Olivary body exposure through far lateral and lower retrosigmoid approaches. Comparative analysis of the exposed surface and angle of attack

OBJECTIVES

Throughout neurosurgical history, the treatment of intrinsic lesions located in the brainstem has been subject of much controversy. The brainstem is the anatomical structure of the central nervous system (CNS) that presents the highest concentration of nuclei and fibers, and its simple manipulation can lead to significant morbidity and mortality. Once one of the safe entry points at the medulla oblongata has been established, we wanted to evaluate the safest approach to the olivary body (the most used safe entry zone on the anterolateral surface of the medulla oblongata). The proposed objective was to evaluate the working channel from the surface of each of the far lateral and retrosigmoid approaches to the olivary body: distances, angles of attack and channel content.

MATERIAL AND METHODS

To complete this work, a total of 10 heads injected with red/blue silicone were used. A total of 40 approaches were made in the 10 heads used (20 retrosigmoid and 20 far lateral). After completing the anatomical study and obtaining the data referring to all the approaches performed, it was decided to expand the sample of this research study by using 30 high-definition magnetic resonance imaging of anonymous patients without cranial or cerebral pathology. The reference points used were the same ones defined in the anatomical study. After defining the working channels in each of the approaches, the working distances, angle of attack, exposed surface, and the number of neurovascular structures present in the central trajectory were analyzed.

RESULTS

The distances to the cranial and medial region of the olivary body were 52.71 mm (SD 3.59) from the retrosigmoid approach and 27.94 mm (SD 3.99) from the far lateral; to the most basal region of the olivary body, the distances were 49.93 (SD 3.72) from the retrosigmoid approach and 18.1 mm (SD 2.5) from the far lateral. The angle of attack to the caudal region was 19.44° (SD 1.3) for the retrosigmoid approach and 50.97° (SD 8.01) for the far lateral approach; the angle of attack to the cranial region was 20.3° (SD 1.22) for the retrosigmoid and 39.9° (SD 5.12) for the far lateral. Regarding neurovascular structures, the probability of finding an arterial structure is higher for the lateral far, whereas a neural structure will be more likely from a retrosigmoid approach.

CONCLUSIONS

As conclusions of this work, we can say that far lateral approach presents more favorable conditions for the microsurgical treatment of intrinsic bulbar and bulbomedullary lesions approached through the caudal half of the olivary body. In those cases of bulbar and pontine-bulbar lesions approached through the cranial half of the olivary body, the retrosigmoid approach can be considered for selected cases.

Lateral medullary vascular compression manifesting as paroxysmal hypertension

Neurovascular compression of the rostral ventrolateral medulla (RVLM) has been described as a possible cause of refractory essential hypertension. We present the case of a patient affected by episodes of severe paroxysmal hypertension, some episodes associated with vago-glossopharyngeal neuralgia. Classical secondary forms of hypertension were excluded. Imaging revealed a neurovascular conflict between the posterior inferior cerebellar artery (PICA) and the ventrolateral medulla at the level of the root entry zone of the ninth and tenth cranial nerves (CN IX-X REZ). A MVD of a conflict between the PICA and the RVLM and adjacent CN IX-X REZ was performed, resulting in reduction of the frequency and severity of the episodes. Brain MRI should be performed in cases of paroxysmal hypertension. MVD can be considered in selected patients.

Formation of a Large Fusiform Aneurysm near a Medullary Infarction Caused by Dissection of the Posterior Inferior Cerebellar Artery

Infarction of the posterior inferior cerebellar artery (PICA) can lead to ischemic stroke in the lateral medullary oblongata. PICA dissection can also elicit an ischemic event in this region, but its detection on radiological images is difficult because of the small diameter of the vessel. We report a case of Wallenberg syndrome due to PICA dissection in a 48-year-old man, which was difficult to diagnose on first admission. He reported sudden onset of sensory disturbance on the right side of his face, ataxic gait, and headache. Brain magnetic resonance imaging (MRI) revealed a fresh cerebral infarct in the right lateral medulla oblongata. Magnetic resonance angiography (MRA) performed at the time of his admission showed no cerebral vessel abnormalities. An MRI study 18 months after the event revealed a fusiform aneurysm on the lateral medullary segment of the PICA, which was extremely close to the cerebral infarct. We concluded that the infarct was due to PICA dissection because of the sudden onset of symptoms and because the infarcted territory of the occluded penetrating branch of the dissecting aneurysm was consistent with Wallenberg syndrome. The aneurysm was trapped and an occipital artery-PICA bypass was placed. At the latest follow-up, 1 year after the procedure, he had no neurological symptoms. Imaging findings at the time of his first admission indicated that the PICA was intact. However, 18 months later, MRI revealed enlargement of an aneurysm at the site of the dissection. A cerebral infarct with headache may indicate PICA dissection.

Attempted Suicide with a Self-Inflicted Penetrating Stab Wound to the Medulla Oblongata Caused by a Pair of Scissors: Case Illustration

A 78-year-old male patient with a history of psychotic depression was found in the bathroom of his apartment with a pair of scissors driven deeply into the back of his neck. He presented with tetraparesis with residual control over the left lower limb movement. Immediate skull radiograph and brain computed tomography scans revealed the tip of the scissors passing into the foramen magnum. Emergent surgery with midline suboccipital craniectomy and resection of the posterior arch of C1 was performed. The scissors were spontaneously dislocated in the course of surgery. Thereafter, debridement, placement of external ventricular drain and primary closure of the dura and skin were achieved. Post-operatively, the patient was not able to follow any instructions. On the 22nd post-operative day, the patient passed away in palliation. To our knowledge, this is the first reported case of a suicide attempt involving the use of scissors reaching the medulla oblongata.

Substitution of Glu to Lys at Codon 332 on the GFAP Gene Alone Is Causative for Adult-onset Alexander Disease

A 57-year-old man whose mother had been pathologically diagnosed with Alexander disease (ALXDRD), presented with cerebellar ataxia, pyramidal signs, and mild dysarthria. Brain magnetic resonance imaging revealed typical ALXDRD alterations, such as atrophy of the medulla oblongata (MO) and cervical spinal cord, a reduced sagittal diameter of the MO, and garland-like hyperintensity signals along the lateral ventricular walls. A genetic analysis of GFAP by Sanger sequencing revealed a single heterozygous mutation of Glu to Lys at codon 332 (c.994G>A) in the GFAP gene. Our results newly confirmed that p.E332K alone is the pathogenic causative mutation for adult-onset ALXDRD.

Radiological correlates of pseudobulbar affect: Corticobulbar and cerebellar components in primary lateral sclerosis

INTRODUCTION

Pseudobulbar affect (PBA) is a distressing symptom of a multitude of neurological conditions affecting patients with a rage of neuroinflammatory, neurovascular and neurodegenerative conditions. It manifests in disproportionate emotional responses to minimal or no contextual stimulus. It has considerable quality of life implications and treatment can be challenging.

METHODS

A prospective multimodal neuroimaging study was conducted to explore the neuroanatomical underpinnings of PBA in patients with primary lateral sclerosis (PLS). All participants underwent whole genome sequencing and screening for C9orf72 hexanucleotide repeat expansions, a comprehensive neurological assessment, neuropsychological screening (ECAS, HADS, FrSBe) and PBA was evaluated by the emotional lability questionnaire. Structural, diffusivity and functional MRI data were systematically evaluated in whole-brain (WB) data-driven and region of interest (ROI) hypothesis-driven analyses. In ROI analyses, functional and structural corticobulbar connectivity and cerebello-medullary connectivity alterations were evaluated separately.

RESULTS

Our data-driven whole-brain analyses revealed associations between PBA and white matter degeneration in descending corticobulbar as well as in commissural tracts. In our hypothesis-driven analyses, PBA was associated with increased right corticobulbar tract RD (p = 0.006) and decreased FA (p = 0.026). The left-hemispheric corticobulbar tract, as well as functional connectivity, showed similar tendencies. While uncorrected p-maps revealed both voxelwise and ROI trends for associations between PBA and cerebellar measures, these did not reach significance to unequivocally support the "cerebellar hypothesis".

CONCLUSIONS

Our data confirm associations between cortex-brainstem disconnection and the clinical severity of PBA. While our findings may be disease-specific, they are consistent with the classical cortico-medullary model of pseudobulbar affect.

Topographic Consideration on the Occurrence of Ipsilesional Facial Paresis in Lateral Medullary Infarction

INTRODUCTION

The purpose of this study was to identify course of the corticobulbar tract and factors associated with the occurrence of facial paresis (FP) in lateral medullary infarction (LMI).

METHODS

Patients diagnosed with LMI who were admitted to tertiary hospital were retrospectively investigated and divided into two groups based on the presence of FP. FP was defined as grade 2 or more by the House-Brackmann scale. Differences between the two groups were analyzed with respect to anatomical location of the lesions, demographic data (age, sex), risk factors (diabetes, hypertension, smoking, prior stroke, atrial fibrillation, and other cardiac risk factors for stroke), large vessel involvement on magnetic resonance angiography, other symptoms and signs (sensory symptoms, gait ataxia, limb ataxia, dizziness, Horner syndrome, hoarseness, dysphagia, dysarthria, nystagmus, nausea/vomiting, headache, neck pain, diplopia, and hiccup).

RESULTS

Among 44 LMI patients, 15 patients (34%) had FP, and all of them had ipsilesional central-type FP. The FP group tended to involve upper (p < 0.0001) and relative ventral (p = 0.019) part of the lateral medulla. Horizontally large lesion was also related to the presence of FP (p = 0.044). Dysphagia (p = 0.001), dysarthria (p = 0.003), and hiccups (p = 0.034) were more likely to be accompanied by FP. Otherwise, there were no significant differences.

CONCLUSION

The results of present study indicate that the corticobulbar fibers innervating the lower face decussate at the upper level of the medulla and ascend through the dorsolateral medulla, where the concentration of the fibers is densest near the nucleus ambiguus.

Bilateral medial medullary infarction with intravenous thrombolytic therapy: A case report

RATIONALE

Bilateral medial medullary infarction is a rare stroke subtype. To investigate its clinical manifestations, etiology, imaging features and thrombolytic effect, We here in reported a patient with acute ischemic stroke in the bilateral medial medullary and reviewed the related literatures.

PATIENTS CONCERN

A 64-year-old female was taken to our hospital after 4.5 hours of dizziness in the morning, followed by somnolence and limb weakness. She gradually worsened into a rapidly progressive tetraparesis and slurred speech.

DIAGNOSES

Diffusion weighted imaging exhibited a "heart appearance" sign in bilateral medial medulla oblongata, and high-resolution magnetic resonance imaging suggested the left vertebral artery-4 thromboembolism.

INTERVENTIONS

Timely intravenous thrombolysis was performed.

OUTCOME

After intravenous thrombolysis, the patient's symptoms did not worsen in a short time. Although the symptoms were aggravated in the later stage, they were alleviated after active treatment.

LESSONS

Diffusion weighted imaging can assist in the early diagnosis of bilateral medial medullary infarction, which will help in the decision to proceed with intravenous thrombolysis therapy. High-resolution magnetic resonance imaging should be improved as soon as possible, which can provide basis for the next intravascular interventional therapy.

Mixed Germ Cell Tumor with a Yolk Sac Tumor Component in the Medulla Oblongata of a 50-year-old Patient: A Case Report and Literature Review

Yolk sac tumor (YST) is a rare primary brain tumor that occurs almost exclusively in patients under 30 years old. Intracranial germ cell tumors are most frequently located in the pineal and suprasellar region. Medulla oblongata YSTs are particularly rare. Extragonadal YSTs may be difficult to diagnose because of their characteristics, such as the rarity and variety of growth patterns. Furthermore, they are known to have a very poor prognosis. We herein report a case of YST of the medulla oblongata in a 50-year-old woman. She was followed up for 18 months without any tumor recurrence.

Anatomic and MRI bases for medullary infarctions with patients' presentation

OBJECTIVE

There is a low incidence of the medullary infarctions and sparse data about the vascular territories, as well as a correlation among the anatomic, magnetic resonance imaging (MRI) and neurologic signs.

MATERIALS AND METHODS

Arteries of the 10 right and left sides of the brain stem were injected with India ink, fixed in formalin and microdissected. The enrolled 34 patients with medullary infarctions underwent a neurologic, MRI and Doppler examination.

RESULTS

Four types of the infarctions were distinguished according to the involved vascular territories. The isolated medial medullary infarctions (MMIs) were present in 14.7%. The complete MMIs comprised one bilateral infarction (2.9%), whilst the incomplete and partial MMIs were observed in 5.9% and 8.9%, respectively. The anterolateral infarctions (ALMIs) were very rare (2.9%). The complete and incomplete lateral infarctions (LMIs), noted in 35.3%, comprised 11.8% and 23.6%, respectively, that is, the anterior (5.9%), posterior (8.9%), deep (2.9%), and peripheral (5.9%). Dorsal ischemic lesions (DMIs) occurred in 11.8%, either as a complete (2.9%), or isolated lateral (5.9%) or medial infarctions (2.9%). The remaining ischemic regions belonged to various combined infarctions of the MMI, ALMI, LMI and DMI (35.3%). The infarctions most often affected the upper medulla (47.1%), middle (11.8%), or both (29.5%). Several motor and sensory signs were manifested following infarctions, including vestibular, cerebellar, ocular, sympathetic, respiratory and auditory symptoms.

CONCLUSIONS

There was a good correlation among the vascular territories, MRI ischemia features, and neurologic findings regarding the medullary infarctions.

[A Case of Bilateral Medial Medullary Infarction With Heart Appearance Sign]

We report a bilateral medial medullary infarction in which diffusion-weighted images revealed a unique configuration: a heart appearance sign. If it is early diagnosed, it might predict a poor outcome. An 85-year-old man developed dysarthria and numbness in his four limbs and was transferred to our hospital. Brain MR diffusion-weighted images revealed a high-intensity lesion in the bilateral medial medulla oblongata -- a heart appearance sign -- and we diagnosed a bilateral medial medullary infarction. Although his symptom changed aggressively for the worse, it finally changed for the better without bulbar paralysis, and he was transferred to another hospital for rehabilitation. When the medial medulla oblongata is supplied by the unilateral control of the anterior spinal artery, its occlusion can cause a bilateral medial medullary infarction.

CLINICAL AND IMAGING FEATURES OF MEDIAL MEDULLARY INFARCTION: RESULTS OF A PROSPECTIVE HOSPITAL-BASED COHORT STUDY ILLUSTRATED WITH A CASE REPORT IN A WHITE EUROPEAN ADULT

OBJECTIVE

The aim: This study aims in a prospective hospital-based cohort study to determine clinical and imaging features of medial medullary infarction and report a relevant clinical case in a white European adult.

PATIENTS AND METHODS

Materials and methods: We have prospectively enrolled one hundred twenty adult patients with acute posterior circulation stroke. All patients were admitted and enrolled in the study within 6 to 24 hours from the onset of the stroke symptoms. Study subjects were recruited from the hospital's wards and emergency departments from 2011 to 2020. Comprehensive clinical, MRI, ultrasound, and laboratory examinations were performed on all patients.

RESULTS

Results: 68 men and 52 women aged 28 to 89 years (average age 60.7 ± 12.1 years) with an acute ischemic posterior circulation stroke were enrolled in the study. Out of these 120 patients, 22 (18.3%) had acute medulla oblongata infarctions. Clinical and imaging features of medial medullary infarction are analyzed and illustrated with a clinical case presentation in a white European adult.

CONCLUSION

Conclusions: Specific features of medial medullary infarction were determined, analyzed, described, and illustrated with a clinical case.

LATERAL MEDULLARY INFARCTION: A PROSPECTIVE HOSPITAL-BASED COHORT STUDY OF CLINICAL AND IMAGING FEATURES AND A CASE REPORT IN A WHITE ADULT

OBJECTIVE

The aim: The purpose of this study is to determine clinical and imaging features of lateral medullary infarction in a prospective hospital-based cohort study, illustrated with a clinical case presentation in a white adult.

PATIENTS AND METHODS

Materials and methods: We prospectively recruited 120 acute posterior circulation stroke patients, admitted to the Neurological Center of the University Hospital (Oleksandrivska Clinical Hospital) in Kyiv, Ukraine, within 6 to 24 hours from the onset of the stroke symptoms. Comprehensive neurological, clinical, laboratory, ultrasound, and imaging examination was performed on all patients.

RESULTS

Results: Out of 120 adult patients (68 men, 52 women aged 28 to 89 years; average age 60.7 ± 12.1 years) with an acute ischemic MRI/CT-proven posterior circulation stroke, 22 (18.3%) patients have acute medulla oblongata infarctions.We provided a complex clinical, neurological, laboratory, and instrumental analysis of lateral medullary infarction illustrated with a clinical case presentation.

CONCLUSION

Conclusions: Specific clinical and imaging features of lateral medullary infarction were determined, analyzed, compared, and described.

Case of simultaneous Chiari 1.5 malformation and syringobulbia

Chiari 1.5 malformation (C1.5) is a rare condition characterized by caudal descent of the brain stem, together with descent of the cerebellar tonsils characteristic of Chiari I malformation (CIM). Syringobulbia (SB) is rarely associated with CIM and to date has not been reported in a patient with C1.5. An adolescent female presented with Valsalva-induced headaches and a left abducens nerve palsy. Imaging revealed C1.5 and a huge syringomyelia extending cranially into the herniated medulla oblongata as syringobulbia. Simultaneous cases of C1.5 and syringomyelia (SM) have been described, but, to our knowledge, this is the first reported case of simultaneous C1.5 and SB. As SB can have life altering consequences, the clinician should keep this possibility in their differential diagnosis.

[Blepharoptosis and dysarthria in a boy aged 2 years]

A boy, aged 2 years and 4 months, had a sudden onset of blepharoptosis of the right eyelid, accompanied by the mouth deviated to the right side, drinking cough, nystagmus, and developmental regression. Cranial MRI showed softening lesions formed after infarction of the right dorsolateral medulla oblongata, while head CT angiography showed no imaging of the proximal part of the V4 segment of the right vertebral artery. The child was diagnosed with dorsolateral medulla oblongata syndrome and was treated with gamma globulin to regulate immune function, with mannitol to reduce neuronal edema, with low-molecular-weight heparin sodium to improve local hypercoagulation of occluded blood vessels, with hyperbaric oxygen to improve local ischemia and hypoxia and promote the recovery of brain function, and with neuromuscular electrical stimulation to promote the recovery of neuromuscular function. Before discharge, only mild right ataxia and Horner syndrome remained. This article reports the first case of infantile dorsolateral medulla oblongata syndrome and provides experience for the diagnosis and treatment of the disease.

[Hemiplegia cruciata and severe facial pain due to infarction of the cervicomedullary junction: a case report]

We report the case of a 66-year-old female with hemiplegia cruciata and severe facial pain due to infarction of the cervicomedullary junction. She presented to the hospital with complaints of acute-onset left facial pain and gait disturbance. Neurological examination revealed narrow left palpebral fissure, severe left facial pain and hypothermoesthesia, weakness predominantly in the left upper and right lower extremities, decreased pain and temperature sensation in the right lower extremity, decreased vibration sensation in the left lower extremity, hyperreflexia in the left upper extremity, and mild ataxia in the left upper and lower extremities. Brain MRI revealed a high-intensity lesion in the left cervicomedullary junction on diffusion-weighted and fluid-attenuated inversion recovery images. Hemiplegia cruciata due to the pyramidal tract injury at the cervicomedullary junction is an uncommon clinical manifestation. However, in patients with hemiplegia cruciata, identifying the lesion location may be difficult. Clinicians should consider the possibility of pyramidal decussation lesions. Anatomical differences, in the course of pyramidal tract fibers between the upper and lower limbs have been considered in the pyramidal decussation. Hemiplegia cruciata in this case was primarily caused by the impairment of the left upper limb pyramidal fibers after the pyramidal decussation and the right lower limb pyramidal fibers before the pyramidal decussation.

[Bilateral Medial Medulla Infarction Mimicking Guillain-Barré Syndrome and its Variants]

A 70-year-old man presented with dizziness and unsteadiness when standing and was hospitalized in another hospital. Magnetic resonance imaging (MRI) of the brain on Day 1 showed no abnormalities. The patient developed respiratory failure on Day 1and flaccid tetraplegia on Day 3, and was transferred to our hospital. Progressive upper and lower limb weakness and bulbar symptoms suggested Guillain-Barré syndrome or its variant. Diffusion-weighted MRI on Day 6 disclosed high signal intensities in the bilateral medial portion of the medulla, and the patient was diagnosed with bilateral medial medulla infarction. Bilateral medial medulla infarction should be considered when a patient shows progressive tetraplegia, and bulbar palsy and follow-up MRI is important to confirm the diagnosis. (Received January 23, 2020; Accepted April 21, 2020; Published August 1, 2020).

Patient characteristics with negative diffusion-weighted imaging findings in acute lateral medullary infarction

BACKGROUND

Diffusion-weighted imaging (DWI) on magnetic resonance imaging (MRI) shows limited sensitivity in the acute-phase brainstem infarctions, including lateral medullary infarction (LMI), and the detailed characteristics of acute LMI patients with initially negative DWI-MRI findings have not been reported previously. Therefore, we aimed to investigate the differences in the backgrounds or symptoms of acute LMI patients with initially negative findings in standard axial DWI-MRI and those with positive findings.

METHODS

In this retrospective cohort study, we collected the data for 35 consecutive acute LMI patients who were hospitalized in our hospital from January 2011 to December 2018. Initial standard axial DWI-MRI was assessed, and the patients were divided into positive and negative groups. The characteristics of the two groups were compared, and the usefulness of additional thin-slice coronal DWI-MRI was also investigated.

RESULTS

Nine (26%) acute LMI patients were initially negative on standard axial DWI-MRI. The patients were independently associated with smoking history (78% vs. 23%, p = 0.021) and headache (78% vs. 31%, p = 0.046). Thin-slice coronal DWI-MRI showed positive findings in 50% of the patients with negative findings in standard axial DWI-MRI. All four patients with negative findings in both standard axial and thin-slice coronal DWI-MRI had smoking history and headache.

CONCLUSION

Smoking history and headache were associated with initial negative results in standard axial DWI-MRI in acute LMI. Additional thin-slice coronal DWI-MRI was sometimes useful in detecting acute LMI. Follow-up MRI is important for patients showing negative findings in initial DWI-MRI.

Upbeat vertical nystagmus after brain stem cavernoma resection: a rare case of nucleus intercalatus/nucleus of roller injury

INTRODUCTION

CNS cavernomas are a type of raspberry-shaped vascular malformations that are typically asymptomatic, but can result in haemorrhage, neurological injury, and seizures. Here, we present a rare case of a brainstem cavernoma that was surgically resected whereafter an upbeat nystagmus presented postoperatively.

CASE REPORT

A 42-year old man presented with sudden-onset nausea, vomiting, vertigo, blurred vision, marked imbalance and difficulty swallowing. Neurological evaluation showed bilateral ataxia, generalized hyperreflexia with left-sided predominance, predominantly horizontal gaze evoked nystagmus on right and left gaze, slight left labial asymmetry, uvula deviation to the right, and tongue deviation to the left. MRI demonstrated a 13-mm cavernoma with haemorrhage and oedema in the medulla oblongata. Surgery was performed via a minimal-invasive, midline approach. Complete excision was confirmed on postoperative MRI. The patient recovered well and became almost neurologically intact. However, he complained of mainly vertical oscillopsia. The videonystagmography revealed a new-onset spontaneous upbeat nystagmus in all gaze directions, not suppressed by fixation. An injury of the rarely described intercalatus nucleus/nucleus of Roller is thought to be the cause.

CONCLUSION

Upbeat nystagmus can be related to several lesions of the brainstem, including the medial longitudinal fasciculus, the pons, and the dorsal medulla. To our knowledge, this is the first case of an iatrogenic lesion of the nucleus intercalatus/nucleus of Roller resulting in an upbeat vertical nystagmus. For neurologists, it is important to be aware of the function of this nucleus for assessment of clinical manifestations due to lesions within this region.

Medulla Oblongata Hemorrhage and Reverse Takotsubo Cardiomyopathy

BACKGROUND

Acute brain injury with strong surges of adrenergic outflow has resulted in takotsubo cardiomyopathy, but there are surprisingly few reports of takotsubo cardiomyopathy after intracranial hemorrhage, and none have been described from hemorrhage within the brainstem.

RESULTS

We describe a patient with reverse and reversible cardiomyopathy following a hemorrhage in the lateral medulla oblongata. While it is limited in size, the location of the hemorrhage caused acute systolic failure with left ventricular ejection fraction of 27% and vasopressor requirement for cardiogenic shock and pulmonary edema. There was full recovery after 7 days.

METHODS

Detailed case report.

CONCLUSION

Hemorrhage into medulla oblongata pressor centers may result in acute, reversible, stress-induced cardiomyopathy, affirming the adrenergic origin of this condition.

The relationship between deep medullary veins score and the severity and distribution of intracranial microbleeds

Background

Microbleeds are frequently detected in normal elderly population, and their presence is associated with an increased risk of intracerebral hemorrhage, ischemic stroke and cognitive impairment. Previous histopathologic findings mainly focused on arteries and capillaries. Nevertheless, few studies investigated the relationship between venous disruption and microbleeds.

Objective

We aimed to evaluate the extent of venous disruption in vivo and assess the correlation between deep medullary veins (DMVs) disruption and the severity and distribution of intracranial microbleeds in patients with cerebral small vessel disease (cSVD).

Methods

We retrospectively reviewed the clinical, laboratory and imaging data of the patients admitted to our department who received brain MRI and presented with CSVD imaging markers. Susceptibility weighted imaging (SWI) phase images were used to observe characteristics of DMVs and derive a brain region-based DMVs visual score. SWI magnitude images were used to evaluate microbleeds. We recorded the number and distribution (lobar or deep or infratentorial) of microbleeds. One-way ANOVA and logistic-regression analysis were used to examine the association between the DMVs score and microbleeds.

Results

A total of 369 cSVD patients were analyzed, including 177 (48.0%) patients with microbleeds, among whom 81(45.8%) patients had 1–2 microbleeds and 96 (54.2%) patients had ≥3 microbleeds (extensive microbleeds). The patients' DMVs score ranged from 0 to18, with a median score of 8(6–12). Higher DMVs score was independently associated with extensive microbleeds (OR = 1.108, 95%Cl: 1.010–1.215, p = 0.03) after adjusting for gender, hypertension, hyperhomocysteinemia, Fazekas score and number of lacunas. According to the distribution, 38 (21.5%) patients were found with strict lobar microbleeds, while 139 (78.5%) patients had non-strict lobar microbleeds. Higher DMVs score was also independently associated with non-strict lobar microbleeds (OR = 1.106, 95% Cl: 1.019–1.200, p = 0.016) after adjusting for gender, hypertension, hyperhomocysteinemia, Fazekas score and number of lacunas. DMVs score was not associated with strict lobar microbleeds (p = 0.307).

Conclusion

DMVs disruption might be involved in the development of extensive microbleeds, especially non-strict lobar cerebral microbleeds.

•

Deep medullary veins disruption was associated with extensive microbleeds.

•

Deep medullary veins disruption was associated with non-strict lobar microbleeds.

•

Venous insufficiency may be one of the pathogenic mechanisms of microbleeds.

Central Sensitization in Knee Osteoarthritis: Relating Presurgical Brainstem Neuroimaging and PainDETECT-Based Patient Stratification to Arthroplasty Outcome

OBJECTIVE

The neural mechanisms of pain in knee osteoarthritis (OA) are not fully understood, and some patients have neuropathic-like pain associated with central sensitization. To address this, we undertook the present study in order to identify central sensitization using neuroimaging and PainDETECT and to relate it to postarthroplasty outcome.

METHODS

Patients awaiting arthroplasty underwent quantitative sensory testing, psychological assessment, and functional magnetic resonance imaging (fMRI). Neuroimaging (fMRI) was conducted during punctate stimulation (n = 24) and cold stimulation (n = 20) to the affected knee. The postoperative outcome was measured using the Oxford Knee Score, patient-reported moderate-to-severe long-term pain postarthroplasty, and a range of pain-related questionnaires.

RESULTS

Patients with neuropathic-like pain presurgery (identified using PainDETECT; n = 14) reported significantly higher pain in response to punctate stimuli and cold stimuli near the affected joint (P < 0.05). Neural activity in these patients, compared to those without neuropathic-like pain, was significantly lower in the rostral anterior cingulate cortex (P < 0.05) and higher in the rostral ventromedial medulla (RVM) during punctate stimulation (P < 0.05), with significant functional connectivity between these two areas (r = 0.49, P = 0.018). Preoperative neuropathic-like pain and higher neural activity in the RVM were associated with moderate-to-severe long-term pain after arthroplasty (P = 0.0356).

CONCLUSION

The psychophysical and neuroimaging data suggest that a subset of OA patients have centrally mediated pain sensitization. This was likely due to supraspinally mediated reductions in inhibition and increases in facilitation of nociceptive signaling, and was associated with a worse outcome following arthroplasty. The neurobiologic confirmation of central sensitization in patients with features of neuropathic pain, identified using PainDETECT, provides further support for the investigation of such bedside measures for patient stratification, to better predict postsurgical outcomes.

Subarachnoid Hemorrhage with Concurrent Dural and Perimedullary Arteriovenous Fistulas at Craniocervical Junction: Case Report and Literature Review

BACKGROUND

The association between a dural arteriovenous fistula (dAVF) and perimedullary arteriovenous fistula (AVF) is rarely observed at the craniocervical junction (CCJ). We present a case of subarachnoid hemorrhage (SAH) with concurrent dAVF and perimedullary AVF at the CCJ. Here, we describe the cause of bleeding and the process of determining whether it was a varix or an arterial aneurysm.

CASE DESCRIPTION

A 69-year-old man with SAH visited the emergency department. A dAVF at the CCJ was detected on digital subtraction angiography (DSA). However, after 3 weeks, when the DSA was repeated, a perimedullary AVF and varix were identified. We performed an endovascular treatment, but because the perimedullary AVF remained, we performed a direct surgery. The patient was discharged without weakness, but this left abducens nerve palsy remained.

CONCLUSIONS

In recent reports, SAH caused by concurrent dAVF and perimedullary AVF raised the possibility of an arterial aneurysm. However, in this case, the possibility of venous bleeding was high and a varix rather than an aneurysm was observed. On the basis of the reported cases, concurrent dAVF and perimedullary AVF at the CCJ is a "middle-flow arteriovenous shunt" that may induce a varix or an arterial aneurysm.

Testing the diagnostic accuracy of [18F]FDG-PET in discriminating spinal- and bulbar-onset amyotrophic lateral sclerosis

PURPOSE

The role for [18F]FDG-PET in supporting amyotrophic lateral sclerosis (ALS) diagnosis is not fully established. In this study, we aim at evaluating [18F]FDG-PET hypo- and hyper-metabolism patterns in spinal- and bulbar-onset ALS cases, at the single-subject level, testing the diagnostic value in discriminating the two conditions, and the correlations with core clinical symptoms severity.

METHODS

We included 95 probable-ALS patients with [18F]FDG-PET scan and clinical follow-up. [18F]FDG-PET images were analyzed with an optimized voxel-based-SPM method. The resulting single-subject SPM-t maps were used to: (a) assess brain regional hypo- and hyper-metabolism; (b) evaluate the accuracy of regional hypo- and hyper metabolism in discriminating spinal vs. bulbar-onset ALS; (c) perform correlation analysis with motor symptoms severity, as measured by ALS-FRS-R.

RESULTS

Primary motor cortex showed the most frequent hypo-metabolism in both spinal-onset (∼57%) and bulbar-onset (∼64%) ALS; hyper-metabolism was prevalent in the cerebellum in both spinal-onset (∼56.5%) and bulbar-onset (∼55.7%) ALS, and in the occipital cortex in bulbar-onset (∼62.5%) ALS. Regional hypo- and hyper-metabolism yielded a very low accuracy (AUC < 0.63) in discriminating spinal- vs. bulbar-onset ALS, as obtained from single-subject SPM-t-maps. Severity of motor symptoms correlated with hypo-metabolism in sensorimotor cortex in spinal-onset ALS, and with cerebellar hyper-metabolism in bulbar-onset ALS.

CONCLUSIONS

The high variability in regional hypo- and hyper-metabolism patterns, likely reflecting the heterogeneous pathology and clinical phenotypes, limits the diagnostic potential of [18F]FDG-PET in discriminating spinal and bulbar onset patients.

Sarcoidosis of the medulla oblongata causing intractable hiccoughs and numbness of extremities: A case report

RATIONALE

Sarcoidosis is a multisystem disorder characterized by noncaseating granulomas. The nervous system is involved in 5 to 16% of the patients. However, neurosarcoidosis in the medulla oblongata presenting as hiccough is remarkably rare.

PATIENT CONCERN

A 55-year-old female was admitted to our hospital suffering from intractable hiccough and progressive numbness of extremities.

DIAGNOSIS

The MR imaging revealed a circumscribed mass lesion located on the medulla oblongata. The mass was hyperintense on T2-weighted images and enhanced homogeneously with gadolinium-diethylenetriamine penta-acetic acid. The cerebrospinal fluid analysis showed a moderately elevated protein content and a significant lymphocytosis 86.5%. Electrocardiogram (ECG) showed complete atrioventricular block. Bilateral supraclavicular, hilar, and mediastinal lymphadenopathy was diagnosed in a CT scan. Transbranchial needle aspiration biopsy revealed noncaseating granuloma consisting of epithelioid cells, lymphocytes, and rare multinucleated giant cells which was consistent with sarcoidosis. The diagnosis of multisystemic sarcoidosis was made.

INTERVENTIONS AND OUTCOMES

The patient underwent a permanent pacemaker insertion, and was successfully treated with corticosteroids.

LESSONS

It is important to consider neurosarcoidosis in the differential diagnosis of intramedullary lesion, since a right recognition may lead to appropriate treatment with steroids and avoid needlessly extensive surgery.

Diffusion tensor imaging findings of the brainstem in subjects with tonsillar ectopia

We aimed to evaluate the differences between apparent diffusion coefficient (ADC), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) values obtained from different cranial sites in subjects with Chiari I Malformation (CM-I) and borderline tonsillar ectopia (BTE), and to determine correlations between diffusion tensor imaging (DTI) metrics and the severity of tonsillar ectopia. A total of 73 subjects with CM-I and BTE and 35 control underwent MRI and DTI. In our study, ADC values measured from the level of medulla oblongata and the RD values measured in middle cerebellar peduncles, thalamus, and globus pallidus were higher in CM-I patients than in controls. FA values at the medulla oblongata level and AD values at the medulla oblongata and pons level higher in patients with CM-I. ADC and AD values measured at the pons level were higher in BTE subjects than in controls. Compared with BTE, the CM-I subjects' ADC values at the medulla oblongata and AD values at the pons level were higher. In addition, FAs at the pons and medulla oblongata level were higher. At the medulla oblongata level, a positive correlation was observed between ADC and the size of tonsillar ectopia. AD and FA values measured at the level of medulla oblongata and pons were positively correlated with the size of tonsillar ectopia. These findings may be related to the severity of microstructural changes involving neuronal tracts at the brainstem level due to tonsillar ectopia. DTI may be useful in determining the extent of microstructural changes at the tissue level in subjects with tonsillar ectopia.

Low Retrosigmoid Infratonsillar Approach to Lateral Medullary Lesions

OBJECTIVE

In our study, we comprehensively detail the technique of the low retrosigmoid approach to the lateral medullary area, including the inferior cerebellar peduncle, postolivary sulcus, pontomedullary sulcus, and inferior olivary nucleus, as well as the lateral recess of the fourth ventricle.

METHODS

Four formalin-fixed, silicone-injected, cadaveric human heads were examined under the operating microscope to demonstrate pertinent descriptive anatomy using the low retrosigmoid approach in a stepwise manner. Clinical parameters of a patient with a lateral medullary lesion were reviewed retrospectively to describe preoperative and postoperative examination and surgical details of the approach to the lateral medulla.

RESULTS

The clinical case report describes a low retrosigmoid craniotomy performed to access the exiting points of cranial nerves IX (glossopharyngeal) and X (vagus), foramen of Luschka, inferior cerebellar peduncle (lateral medullary zone), postolivary sulcus, and olivary nucleus. The lesion was exposed using the inferior cerebellar peduncle and removed using standard microsurgical technique.

CONCLUSIONS

The lower retrosigmoid infratonsillar approach provides excellent exposure to medullary safe entry zones, including the transolivary, postolivary sulcus, pontomedullary sulcus, and lateral medullary (inferior cerebellar peduncle) zones, for removal of lesions in this area.

Lateral medullary infarction with similar features of Brown Sequard syndrome caused by vertebrobasilar dysplasia and Klippel-Feil syndrome: A case report

RATIONALE

Patients with Klippel-Feil syndrome (KFS) are always anomaly associated with vertebrobasilar dysplasia. That may present commonly as infarction of brainstem, medulla, and cerebellum. In this article, we reported a rare case of lateral medullary infarction (LMI) with similar features of Brown Sequard syndrome caused by vertebrobasilar dysplasia and KFS, and the 2 rare conditions that are causally related. The case is being reported because of its unusual and rare presentation.

PATIENT CONCERNS

A 38-year-old female presented with acute unsteadiness, along with a tendency to lean to the left side while walking or sitting, and paresthesia in the right lower limb and trunk, at 2 days before admission. She had no history of hypertension and diabetes, but had a 20 years history of neck pain and dizziness, which was related to head movement.

DIAGNOSES

Brown Sequard syndrome and a lesion of the left thoracic spinal cord were suspected initially. KFS was confirmed by the cervical magnetic resonance imaging (MRI) and computed tomographic angiography (CTA) results. Transcranial Doppler (TCD) results confirmed that there was a causal link between LMI and KFS.

INTERVENTIONS

The patient rejected the operation of stabilization of the cervical spine with fusion at appropriate levels.

OUTCOMES

No recurrence of stroke, but neck pain and dizziness remained after 6 months of discharge.

LESSONS

For such patients, the conventional treatment of cerebral infarction might be ineffective, but stabilization of the cervical spine with fusion at appropriate levels can successfully prevent further episodes of syncope and stroke.

Unusual Intraparenchymal Pontomedullary Epidermoid Cyst in a 2-Year-Old Child: A Case Report and Review of the Literature

BACKGROUND

Intrinsic brainstem epidermoid cysts are rare, benign, slow-growing lesions. Their eloquence precludes complete excision; however, subtotal resection often will result in prolonged or sometimes permanent relief of presenting symptoms and signs. We describe an unusual case and review the literature of this pathology in the pediatric population.

CASE DESCRIPTION

We report an intra-axial pontine epidermoid cyst in a 2-year-old girl who presented with developmental delay, multiple cranial nerve palsies, and pneumonia. Magnetic resonance imaging demonstrated an intrinsic pontine lesion with partial restricted diffusion and an enhancing plaque, the latter not typically seen in congenital lesions like epidermoid. However, gross surgical inspection and histopathology confirmed an epidermoid.

CONCLUSIONS

Our case, supported by the literature, shows that brain stem epidermoid cysts may have atypical radiologic characteristics and that near-total resection remains safe and can improve outcome.

Trigeminal autonomic cephalalgia as a presenting feature of Neuromyelitis Optica: "A rare combination of two uncommon disorders"

Neuromyelitis Optica (NMO) can have atypical presentations like hiccups, vomiting, etc. which is classically described as the area postrema syndrome. Here we report a case of a 39 year old male patient who presented with features of Trigeminal Autonomic Cephalalgia (TAC). MRI spine showed long segment myelitis. Diagnosis of NMO was confirmed by a positive Anti aquaporin 4 antibody assay. TACs are a rare group of headache disorders characterized by severe unilateral headache in the V1 distribution of the trigeminal nerve and autonomic symptoms. This presentation in NMO is hitherto unreported in literature.

Panmedullary edema with inferior olivary hypertrophy in bilateral medial medullary infarction

Bilateral medial medullary infarction (MMI) is a rare type of stroke with poor outcomes. Inferior olivary nucleus hypertrophy results from a pathologic lesion in the Guillain-Mollaret triangle. The relationship between inferior olivary nucleus hypertrophy and the medullary lesion is obscure. To the best of our knowledge, only 1 autopsy case with unilateral medial medullary infarction that was associated with ipsilateral inferior olivary nucleus hypertrophy has been reported. We describe a rare case with acute infarction in the bilateral medial medulla oblongata accompanied by subacute bilateral inferior olivary nucleus hypertrophy and panmedullary edema. The hypertrophy appeared to have been caused by local ischemic damage to the termination of the central tegmental tract at the bilateral inferior olivary nucleus.

Impaired blood-brain/spinal cord barrier in ALS patients

Vascular pathology, including blood-brain/spinal cord barrier (BBB/BSCB) alterations, has recently been recognized as a key factor possibly aggravating motor neuron damage, identifying a neurovascular disease signature for ALS. However, BBB/BSCB competence in sporadic ALS (SALS) is still undetermined. In this study, BBB/BSCB integrity in postmortem gray and white matter of medulla and spinal cord tissue from SALS patients and controls was investigated. Major findings include (1) endothelial cell damage and pericyte degeneration, (2) severe intra- and extracellular edema, (3) reduced CD31 and CD105 expressions in endothelium, (4) significant accumulation of perivascular collagen IV, and fibrin deposits (5) significantly increased microvascular density in lumbar spinal cord, (6) IgG microvascular leakage, (7) reduced tight junction and adhesion protein expressions. Microvascular barrier abnormalities determined in gray and white matter of the medulla, cervical, and lumbar spinal cord of SALS patients are novel findings. Pervasive barrier damage discovered in ALS may have implications for disease pathogenesis and progression, as well as for uncovering novel therapeutic targets.

Vertebral artery dissection presented as lateral medullary syndrome in a patient with migraine: a case report

PURPOSE

Migraine and artery dissection are both rare causes of ischemic stroke. The mechanism of migraine-related intracranial artery dissection is still unknown. It is proposed that the repeated attack of migraine would make the involved artery more vulnerable to tearing and lead to dissection.

CASE REPORT

We describe a 42-year-old female suffering from basilar-type migraine for more than 20 years. The patient complained severe dizziness with hyperventilation while watching television. Initially anxiety and migraine attack were impressed in the emergency room, but dizziness accompanied with dysarthria and dysphagia was noted later. After admission, lateral medullary syndrome was suspected after a detailed neurological examination, and a brain magnetic resonance image (MRI) revealed an acute infarction on the left lateral medulla oblongata, confirming the clinical diagnosis Furthermore, cerebral angiography revealed the left distal vertebral artery dissection. The patient was reluctant to use an anticoagulant; therefore aspirin was given for secondary stroke prevention and topiramate for migraine prophylaxis.

CONCLUSION

The exact mechanism of migraine-related intracranial artery dissection has yet to be proven, we propose that this may be caused by vessel wall edematous changes with repeated migraine attacks resulting in sudden or unusual stretching.

Acute and critical care management of a pediatric patient with medullo-cerebellar impaling

The authors present a child with an accidental cervical medullo-cerebellar impaling by an aluminum rod. Careful planning for safe removal of the rod as well as vigilant attention to early cardiac instability and flash neurogenic pulmonary edema were paramount to her successful recovery. This patient illustrates that it is possible to survive impaling of the brainstem but it requires both innovation and collaboration by multiple specialists across different departments. The value of well coordinated and collaborative neuro surgical intensive care is demonstrated in this young girl's nearly complete recovery from the accident.

Calcified pilocytic astrocytoma of the medulla mimicking a brainstem "stone"

Brainstem gliomas are a heterogeneous group of tumours commonly found in children, comprising about 10% of central nervous system tumours in paediatric patients, but less than 2% in adults. Pilocytic astrocytomas usually involve the midbrain and the medulla, and their surgical resection, when feasible, is generally curative. Thin calcifications can be normally found within low grade gliomas, but densely calcified pilocytic astrocytomas of the brainstem have been only rarely reported. We present the case of a young man presenting with a large brainstem calcification involving the medulla, which was subtotally resected using a posterior suboccipital approach. The definitive pathological diagnosis was calcified pilocytic astrocytoma.