What''s new in surgery of flexor tendons?]

BACKGROUND: Visual acuity and vision related quality of life outcomes in cataract surgery were evaluated in a population based survey in two geographic zones in Nepal. METHODS: Case finding was based on random sampling using a stratified cluster design with door to door enumeration of people aged > or = 45 years followed by eye examinations at village sites. All aphakics/pseudophakics, those with visual acuity less than 6/60 in either eye, and a sample of those with normal visual acuity were administered visual functioning (VF) and quality of life (QOL) questionnaires. RESULTS: 15% of the 159 cataract operated cases had presenting visual acuity > or = 6/18 in both eyes, 38% with best corrected visual acuity. 21% were still blind with presenting visual acuity < 6/60 in both eyes, 7% with best correction. On a 0-100 scale, mean VF and QOL scores were 87.2 and 93.9 respectively in normally sighted unoperated individuals, dropping to 15.6 and 29.5 for those severely blind (< 3/60). Among the cataract operated, mean VF and QOL scores were 47.5 and 55.4, respectively. VF and QOL scores correlated with vision status at statistically significant levels (p < 0.0001). CONCLUSION: Cataract surgery outcomes, whether measured by traditional visual acuity or by patient reported VF/QOL, are at levels many would consider unacceptably low. It is apparent that in the quest to reduce cataract blindness much more attention must be given to improving surgery outcomes.     

Journeying beyond classical somatosensory cortex.

Visual cortical areas are involved in a variety of somatosensory tasks in the sighted, including tactile perception of two-dimensional patterns and motion, and haptic perception of three-dimensional objects. It is still unresolved whether visual imagery or modality-independent representations can better explain such cross-modal recruitment. However, these explanations are not necessarily in conflict with each other and might both be true, if imagery processes can access modality-independent representations. Greater visual cortical engagement in blind compared to sighted people is commonplace during language tasks, and also seems to occur during processing of tactile spatial information. Such engagement is even greater in the congenitally blind compared to the late blind, indicative of enhanced cross-modal plasticity during early development. At the other extreme, short-term visual deprivation of the normally sighted also leads to cross-modal plasticity. Altogether, the boundaries between sensory modalities appear to be flexible rather than immutable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imagery limitations in totally congenitally blind subjects.

Research on totally blind subjects performing tasks that involve visual imagery has often shown that they do not behave differently from matched sighted subjects, even when their blindness is congenital. If visual imagery is based on visual perception, such tasks may not require visual imagery. In the present article visual images are considered as representations maintaining some properties of visible objects and constructed on the basis of information from various sources. Owing to the absence of visual experience, the limitations of such representations are explored in a series of experiments requiring memorization of single nouns, pairs of nouns, or triplets of nouns associated with a cue noun. Recall by blind subjects was impaired when multiple interactive images (with noun pairs and triplets) are formed. The poorer recall of blind subjects reflected also loss of order information. Recall was better for both groups with locative noun cues and high-imagery targets. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual experience, visual field size, and the development of nonvisual sensitivity to the spatial structure of outdoor neighborhoods explored by walking.

When places are explored without vision, observers go from temporally sequenced, circuitous inputs available along walks to knowledge of spatial structure (i.e., straight-line distances and directions characterizing the simultaneous arrangement of the objects passed along the way). Studies show that a life history of vision helps develop nonvisual sensitivity, but they are unspecific on the formative experiences or the underlying processes. This study compared judgments of straight-line distances and directions among landmarks in a familiar area of town by partially sighted persons who varied in types and ages of visual impairment. Those with early childhood loss of broad-field vision and those blind from birth performed significantly worse than those with early or late acuity loss and those with late field loss. Broad-field visual experience facilitates perceptual development by providing a basis for proprioceptive and efferent information from locomotion against distances and directions relative to the surrounding environment. Differences in the perception of walking, in turn, cause the observed differences in sensitivity to spatial structure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Contribution of L-arginine-derived nitric oxide to the structural integrity of coronary artery and cardiac interstitium, and to the regulation of sympathetic nerve activity: assessment using a rat model produced by chronic nitric oxide inhibition

In this comparative study concerning characteristics of independent walking by visually impaired persons, we used a motion analyser system to perform gait analysis of 15 late blind (age 36-54, mean 44.3 years), 15 congenitally blind (age 39-48, mean 43.8 years) and 15 sighted persons (age 40-50, mean 44.4 years) while walking a 10-m walkway. All subjects were male. Compared to the sighted, late blind and congenitally blind persons had a significantly slower walking speed, shorter stride length and longer time in the stance phase of gait. However, the relationships between gait parameters in the late and congenitally blind groups were maintained, as in the sighted group. In addition, the gait of the late blind showed a tendency to approximate the gait patterns of the congenitally blind as the duration of visual loss progressed. Based on these results we concluded that the gait of visually impaired persons, through its active use of non-visual sensory input, represents an attempt to adapt to various environmental conditions in order to maintain a more stable posture and to effect safe walking.     

Telescopic lenses and driving

In some states, persons with significantly reduced visual acuity are being licensed to drive while wearing telescopic spectacle lenses (TSL). In order to evaluate possible visual field limitations present with these devices, the peripheral visual fields of a group of normally sighted subjects were measured while they wore TSL. Severely restricted central fields and sizeable ring scotomas were present with all units tested. These result indicate that driving with TSL should be discouraged.     

Causes of low vision and blindness in south western Saudi Arabia. A hospital-based study

The authors studied 1,681 consecutive patients who attended their ophthalmic outpatient clinics over a period of 12 months to determine the patients' visual acuity status and the causes of any visual loss. Using the World Health Organization criteria for definition of visual acuity status, 1004 (59.7%) patients had normal vision. Four hundred and thirty-one (25.6%) patients had low vision or visual impairment and 246 (14.6%) patients were blind. Twenty-eight (1.9%) patients had no light perception in both eyes. Cataract, both in isolation and co-existing with other ocular pathology, was the major cause of both low vision and blindness (58.5% and 81.7%, respectively). A concerted attack on cataract alone will markedly reduce blindness and low vision in this region.     

Vitrectomy for traction macular detachment in diabetic retinopathy

BACKGROUND: A small number of eyes with proliferative diabetic retinopathy develop massive central fibrovascular membranes characterized by vitreoretinal tractions along the arcades and optic disk and retinal traction lines extending through the macula. The aim of our study was first to present the results of vitrectomy for removal of these central membranes and second to determine the correlation between preoperative parameters and postoperative visual outcome. SUBJECTS AND METHODS: We treated 28 eyes with severe central fibrovascular diabetic membranes by a modified bi-manual en bloc excision technique during vitrectomy. Preoperative examination included general status, visual acuity, slit-lamp investigation, binocular funduscopy, ultrasound investigation and visual evoked potentials (VEP). Further, we analyzed intraoperative complications and postoperative anatomic and functional outcomes. RESULTS: The retinas of 27 eyes with central traction retinal detachments were reattached by surgery. With a minimum of 6 months' follow-up, the macula remained attached in 24 eyes, while the retinas were completely attached in 22 eyes. Preoperative visual acuity was defective light perception to 0.1; an increase in visual acuity to maximal 0.1 was seen in 50% of the patients postoperatively. Preoperative visual acuity of light perception was associated with no functional improvement. Preoperative ultrasound investigation gave information about the real anatomic situation of the retina, especially if funduscopy was not possible. The other preoperative parameters could not predict correctly the functional outcome of vitrectomy in diabetics with severe central fibrovascular membranes because of the damage of the optic nerve and the retina. CONCLUSIONS: The high rate of anatomical reattachment after vitrectomy in diabetic eyes with severe central fibrovascular membranes is associated with a slight improvement of function; only preoperative visual acuity of hand motions or better was associated with an improvement of function.     

Cell adhesion molecules in vasculitis

Daytime sleepiness is a common complaint in blind subjects. Abnormally timed melatonin has been invoked as a possible cause of both daytime sleepiness and nighttime awakening. In free-running blind individuals, there is an opportunity to assess the relationship between endogenous melatonin rhythms and subjective sleepiness and naps. The aim of this study was to characterize melatonin rhythms and simultaneously to evaluate subjective napping. A total of 15 subjects with no conscious light perception (NPL) were studied for 1 month. Prior to the study, sleep disorders were assessed using the Pittsburgh Sleep Quality Index. Cosinor and regression analysis revealed that 9 of the 15 NPL subjects had free-running 6-sulphatoxymelatonin (aMT6s) rhythms (period [tau] range = 24.34 to 24.79 h), 3 were entrained with an abnormal phase, and 3 were normally entrained. Most of the subjects (13 of 15) had daytime naps; the 2 individuals who did not made conscious efforts not to do so. Subjects with abnormal aMT6s rhythms had more naps of a longer duration than did those with normal rhythms. Free-running nap rhythms occurred only in subjects with free-running aMT6s rhythms. The 2 abnormally entrained subjects who napped did so at times that coincided with high levels of aMT6s (mean aMT6s acrophase [phi] +/- SD = 14.30 +/- 1.08 h, 20.30 +/- 0.62 h; mean nap time +/- SD = 14.01 +/- 3.60 h, 18.23 +/- 3.20 h, respectively). Regardless of aMT6s rhythm abnormality, significantly more naps occurred with a 4-h period before and after the estimated aMT6s acrophase. In 4 free-running subjects, aMT6s acrophase (phi) passed through an entire 24-h period. When aMT6s was in a normal phase position (24:00 to 06:00 h), night-sleep duration tended to increase with a significant reduction in the number and duration of naps. Sleep onset and offset times tended to advance and delay as the aMT6s rhythms advanced and delayed. Our results show a striking relationship between the timing of daytime production of melatonin and the timing of daytime naps. This suggests that abnormally timed endogenous melatonin may induce sleepiness in blind subjects.     

The role of vision in the Corsi Block-Tapping task: Evidence from blind and sighted people.

Objective: This study aims at adapting the Corsi Block-Tapping task to measure serial-spatial memory in blind people and at clarifying the role of visual experience in the task. Method: Congenitally blind, adventitiously blind, and blindfolded sighted people were compared on a version of the Corsi board that allowed the haptic perception of block positions (Haptic-Corsi). Participants placed their fingers on the blocks that the experimenter moved upward according to sequences of increasing length. Afterward, participants reproduced the sequences in forward/backward order. Results: The results showed a significant interaction between groups and forward/backward span: F(2, 58) = 5.74, MSE = .39, p     

Pharmaceutical Benefits Advisory Committee: some questions answered

BACKGROUND: The butterfly-shaped dystrophy of the macula is an extremely rare autosomal dominant retinal disorder first described by Deutman in 1970. Two cases are presented. CASE REPORTS: The first patient presented to the clinic with slight deterioration of vision OD. Corrected visual acuity was OD 0.63 and OS 0.8. Examination of anterior segments was normal bilaterally. Funduscopically there was a mild disturbance of the foveolar retinal pigment epithelium. Fluorescein angiography, however, disclosed a large pattern-like hypofluorescence with hyperfluorescent areas in the macular region. Visual fields and electroretinography were normal. The second patient complained of decreased visual acuity OU. Funduscopic and angiographic findings were similar to the first patient. CONCLUSION: Different forms of pattern dystrophies of the macula have been described in the literature with moderate visual impairment. Differentiation is sometimes difficult as some forms have been reported to occur in one family. They may represent different clinical entities of the same disease. Diagnosis is usually made by fluorescein angiography.     

Voluntary facial expression of emotion: Comparing congenitally blind with normally sighted encoders.

The ability of congenitally blind persons to produce voluntarily facial expressions of a number of emotions was compared with that of normally sighted individuals using both objective facial measurement and observer recognition. Results revealed that there were almost no significant differences between blind and sighted participants with respect to the number and type of facial action units produced. The portrayals of the blind participants were significantly more poorly recognized by observers than were those of the sighted participants (except for happiness). Correspondence analyses of the data showed differences between sighted and blind participants in the dimensional structure of the expressions (as based on the similarity among emotions with respect to both objective measurement and judgments). Overall, the data relativize earlier conclusions on the facial expression of blind as compared with sighted persons and suggest specific hypotheses and procedures for further work in this area. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Polysomnographic sleep is not clinically impaired in Vietnam combat veterans with chronic posttraumatic stress disorder

BACKGROUND: Because sleep is typically disturbed in posttraumatic stress disorder (PTSD), this study was undertaken to evaluate a group of Vietnam combat veterans with the disorder using clinical polysomnographic techniques. METHODS: Eighteen Vietnam combat veterans with PTSD and 10 healthy non-combat-exposed Vietnam era veterans participated in 2 nights of polysomnographic study and a multiple sleep latency test. RESULTS: No significant differences between subjects and controls were noted except for greater sleep onset latency to stage 2 (p < .03), and lower arousals/hour from stages 3 & 4 (p < .04) on night 2, and lower subjectively estimated total sleep time on night 1 (p < .005) in the case of PTSD subjects. Otherwise, results from the second night served to replicate those from the first, and no significant differences appeared on 2 successive nights for any polysomnographic variable. No daytime hypersomnolence was detected. CONCLUSIONS: Polysomnographically recorded sleep was notably better than expected in the presence of clinically significant PTSD with typical histories of disrupted sleep. In these subjects, there is no clinically significant sleep disorder or typical pattern of sleep disturbance detectable by standard polysomnography.     

Facial expressions and social responsiveness of blind monkeys.

Conducted 3 experiments with 5 blind and 5 sighted crab-eating monkeys (Macaca fascicularis), and their offspring to (a) test the role of auditory and visual information in attraction of an infant to its mother, (b) determine whether blind infants preferred their mothers to a mother from another group when both females were fully sedated, thus eliminating auditory and visual cues, and (c) assess the frequency and character of social interactions and facial expressions of blind Ss. Results of the 3 experiments show that tactual and perhaps auditory cues maintain the social affinity of blind juvenile monkeys. Olfactory discrimination of individuals was also tested, but not demonstrated. Facial expressions were essentially normal in form, but in some cases they occurred at different frequencies than those of sighted animals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bias and bulimia nervosa: how typical are clinic cases?

OBJECTIVE: Since patients being treated for bulimia nervosa constitute only a minority of persons with the disorder, the cases seen in clinics may be subject to sampling bias. The aim of this study was to investigate sampling bias as it affects secondary referrals for bulimia nervosa. METHOD: The personal and family characteristics of a consecutive series of 60 women with secondary referrals for bulimia nervosa (clinic subjects) were compare with those of 83 subjects with bulimia who were recruited directly from the community. Most of the data were collected by interview. RESULTS: The demographic characteristics of the two groups were similar. The clinic subjects had a more severe eating disorder and much greater impairment of social functioning. There was no difference between the groups in duration of the eating disorder or level of general psychiatric disturbance. The community subjects were heavier and had stronger family histories of obesity. CONCLUSIONS: There is sampling bias among secondary referrals for bulimia nervosa. The relative absence of persons prone to obesity among secondary subjects is important, since there is evidence that vulnerability to obesity is a poor prognostic feature as well as being a risk factor for the development of bulimia nervosa. The greater social impairment among the clinic subjects is suggestive of greater personality disturbance in this group. Caution is warranted when generalizing from clinic cases to the disorder as a whole.     

Effect of strength training on EMG of human skeletal muscle

An 8-year-old white girl with a history of vertigo, nausea, and vomiting developed a progressive hearing loss, bilateral retinal arteriolar narrowing in each eye, vasoproliferation, and subsequent intravitreal hemorrhage. An attempt at peripheral retinal ablation with cryotherapy in the left eye resulted in retinal detachment. Spontaneous retinal detachment occurred in the right eye and was successfully repaired. Repeated intermittent hemorrhages occurred despite intraocular diathermy. Three years after onset, visual acuity was R.E.: 6/21 (20/66) and L.E.: light perception. She remains totally deaf. A 20-year-old white woman developed severe bilateral sensorineural hearing loss with poorly functioning labyrinths, followed by midperipheral retinal arteriolar occlusions and vasoproliferation on the optic nerve head. Progressive retinal neovascularization was followed by rubeosis iridis and repeated episodes of intravitreal bleeding. Six years after onset, visula acuity was R.E.: hand motions, and L.E.: 6/3 (20/100). She remains totally deaf. Both patients were of normal gestation, development, and mentality, without evidence of other systemic disease. The cause of this disease was not found.     

Endocrinologic and metabolic complications of Alagille syndrome]

BACKGROUND: First language acquisition depends on intermodal perception, especially auditive, tactile-kinesthetic, and partly visual in addition to sensomotoric integration. The influence of the vestibular function for a physiological language development is still unknown. PATIENT: A case history of a child with bilateral aplasia of all semicircular canals, normacusis in the right ear, and severe sensorineural hearing loss in the left (hearing aid supplied), without mental deficiency, allows us to draw initial conclusions. RESULTS: Logopedic diagnostics revealed only a mild articulation disorder (interdental sigmatism, inconstant gammacism) as a possible consequence of recurrent middle ear effusions since early childhood. Language development diagnostics did not demonstrate any significant norm deviation. CONCLUSIONS: In contrast to the statomotoric disorder, no evidence for a specific language impairment was found. Our report elucidates the importance of a selected diagnostic imaging (spiral CT and MIP MRI) in the phoniatric-ped-audiological field.     

Numerical estimation in blind subjects: Evidence of the impact of blindness and its following experience.

Vision was for a long time considered to be essential in the elaboration of the semantic numerical representation. However, early visual deprivation does not seem to preclude the development of a spatial continuum oriented from left to right to represent numbers (J. Castronovo & X. Seron, 2007; D. Szücs & V. Csépe, 2005). The authors investigated the impact of blindness and its following experience on a 3rd property of the mental number line: its obedience to Weber's law. A group of blind subjects and a group of sighted subjects were submitted to 2 numerical estimation tasks: (a) a keypress estimation task and (b) an auditory events estimation task. Blind and sighted subjects' performance obeyed Weber's law. However, blind subjects demonstrated better numerical estimation abilities than did sighted subjects, especially in contexts involving proprioception, indicating the existence of better mapping abilities between the symbolic representations of numbers and their corresponding magnitude representations, obeying Weber's law (e.g., J. S. Lipton & E. Spelke, 2005). These findings suggest that blindness and its following experience with numbers might result in better accuracy in numerical processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparaison des modèles de préférence manuelle d'enfants aveugles et d'enfants voyants.

Studied differences in manual preferences in blind and sighted children. Ss were 55 congenitally blind children (aged 7–13 yrs) and a comparison group of 64 sighted children (aged 6–12 yrs). Ss were observed while performing 12 manual activities, including pointing and using various familiar objects. Intercorrelations among manual preferences for the different activities were analyzed, and intergroup differences were determined. Results for normally right-handed and normally left-handed Ss were compared. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Brain lateralization and severity of stuttering in children

Cerebral lateralization in visual perception was investigated in 9 severe stuttering, 11 mild stuttering and 48 fluent speakers. The subjects were asked to identify words presented in the left or right visual field for 20 ms. Children responded by pointing to the exposed test word on a response card which contained four different words. Errors committed in the left and right visual fields were analyzed. The data showed a left hemisphere superiority in the processing of words in both the mild stutterers and the fluent speakers, but a right hemisphere advantage in the severe stutterers. The results suggest a close relationship between the severity of stuttering and functional brain organization.