Pituitary adenoma presenting as isolated oculomotor nerve palsy.

Background: Isolated oculomotor nerve palsy is a relatively uncommon symptom of pituitary adenoma that usually occurs in association with pituitary apoplexy or cavernous sinus (CS) invasion. Case Description: We report two cases of relatively small pituitary adenomas with neither apoplexy nor CS invasion presenting as isolated oculomotor nerve palsy. Both patients presented with gradually worsening diplopia, without headache or visual field defects. Magnetic resonance imaging (MRI) showed a pituitary tumor with no evidence of intratumoral hemorrhage. Computed tomography revealed a lateroposterior extension of the tumor with the erosion of the posterior clinoid process. Constructive interference in steady-state MRI revealed compression of the oculomotor nerve by the tumor at the oculomotor triangle. The patients underwent endoscopic transsphenoidal surgery, and the intraoperative findings showed that the tumors did not invade the CS. The tumors were completely resected, and the oculomotor palsies resolved fully. Conclusion: These cases illustrate the need to consider isolated oculomotor nerve palsy as an initial manifestation of a relatively small pituitary adenoma with neither apoplexy nor CS invasion. Based on the characteristic radiological findings, early surgical treatment is recommended to preserve oculomotor function.

Order Space-Based Morphology for Color Image Processing.

Mathematical morphology is a fundamental tool based on order statistics for image processing, such as noise reduction, image enhancement and feature extraction, and is well-established for binary and grayscale images, whose pixels can be sorted by their pixel values, i.e., each pixel has a single number. On the other hand, each pixel in a color image has three numbers corresponding to three color channels, e.g., red (R), green (G) and blue (B) channels in an RGB color image. Therefore, it is difficult to sort color pixels uniquely. In this paper, we propose a method for unifying the orders of pixels sorted in each color channel separately, where we consider that a pixel exists in a three-dimensional space called order space, and derive a single order by a monotonically nondecreasing function defined on the order space. We also fuzzify the proposed order space-based morphological operations, and demonstrate the effectiveness of the proposed method by comparing with a state-of-the-art method based on hypergraph theory. The proposed method treats three orders of pixels sorted in respective color channels equally. Therefore, the proposed method is consistent with the conventional morphological operations for binary and grayscale images.

Concomitant Nephrotic Syndrome and Cryoglobulinemia in a Case of Malignant Mesothelioma.

Malignant pleural mesothelioma is rarely associated with nephrotic syndrome. Cryoglobulinemia is found in various pathological statuses, such as hepatitis C virus infection but rarely in malignant neoplasms. We recently encountered a patient with malignant mesothelioma coincident with nephrotic syndrome and cryoglobulinemia in the course of chemotherapy. A 60-year-old man employed as a building painter was diagnosed with malignant mesothelioma by lung biopsy two years earlier and was started on chemotherapy. Nivolumab seemed effective in controlling mesothelioma, but skin immune-related adverse events occurred during the course of treatment. After discontinuation of nivolumab and administration of gemcitabine as an alternative therapy, the patient was referred to a nephrologist because of the subsequent development of edema, renal injury, and proteinuria. Following the investigation, he was diagnosed with nephrotic syndrome and cryoglobulinemia with C4-dominant cold activation. However, a percutaneous renal biopsy could not be performed due to persistent severe cough induced by pleural involvement. The patient died a little over three years after the pathological diagnosis of pleural mesothelioma. Our case had three key features nephrotic syndrome was possibly associated with malignant mesothelioma; cryoglobulinemia occurred in malignant mesothelioma; and concomitant nephrotic syndrome and cryoglobulinemia occurred after chemotherapy. Unfortunately, our rare case lacks a basis in renal pathology or evidence of links between the pathogenesis of malignant mesothelioma, cryoglobulinemia, and nephrotic syndrome. This case does not provide a causal mechanism, but may be worth adding to the case list as one of the rare renal involvement in a patient with malignant mesothelioma.

Microsurgical Approach for True Posterior Communicating Artery Aneurysms: Literature Review and Illustrative Case.

True posterior communicating artery (PCoA) aneurysms are rare. Although true PCoA aneurysms have been reported to be located close to the internal carotid artery, at the middle part of PCoA, or close to the posterior cerebral artery; the best surgical approach to treat true PCoA aneurysms in each location remains unclear. We conducted a literature review using data from PubMed. Data on demographics, location, and projecting direction of the aneurysm, surgical approach, and surgical complications were collected. A total of 47 true PCoA aneurysms were included. Twenty-nine aneurysms originated from the proximal portion, 10 from the middle portion, and 6 from the distal portion; there were two giant aneurysms. The ipsilateral pterional approach was used for 37 true PCoA aneurysms (27 in proximal portion, 8 in middle portion, and 2 in distal portion of PCoA). The anterior temporal approach was used for two distal-portion aneurysms and one giant aneurysm. The anterior subtemporal approach was used for one distal-portion aneurysm. The subtemporal approach was used for two middle-portion aneurysms and one giant aneurysm. The contralateral pterional approach was used for two proximal-portion and one distal-portion aneurysms. Although most true PCoA aneurysms can be treated by the pterional approach, other means such as anterior temporal and subtemporal approaches can be applicable for aneurysms in the middle and distal portions of the PCoA or giant aneurysms. Surgeons should select an appropriate approach for each aneurysm while considering the advantages and disadvantages of each technique.

Local Contrast-Based Pixel Ordering for Exact Histogram Specification.

Histogram equalization is one of the basic image processing tasks for contrast enhancement, and its generalized version is histogram specification, which accepts arbitrary shapes of target histograms including uniform distributions for histogram equalization. It is well known that strictly ordered pixels in an image can be voted to any target histogram to achieve exact histogram specification. This paper proposes a method for ordering pixels in an image on the basis of the local contrast of each pixel, where a Gaussian filter without approximation is used to avoid the duplication of pixel values that disturbs the strict pixel ordering. The main idea of the proposed method is that the problem of pixel ordering is divided into small subproblems which can be solved separately, and then the results are merged into one sequence of all ordered pixels. Moreover, the proposed method is extended from grayscale images to color ones in a consistent manner. Experimental results show that the state-of-the-art histogram specification method occasionally produces false patterns, which are alleviated by the proposed method. Those results demonstrate the effectiveness of the proposed method for exact histogram specification.

POEMS Syndrome with Biclonal Gammopathy and Renal Involvement.

Polyneuropathy, Organomegaly, Endocrinopathy, M-protein and Skin changes (POEMS) syndrome manifests as elevated levels of vascular endothelial growth factor (VEGF) and monoclonal gammopathy. We treated a case of POEMS syndrome showing monoclonality in both IgA-λ and IgG-κ. Serial renal biopsies before treatment and after normalization of the VEGF levels suggested that glomerular microangiopathy had developed due to VEGF, while biclonal gammopathy was not eliminated. The renal pathology, proteinuria, and renal function all clearly improved. Although severe polyneuropathy limited activities of daily living and enforced a bedridden state, the patient dramatically regained his motor function, achieving crutch walking after induction of remission. This case is highly notable due to the presence of biclonality and repeated biopsies.

Hue-Preserving Saturation Improvement in RGB Color Cube.

This paper proposes a method for improving saturation in the context of hue-preserving color image enhancement. The proposed method handles colors in an RGB color space, which has the form of a cube, and enhances the contrast of a given image by histogram manipulation, such as histogram equalization and histogram specification, of the intensity image. Then, the color corresponding to a target intensity is determined in a hue-preserving manner, where a gamut problem should be taken into account. We first project any color onto a surface in the RGB color space, which bisects the RGB color cube, to increase the saturation without a gamut problem. Then, we adjust the intensity of the saturation-enhanced color to the target intensity given by the histogram manipulation. The experimental results demonstrate that the proposed method achieves higher saturation than that given by related methods for hue-preserving color image enhancement.

Case of de novo cerebral microbleeds in ischemic-type pediatric moyamoya disease.

BACKGROUND: Studies on pediatric patients with moyamoya disease who presented with de novo cerebral microbleeds (CMBs) are extremely rare. CASE DESCRIPTION: Herein, we report a 7-year-old boy with moyamoya disease who had de novo CMBs during treatment. He presented with transient left-side motor weakness and was diagnosed with moyamoya disease. He underwent revascularization surgery on the right cerebral hemisphere. Six months after the surgery, he presented with transient right-side motor weakness and MRA revealed progression of stenosis in the left middle cerebral artery. After another 3 months, three de novo CMBs were identified. He underwent revascularization surgery on the left side. The symptom disappeared completely after surgery and no additional de novo CMBs were identified 1 year after surgery. CONCLUSION: This is the first report on de novo CMBs in pediatric patients. Although the significance of de novo CMBs in pediatric patients is completely unknown, attention should be paid to not only ischemic stroke but also hemorrhagic stroke. Although the short-term course is good in the current case, follow-up period is too short to assess for rebleeding and long-term follow-up is still important. Further, more cases should be collected.

Elimination of the check-valve mechanism of the sacral Tarlov cyst using a rotation flap technique in a pediatric patient: technical note.

OBJECTIVE: Symptomatic Tarlov cysts in children are not sufficiently reported and treatment methods for Tarlov cysts are still controversial. The goal of this manuscript is to introduce a new variation of the surgical technique. METHODS: We performed surgery to eliminate the one-way check valve mechanism of the Tarlov cyst in a 7-year-old female who presented with urinary and fecal incontinence. A relatively large S3 nerve root cyst showed a one-way check valve on computed tomography myelography. The inlet of the check valve was enlarged with rotation flap reconstruction. RESULTS: Two months after surgery, the patient had established normal sphincter control. MRI performed two years later showed that the treated cyst was collapsing, and no recurrence occurred. CONCLUSIONS: Rotation flap enlargement of the check valve inlet is a safe and efficacious option for the treatment of pediatric patients with sacral Tarlov cysts.

A case of pediatric moyamoya disease with severe cerebral vasospasm and delayed cerebral infarction following an intraventricular hemorrhage.

Reports on patients with moyamoya disease presenting cerebral ischemic complications after the onset of intraventricular hemorrhage (IVH) and/or intracerebral hemorrhage (ICH) are limited. Herein, we report a case of a 7-year-old girl with moyamoya disease with severe cerebral vasospasm and delayed cerebral infarction following an IVH. Although the case is rare, the potential for vasospasm-induced cerebral infarction should be carefully considered and thus, intensive treatment should be immediately initiated.

Hemorrhagic stroke associated with essential thrombocythemia: Case report and literature review.

Hemorrhagic stroke associated with essential thrombocythemia (ET) is very infrequent. Herein, we report a case of a 33-year-old woman with a 2-year history of ET who developed intracerebral and subarachnoid hemorrhage. Angiography demonstrated severe vessel irregularity in the bilateral cerebral arteries. Molecular genetic testing revealed a calreticulin mutation. To our knowledge, hemorrhagic stroke has been reported in only six other patients with ET, and this is the first report of hemorrhagic stroke in an ET patient with a calreticulin mutation. We review the current literature and discuss the possible underlying mechanisms.

BMP4 induces asymmetric cell division in human glioma stem-like cells.

Glioblastoma (GBM) is a malignant tumor with a high recurrence rate and has very poor prognosis in humans. The median survival is still <2 years. Therefore, a new treatment strategy should be established. Recently, this cancer has been thought to be heterogeneous, consisting of cancer stem cells (CSCs) that are self-renewable, multipotent, and treatment resistant. So various strategies targeting glioma stem-like cells (GSCs) have been investigated. This study focused on strategies targeting GSCs through the induction of differentiation using bone morphogenetic protein 4 (BMP4). The expression of CD133, a cancer stem cell marker, under BMP4 treatment in GSCs was examined using flow cytometry, western blotting, and quantitative PCR. Immunofluorescent staining of GSCs was also performed to examine the type of cell division: asymmetric cell division (ACD) or symmetric cell division (SCD). We obtained the following results. The BMP4 treatment caused downregulation of CD133 expression. Moreover, it induced ACD in GSCs. While the ACD ratio was 23% without BMP4 treatment, it was 38% with BMP4 treatment (P=0.004). Furthermore, the tumor sphere assay demonstrated that BMP4 suppresses self-renewal ability. In conclusion, these findings may provide a new perspective on how BMP4 treatment reduces the tumorigenicity of GSCs.

Study of the Anatomical Features of the Offending Arteries Involved in Glossopharyngeal Neuralgia.

BACKGROUND: The anatomic features of the posterior inferior cerebellar arteries (PICAs) and the anterior inferior cerebellar arteries (AICAs) as offending arteries involved in glossopharyngeal neuralgia (GPN) are important to dictate the best surgical approach. OBJECTIVE: To study and classify the anatomic features of the offending arteries. METHODS: All clinical data and surgical videos from 18 GPN cases that were surgically treated during the past 10 yr were retrospectively reviewed. RESULTS: Among these 18 patients, the offending arteries involved were the PICA in 12 (66.7%), AICA in 4 (22.2%), and both PICA and AICA in 2 (11.1%). The PICA were then classified into the following groups based on their anatomic features: type I: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vestibulocochlear nerves; type II: the PICA formed an upward loop at the level of the glossopharyngeal nerve and passed between the glossopharyngeal and vagus nerves or between the rootlets of the vagus nerve; and type III: the PICA passed between the glossopharyngeal and vestibulocochlear nerves without forming a loop. The AICA had only one running pattern. CONCLUSION: The offending arteries involved in GPN, mainly the PICA and/or AICA, were classified into 4 different types based on their anatomic features.

Neugebauer Models for Color Error Diffusion Halftoning.

In this paper, we propose a method for halftoning color images based on an error diffusion technique, a color design criterion and Neugebauer models for expressing colors. For a natural extension of the conventional method for grayscale error diffusion to its color version, we first reformulate grayscale error diffusion with a one-dimensional Neugebauer model. Then we increase the dimension of the model to derive a color error diffusion method based on a three-dimensional Neugebauer model in RGB (red, green and blue) color space. Moreover, we propose a sparse Neugebauer model based on a color design criterion, or the minimal brightness variation criterion (MBVC), from which we derive a sparse Neugebauer model-based error diffusion method. Experimental results show that color halftone images produced by the proposed methods preserve the color contents in original continuous-tone images better than that by conventional color error diffusion methods. We also demonstrate that the proposed sparse method reduce halftone noise better than the state-of-the-art method based on MBVC.

Association between extracranial internal carotid artery tortuosity and thromboembolic complications during coil embolization of anterior circulation ruptured aneurysms.

BACKGROUND: The most frequent neurological complication during coil embolization of a ruptured cerebral aneurysm is a thromboembolic event. The association between the tortuosity of the internal carotid artery (ICA) and thromboembolic events (TEEs) during coil embolization of ruptured cerebral aneurysms remains unclear. The present study aimed to investigate the association between extracranial ICA tortuosity and thromboembolic complications during coil embolization of anterior circulation ruptured aneurysms. METHODS: A cohort of 57 patients with 57 anterior circulation ruptured aneurysms who underwent endovascular embolization at a single institution was retrospectively investigated. Patients were divided into two groups, those who experienced TEEs and those who did not that were compared and analyzed based on patient baseline characteristics, procedural factors, and anatomical factors including those of aneurysms and extracranial ICA tortuosity. The anatomical factors of the aneurysms included maximum dome size, neck width, dome-to-neck ratio, and dome-to-neck aspect ratio. Extracranial ICA angles in the proximal and distal curvature were evaluated as ICA tortuosity. RESULTS: Three of the 57 patients were excluded because of unavailability of data regarding ICA tortuosity; 54 patients were finally evaluated. TEEs occurred in six patients with five anterior cerebral and one internal carotid aneurysms. The extracranial distal ICA angle was significantly larger in patients with TEEs than in those without. Procedural factors and anatomical factors of the aneurysms were not associated with TEEs. CONCLUSIONS: Extracranial ICA tortuosity was significantly associated with an increased incidence of thromboembolic events during endovascular coiling of anterior circulation ruptured aneurysms.

Stabilization of vulnerable carotid plaques with proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, a novel class of monoclonal antibodies, reduce low-density lipoprotein cholesterol levels and improve outcomes of myocardial infarction and stroke. However, the effects of PCSK9 inhibitors on carotid plaques remain unclear. We describe three patients treated with PCSK9 inhibitor alirocumab for progressive carotid stenosis despite lipid-lowering statin therapy. All three patients had vulnerable plaques on magnetic resonance (MR) plaque imaging. After alirocumab treatment initiation, no patients suffered stroke or adverse events, and the stabilization of the carotid plaques was observed on MR plaque imaging.

Significance of simulated conventional images on dual energy CT after endovascular treatment for ischemic stroke.

BACKGROUND AND PURPOSE: CT scans often reveal post-interventional cerebral hyperdensities (PCHDs) immediately after intra-arterial thrombectomy (IAT) for ischemic stroke. Dual energy CT (DE-CT) can indicate whether PCHDs are caused by hemorrhage or iodinated contrast. Hyperdense lesions, detected on DE-CT with the use of iodinated contrast, could be associated with delayed hemorrhagic transformation and poor outcome. However, the quantitative indicators in DE-CT for predicting delayed hemorrhagic transformation remain unclear. We assessed such indicators for predicting delayed hemorrhagic transformation. MATERIAL AND METHODS: We retrospectively analyzed 52 consecutive acute ischemic stroke patients who underwent IAT. Simulated conventional CT (sCCT) images were obtained immediately after a DE-CT scan. Virtual, unenhanced, non-contrast (VNC) imaging was performed after reconstruction. Hounsfield units (HU) of the infarct areas observed on the sCCT were measured. The association of HU on sCCT with hemorrhage on VNC and delayed parenchymal hemorrhage (PH) was evaluated. RESULTS: The HU of sCCT with hemorrhage on VNC was significantly higher than without it (377.9±385 HU vs 83.5±37.9 HU; P<0.0001). The cut-off index was 80 HU, which displayed 100% sensitivity, 63.8% specificity, 22.3% positive predictive value, and 100% negative predictive value (P=0.0001, area under the curve (AUC)=0.89). The HU with delayed PH was substantially higher than without it (250.8±382.2 HU vs 93.7±64.8 HU; P=0.01). The cut-off index was 78 HU, which showed 100% sensitivity, 61% specificity, 25% positive predictive value, and 100% negative predictive value (P=0.049, AUC=0.76). CONCLUSION: sCCT images on DE-CT are useful for excluding intracerebral hemorrhage and delayed PH.

Possible involvement of pericytes in intraplaque hemorrhage of carotid artery stenosis.

OBJECTIVEIntraplaque hemorrhage (IPH) is most often caused by the rupture of neovessels; however, the factors of intraplaque neovessel vulnerability remain unclear. In this study, the authors focused on pericytes and aimed to investigate the relationship between IPH and pericytes.METHODSThe authors retrospectively analyzed the medical records of all patients with carotid artery stenoses who had undergone carotid endarterectomy at their hospitals between August 2008 and March 2016. Patients with carotid plaques that could be evaluated histopathologically were eligible for study inclusion. Intraplaque hemorrhage was analyzed using glycophorin A staining, and patients were divided into the following 2 groups based on the extent of granular staining: high IPH (positive staining area > 10%) and low IPH (positive staining area ≤ 10%). In addition, intraplaque neovessels were immunohistochemically evaluated using antibodies to CD34 as an endothelial cell marker or antibodies to NG2 and CD146 as pericyte markers. The relationship between IPH and pathology for intraplaque neovessels was investigated.RESULTSSeventy of 126 consecutive carotid stenoses were excluded due to the lack of a specimen for histopathological evaluation; therefore, 53 patients with 56 carotid artery stenoses were eligible for study inclusion. Among the 56 stenoses, 37 lesions had high IPH and 19 had low IPH. The number of CD34-positive neovessels was equivalent between the two groups. However, the densities of NG2- and CD146-positive neovessels were significantly lower in the high IPH group than in the low IPH group (5.7 ± 0.5 vs. 17.1 ± 2.4, p < 0.0001; 6.6 ± 0.8 vs. 18.4 ± 2.5, p < 0.0001, respectively).CONCLUSIONSPlaques with high IPH are associated with fewer pericytes in the intraplaque neovessels. This finding may help in the development of novel therapeutic strategies targeting pericytes.

A compact and facile microfluidic droplet creation device using a piezoelectric diaphragm micropump for droplet digital PCR platforms.

We have exploited a compact and facile microfluidic droplet creation device consisting of a poly(dimethylsiloxane) microfluidic chip possessing T-junction channel geometry, two inlet reservoirs, and one outlet reservoir, and a piezoelectric (PZT) diaphragm micropump with controller. Air was evacuated from the outlet reservoir using the PZT pump, reducing the pressure inside. The reduced pressure within the outlet reservoir pulled oil and aqueous solution preloaded in the inlet reservoirs into the microchannels, which then merged at the T-junction, successfully forming water-in-oil emulsion droplets at a rate of ∼1000 per second with minimal sample loss. We confirmed that the onset of droplet formation occurred immediately after turning on the pump (<1 s). Over repeated runs, droplet formation was highly reproducible, with droplet size purity (polydispersity, <4%) comparable to that achieved using other microfluidic droplet preparation techniques. We also demonstrated single-molecule PCR amplification in the created droplets, suggesting that the device could be used for effective droplet digital PCR platforms in most laboratories without requiring great expense, space, or time for acquiring technical skills.

Dural arteriovenous fistula manifesting as pontine hemorrhage at the craniocervical junction.

Craniocervical junction (CCJ) dural arteriovenous fistula (DAVF) manifesting as intracerebral hemorrhage is extremely rare. We report the first case of CCJ-DAVF manifesting as pontine hemorrhage. A 69-year-old male presented with a pontine hemorrhage manifesting as a sudden onset of right hemiparesis and dysarthria. Digital subtraction angiography revealed a CCJ-DAVF fed by the meningeal branches of the right vertebral artery. The patient underwent surgical ligation of the cerebral draining veins to prevent re-bleeding. The postoperative course was uneventful. The patient had no neurological deficit after 1 month rehabilitation.