure' to detect one patient with MACE was 4.4. In our institution, postoperative TnT levels were rarely measured and were used as a diagnostic rather than as a screening tool. The high false positive rate for MACE prediction limits its potential value as a screening tool. The test could be considered useful if it leads to further investigation, and may be best considered as one component of a multivariate approach to cardiac risk evaluation and diagnosis.

Diagnostic accuracy of optical coherence tomography inter-eye percentage difference for optic neuritis in multiple sclerosis.

BACKGROUND AND PURPOSE: Multiple sclerosis-associated optic neuritis (MSON) causes atrophy of the inner retinal layers, which can be quantified by optical coherence tomography. It has been suggested that the inter-eye percentage difference (IEPD) of atrophy may be of diagnostic value in MSON. METHODS: This was a prospective, cross-sectional study in patients with multiple sclerosis and healthy controls (HCs). Spectral-domain optical coherence tomography of both eyes was performed, followed by automated retinal layer segmentation of the peri-papillary retinal nerve fibre layer (pRNFL) and macular ganglion cell and inner plexiform layer (mGCIPL). Receiver operator characteristics curves were plotted and the area under the curve was calculated for group comparisons of the IEPD of the pRNFL and mGCIPL. RESULTS: There were 39 patients with bilateral MSON, 62 patients with unilateral MSON, 106 patients without MSON and 63 HCs. Diagnostic accuracy (area under the curve) of the IEPD was 0.73-0.86 for the pRNFL and 0.75-0.94 for the mGCIPL. The diagnostic sensitivity of the mGCIPL IEPD was 70% with a specificity of 97% for distinguishing unilateral MSON from HCs. For the comparison of bilateral MSON with HCs, sensitivity was 86% with a specificity of 97%. CONCLUSIONS: The IEPD of the pRNFL, and more particularly the IEPD of the mGCIPL, is a useful diagnostic measure for MSON. The IEPD is a dimensionless unit and may therefore contribute to overcome device and proprietary segmentation algorithm limitations.

[The type of agent auto-intoxication and the degree of suicidal intent]. / Type geneesmiddel en suïcidale intentie na auto-intoxicatie.

BACKGROUND: The type of the agent used for auto-intoxication may increase or decrease the degree of suicidal intent. AIM: To find out whether the type of agent used for auto-intoxication is linked to the degree of suicidal intent at the moment when a patient is given a psychiatric assessment in a general hospital. METHOD: We studied the files of 211 patients who had been assessed following auto-intoxication. The files provided us with information about the type of agent used, the suicidal intent of the patient at the time and about other recent, relevant risk factors. RESULTS: At the time of the assessment, benzodiazepines were the only auto-intoxication agents used which seemed to predict suicidal intent. CONCLUSION: Although the results need to be verified in further studies, it can be concluded that auto-intoxication induced only by benzodiazepines can be seen as a serious expression of an individual's wish to die.

Primary stenting of the extracranial internal carotid artery in a patient with multiple cervical dissections: technical case report.

OBJECTIVE AND IMPORTANCE: Spontaneous dissection of the extracranial internal carotid artery (ICA) and vertebral artery (VA) is a well-documented cause of stroke in young, previously healthy patients. The majority of patients with spontaneous dissection are successfully treated with antiplatelet or anticoagulation therapy, but a significant proportion of patients progress to suffer devastating morbidity and mortality. Surgical intervention has primarily consisted of proximal ligation, extracranial-intracranial bypass, or endarterectomy. Generally, these procedures are technically demanding and yield disappointing clinical results. CLINICAL PRESENTATION/INTERVENTION: A 36-year-old man without a significant medical history initially presented with a several-day history of episodic right upper extremity weakness and numbness and visual obscurations. Cerebral angiography revealed bilateral ICA long segment narrowing (95%), distal left VA high-grade (95%) stenosis compatible with dissections, and right VA proximal occlusion. While therapeutically anticoagulated on heparin, the patient continued to experience crescendo episodes of right upper extremity paresis and paresthesias as well as aphasia. The patient underwent primary stenting of the left ICA, using a series of six overlapping stents (three Gianturco-Roubin coronary stents and three Palmaz-Schatz coronary stents). The patient remained symptom-free without neurological complications, and subsequent angiography performed at the 9-month follow-up examination confirmed continued patency of the stented left ICA as well as recanalization of the right ICA and VA. CONCLUSION: Neurovascular stents offer a minimally invasive and potentially efficacious treatment for the prevention of cerebral ischemia in patients with spontaneous extracranial dissection who remain symptomatic despite therapeutic anticoagulation.

A clinical comparison of one- and two-screw odontoid fixation.

OBJECT: The optimal treatment of Type II odontoid fractures is controversial. Various therapies have been used, including nonrigid immobilization, halo orthosis, posterior atlantoaxial arthrodesis, and odontoid screw fixation. Of these, odontoid screw fixation is the only treatment modality that provides immediate stabilization and preserves normal motion at C1-2. It has been suggested in cadaveric biomechanical studies that there is no advantage to using more than one screw for anterior odontoid fixation. The authors compared the clinical safety and efficacy of one- and two-screw anterior odontoid fixation. METHODS: The authors retrospectively reviewed the medical records and radiographs of 42 consecutive patients who had undergone fixation for treatment of odontoid fractures at a single institution between 1989 and 1995. The group treated with a single screw consisted of 20 patients (11 males and nine females) with an average age of 54 years. The union rate in this group, as determined by postoperative dynamic radiographs, was 81%. The group treated with two screws consisted of 22 patients (13 men and nine women) with an average age of 64 years, whose union rate was 85%. CONCLUSIONS: Anterior odontoid screw fixation is a safe and efficacious treatment for odontoid fractures. In the authors' experience there was no significant difference in the successful union rates achieved with either the one- or two-screw fixation techniques (81% and 85%, respectively; chi(2) = 0.09, p = 0.76).

Posterior lumbar interbody fusion in the treatment of symptomatic spinal stenosis.

Lumbar spinal stenosis is often the result of advanced degeneration of motion segments of the lumbar spine. Loss of disc height, facet displacement and hypertrophy, spondylosis, and spondylolisthesis, as well as buckling of the ligamentum flavum and annulus fibrosus, all contribute to impingement on the spinal canal and intervertebral foramen in lumbar stenosis. There is a subgroup of patients with spinal stenosis in whom the spine is unstable preoperatively or becomes destabilized following decompression who would benefit from an initial fusion procedure. Posterior lumbar interbody fusion (PLIF) addresses several aspects of the multifactorial pathophysiology responsible for spinal stenosis and may arrest the degenerative changes at the fused level. Fusion, in particular PLIF, should be considered in complex cases of lumbar spinal stenosis, most notably in patients with postlaminectomy stenosis or stenosis associated with spondylolisthesis.

Revision of anterior cervical pseudoarthrosis with anterior allograft fusion and plating.

Anterior cervical discectomy and fusion is an efficacious procedure used to treat a variety of cervical spinal disorders, including spondylosis, myelopathy, herniated discs, trauma, and degenerative disc disease. Pseudarthrosis, or failure of fusion, may be the most common complication of spinal fusion procedures. Nineteen consecutive patients with symptomatic pseudarthrosis following failed anterior cervical fusions were treated with anterior cervical revision using iliac crest allografts and either the Cervical Spine Locking Plate system (10 patients) or the Trapezial Osteosynthetic Plate system (nine patients). The mean age of the nine men and 10 women undergoing treatment was 49.1 years (range 25-72 years). Eleven patients (57.9%) exhibited pseudarthrosis at one level, six (31.5%) at two levels, and two (10.5%) at three levels. The indications for revision were intractable neck pain with radiculopathy (17 patients) or myelopathy (two patients), with evidence of pseudarthrosis on plain cervical radiography as well as computerized tomography (CT) or single-photon emission computerized tomography (SPECT) scanning, or both. All eight patients evaluated with SPECT showed increased focal uptake consistent with pseudarthrosis, which was subsequently confirmed intraoperatively in all eight. The average follow-up period was 22.4 months (range 12-42 months). Solid osseous fusion was achieved over all 28 levels in all 18 patients available for follow-up review (100%). One patient died 4 months postoperatively from myocardial infarction related to preexisting coronary artery disease. There were no intraoperative complications; postoperatively, two patients (10.5%) experienced transient hoarseness. Anterior revision of failed cervical fusions using allograft interbody fusion material and anterior plating is a safe and efficacious procedure. In this series, the use of allografts avoided donor site morbidity without adversely affecting fusion rates. Rigid internal fixation was achieved by means of anterior plating without increasing surgical morbidity rates. The SPECT imaging technique has the potential to reliably confirm the diagnosis of pseudarthrosis.

Treatment of traumatic spondylolisthesis of the axis with nonrigid immobilization: a review of 64 cases.

Current treatment regimens for hangman's fracture, or traumatic spondylolisthesis of the axis, emphasize rigid immobilization using a halo orthosis. A retrospective study was undertaken to assess the safety and efficacy of nonrigid immobilization in the treatment of these fractures. Records of 64 patients with hangman's fracture treated over a 19-year period (1975-1994) at one institution were reviewed. Thirty-nine of these patients presented with a displacement of C-2 onto C-3 measuring less than 6 mm and no contiguous cervical fractures. All these patients were treated with nonrigid immobilization, consisting primarily of a Philadelphia hard collar worn for 10 to 14 weeks; all showed stable fracture healing on follow-up flexion-extension radiographs. None of the patients experienced neurological sequelae or significant disability at follow-up review. The results of this series indicate that the majority of patients with hangman's fractures, including all patients with displacement measuring less than 6 mm and no contiguous fractures, may be treated successfully with nonrigid immobilization. This management regimen avoids the increased morbidity and cost associated with rigid immobilization using a halo orthosis.

Arteriovenous fistula as a complication of C1-2 transarticular screw fixation. Case report and review of the literature.

A case is reported of a vertebral artery-to-epidural venous plexus fistula as a complication of posterior atlantoaxial facet screw fixation. The use of transarticular screws to stabilize the C1-2 joint has become an increasingly popular fixation technique, most notably for atlantoaxial instability due to trauma or rheumatoid disease. Despite the fact that this approach is technically challenging, there have been few reports of complications associated with C1-2 transarticular fixation. Although damage to the vertebral artery is a documented hazard of transarticular fixation at this level, a symptomatic arteriovenous fistula resulting from the procedure has not been described previously. The etiology, presentation, and treatment of this unusual complication are discussed.