scholarly journals Long distance retrograde degeneration of the retino-geniculo-cortical pathway in homonymous hemianopia

2019 ◽  
Author(s):  
Alekya P. Rajanala ◽  
Mohammad A. Shariati ◽  
Yaping Joyce Liao
Keyword(s):  
Optic Tract ◽  
Occipital Lobe ◽  
Visual Pathway ◽  
Wilcoxon Test ◽  
Homonymous Hemianopia ◽  
Long Distance ◽  
Retrograde Degeneration ◽  
Posterior Group ◽  
Objective Evidence ◽  
Anterior Group

AbstractLong-distance retrograde degeneration of the retino-geniculo-cortical pathway has been described in humans and animal models following injury to the brain. In this study, we used optical coherence tomography (OCT) to measure the severity and timing of retrograde degeneration after post-chiasmal visual pathway lesions in patients with homonymous hemianopia. We performed a retrospective study of 69 patients with homonymous hemianopia and analyzed high quality OCT macular ganglion cell complex (GCC) and retinal nerve fiber layer (RNFL). Patients with lesions involving the optic tract and thalamus were included in the anterior group, while patients with lesions of the occipital lobe were included in the posterior group. Statistical significance was determined using Mann-Whitney U test and Wilcoxon test. We found that in patients with homonymous hemianopia, those with anterior lesion exhibited earlier and more severe thinning compared with the posterior group. In fact, thinning can occur within 2 months after insult in the anterior group. Within 6 months of onset, the anterior group exhibited about 5 times more hemi-macular GCC thinning than those with acquired lesions of the posterior visual pathway (P = 0.0023). Although the severity of hemi-macular GCC thinning was different, the majority of hemi-macular thinning occurred within the first 6 months in both groups. Beyond 2 years, thinning in those with acquired anterior and posterior lesions was minimal, except in a small number of patients with multiple insults to the occipital lobe. In conclusion, using OCT, we measured the severity and rate of long-distance, retrograde degeneration in patients with homonymous hemianopia. Homonymous hemi-macular thinning after optic tract and thalamic injury was more severe and occurred earlier compared with thinning after occipital lobe insult via trans-synaptic degeneration. The presence of severe hemi-macular degeneration on OCT provides objective evidence that localizes the lesion to the post-chiasmal anterior visual pathway.

scholarly journals How lesions at different locations along the visual pathway influence pupillary reactions to chromatic stimuli

2021 ◽  
Author(s):  
Carina Kelbsch ◽  
Krunoslav Stingl ◽  
Ronja Jung ◽  
Melanie Kempf ◽  
Paul Richter ◽  
...  
Keyword(s):  
Visual Field ◽  
Optic Tract ◽  
Occipital Lobe ◽  
Visual Pathway ◽  
Visual Field Defects ◽  
Ischemic Optic Neuropathy ◽  
Low Intensity ◽  
Pupillary Responses ◽  
Patient Groups ◽  
Fundamental Research

Abstract Purpose To examine systematically how prechiasmal, chiasmal, and postchiasmal lesions along the visual pathway affect the respective pupillary responses to specific local monochromatic stimuli. Methods Chromatic pupil campimetry (CPC) was performed in three patient groups (10 subjects with status after anterior ischemic optic neuropathy, 6 with chiasmal lesions, and 12 with optic tract or occipital lobe lesions (tumor, ischemia)) using red, low-intensity red, and blue local stimuli within the central 30° visual field. Affected areas - as determined by visual field defects revealed using conventional static perimetry - were compared with non-affected areas. Outcome parameters were the relative maximal constriction amplitude (relMCA) and the latency to constriction onset of the pupillary responses. Results A statistically significant relMCA reduction was observed in the affected areas of postchiasmal lesions with red (p = 0.004) and low-intensity red stimulation (p = 0.001). RelMCA reduction in the affected areas seemed more pronounced for low-intensity red stimulation (46.5% mean reduction compared to non-affected areas; 36% for red stimulation), however statistically not significant. In prechiasmal lesions, a statistically significant latency prolongation could be demonstrated in the affected areas with low-intensity red stimulation (p = 0.015). Conclusion Our results indicate that the choice of stimulus characteristics is relevant in detecting defects in the pupillary pathway of impairment along the visual pathway, favoring red stimuli of low intensity over blue stimuli. Such knowledge opens the door for further fundamental research in pupillary pathways and is important for future clinical application of pupillography in neuro-ophthalmologic patients.

scholarly journals A Prospective Study of Posterior (Transpedicular) Approach versus Anterior (Transthoracic/Thoracoabdominal) Approach for Posttraumatic Compression Fracture of Thoracolumbar Vertebra in a Tertiary Care Center: Comparison of Clinical and Radiological Outcomes

2020 ◽  
Author(s):  
Rahul Varshney ◽  
Parthasarathi Datta ◽  
Pulak Deb ◽  
Santanu Ghosh
Keyword(s):  
Prospective Study ◽  
Posterior Approach ◽  
Spinal Injuries ◽  
Anterolateral Approach ◽  
Kyphotic Angle ◽  
Posterior Group ◽  
Thoracoabdominal Approach ◽  
A Prospective Study ◽  
Anterior Group

Abstract Objective The aim of this article was to analyze the clinical and radiological outcomes of transpedicular decompression (posterior approach) and anterolateral approach in patients with traumatic thoracolumbar spinal injuries. Methods  It was a prospective study of patients with fractures of dorsolumbar spine from December 2011 to December 2013. A total of 60 patients with traumatic spinal injuries were admitted during the study period (December 2011–2013), of which 51 cases were finally selected and taken for operations while 3 were eventually lost in follow-up. Twenty patients were operated by anterolateral approach, titanium mesh cage, and fixation with bicortical screws. Twenty-eight patients were treated with posterior approach and transpedicular screw fixation. Clinical and radiographic evaluations were performed on all 48 patients before and after surgery. Results There were 48 patients of thoracolumbar burst fractures with 40 male and 8 female patients. Range of follow-up was from 1 month to 20 months, with a mean of 7.4. Preoperatively in anterior group, 65% of the patients were bed ridden, 20% patients were able to walk with support, and 15% of the patients were able to walk without support. In posterior group, 78.57% patients were bed ridden, 10.71% were able to walk with support, and 10.71% patients were able to walk without support. Kyphotic angle changes were seen in 16 patients out of 18 in anterior group and 20 patients in posterior group out of 25. Out of 18 patients in anterior group, 14 showed reduction in kyphotic angle of 10 to 100 (improvement), with mean improvement of 4.070. In posterior group, 7 patients showed improvement of 10 to 80 (reduction in kyphotic angle) whereas 13 patients showed deterioration of 1 to 120. The mean improvement was 2.140 in 7 patients and mean deterioration was 4.920. No statistical difference was found (p > 0.05) regarding improvement in urinary incontinence during the follow-up period. Conclusion There are significant differences in anterior and posterior approaches in terms of clinical improvement. Compared with posterior approach, the anterolateral approach can reduce fusion segment and well maintain the kyphosis correction. The selection of treatment should be based on clinical and radiological findings, including neurological deficit.

scholarly journals Occipital Lobe Metastasis of Hepatocellular Carcinoma Presenting as Homonymous Hemianopia

2017 ◽  
Vol 58 (4) ◽  
pp. 488 ◽  
Author(s):  
Hye Jin Lee ◽  
Young Hee Maeng ◽  
Jinho Jeong ◽  
You-Nam Chung ◽  
Chang Sub Lee ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Occipital Lobe ◽  
Homonymous Hemianopia

scholarly journals Neuroanatomic correlates of visual hallucinations in poststroke hemianopic patients

Neurology ◽  
2020 ◽  
Vol 94 (18) ◽  
pp. e1885-e1891
Author(s):  
Fiora Martinelli ◽  
Céline Perez ◽  
Florent Caetta ◽  
Michaël Obadia ◽  
Julien Savatovsky ◽  
...  
Keyword(s):  
Visual Recognition ◽  
Striate Cortex ◽  
Clinical Care ◽  
Brain Lesion ◽  
Inverse Correlation ◽  
Occipital Lobe ◽  
Lesion Size ◽  
Homonymous Hemianopia ◽  
Small Lesion ◽  
Visual Hallucinations

ObjectivesHomonymous hemianopia (HH) is the most frequent visual-field defect after a stroke. Some of these patients also have visual hallucinations, the origin and frequency of which remain largely unknown. The aims of this work were to determine the occurrence of visual hallucinations among poststroke hemianopic patients in function of the location (Brodmann areas) of the brain lesion, as determined by MRI, and to study the neuroanatomic correlates of these hallucinations by nature, frequency, and type.MethodsOne hundred sixteen patients with HH who had had a stroke in the posterior region, including the occipital lobe, participated in the study. We evaluated the frequency and nature of visual hallucinations with the Questionnaire for Hallucinations in Homonymous Hemianopia. The volume of each patient's brain lesion was modeled in 3 dimensions.ResultsOf 116 patients with an HH from a cortical infarction, 85 were excluded due to confounding factors associated with hallucinations. In the final cohort of 31 patients matched for lesion location and etiology, 58% had experienced hallucinations. A significant inverse correlation between lesion size and the frequency of visual hallucinations emerged. The presence of visual hallucinations in poststroke hemianopic patients requires a relatively small lesion that includes, at the very least, loss of the striate cortex but that spares Brodmann area 19, 20, and 37.ConclusionOur results suggest that visual hallucinations might be due to complex interactions between damaged areas and intact areas of the visual cortex. We discuss these findings regarding models of perception and of visual recognition. Our results also have implications for the clinical care of patients with HH who have had a stroke.

scholarly journals Cardiovascular Adaptations to Four Months Training in Middle-Aged Amateur Long-Distance Skiers

Diagnostics ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 442 ◽  
Author(s):  
Natalia Grzebisz
Keyword(s):  
Minute Ventilation ◽  
Lactate Concentration ◽  
Wilcoxon Test ◽  
Mass Composition ◽  
Long Distance ◽  
Marathon Runners ◽  
Preparation Period ◽  
Cross Country ◽  
Body Mass Composition ◽  
The Impact

Cross-country skiing has a positive effect on health. However, without an individual, thoughtful, and professional plan, it can cause irreversible health problems from overload and injury. The impact of exercise on results is well understood within the group of professional athletes. However, this remains unknown within the group of amateur cross-country skiers and marathon runners—in particular, the impact of the summer preparation period in which training loads performed in the oxygen zone combined with resistance training dominate. The aim of this study was to assess changes in the cardiovascular capacity and body mass composition of male cross-country skiers in the preparation period of their macrocycle. Variables were analyzed using basic descriptive statistics: mean and standard deviation (SD). To compare the results from both measurements (initial and final) the paired Wilcoxon test was used. A statistically significant increase was noted in maximum oxygen uptake and maximum minute ventilation, and a decrease in body fat content, maximum lactate concentration and lactate threshold, and heart rate on anaerobic threshold. Research indicated that in the amateur group increases similar to those in top competitors were achieved in the parameters tested, but the initial level was often significantly lower.

scholarly journals Hemianopia and Features of Bálint Syndrome following Occipital Lobe Hemorrhage: Identification and Patient Understanding Have Aided Functional Improvement Years after Onset

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Nicola McDowell ◽  
Gordon N. Dutton
Keyword(s):  
Dorsal Stream ◽  
Visual Field Loss ◽  
Occipital Lobe ◽  
Visual Assessment ◽  
Active Management ◽  
Homonymous Hemianopia ◽  
Functional Improvement ◽  
Posterior Parietal ◽  
Eeg Recordings ◽  
The Impact

Introduction. Cerebral visual impairment (CVI) can present around birth or any time thereafter. Homonymous hemianopia is a common feature. The concept that functional improvement is unattainable augurs against active management. Dorsal stream dysfunction (or Bálint syndrome when severe) results from bilateral posterior parietal dysfunction but may go undetected, especially in children. Case Presentation. At 16 the patient suffered spontaneous left occipital lobe brain hemorrhage from a ruptured arteriovenous malformation. This was surgically excised. Short lived right upper limb intermittent jerking, with additional left sided weakness, ensued. Anomalous EEG recordings, with right-sided bias, arose from the posterior temporoparietal area. A right homonymous hemianopia was evident. During the ensuing 17 years she experienced multiple complex difficulties, until, at a lecture describing how to identify and support children with CVI, she realized she herself had many of the difficulties described. Visual assessment identified hemianopia and dorsal stream dysfunction. Discussion. Following identification, characterization, and explanation of the impact of her visual difficulties, she both gained greater awareness of her visual difficulties and their impact and developed a range of strategies leading to functional improvement of her visual field loss and amelioration of her dorsal stream dysfunction, with great improvement in quality of life.

scholarly journals Frontal Recess Cells in International Frontal Sinus Anatomy Classification (IFAC); Prevalence, Infection Incidence, and Relation to Frontal Sinus Infection in Chronic Sinusitis Patients

2022 ◽  
Author(s):  
Ahmed Abdelfattah Bayomy Nofal ◽  
Mohammad Waheed El-Anwar
Keyword(s):  
Infection Rate ◽  
Frontal Sinus ◽  
Sinus Surgery ◽  
High Infection Rate ◽  
Frontal Recess ◽  
Posterior Group ◽  
Significant Difference ◽  
High Infection ◽  
Medial Group ◽  
Anterior Group

AbstractFrontal recess cells have many types with different sizes, arrangement, and extend. It plays an important role in successful functional endoscopic sinus surgery (FESS) as most causes of failure are related to it. Outline the prevalence of the frontal recess cells, pathological incidence of each cell regarding to frontal sinus pathology. Prospective study on 100 consecutive patients (200 sides) complaining from nasal and sinus symptoms which did not respond to medical management and indicated for FESS. Anterior group was infected in 30.8%; agger nasi cell (ANC) present in 97% (25.8% infected, 74.2% not infected), supra agger cell (SAC) present in 48% (39.6% infected, 60.4% not infected), supra agger frontal cell (SAFC) present in 11% (36.4% infected, 63.6% not infected). Posterior group was infected in 24.8%; supra bulla cell (SBC) present in 72% (30.6% infected, 69.4% not infected), supra bulla frontal cell (SBFC) present in 23% (17.4% infected, 82.6% not infected), supra orbital ethmoid cell (SOEC) present in 42% of cases (19% infected, 81% not infected). Medial group [frontal septal cell (FSC)] was present in 21% (33.3% infected, 66.7% not infected). FSC, SAC, SAFC, and SBC showed high infection rate in association with infected frontal sinus, while, the SOEC, ANC, and SBFC did not have such high infection rate. Frontal recess cells show no difference in their prevalence either if the frontal sinus infected or not, however their infection rate show significant difference.

scholarly journals Congruous homonymous hemianopia due to occipital lobe infarction

2020 ◽  
pp. 105-109
Author(s):  
Suresh K ◽  
Arpita A ◽  
Sujitkumar S
Keyword(s):  
Occipital Lobe ◽  
Homonymous Hemianopia

Comparison of the results of 2 targeting methods in Gamma Knife surgery for trigeminal neuralgia

2008 ◽  
Vol 109 (Supplement) ◽  
pp. 185-189 ◽  
Author(s):  
Shinji Matsuda ◽  
Toru Serizawa ◽  
Osamu Nagano ◽  
Junichi Ono
Keyword(s):  
Complete Remission ◽  
Trigeminal Neuralgia ◽  
Gamma Knife ◽  
Pain Control ◽  
Gamma Knife Surgery ◽  
Root Entry Zone ◽  
Posterior Group ◽  
Anterior Group ◽  
Free Status

Object Gamma Knife surgery (GKS) is an effective treatment for intractable trigeminal neuralgia (TN). The authors compared results using two major GKS target points, the dorsal root entry zone and the retrogasserian portion, in a series of patients with intractable TN. Methods One hundred patients with medically refractory TN underwent GKS between August 1998 and December 2007. Thirty-seven were men, and 63 were women. The median age at GKS was 74 years. With a single isocenter and use of a 4mm collimator, 51 patients received 80 Gy at the proximal trigeminal nerve (posterior group) and 7 patients received 80 Gy, 1 patient received 85 Gy, and 41 patients received 90 Gy at the retrogasserian portion (anterior group). Follow-up was obtained by clinic visits every 3–6 months after GKS. Data on pain control, complications, and pain recurrence were recorded. The relationships between pain control status, complications, recurrence, and the target portions (anterior vs posterior) were analyzed. Results The median duration of follow-up was 30 months (range 3–88 months). Initially, 87 patients achieved pain-free status and 64 achieved complete remission. At the final follow-up visit, 68 patients were still in pain-free status and 42 were in complete remission. Recurrence of facial pain occurred in 15 patients. Forty-one patients developed some degree of trigeminal dysfunction. The rate of initial complete remission was higher in the posterior group than in the anterior group (p = 0.003). More complications were observed in the anterior group than in the posterior group (p = 0.009). Conclusions The posterior targeting group had better pain control and a lower complication rate. The authors recommend the posterior targeting method and use of 80 Gy for treatment of TN with GKS.

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