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This paper presents a follow-up of a child with Balint's syndrome over more than a decade. The patient experienced traumatic brain injury before age 12, resulting in bilateral occipito-parietal infarctions and a clinical presentation of Balint's syndrome. Neuropsychological assessments at three time points showed average verbal abilities alongside persistent difficulties in visual orientation, mirrored in the patient's daily life. Her outstanding compensatory abilities in the face of these impairments are discussed with respect to the recruitment of the ventral visual stream and the role of top-down processing. This profile may help to determine interventions for younger patients with similar lesions.

Injury to the primary visual cortex (V1, striate cortex) and the geniculostriate pathway in adults results in cortical blindness, abolishing conscious visual perception. Early studies by Larry Weiskrantz and colleagues demonstrated that some patients with an occipital-lobe injury exhibited a degree of unconscious vision and visually-guided behaviour within the blind field. A more recent focus has been the observed phenomenon whereby early-life injury to V1 often results in the preservation of visual perception in both monkeys and humans. These findings initiated a concerted effort on multiple fronts, including nonhuman primate studies, to uncover the neural substrate/s of the spared conscious vision. In both adult and early-life cases of V1 injury, evidence suggests the involvement of the Middle Temporal area (MT) of the extrastriate visual cortex, which is an integral component area of the dorsal stream and is also associated with visually-guided behaviors. Because of the limited number of early-life V1 injury cases for humans, the outstanding question in the field is what secondary visual pathways are responsible for this extraordinary capacity? Here we report for the first time a case of a child (B.I.) who suffered a bilateral occipital-lobe injury in the first two weeks postnatally due to medium-chain acyl-Co-A dehydrogenase deficiency. At 6 years of age, B.I. underwent a battery of neurophysiological tests, as well as structural and diffusion MRI and ophthalmic examination at 7 years. Despite the extensive bilateral occipital cortical damage, B.I. has extensive conscious visual abilities, is not blind, and can use vision to navigate his environment. Furthermore, unlike blindsight patients, he can readily and consciously identify happy and neutral faces and colors, tasks associated with ventral stream processing. These findings suggest significant re-routing of visual information. To identify the putative visual pathway/s responsible for this ability, MRI tractography of secondary visual pathways connecting MT with the lateral geniculate nucleus (LGN) and the inferior pulvinar (PI) were analysed. Results revealed an increased PI-MT pathway in the left hemisphere, suggesting that this pulvinar relay could be the neural pathway affording the preserved visual capacity following an early-life lesion of V1. These findings corroborate anatomical evidence from monkeys showing an enhanced PI-MT pathway following an early-life lesion of V1, compared to adults., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This pilot study aimed to evaluate the clinical efficacy and feasibility of a fluidised positioning device to reduce occipital pressure injuries (PIs). A post-test design with a historical control group was used in a 54-bed intensive care unit between September 2017 and August 2018. Patients who were receiving either extracorporeal membrane oxygenation, were mechanically ventilated, or had raised intracranial pressure (≥20) were recruited. The intervention consisted of a fluidised positioning device under the patient's head, and a skin assessment every 8 h. Outcome measures included the occurrence of occipital PIs and registered nurses (RNs)' perspectives of the intervention. Data collected from patients in the intervention group were compared with data obtained from the historical control group between May 2016 and April 2017. Sixty-four patients were recruited in the intervention phase and 63 were in the historical control group. Results showed a statistically significant reduction in occipital PIs by 87.7% (16/63; 25.4% historical control vs 2/64; 3.13% interventional group). Bedside RNs provided positive evaluation of the fluidised positioning device. The findings demonstrate that the fluidised positioning device is a feasible and effective intervention in reducing the risk of occipital PIs in intensive care patients, which merits the continuation of use and further evaluation through a larger-scale study., (© 2018 Medicalhelplines.com Inc and John Wiley & Sons Ltd.)

Objectives: Falls are commonly reported in children who present with both accidental and inflicted brain injuries. Short falls rarely result in serious or life-threatening injuries. Our purpose is to describe a series of cases of short falls with occipital impact leading to subdural hemorrhage (SDH)., Methods: We present a series of 8 witnessed accounts of young children diagnosed as having SDHs after striking the back of their heads during a short fall. Child-abuse physicians were surveyed to determine if they had evaluated a child younger than 24 months diagnosed as having SDH, with or without retinal hemorrhages, following a witnessed fall with occipital impact. Submitted cases were analyzed., Results: The median age of the children was 12.5 months. All fell backward from a standing or seated position onto a hard surface and immediately developed symptoms. There was an average of 4 witnesses per case. Physical examinations were normal; however, the majority of children had enlarged head circumferences. All were previously healthy. Six of 8 children had unilateral convexity SDH. All children had varying degrees of retinal hemorrhage but no retinoschisis. The majority of children had returned to their baseline within 24 hours of hospitalization., Conclusions: Although a larger study is needed to identify the full spectrum of injuries, we postulate that, if a history of a fall with an occipital impact is elicited during a trauma workup, accidental injury should be considered.

OBJECTIVE A postoperative visual field defect resulting from damage to the occipital lobe during surgery is a unique complication of the occipital transtentorial approach. Though the association between patient position and this complication is well investigated, preventing the complication remains a challenge. To define the area of the occipital lobe in which retraction is least harmful, the surface anatomy of the brain, course of the optic radiations, and microsurgical anatomy of the occipital transtentorial approach were examined. METHODS Twelve formalin-fixed cadaveric adult heads were examined with the aid of a surgical microscope and 0° and 45° endoscopes. The optic radiations were examined by fiber dissection and MR tractography techniques. RESULTS The arterial and venous relationships of the lateral, medial, and inferior surfaces of the occipital lobe were defined anatomically. The full course of the optic radiations was displayed via both fiber dissection and MR tractography. Although the stems of the optic radiations as exposed by both techniques are similar, the terminations of the fibers are slightly different. The occipital transtentorial approach provides access for the removal of lesions involving the splenium, pineal gland, collicular plate, cerebellomesencephalic fissure, and anterosuperior part of the cerebellum. An angled endoscope can aid in exposing the superior medullary velum and superior cerebellar peduncles. CONCLUSIONS Anatomical findings suggest that retracting the inferior surface of the occipital lobe may avoid direct damage and perfusion deficiency around the calcarine cortex and optic radiations near their termination. An accurate understanding of the course of the optic radiations and vascular relationships around the occipital lobe and careful retraction of the inferior surface of the occipital lobe may reduce the incidence of postoperative visual field defect.

Objective: We aimed to identify the factors that can predict the risk of occipital lobe damage preoperatively when resecting tumors located at the tentorial or pineal regions with the occipital-transtentorial approach (Poppen approach)., Methods: In 27 consecutive patients who underwent tumor resection with the Poppen approach for tentorial or pineal region meningiomas, the following morphologic parameters were assessed on a preoperative magnetic resonance imaging: (1) tentorial angle, (2) tentorial length, and (3) the shortest distance from the confluence of the sinus to the tumor. These parameters, together with tumor size, texture, and resection extent, were correlated with occipital lobe damage by using the one-way analysis of variance, χ 2 , or Fisher's exact tests., Results: The mean value was 55.3° ± 5.6° (range, 45°-66°) for the tentorial angle, which was significantly associated with the occipital lobe damage grades (P = 0.008), but this was not the case for the tentorial length (P = 0.802) and the shortest distance from the confluence of the sinus to the tumor (P = 0.695). Interestingly, age was also strongly associated with occipital lobe damage risk (P = 0.020). The patients in the subgroup with no occipital damage (grade 4) were the youngest (aged 47.3 years), compared with other grades, with age of 58.0 years for grade 1, 54.3 years for grade 2, and 58.6 years for grade 3. These 2 parameters were also significant after multivariate analysis. No correlation was observed between either tumor nature or the extent of resection and damage grades., Conclusions: The risk of occipital lobe damage increases in the presence of a steep tentorial angle during the Poppen approach for tentorial or pineal area tumors. Awareness of such anatomic features preoperatively is important for minimizing operative complications., (Copyright © 2017. Published by Elsevier Inc.)

Brodmann areas 17, 18, and 19 in the human brain are visual cortices of the occipital lobe. Each area has its own retinotopic representations, particulary area 19, which has many small retinotopic areas representing half or all of the contralateral visual field, several functional areas, and nine cytoarchitectonic areas. Several fasciculi are known as occipital fiber connections, but their precise endpoints are not clear. Lesions in the visual cortices cause several visual disorders including visual field defect, visual hallucinations, metamorphopsia, and different kinds of visual agnosia.

Degeneration of neuron and axons following injury to cells with which they synapse is termed trans-synaptic degeneration. This phenomenon may be seen in postsynaptic neurons (anterograde) or in presynaptic neurons (retrograde). Retrograde trans-synaptic degeneration (RTSD) of the retinal ganglion cells and retinal nerve fiber layer following injury to the occipital lobe has been well documented histologically in animal studies, but its occurrence in the human retina was, for many years, felt to be limited to cases of neonatal injury during a critical period of neuronal development. Over the last decade, imaging techniques such as MRI and optical coherence tomography have allowed us to visualize and quantify RTSD and analyze its time course and relationship to degree of vision loss and age of cortical injury. A deeper understanding of RTSD in the human visual system may allow us to interfere with its occurrence, potentially allowing for greater recovery following visual cortex injury.

Although face detection likely played an essential adaptive role in our evolutionary past and in contemporary social interactions, there have been few rigorous studies investigating its neural correlates. MJH, a prosopagnosic with bilateral lesions to the ventral temporal-occipital cortices encompassing the posterior face areas (fusiform and occipital face areas), expresses no subjective difficulty in face detection, suggesting that these posterior face areas do not mediate face detection exclusively. Despite his normal contrast sensitivity and visual acuity in foveal vision, the present study nevertheless revealed significant face detection deficits in MJH. Compared with controls, MJH showed a lower tolerance to noise in the phase spectrum for faces (vs. cars), reflected in his higher detection threshold for faces. MJH's lesions in bilateral occipito-temporal cortices thus appear to have produced a deficit not only in face individuation, but also in face detection.

This study used magnetic resonance imaging to analyze causes and clinical courses of pediatric occipital lobe injury. Patients undergoing magnetic resonance imaging for suspected bilateral occipital lobe injury at our Neurodevelopmental Department between July 2007 and June 2011 were included. We evaluated magnetic resonance imaging characteristics, clinical courses, electroencephalogram monitoring, and Denver Development Screen Test scores. Twenty-one infants were examined. Of these, 10 had been born preterm. Thirteen patients demonstrated hypoglycemia. Perinatal period hypoglycemia comprised the most common cause (71.4%) of occipital brain injury. Visual abnormalities were evident in 18 patients. Seventeen (80.9%) patients manifested epilepsy. Infantile spasms were observed in 13 cases (76.5%). According to Denver Development Screen Test assessment, 17 patients demonstrated delayed motor development. Motor function and language improved in 10 patients after effective control of their seizures. Hypoglycemia constitutes the most common cause of occipital injury in infants. Visual impairment, startle episodes, infantile spasms, and motor developmental delay comprise the most common complications, whereas language function is usually spared., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Following damage to the human post-geniculate visual pathway retrograde trans-synaptic degeneration of the optic nerve fibres occurs. It has been known for some time from investigations carried out in primates that a decline in the number of retinal ganglion cells follows occipital lobectomy. However, this is not detectable in all species studied and whether this occurs in humans was controversial until recent studies that have shown that following lesions of the occipital lobe, the retinal nerve fibre layer thickness measured by optical coherence tomography is reduced and corresponding shrinkage of the optic tract can be demonstrated by magnetic resonance imaging. The time course of the degeneration in humans is, however, unknown. In the present study, we have used optical coherence tomography to demonstrate for the first time progressive thinning of the retinal nerve fibre layer following occipital lobe/optic radiation damage due to stroke. First, in a group of 38 patients the measurement was taken on a single occasion at a known time interval since the stroke, ranging from 6 days to 67 years. Here, a negative straight line relationship (linear regression r = 0.54, P < 0.001) was found between nerve fibre layer thickness and elapsed time since injury in log years, giving a rate of decline of 9.08 µm per log year after adjusting for age. This indicates a decelerating rate of loss that differs from the rate of decline found with chronological age in this same group, which shows a steady rate of thinning by 0.4 µm per year (P = 0.006) after adjusting for duration of the disease. In a second study serial measurements were taken following the acute event in a group of seven patients with homonymous hemianopia; here a negative straight line relationship was found between time and nerve fibre layer thickness in micrometres over a period of data collection beginning at a mean of 36.9 days post-stroke (range 5-112) and ending at a mean of 426.6 days post-stroke (range 170-917). Evidence from clinical observation (funduscopy) suggested that retrograde trans-synaptic degeneration occurred in humans only where the damage to the post-geniculate pathway occurred prenatally. The results reported herein add weight to the previous demonstration that this type of degeneration does indeed occur in the human visual system by showing that it can be monitored over time and hence may provide a model for trans-synaptic degeneration in the human central nervous system.

Background: The purpose of this study was to analyse the differences between patients with frontal (FEDH) or parieto-occipital (POEDH) epidural haematomas and evaluate possible statistically significant prognostic factors., Material and Methods: In this retrospective study of a group of 41 patients with a FEDH (17) or POEDH (24 individuals), the authors analysed the influence of gender, age, type of injury, clinical presentation, Glasgow coma scale (GCS) score on admission, radiological findings, and time interval from trauma to surgery on outcomes. A good recovery and moderate disability were considered a "good" or "favourable outcome", whereas severe disability, a vegetative state or death was a "poor outcome"., Results: In the POEDH subgroup, a higher GCS score on admission and a younger age were statistically significant prognostic factors for a better outcome (p=0.006, rs=0.702). In the subgroup of patients with FEDHs, the results were not significant. However, patients with FEDHs more frequently had "good outcomes" than members of the POEDH subgroup (88.2 vs. 70.9%). Children (≤ 18 years old) constituted a smaller portion of the POEDH subgroup (12.5%) than those in the FEDH subgroup (41.2%). The evaluation of time intervals between the accident and surgery (≤ 24 h vs. > 24 h) showed no significant influence on outcomes in any of the studied subgroups. However, patients undergoing surgery within 24 h of their injury had a less favourable GCS score on admission than those operated on more than 24 h after their injury. Subacute and chronic clinical courses predominated in patients with a FEDH (10/17 FEDH vs. 11/22 POEDH). Different accompanying intradural lesions occurred in 12 patients of the POEDH subgroup, but only in 2 of the FEDH subgroup (50 vs. 11.8%). However, the presence of such lesions did not significantly deteriorate surgical outcomes in either of the subgroups., (© Georg Thieme Verlag KG Stuttgart · New York.)

We present two cases (A.C. and W.J.) with navigation problems resulting from parieto-occipital right hemisphere damage. For both the cases, performance on the neuropsychological tests did not indicate specific impairments in spatial processing, despite severe subjective complaints of spatial disorientation. Various aspects of navigation were tested in a new virtual reality task, the Virtual Tübingen task. A double dissociation between spatial and temporal deficits was found; A.C. was impaired in route ordering, a temporal test, whereas W.J. was impaired in scene recognition and route continuation, which are spatial in nature. These findings offer important insights in the functional and neural architecture of navigation.

Background and Aim: The extrastriate cortex is a visual processing structure beyond the striate cortex. This region contains cells that differ in selectivity for different features of stimuli such as color, motion and stereopsis. We studied stereopsis and color vision in patients with right extrastriate cerebral lesions., Methods: Patients with right extrastriate cerebral lesions determined by MRI were recruited among consecutive inpatients. Patients with cognitive impairment (Mini Mental Status Examination score <24) were excluded. An ophthalmologist performed cortical visual testing: visual acuity, stereopsis, color vision and strabismus within 1 week after the insult., Results: Cortical visual testing was performed in 12 patients. Among the patients studied, 11 demonstrated abnormalities: reduced stereoacuity (8/12), color vision abnormalities (7/12). Seven patients showed complex cortical visual abnormalities. However, only 2 patients complained of subjective clinical symptoms. The MRI lesions in patients with disturbance of stereopsis were located in the dorsal occipitoparietal area and the ventral occipitotemporal area. Color vision abnormalities corresponded to lesions in the ventral occipitotemporal area., Conclusions: Patients with lesions in the right extrastriate cortex tend to have disturbance of stereopsis and color vision abnormalities, even in the absence of visual complaints., (Copyright 2008 S. Karger AG, Basel.)

We studied the relationships between magnetic resonance imaging (MRI) findings and neuropsychological sequelae in children after severe traumatic brain injury. Twenty-three children ages 7-13 years underwent MRI assessment of brain lesion topography and volume and neuropsychological evaluations, more than 1 year after sustaining severe traumatic brain injury. Most children had lesions to the corpus callosum and frontal lobes. Total lesion volume and extent of cerebral atrophy did not impact on the neuropsychological evaluation. Additional relationships were observed: left frontal lesions with lower semantic verbal fluency, right occipital lesions with lower visual recognition task scores, dyscalculia with cerebellar lesions, and cerebellar damage with lower cognitive performances and lower visual recognition memory. This study demonstrates the significance of the cerebellum's role in neuropsychological outcomes after traumatic brain injury and the importance of the lesion depth classification in predicting functional results.

Background: There are few published large series on civilian craniocerebral gunshot injuries in children. Traumatic intracranial aneurysms (TICAs) are rare and highly unstable lesions. They represent less than 1% of all aneurysms and can either rupture within minutes after formation or remain quiescent for several weeks or years, manifesting with delayed hemorrhage and neurologic deterioration., Case History: We report the case of a 10-year-old girl who was referred for coma after high-velocity craniocerebral gunshot wound and neurological deterioration 7 days after the initial injury. A massive right posterior occipital hematoma caused by the rupture of an unsuspected right posterior cerebral artery TICA was discovered. TICA was treated by coil embolization, with a good neurological recovery at 6-month follow-up., Discussion: We discuss the pathogenesis and the management of TICA in a child after civilian craniocerebral gunshot injuries., Conclusions: TICAs should be suspected in patients with civilian craniocerebral gunshot injuries, presenting with secondary neurological deterioration, to carry out emergent CT scan and angiographic exploration before contemplating definitive endovascular treatment. Endovascular management may be a prompt safe-to-use technique and a valuable option, especially when surgery is highly risky.

The process of visuo-spatial updating is crucial in guiding human behaviour. While the parietal cortex has long been considered a principal candidate for performing spatial transformations, the exact underlying mechanisms are still unclear. In this study, we investigated in a patient with a right occipito-parietal lesion the ability to update the visual space during vestibularly guided saccades. To quantify the possible deficits in visual and vestibular memory processes, we studied the subject's performance in two separate memory tasks, visual (VIS) and vestibular (VES). In the VIS task, a saccade was elicited from a central fixation point to the location of a visual memorized target and in the VEST task, the saccade was elicited after whole-body rotation to the starting position thus compensating for the rotation. Finally, in an updating task (UPD), the subject had to memorize the position of a visual target then after a whole-body rotation he had to produce a saccade to the remembered visual target location in space. Our main findings was a significant hypometria in the final eye position of both VEST and UPD saccades induced during rotation to the left (contralesional) hemispace as compared to saccades induced after right (ipsilesional) rotation. Moreover, these deficits in vestibularly guided saccades correlated with deficits in vestibulo-ocular time constant, reflecting disorders in the inertial vestibular integration path. We conclude that the occipito-parietal cortex in man can provide a first stage in visuo-spatial remapping by encoding inertial head position signals during gaze orientation.

A case of compound depressed fracture of occipital bone in 52-years old man caused by crane hook is presented. Bone fragments were depressed 40 millimetres causing blindeness and huge hemorrhage with symptoms of hemorrhagic shock. Laceration of left occipital lobe and penetration of superior sagittal sinus were treated during the operation. Primary elevation, debridement and primary bone replacement with additional covering of bone defect by bone cement were performed. Primary wound healing was achieved. Cortical blindeness subsided to the stage of contralateral homonymous hemianopia.

Occipital brain injury associated with neonatal hypoglycemia can result in long-term disability, epilepsy, and visual impairment. The etiology of this pattern of injury is unclear; however, transient hyperinsulinism may be an independent risk factor. Magnetic resonance brain imaging can delineate the extent of brain injury and guide follow-up.

A 47 year-old Thai man presented with acute bilateral blindness after suffering head trauma in a motorcycle accident. No neurological deficit was found. The visual acuity was light perception with poor light projection on both eyes. Other ocular examinations were normal except ecchymosis on both lower eyelids and mild subconjunctival hemorrhage on the left eye. Emergency computerized tomography showed normal appearance of optic nerves, optic canals and multiple contusional intracerebral hemorrhages at both occipital lobes. This case demonstrated a rare condition of permanent cortical blindness without other neurological deficits resulting from a head trauma.

We report a case-study of YE, a 54-year-old person who suffered multiple shell injuries that caused a right-parietal lesion and left hemianopia, almost 30 years ago. We conducted 4 experiments using a basic extinction paradigm in which YE had to report single stimuli presented on the left or right or two stimuli presented simultaneously in both visual fields. We show that extinction was selectively affected both by increasing the relative perceptual salience of the contralesional stimulus and by cueing attention to the contralesional side. The effects of perceptual salience and attentional cueing interacted, with cueing being more effective when the stimuli had relatively high perceptual salience. The data are consistent with attentional and perceptual factors interacting to determine the competition between left and right side stimuli that underlies extinction.

Damage to the occipital lobe of the brain results in hemianopia when unilateral, and cerebral blindness when bilateral. However, in some cases a degree of visual function persists in the blind visual field. This aim of this study was to describe this phenomenon of 'blindsight' in a cohort of children with brain-damage and to relate the clinical features to their visual evoked potentials. We performed a retrospective analysis of 541 case records of children referred to a tertiary vision-assessment clinic in the Royal Hospital for Sick Children, Glasgow, UK from 1992 to 2002. A total of 541 patients were analyzed (243 females, 298 males; age range 2 mo to 19 y 6 mo, mean 6 y 2 mo). In 19 children with profound visual impairment and four children with hemianopia (12 females, 11 males; age range 1 to 18 y, mean age 8 y 3 mo), evidence of perception of movement in the blind visual field was found and is described. Flash visual evoked potentials varied from no response to normal and was not correlated with visual behaviour. Recognition, detection, and use of this phenomenon in children is vital to their rehabilitation and interaction with their surroundings.

Background: Patients with prosopagnosia from occipitotemporal lesions have impaired perception of the configuration of facial features. This may be an example of impaired "within-object" spatial coding, which others propose to be distinct from "between-object" spatial coding., Objective: To determine whether the prosopagnosic deficit in perceiving spatial configuration was specific to within-face and not between-face spatial coding and whether the deficit was face-selective or extended to objects other than faces., Methods: Six prosopagnosic patients were tested using an oddity paradigm in which they detected which of three simultaneously seen stimuli was an altered target. In the "within-face" task, the target face had altered interocular distance or mouth position. In the "between-face" task, the target face was located farther away from the other two. In the "within-object" task, the stimulus was a two-dot pattern, and the target pattern had altered interdot distance., Results: Spatial judgments were impaired within faces for all six patients and within the two-dot pattern for five of six patients. However, all six had normal between-face spatial perception., Conclusions: Impaired perception of spatial relations in prosopagnosia is selective to the spatial structure within individual objects and spares the perception of spatial location of objects. It is not specific to faces. It reveals a process involved in analyzing object structure, consistent with the patients' deficits in recognizing facial identity, and illustrates a different type of "visuospatial" defect.

Traumatic brain damage can result in severe visual impairments including hemianopia. Lesions correlated with hemianopia can be located in any part of the retrochiasmatic optic pathway. However, traumatic lesions of the optic tract are relatively rare. We present a case with posttraumatic left homonymous hemianopia who had signal intensity change at the ipsilateral optic tract on MR imaging and ipsilateral occipital hypoperfusion on SPECT imaging.

Rapid resolution of acute subdural hematoma is rare. Delayed traumatic intracerebral hematomas following medical or surgical treatment of increased intracranial pressure have also been reported. Coexistence of a quickly resolving acute subdural hematoma and a delayed traumatic intracerebral hemorrhage has not been reported before. A 13-month-old boy was admitted to our emergency department after a car accident. On CT, a thin acute subdural hematoma on the right frontotemporal region and a small epidural hematoma on the left frontal region could be seen. On 24-hour follow-up CT, the right subdural hematoma was found to be less dense but larger than it had been before. At 36 h after hospitalization, CT showed that the right acute subdural hematoma had completely disappeared; however, a delayed traumatic intracerebral hematoma on the left occipital region was identified. We think that the mechanism involved in the development of a delayed intracerebral hematoma in our case was similar to the one causing delayed traumatic intracerebral hematoma after treatment for increased intracranial pressure.

Background: Biopsy of a dorsal mesencephalon lesion often leads to neuro-ophthalmological complications, namely dorsal mesencephalic syndrome, skew deviation, IV (th) palsy, or Horner's syndrome., History and Signs: A 26-year-old man underwent a biopsy of the quadrigeminal plate for a lesion which revealed to be neurosarcoidosis. Post-operative complications included a left homonymous hemianopia, a left III (rd) nucleus palsy, a bilateral IV (th) palsy and a bilateral internuclear ophthalmoplegia. Palpebral fissures were narrowed to 2 mm on both sides. In primary gaze there was 24 degrees of exotropia, 17 degrees of right hypertropia and 30 degrees of exyclorotation., Therapy and Outcome: After 24 months of stable evolution, three oculomotor surgical procedures were performed including: surgery on both horizontal muscles of the left eye; shortening of both superior oblique muscles; resection of the right lateral rectus muscle, and posterior fixation of an inferior rectus muscle. Bilateral brow suspension on the frontal muscle of both superior eyelids was then performed. Evolution was favorable with a binocular single field of vision measuring 17 degrees horizontally and 20 degrees vertically centered on the primary gaze. Palpebral fissures measured 7 to 8 mm in primary gaze., Conclusions: The neuro-ophthalmological sequelae which followed the biopsy of a neurosarcoidosis lesion of the quadrigeminal plate were so severe that this patient was completely handicapped. A four-step surgery correcting the horizontal, torsional, vertical components, then the bilateral ptosis allowed the patient to recover both a satisfying function and esthetical aspect.

We know that cats with bilateral lesions of occipital visual cortical areas 17, 18 and 19 sustained during the first postnatal week exhibit a modest level of sparing of the ability to re-orient head and eyes to new stimuli relative to cats that incurred equivalent lesions in adulthood. We now report that cats with equivalent unilateral lesions sustained during the first postnatal week (P1-4), or at the end of the first postnatal month (P27-30), orient to stimuli presented in the contralesional field as proficiently as to stimuli introduced into the ipsilesional field. Moreover, levels of proficiency are indistinguishable from those exhibited by intact cats. Thus, the sparing is greater following unilateral lesions than following bilateral lesions, and the level of sparing approaches completeness. The difference between the bilateral and unilateral lesion results suggests types of pathway reorganizations that may emerge as a result of unilateral occipital lesions. We postulate that the greater sparing is based on modifications in both excitatory and inhibitory circuitry linked to the intact hemisphere, and we provide a framework for future investigations that should be relevant to the comprehension of the repercussions of early unilateral and bilateral lesions sustained by monkeys and humans, which also show more robust residual vision following early relative to later damage of occipital cortex.

Introduction and Objective: Cognitive deficits following lesions in parieto occipital areas tend to cause, among others, visuospatial and visuoperceptive alterations. The aim of this article is to examine the influence of others possible deficit over its rehabilitation., Development: We discuss several patients who present visuospatial impairment after different brain injuries, not only those affecting the areas typically involved in these deficits, such as parieto occipital cortex. Rehabilitation was conducted on an individual basis in the brain injury unit of Beata Maria Ana hospital. Neuropsychological evaluation showed some difficulties not previously described together with these deficits, related to attention, working memory and executive functions, as well as topographic disorientation, lack of visuospatial coordination, distances perception disorders and difficulty to mentally rotate objects. The rehabilitation was AIMed not only at restoration but also compensation of visuospatial deficits, successfully achieved after treatment: patients were capable of returning to their daily activities, including their jobs., Conclusion: In patients with visuospatial deficits, a compressive neuropsychological evaluation seem to be essential to define the influence of the other cognitive domains over the rehabilitation of visuospatial problems. In particular, the reinforcement of processes related to attention control and executive functions could very important, give their contribution to the learning of compensatory strategies and assuming that those functions pay key role in the organization and supervision demanded for perceptual skills.

Objective: The presented case study describes the beneficial results of the neuropsychological rehabilitation of a gunshot victim, even with late initialization of the therapy--over 1 year after head trauma., Design: A case study of DE, a victim with bilateral damage of the parietal-occipital regions of the brain due to a gunshot., Methods: Neuropsychological rehabilitation, first preceded by an initial neuropsychological examination (standard psychological tests: WAIS-R, RAVLT, Rey's CFT, BVRT and clinical experiments tailored to DE's condition), was initiated 1 year after trauma. The rehabilitation programme consisted of computer-based tasks, paper-and-pencil exercises, and occupational therapy. The patient's progress was assessed as improvement in performance in standardized tests and computer-based tasks., Results: DE was diagnosed with complex cognitive deficits syndrome, including visual associative agnosia, apraxia, visuospatial and constructive disorders and linguistic defects. After 1 year of rehabilitation the patient's functioning significantly improved as measured by psychological tests and computer-based tasks (p<0.05) as well as the evaluation of the patient's quality of life., Conclusions: The case study demonstrates beneficial effects of neurorehabilitation even initialized at the so-called 'late stage' after a brain injury.

In adults and children, head trauma can have long-term neuropathological and functional consequences. The thalamus is a major site of remote neurodegeneration after cortical damage in adult humans and experimental animals, but less is known about thalamic responses to cortical injury in the immature brain. This study introduces an in vivo model of axotomy/target deprivation-induced neuronal apoptosis in the dorsal lateral geniculate nucleus of the thalamus produced by unilateral ablation of the occipital cortex in the immature mouse. We specifically examined whether occipital cortex ablation in the immature brain causes apoptotic death of projection neurons in the dorsal lateral geniculate nucleus. After unilateral occipital cortex aspiration, 10-day-old C57BL/6 mice were recovered for up to 28 days. Fluorogold-prelabeled thalamocortical projection neurons were apoptotic at 36-48 h after ablation. The structural progression of apoptosis in the immature lateral geniculate nucleus reveals typical chromatolytic morphology by 18-24 h, followed by cytoplasmic shrinkage and chromatin condensation characteristic of end-stage apoptosis after 36-48 h. Electron microscopy confirmed the presence of apoptosis. This study shows internucleosomal DNA fragmentation and expression of cleaved caspase-3 occurs rapidly, being noted first at 18 h, well before the peak of apoptotic cell death occurring at 36 h after cortical damage in the immature brain. From these data we suggest that axotomy/target deprivation-induced cell death in the immature brain may: (1) differ from that previously reported in adult mice with respect to the time required for progression to cell death; (2) be mediated by caspase-3 activation.

The mechanisms of injury-induced apoptosis of neurons within the CNS are not understood. We used a model of cortical injury in rat and mouse to induce retrograde neuronal apoptosis in thalamus. In this animal model, unilateral ablation of the occipital cortex causes unequivocal apoptosis of corticopetal projection neurons in the dorsal lateral geniculate nucleus (LGN) by 7 days postlesion. We tested the hypothesis that p53 and Bax regulate this retrograde neuronal apoptosis. We found, by using immunocytochemistry, that p53 accumulates in nuclei of neurons destined to undergo apoptosis. By immunoblotting, p53 levels increase ( approximately 150% of control) in nuclear-enriched fractions of the ipsilateral LGN by 5 days after occipital cortex ablation. p53 is functionally activated in nuclear fractions of the ipsilateral LGN at 5 days postlesion, as shown by DNA binding assay (approximately fourfold increase) and by immunodetection of phosphorylated p53. The levels of procaspase-3 increase at 4 days postlesion, and caspase-3 is activated prominently at 5 days postlesion. To identify whether neuronal apoptosis in the adult brain is dependent on p53 and Bax, cortical ablations were done on p53 and bax null mice. Neuronal apoptosis in the dorsal LGN is significantly attenuated (approximately 34%) in p53(-/-) mice. In lesioned p53(+/+) mice, Bax immunostaining is enhanced in the ipsilateral dorsal LGN and Bax immunoreactivity accumulates at perinuclear locations in dorsal LGN neurons. The enhancement and redistribution of Bax immunostaining is attenuated in lesioned p53(-/-) mice. Neuronal apoptosis in the dorsal LGN is blocked completely in bax(-/-) mice. We conclude that neuronal apoptosis in the adult thalamus after cortical injury requires Bax and is modulated by p53., (Copyright 2001 Wiley-Liss, Inc.)

A variety of adult, non-neural tissues respond to injury by increasing expression of the gene which encodes for insulin-like growth factor-1 (IGF-1). This response is thought to be a key component in the regenerative capacity of these tissues. In contrast, the central nervous system (CNS) has relatively little regenerative capacity following injury. Interestingly, compared to many non-neuronal tissues, little IGF-1 mRNA can be detected in the adult CNS, raising the possibility that its lack of regenerative capacity is related its relative lack of IGF-1 expression. However, in the 2-week-old adolescent CNS IGF-1 mRNA can be detected in numerous brain regions. Therefore, the purpose of this study was to determine the responsiveness of the IGF-1 gene to injury in adolescent CNS tissue, a period in which expression of this gene is relatively abundant. Expression of IGF-1 mRNA was measured by means of a sensitive solution hybridization/RNase protection assay in the parieto-occipital lobes of 2-week-old and adult mice following penetrating injury. Levels of IGF-1 transcript in the injured brains were significantly increased above those of controls in both 2-week-old and adult brains 3-day post injury and remained elevated for 1 week after injury. These observations demonstrate that the adult CNS, like other tissues, can respond to injury by increasing expression of IGF-1 mRNA., (Copyright 1998 Elsevier Science B.V. All rights reserved.)

We have examined the degree of precision in the topographic arrangement of the tectal projection developed by homotopic transplants of embryonic occipital cortex and tried to determine whether the development of the corticotectal projection is exclusively dependent on environmental cues or is also controlled by intrinsic factors. Transplants of embryonic (E16) occipital cortex were grafted into various areas of the occipital cortex (Oc1 or Oc2) of newborn rats and the organization of the tectal projection arising from the transplants was subsequently examined by injecting different neurotracers into the transplants. Our results indicate that in most cases the laminar and tangential distributions of the tectal projections from the transplants were abnormal. Indeed, whatever the location of the transplant in the host occipital cortex and whatever the placement of the injection into the transplant, a hybrid distribution of the tectal labeling was found, reminiscent of the pattern observed following tracer deposits in both Oc1 and Oc2 in intact animals. Since the grafts were composed of cells of both Oc1 and Oc2 embryonic origin, it is likely that the hybrid pattern of efferents reflects the heterogeneity of the embryonic origin of the cells composing the graft. These findings provide evidence that the development of the topographic distribution of neocortical efferents is not only dependent on factors extrinsic to the cortex and further indicate that even within one single cortical region, the occipital cortex, different areas (Oc1 vs Oc2) are not totally interchangeable. These findings might have important implications in transplantation experiments aiming at the reconstruction of damaged neocortical circuitry where a precise "point-to-point" reconstruction of the circuitry is expected.

The present investigation explored the extent to which extrastriate cortex is necessary for various aspects of motion processing and whether the processing of first-order (Fourier) and second-order (non-Fourier) motion involves the same extrastriate cortical regions. Orientation, direction, and speed discrimination thresholds were measured in 21 patients with unilateral damage to the lateral occipital, temporal, or posterior parietal cortex. Their results were compared with those of 14 age-matched control subjects. The stimuli were static random-dot noise patterns, the luminance of which (first-order) or contrast (second-order) was modulated by a drifting sinusoid. Each image was presented at an eccentricity of 5.6 deg in one of the four visual quadrants. The contrasts required to identify orientation and direction were measured in a forced-choice paradigm for three speeds (1.5, 3, and 6 deg/sec). Speed discrimination performance was measured for stimuli presented simultaneously in two of the four quadrants. The results indicate the following: (1) orientation thresholds were increased only slightly in the patients; (2) direction thresholds were modestly elevated, and this effect was more pronounced for second-order stimuli than for first-order stimuli; (3) speed discrimination thresholds were elevated significantly in the patients with lesions in the region bordering superior-temporal and lateral-occipital cortex; and (4) speed discrimination thresholds for first-order stimuli were more elevated than those for second-order stimuli. The results suggest that there is substantial overlap in the cortical areas involved in first- and second-order speed discrimination.

An 8-year-old boy, who fell downstairs and struck his head, and a 62-year-old female, who hit her head in the automobile accident, presented with unusual traumatic acute subdural hematoma localized on the superior surface of the tentorium cerebelli. Magnetic resonance imaging was useful for determination of the anatomical location of the hematoma, and confirmation of absence of significant parenchymal contusion. Injury of the variant bridging vein possibly caused subdural hematoma over the tentorium.

We tested the hypothesis that partial forms of retrograde amnesia were associated with highly asymmetric lesions to the inferior and anterior-medial temporal lobe. Postencephalitic subjects EK and DR were both impaired on standardized retrograde memory tests, but showed strikingly different profiles in cognitive tasks of name stem completion, name:face matching, temporal ordering, forced choice recognition, and occupational judgments of famous names and faces from the past 3 decades. EK sustained left inferior and anterior-medial temporal lobe lesion with a small right temporal polar lesion, and showed near-complete loss of retrieval, knowledge, and familiarity associated with famous names but minimal deficiencies with famous faces. DR sustained right inferior and anterior-medial temporal lobe lesion and showed a milder retrograde loss limited to utilizing famous face prompts in name stem completion, name:face matching, occupational judgments, and forced choice recognition. These impairments were also different from the memory retrieval deficit, but intact recognition shown by a case of ruptured anterior communicating artery aneurysm with presumed basal forebrain damage. We hypothesize that EK's extensive loss of famous name knowledge was related to left inferior temporal lobe damage, particularly in the lateral and medial occipitotemporal gyri. This region in the left temporal lobe may serve as a critical processing area for retrograde memory that permits activation of established semantic, temporal, and visual (i.e., facial) associations biographically dependent on the category of proper names. On the basis of connectional anatomy patterns in the nonhuman primate, this region receives extensive hippocampal output and is interconnected with the temporal polar region and cortical association areas, which have been implicated in retrieval and storage aspects of retrograde memory. In the right hemisphere, the occipitotemporal gyri may serve an important role in famous face processing as part of a bilateral neural network.

The morphological consequences of delayed posttraumatic brain hyperthermia (39 degrees C) after fluid percussion brain injury were assessed in rats. Sprague-Dawley rats anesthetized with 4% halothane and maintained on a 70:30 mixture of nitrous oxide:oxygen and 0.5% halothane underwent moderate (1.5-2.0 atm) traumatic brain injury with the injury screw positioned parasagittally over the right parieto-occipital cortex. At 24 hours after traumatic brain injury, the rats were reanesthetized and randomized into two groups in which either a 3-hour period of brain normothermia (36.5 degrees C, n = 18) or hyperthermia (39 degrees C, n = 18) was maintained. Sham-operated controls (n = 10) underwent all surgical and temperature-monitoring procedures. After the 3-hour monitoring period, the rats were allowed to survive for 3 days for light microscopic analysis or were injected with the protein tracer horseradish peroxidase and were perfusion-fixed 15 minutes later for light and electron microscopic analysis. At 4 days after traumatic brain injury, delayed posttraumatic hyperthermia (n = 12) significantly increased mortality (47%) and contusion volume (1.7 +/- 0.69 mm3, mean +/- standard error of the mean), compared to normothermia (n = 12) (18% mortality and 0.13 +/- 0.21 mm3 contusion volume) (P < 0.01, analysis of variance). At 15 minutes after the 3-hour hyperthermic period, the area of hemorrhage and horseradish peroxidase extravasation overlying the lateral external capsule was significantly increased (2.52 +/- 0.71 mm2, mean +/- standard error of the mean, versus 0.43 +/- 0.16 mm2) (P < 0.01), compared to normothermic rats. Examination of toluidine blue-stained plastic sections demonstrated a higher frequency of abnormally swollen myelinated axons per high microscopic field with hyperthermia. For example, numbers of swollen axons within the sixth layer of the right somatosensory cortex, corpus callosum, and internal capsule were 7.3 +/- 1.3, 4.2 +/- 1.4, and 3.0 +/- 1.2 axons (mean +/- standard error of the mean) with normothermia, respectively, compared with 24.7 +/- 12.1, 33.1 +/- 4.2, and 27.3 +/- 3.1 axons with hyperthermia, respectively (P < 0.01). An ultrastructural examination of the swollen axons demonstrated a severely thinned myelin sheath containing axoplasm devoid of cytoskeletal components. These experimental results indicate that posttraumatic brain hyperthermia might increase morbidity and mortality in patients with head injury by aggravating axonal and microvascular damage.

Seventeen patients with posterior fossa extradural haematoma are presented. While 7 patients had acute course, 6 had subacute and 4 had chronic course. All patients had evidence of occipital injury. Two patients did not have any fracture in the occipital bone. Concomitant lesions included cerebellar contusion in 3 cases, cerebral contusion in 4 patients, supratentorial extradural haematoma in 2 and hydrocephalus in 2 patients. All but one patient were treated surgically. None of the supratentorial lesions were operated upon. All patients with subacute and chronic course had good outcome while 43% with acute course succumbed to death. Besides the initial clinical status the co-existing lesions signifying the increased severity of injury have influenced the mortality and quality of outcome. In presence of occipital fracture a careful observation and timely intervention are warranted.