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Background We aimed to establish a risk score system without radio-image examination, which could help clinicians to differentiate patients with vertigo and posterior circulation ischemia (PCI) rapidly from the other dizzy patients. Methods We analyzed 304 patients with vertigo (50% PCI). The attributes with more significant contributions were selected as the risk factors for the PCI risk score system, and every one of them was assigned a value according to their respective odds ratio values. We also compared the respective receiver operating characteristic curves of the 3 diagnostic methods (PCI score system, ABCD2, and Essen score systems) to evaluate their prediction effectiveness. Results Nine risk factors were ultimately selected for PCI score system, including high blood pressure (1′), diabetes mellitus (1′), ischemic stroke (1′), rotating and rocking (−1′), difficulty in speech (5′), tinnitus (−5′), limb and sensory deficit (5′), gait ataxia (1′), and limb ataxia (5′). According to their respective PCI risk scores, the patients were divided into 3 subgroups: low risk (≤0′, risk 95.0%). When 0′ was selected as a cutoff point for differentiating the patients with PCI from patients without PCI, the sensitivity was 94.1%, with a specificity of 41.4%. The areas under the receiver operator curve value of PCI score system was .82 (P = .000), much higher than the areas under the receiver operator curve value of ABCD2 (.69, P = .000) and that of the Essen system (.67, P = .000) Conclusion The PCI score system could help clinicians to differentiate patients with vertigo and PCI rapidly from the other dizzy patients.

Percheron infarction, arising from occlusion of the Artery of Percheron, is few, which can result in bilateral thalamic and mesencephalic infarctions. We herein showcase a confirmed case of the Percheron infarction at the admission day, in which the patient advanced into severe multiple posterior circulation infarcts, along with petechial hemorrhage within the infarcts, even given the right therapy without delay. It reminds us that whether we could or should take this special infarction as a forewarning of more harmful infarcts getting in the way, or at least a precaution of poor vessel condition.

Reversible cerebral vasoconstriction syndrome is characterized by thunderclap headache and multifocal cerebral vasoconstriction. Cerebral vasoconstriction is reversible, and most cases have good prognosis. However, clinical outcome is possibly severe when it is complicated by stroke, yet detailed reports on such a case are few. We experienced a case of severe reversible cerebral vasoconstriction syndrome in a 32-year-old woman with medical history of preeclampsia 3years prior. She presented with sudden sharp headache followed by altered mental status and vasoconstriction of the bilateral posterior cerebral arteries. She was treated with intravenous and oral calcium channel blockers, edaravone, and glycerol. However, the cerebral infarction in the posterior circulation subsequently remained, and her impaired consciousness did not recover. Furthermore, although imaging findings of vasoconstriction showed improvement a day after the occurrence of symptom, the same vessels showed poor visualization 7 weeks later, which indicated the recurrence of vasoconstriction, without additional symptom due to the fixed infarction. Although most cases of reversible cerebral vasoconstriction syndrome show good prognosis, neurologists must monitor the possibility of worse clinical course and permanent neurological deficit when associated with stroke, such as cerebral infarction. Strict management and treatment are needed in these cases.

Background The National Institutes of Health Stroke Scale (NIHSS) is the most widespread clinical scale used in patients presenting with acute stroke. The merits of the NIHSS include simplicity, quickness, and agreement between clinicians. The clinical evaluation on posterior circulation stroke remains still a limit of NIHSS. Methods We assessed the application of a new version of NIHSS, the e-NIHSS (expanded NIHSS), adding specific elements in existing items to explore signs/symptoms of a posterior circulation stroke. A total of 22 consecutive patients with suspected vertebrobasilar stroke were compared with 25 patients with anterior circulation stroke using NIHSS and e-NIHSS. Results We compared the NIHSS and e-NIHSS scores obtained by the 2 examiners, in patients with posterior circulation infarct (POCI), using the Wilcoxon test. Patients with POCI evaluated with e-NIHSS had an average of 2 points higher than patients evaluated with classical NIHSS. The difference was statistically significant ( P Conclusions The NIHSS is a practical scale model, with high reproducibility between trained, different examiners, focused on posterior circulation strokes, with the same total score and number of items of the existing NIHSS. The e-NHISS could improve the sensitivity of NIHSS in posterior circulation stroke and could have an impact on clinical trials, as well as on outcomes. Further studies are needed to investigate a larger number of patients and the correlation between the e-NIHSS score and neuroimaging findings.

Background Vertebral artery hypoplasia (VAH) is common, but its role in acute ischemic stroke (AIS) is uncertain. We aimed to evaluate the frequency, characteristics, and role of VAH in a large typical cohort of patients with AIS. Methods Up to 815 AIS patients (52.8% men, mean age 70 ± 14 years) were included in the study. All patients received a stroke work-up including brain imaging and duplex ultrasound. VAH was defined by a vessel diameter of less than or equal to 2.5 mm or a difference to the contralateral side of greater than 1:1.7. Vascular risk factors and stroke features were recorded. The subgroup of patients with posterior circulation AIS and magnetic resonance imaging was analyzed additionally, including the parameter of stroke extent. Results Up to 111 patients (13.6%) had VAH, with a mean diameter of 2.4 ± .4 mm. Patients with VAH were significantly younger ( P = .037) and more often male ( P = .033). There was no difference considering the National Institutes of Health Stroke Scale and modified Rankin Scale scores on admission or history of stroke. The distribution of patients without VAH was significantly different among the groups with anterior, posterior, and both circulations ischemia ( P = .009). In the group with posterior circulation stroke, 36 patients (20.9%) had VAH. There were no differences in age, sex, history of stroke, risk factors, vascular territory, stroke size, or etiology. VAH patients had less often embolic stroke patterns ( P = .009). Conclusions VAH is more common in patients with posterior circulation stroke and in younger patients. Apart from that, we found no clear evidence that VAH would be a predisposing factor for stroke or that it increased the risk for larger ischemic lesions in the posterior circulation.

Aphasia is one of the most common complications after stroke and occurs in 21-38% of the patients during acute period. The present study aimed to investigate the response to speech and language therapy according to artery involvement and lesion location in patients with post-stroke aphasia.The medical records of 107 patients with post-stroke aphasia (mean age, 58.8 ± 14.8 years) who were admitted to a single rehabilitation center for usual care after stroke were reviewed. Location of the ischemic lesion and involved artery was determined assessing the brain MRI of the patients. All the patients received 24 sessions speech and language therapy (3 days a week) as a part of 8-week rehabilitation program. Evaluation of the aphasia was performed with Gülhane Aphasia Test-2 (GAT-2) at baseline and at the end of the rehabilitation program.Baseline GAT-2 scores was significantly worse in patients with middle cerebral artery (MCA) involvement compared to patients with other artery involvements (p = 0.007). While the GAT-2 scores of patients with MCA involvement were improved significantly after speech and language therapy (p 0.001), the changes in those with anterior cerebral artery (ACA) and posterior cerebral artery (PCA) involvements were not significant (p 0.05).The present findings suggested that speech functions might be more affected in ischemic lesion of MCA and response to SLT might be better in patients with MCA involvement.

Background Susceptibility vessel sign (SVS) on susceptibility-weighted imaging (SWI) has a high sensitivity and specificity to detect the intra-arterial thrombus in anterior circulation stroke. However, SVS has not been evaluated in posterior circulation stroke. Methods We reviewed the data from patients with acute posterior cerebral artery (PCA) infarction within 24 hours from stroke onset. To elucidate the usefulness of SVS for the detection of intraluminal thrombus in acute PCA infarction, the frequency and location of SVS were compared with those of occlusion on magnetic resonance angiography (MRA) and hyperdense PCA sign on computed tomography (CT). Results Twenty-five patients with acute PCA infarction were enrolled in the study. The SVS was found in 92% (23 of 25). MRA showed occlusions in 64% (16 of 25). The SVS was identified in 100% (16 of 16) of patients with occlusion on MRA. Patients without occlusion on MRA also showed the SVS in 78% (7 of 9; P = .0233). The positive SVS without occlusion on MRA was mainly identified in patients with occlusion of distal branches of PCA; P3 segment in 4 and P4 segment in 3. However, the hyperdense PCA sign on CT showed in only 8% (2 of 25) of all patients; its sensitivity was significantly lower than those of the SVS on SWI ( P Conclusions SWI is more sensitive than MRA for the detection of intraluminal thrombus, especially peripheral one, in patients with acute ischemic stroke of the PCA territory. In addition, irrespective of thrombus location, SWI is significantly superior to CT in detecting thrombus in acute PCA infarction.

Background context Complications associated with C1 lateral mass screw placement are relatively infrequent. The most commonly feared complications include neural or vascular injury. Although both vertebral artery and internal carotid artery injuries have been discussed in the literature, there have been no reports of posterior inferior cerebellar artery (PICA) injury from C1 lateral mass screw placement. We report a case of patient who had a cerebellar stroke after C1 lateral mass screw placement, secondary to injury of an aberrant PICA. Purpose To describe the normal anatomy of the PICA, the anatomic variations previously reported in the literature, the sequela and symptoms of a patient with PICA injury, and the relevance to C1 lateral mass screw placement. No previous reports of PICA injury with a cerebellar stroke have been reported with C1 lateral mass screw instrumentation. Study design Case report and literature review. Methods The patient underwent an Occiput–C6 posterior instrumentation for a pathologic fracture, secondary to multiple myeloma. In the postoperative period, the patient was found to have dysarthria, imbalance, and dysdiadochokinesia. Urgent computed tomography confirmed well placed C1 lateral mass screws. Magnetic resonance imaging/Magnetic Resonance Angiography showed an infarct in the PICA distribution with an abnormal variant of the PICA coursing extracranially around C1. Neurologic monitoring did not detect the injury intraoperatively. Results The patient was treated with anticoagulation and he made a reasonable recovery from his stroke. Conclusions We report the first case of an aberrant PICA injured during a C1 lateral mass screw placement, resulting in a cerebellar stroke. Consideration should be given to abnormal PICA variation when placing C1 lateral mass screws.

Three-dimensional, black-blood, contrast-enhanced, T1-weighted magnetic resonance imaging (3D-BB-ceT1-MRI) could play a role in detection of thrombi and symptomatic intracranial atherosclerotic stenosis. We investigated the role of 3D-BB-ceT1-MRI in patients with acute ischemic stroke in the posterior circulation, and compared our findings with those from susceptibility-weighted imaging (SWI).We retrospectively reviewed 3D-BB-ceT1-MRI for patients between January 2017 and August 2018 with acute ischemic symptoms in the posterior circulation. During this period, 199 patients with acute infarction in the posterior circulation were enrolled. Time-of-flight-magnetic resonance angiography or cerebral angiography was used as the reference standard.Of these 199 patients, 47 had vessel occlusion associated with acute infarction. The sensitivity of 3D-BB-ceT1-MRI for detection of vessel occlusion was significantly higher than that of SWI (95.7% versus 53.2%, P.001). Twenty-one lesions with strong enhancement on 3D-BB-ceT1-MRI showed a negative susceptibility vessel sign (SVS) on SWI.3D-BB-ceT1-MRI showed strong enhancement (due to contrast stagnation) in the intra-arterial thrombi of patients with acute infarction in the posterior circulation. 3D-BB-ceT1-MRI had higher sensitivity than that of an SVS on SWI for detection of intra-arterial thrombi.

Background The Oxfordshire Community Stroke Project (OCSP) classification is a simple tool to categorize clinical stroke syndromes. We compared the outcomes of stroke patients after intravenous thrombolysis stratified by the baseline National Institutes of Health Stroke Scale (NIHSS) score or by the OCSP classification. Methods We assessed the safety of thrombolysis in consecutive stroke patients who received intravenous thrombolysis within 3 h after onset. The patients were grouped by the NIHSS score into mild to moderate stroke (≤ 20) and severe stroke (> 20), and also by the OCSP classification as having total anterior circulation infarcts (TACI), partial anterior circulation infarcts (PACI), posterior circulation infarcts (POCI), or lacunar infarcts (LACI). Symptomatic intracerebral hemorrhage (SICH) was used as the primary outcome. Results Of the 145 patients included in the study, 45 had a baseline NIHSS score > 20. Their stroke syndromes were as follows: 78 with TACI, 29 with PACI, 16 with POCI, and 22 with LACI. The proportion of SICH was comparable between patients with high or low NIHSS score (11.1% vs. 9.0%, P = 0.690). The chance of SICH was highest in patients with TACI (15.4%), followed by LACI (4.5%), PACI (3.4%), and POCI (0%). After adjustment for age, baseline glucose, and use of antiplatelet agents before admission, SICH was significantly increased in patients with TACI relative to those with non-TACI (odds ratio 5.92; 95% confidence interval 1.24–28.33, P = 0.026). Conclusions The OCSP clinical classification may help clinicians evaluate the risk of SICH following intravenous thrombolysis.

Cognitive decline following posterior cerebral artery infarction (PCAI) is associated with lesions in the occipital lobe that extend into the parahippocampus or the splenium. We investigated patterns of neuropsychological deficits, including those causing executive dysfunction, associated with isolated lesions of the occipital lobe and with extensive lesions of the occipital lobe that extended into the splenium or the posterior ventral temporal lobes including the parahippocampus and fusiform gyrus. Eleven patients with unilateral PCAI involving the cerebral cortex and one patient with an occipital hemorrhage were selected for inclusion in this study. The mean age of the patients was 68.50 ± 7.94 years and their mean level of education was 8.58 ± 4.12 years. Four patients had isolated occipital lobe lesions and eight had lesions in either the splenium or the posterior ventral temporal lobe in addition to the occipital lobe. Whereas three of four patients with isolated occipital lobe lesions had left-sided lesions, only three of the eight patients with extended occipital lesions had left-sided lesions. The patients underwent a standardized battery of neuropsychological tests. The patients with occipital injuries in addition to splenial or posterior ventral temporal lobe injuries demonstrated performance decline across diverse cognitive domains, including memory (eight of eight), visuospatial function (eight of eight), executive function (seven of eight), language-related function (four of eight) and attention (one of eight). In contrast, memory impairment (three of four patients) was the only area in which patients with isolated occipital lobe lesions demonstrated decline in performance. Our findings suggest that strokes in the territory of the posterior cerebral artery are frequently associated with executive dysfunction. Injuries involving the splenium or posterior ventral temporal lobe in addition to the occipital lobe lead to more diverse neuropsychological impairments than do isolated occipital lobe injuries alone.

Introduction Inner ear decompression sickness following scuba diving is not uncommon and the characteristic features of this disorder are acute peripheral vestibular syndrome, sometimes associated with cochlear signs, requiring urgent hyperbaric oxygen therapy. Cerebellar infarction can also mimic isolated peripheral vestibulopathy. Case report The authors report the case of a 47-year-old man in good general health admitted with acute left vestibular dysfunction suggestive of inner ear decompression sickness 6 hours after scuba diving. Normal videonystagmography and delayed onset of occipital headache finally led to brain MRI that confirmed the presence of recent ischaemic infarction in the territory of the medial branch of the posterior inferior cerebellar artery. Complementary investigations revealed the presence of a patent foramen ovale with atrial septal aneurysm. No underlying atherosclerotic disease or clotting abnormalities were observed. Discussion/Conclusion Cerebellar infarction can present clinically with features of inner ear decompression sickness following scuba diving. An underlying air embolism mechanism cannot be excluded, particularly in patients with a large right-to-left circulatory shunt and no other cardiovascular risk factors.

Background Magnetic resonance (MR) imaging of posterior cerebral artery infarction with hemiparesis (PCAH) is limited to case reports with T2-weighted lesions involving the cerebral peduncle. Objective We sought to extend the MR imaging correlate of PCAH. Methods The case histories and MR/MR angiography findings of 4 patients with PCAH were examined. Results Distinct from previously described MR imaging findings with PCAH, diffusion-weighted imaging and/or FLAIR changes were noted in the thalamogeniculate artery (TGA) territory in one patient; in the distribution of the TGA and lateral posterior choroidal artery (PChA) in two patients; and in the TGA and lateral PChA combined with the peduncular perforating arteries of the cerebral peduncle in one patient. Conclusion Diffusion-weighted imaging changes of infarction in the distribution of the TGA alone or combined with lateral PChA involvement with or without cerebral peduncle infarction correlate with PCAH.

The aim of this study was to evaluate the relationship between the cisternal segment of the oculomotor nerve and the posterior cerebral artery and its branches. The oculomotor nerve and the posterior cerebral artery of 15 cadaver brains (30 hemispheres) were examined using a surgical microscope. The dorsal portion of the cisternal segment of the oculomotor nerve had a close relationship with the P(1) and P(2) segments of the posterior cerebral artery in 100% of cases, the thalamoperforating arteries in 97%, the collicular arteries in 97%, the short circumferential arteries in 33% and the posterior medial choroidal arteries in 20%. The proximal portion of the nerve had a close relationship with the P(1) segment of the posterior cerebral artery, the thalamoperforating arteries, the collicular arteries and the short circumferential arteries, whereas the distal portion had a close relationship with the P(2) segment of the posterior cerebral artery and the posterior medial choroidal arteries. The oculomotor nerve was perforated by various arteries in different portions. These arteries were the thalamoperforating arteries in 10% of the hemispheres, the collicular arteries in 16% and the short circumferential arteries in 11%. It can be concluded that the dorsal portion of the cisternal segment of the oculomotor nerve has a close relationship with the branches arising from the P(1) and P(2) segments of the posterior cerebral artery. These arteries supply the cisternal segment of the oculomotor nerve.

Data from randomized therapeutic trials often provide little relevant evidence for therapeutic decisions physicians make daily. By illustrating the nuances of these four complex cases involving cerebrovascular disease, the authors stress the importance of more time spent by specialists at the bed-side, exploring patients' symptoms and learning their thoughts, fears, biases, and wishes.

Alexia without agraphia, or “pure” alexia, is an acquired impairment in reading that leaves writing skills intact. Repetition priming for visually presented words is diminished in pure alexia. However, it is not possible to verify whether this priming deficit is modality-specific or modality independent because reading abilities are compromised. Hence, auditory repetition priming was assessed with lexical decision and word stem completion tasks in pure alexic patients with lesions in left inferior temporal–occipital cortex and the splenium. Perceptually based, modality-specific priming models predict intact auditory priming, since auditory association cortex is spared in the patients. Alternatively, modality-independent models, which suggest that priming reflects the temporary modification of an amodal system, might predict impairments. Baseline performance was matched in the patients and controls, although lexical decision priming measures showed an interaction between group and repetition lag. The patients showed intact immediate priming but significantly less priming than controls at longer delays. Furthermore, word stem completion priming was abolished in the patients. One explanation for the deficit is that left inferior temporal–occipital cortex supports amodal aspects of priming, as suggested by recent neuroimaging results. Another possibility is that long-term auditory priming relies on covert orthographic representations which were unavailable in the patients. The results provide support for interactive models of word identification.

In cases of unilateral posterior cerebral artery (PCA) infarction, abnormal visual perception in the ipsilateral visual field, which is usually believed to be intact, is not met frequently and may confuse doctors during evaluation. Recently, we observed two patients who presented with contralateral hemianopsia accompanied by ipsilateral visual illusions after acute unilateral PCA infarctions. Their visual illusion was characterized by zooming in, macropsia or micropsia. These symptoms appeared to be related to deficits in size constancy. Lesions of both patients commonly involved the ipsilateral forceps major. The consistent presentation observed in these two patients suggests that dominance of size constancy can be located in the left hemisphere in some individuals.

We report a single-case study of peripherally acquired dyslexia that meets the clinical criteria of “alexia without agraphia.” The patient, AA, has a large infarct involving the left posterior cerebral artery. The most striking feature is a severe impairment in recognizing single visually presented letters that precludes explicit or implicit access to reading, even in a letter-by-letter fashion. AA can, however, differentiate letters from similar nonsense characters and digits, and he is also able to identify alphanumeric signs when the visual channel is bypassed (through somesthesic or kinesthesic presentation). Spelling tasks are also well performed. Since there is a breakdown in mapping a visually presented letter to its abstract graphemic representation, we propose the term “visuographemic alexia” for this kind of reading disorder. The pattern of deficits is interpreted following theoretical models previously developed in cognitive neuropsychology. An alexia for arabic numerals with preserved comprehension lends additional support for the crucial processing of different notational systems (e.g., phonographic vs logographic). More general perceptive disorders do not seem to account for these patterns; they are material-specific. Finally, we attempt to specify functional correlations with the implied neural networks.

Extrastriate area V4 is crucial for intermediate form vision and visual attention in nonhuman primates. Human neuroimaging suggests that an area in the lingual sulcus/fusiform gyrus may correspond to ventral V4 (V4v). We studied a human neurological patient, AR, with a putative V4v lesion. The lesion does not affect early visual processing (luminance, orientation, and motion perception). However, it does impair hue perception, intermediate form vision, and visual attention in the upper contralateral visual field. Form deficits occur during discrimination of illusory borders, Glass patterns, curvature, and non-Cartesian patterns. Attention deficits occur during discrimination of the relative positions of object parts, detection of low-salience targets, and orientation discrimination in the presence of distractors. This pattern of deficits is consistent with the known properties of area V4 in nonhuman primates, indicating that AR's lesion affects a cortical region functionally homologous to macaque V4.

The pre-motor theory of attention suggests that the mechanisms involved in target selection for eye movements are the same as those for spatial attention shifts. The pre-saccadic facilitation of perceptual discrimination at the location of a saccadic goal (paradigm of Deubel and Schneider, 1996) has been considered as an argument for this theory. We compared letter discrimination performance in a saccade (overt attention - pre-saccadic facilitation) and a fixation (covert attention) task in a patient with right posterior parietal damage and 4 controls. In the overt attention condition, the patient was instructed by a central cue to make a saccade to a target located at a peripheral location. During the saccade latency (in a period of time of 250 msec following the presentation of the cue), a letter was presented at the target location. Accuracy of leftward saccades was impaired compared to rightward saccades. To evaluate letter discrimination performance in this saccade task (i.e., the presence of pre-saccadic facilitation), we selected only those leftward saccades that were equivalent in accuracy (and latency) to the rightward ones. Within these selected trials, the patient was able to discriminate letters equally well in both visual fields. In contrast, he performed at chance level during the fixation task (covert attention condition) for letters presented at the same peripheral location with the same timing with respect to the cue presentation. The patient could thus discriminate the letter presented at 8° of visual eccentricity while he was preparing a saccade, whereas he was unable to perceive the letter in the fixation task. Remarkably, in the left visual field, letter discrimination was impossible even when a letter was presented as close as 2.5° of visual eccentricity in the fixation task. Altogether, these results suggest that pre-saccadic perceptual facilitation does not rely on the same processes as those of covert attention, as tested by fixation task. Instead, we propose that pre-saccadic perceptual facilitation results from a form of attention specific to action, which could correspond to a pre-saccadic remapping process.

Although essential thrombocythemia (ET) may involve thrombotic complications, including arterial or venous thrombosis, there are no reports of major vascular complications, including both arterial and venous thrombosis, in a patient with ET. We report on a patient with a cerebral infarction affecting the right lateral thalamus and a stenotic lesion of the right posterior cerebral artery. This arterial thrombotic event may be related to ET, which was based on results of a bone marrow biopsy specimen. The patient had experienced previous events of thrombosis, splenic infarction with venous thrombosis, and myocardial infarction. The cause of recurrent ischemic events involving both arterial and venous systems may be sustained elevation of platelet counts. Previous thrombosis is an established risk factor for rethrombosis in patients with ET. Efficient cytoreductive therapy with an antiplatelet agent should be considered for the prevention of recurrent thrombosis.