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Unusual Spontaneous and Training Induced Visual Field Recovery in A J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.70.2.236 on 1 February 2001. Downloaded from 236 J Neurol Neurosurg Psychiatry 2001;70:236–239 SHORT REPORT Unusual spontaneous and training induced visual field recovery in a patient with a gunshot lesion D A Poggel, E Kasten, E M Müller-Oehring, B A Sabel, S A Brandt Abstract field size could not be ruled out (for example, Over a period of more than 3 years, variability of perimetric measurements, change changes in visual and neuropsychological of detection strategies, or compensatory eccen- functions were examined in a patient with tric fixation) (see also Balliet et al3 for a review). a visual field defect caused by a cerebral However, more recent, methodologically well gunshot lesion. Initially, the patient had controlled studies provided evidence for train- been completely blind, but after 6 months ing induced recovery of visual functions.45 of spontaneous recovery, he showed a Here, we report on a patient with a traumati- homonymous bilateral lower quadran- cally induced visual field defect showing tanopia and impairment of higher visual significant spontaneous recovery and consider- functions. Unexpectedly, recovery still able further progress during visual restitution continued after the first 6 months. This training. For the first time we could show in process was documented in detail by detail that spontaneous as well as training visual field examinations using high reso- induced improvement take place in the area of lution perimetry. When visual field size residual vision and that both processes seem to had stabilised almost 16 months after the be based on a common mechanism—that is, lesion, further improvement could be the modulation of perceptual thresholds in achieved by visual restitution training. partially defective areas. The duration and extent of spontaneous recovery were unusual. In spontaneous as Case report well as in training induced recovery, A 29 year old man with no history of progress was mainly seen in partially neurological disease was attacked and shot in defective areas (areas of residual vision) the back of his head. When regaining con- along the visual field border. Thus, it is sciousness in the hospital, he complained of a speculated that modulation of perceptual complete loss of vision. Initially he also had http://jnnp.bmj.com/ thresholds in transition zones of visual anosmia, reduced vigilance, and a mild left field defects contributes to spontaneous sided hemiparesis. Reduction of vigilance and and training induced recovery. hemiparesis recovered completely within days. (J Neurol Neurosurg Psychiatry 2001;70:236–239) After 1 week, vision had recovered in the right upper quadrant, and central vision was suY- Keywords: visual field; hemianopia; recovery of function Institute of Medical cient to perform a neuropsychological exam- Psychology, ination which disclosed a slowing of reaction Otto-von-Guericke times as well as an impairment of short term on September 29, 2021 by guest. Protected copyright. University, Leipziger The human brain possesses a remarkable abil- memory and visuospatial functions. Verbal Strasse 44, 39120 ity to regain functions after lesions of various intelligence was normal. Magdeburg, Germany aetiologies. However, recovery from visual field Six months after the incident, we examined D A Poggel defects in patients with brain injury has long E Kasten the patient for the first time in our department. E M Müller-Oehring been considered impossible due to the highly General and cardiovascular examination B A Sabel specific structure of the visual system. Mean- yielded normal results. Higher cortical func- while, it is generally accepted that spontaneous tions and cranial nerves were normal except for Department of improvement can occur in patients with visual a bilateral lower quadrantanopia and hypos- Neurology, Charité, field loss, but there is still a controversial mia. Best corrected visual acuity was 100%. Humboldt University, discussion on the possibility of increasing Schumannstrasse Muscle tone, muscle strength, and reflexes 20–21, visual field size by systematic training. Zihl and were normal and symmetric. There was 1 10117 Berlin, Germany von Cramon tried to enlarge the visual field of hypaesthesia in a region at the back of the head S A Brandt 55 patients with postgeniculate lesions using a where the bullet had entered, otherwise sensa- forced choice saccadic technique to detect light tion was normal. In a detailed neuropsycho- Correspondence to: stimuli. In most patients, visual field enlarge- Dr B A Sabel@ logical examination, his performance was nor- medizin.uni-magdeburg.de ment did not exceed 5°, but there were mal, except in visuospatial tasks and in tests individual cases with remarkable recovery. involving a considerable amount of visual Received 13 March 2000 and Nevertheless, their findings were regarded as scanning (see below). Subjectively, the patient in revised form 2 29 September 2000 artefacts by Balliet et al. because alternative had diYculties in estimating direction and Accepted 11 October 2000 explanations for the increase of intact visual speed of moving objects. This caused problems www.jnnp.com J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.70.2.236 on 1 February 2001. Downloaded from Unusual spontaneous and training induced visual field recovery in a gunshot lesion 237 A1 3 19 85 163 10° 20° 30° B28 50 85 0° 0° 0° –10° –10° –10° –20° –20° –20° –30° –30° –30° –20° –10° 0° 10° 20° –20° –10° 0° 10° 20° –20° –10° 0° 10° 20° C 99 120 176 0° 0° 0° –10° –10° –10° –20° –20° –20° –30° –30° –30° –20° –10° 0° 10° 20° –20° –10° 0° 10° 20° –20° –10° 0° 10° 20° Figure 1 Spontaneous and training induced recovery of visual field. (A) Perimetric measurements (grey=blind, white=intact); weeks 1, 3, 19, 85 (spontaneous recovery), and 163 (training induced recovery) after lesion. (B) Measurements of lower visual field with computer based high resolution perimetry at weeks 28, 50, and 85. (C) Results from the beginning of the 1st training unit (week 99), the end of the 3rd training unit (week 120), and the end of the 8th training-unit (week 176); five subsequent training sessions are superimposed in each picture; grey areas correspond to partially defective regions of visual field. riding a bicycle, pouring liquids into a glass, background=26 cd/m2) were presented in ran- and walking through crowds of people. dom order at 474 positions in a grid of 25×19 Axial CT images (2 mm slice thickness) and stimulus locations. The subject was instructed coronal reconstructions showed that the bullet to keep his eyes on the fixation point through- had entered the left occipital lobe (about 5 cm out the test and to press the space bar on the http://jnnp.bmj.com/ cranial and 3 cm lateral to the inion) and computer keyboard on detection of a stimulus followed a trajectory through the interhemi- or of a fixation control (an isoluminant change spheric fissure into the right temporal lobe, of the fixation point’s colour). Additionally, eye where the bullet is still located. A hypodense position was controlled by the experimenter area involving the upper part of the cuneus and noting the subject’s fixation behaviour in a the caudal part of the precuneus bilaterally mirror. Interstimulus intervals were ran- could be identified. The lesion extended bilat- domised to prevent guessing behaviour. Total erally to the ventral part of the upper calcarine duration of the visual field test was about 20 on September 29, 2021 by guest. Protected copyright. bank, but spared striate cortex in the lower cal- minutes. The number of hits, misses, and false carine bank and the occipital poles. In the right positives as well as reaction times were hemisphere the hypodense area extended into registered by the program. Positions of cor- the posterior part of the medial temporal gyrus. rectly detected stimuli and misses were plotted as white and black squares in the stimulus grid, Methods respectively. A variation in this perimetric pro- Visual field recovery was found with diVerent cedure allowed for the testing of colour methods of quantitative perimetry (Allergan discrimination and form recognition. Humphrey 60°, Octopus 90°, Tübinger Auto- For visual field enlargement, we applied mated Perimeter 30° and 90°; see fig 1; see also computer based visual restitution training.47 Lachenmeyer and Vivell6 for description). Here, luminous stimuli were presented at ran- Additionally, we used a high resolution com- dom locations in a previously defined training puter based perimetric test78for more detailed area on a dark computer screen, each increas- examination of the central visual field. Testing ing in brightness from dark grey (30 cd/m2)to was done in a darkened room (background bright white (96 cd/m2) over a period of 2000 luminance=1.5 Lx) in front of a computer ms. Stimulus size, fixation control, mode of screen covering 54.8° horizontally and 42.3° response, and viewing distance were the same vertically. White light stimuli (luminance=96 as in the visual field test. Training was cd/m2; size=0.76°; presentation time=150 ms, performed at home for 1 hour daily. Treatment www.jnnp.com J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.70.2.236 on 1 February 2001. Downloaded from 238 Poggel, Kasten, Müller-Oehring, et al Start of high resolution Start of visual parallel, colour perception and form recogni- perimetric measurements restitution training tion recovered in the transition zone, and he 100 350 subjectively perceived an improvement of 90 visual orientation and spatial perception. 300 After visual field size had remained constant 80 for more than 7 months (week 51 to 94), visual 70 250 restitution training was started. The patient showed a remarkable but 60 200 variable further increase of visual field size over 50 the next 80 weeks of training (fig 1).
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