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PubMed1993

Nerve growth factor facilitates regeneration across nerve gaps: morphological and behavioral studies in rat sciatic nerve.

The rat sciatic nerve does not possess a high potential for regeneration through silastic tubes when the interstump nerve gap is greater than 10 mm. In this study, the effect of NGF treatment on regeneration of the rat sciatic nerve in 10- and 15-mm silastic chambers was compared. In addition, regeneration in 15-mm silastic chambers was compared to regeneration in 15-mm semipermeable chambers. Sections of tubing were implanted and filled with NGF or a control solution of cytochrome C (Cyt. C). Tube implants were removed at various postoperative times and regeneration was assessed histologically and behaviorally. NGF treatment promoted regeneration success rate. It enhanced the initial outgrowth of nonneuronal cells and neuronal fibers into the chamber producing more cellular, organized regenerates. At 2 weeks, in 10-mm chambers, NGF-treated regenerates had fourfold more unmyelinated fibers than controls. At 3 weeks, NGF-treated regenerates possessed threefold more myelinated fibers than controls. After 4 weeks all regenerates had similar numbers of myelinated nerves at the chamber's midpoint. This initial "head start" was sustained peripherally as indicated by the earlier return of sensory function (response to a noxious temperature stimulus) in NGF-treated animals. Finally, regeneration success rate in 15-mm semipermeable tubes is greater than that in 15-mm silastic chambers (NGF and Cyt. C). However, regenerates in silastic chambers possessed twofold more myelinated fibers than regenerates in semipermeable chambers. The positive effects of NGF on neural regeneration and recovery of sensory function provide support for the potential use of NGF in treating peripheral nerve injuries.

Animals↗

PubMed1999

Experimental fetal neurosurgery: effects of in-utero manipulations on somatosensory evoked potentials.

Somatosensory evoked potentials (SEP) were used to objectively evaluate sensory function in neonatal sheep after experimental fetal surgery. Posterior tibial (PTN) and ulnar (UN) nerves were stimulated electrically and averaged SEP were recorded from scalp electrodes placed over the somatosensory cortex. Animals with experimentally-created myelomeningocele (MMC) showed no SEP to PTN stimulation, but normal SEP to UN stimulation. In-utero repair of the MMC resulted in preservation of neurologic function and normal PTN SEP. In-utero thoracic spinal-cord transection resulted in no regeneration, and no SEP to PTN stimulation. In-utero unilateral transection of the sciatic nerve, even with attempted repair, resulted in little or no regeneration and absent or grossly abnormal PTN SEP from the affected side. In summary, the SEP technique provides valuable information concerning preservation of sensory function in a variety of experimentally created neurologic abnormalities and can aid in functional evaluation of experimental therapeutic fetal interventions.

Animals↗

PubMed2005

Induction of photosensitivity by heterologous expression of melanopsin.

Melanopsin has been proposed to be the photopigment of the intrinsically photosensitive retinal ganglion cells (ipRGCs); these photoreceptors of the mammalian eye drive circadian and pupillary adjustments through direct projections to the brain. Their action spectrum (lambda(max) approximately 480 nm) implicates an opsin and melanopsin is the only opsin known to exist in these cells. Melanopsin is required for ipRGC photosensitivity and for behavioural photoresponses that survive disrupted rod and cone function. Heterologously expressed melanopsin apparently binds retinaldehyde and mediates photic activation of G proteins. However, its amino-acid sequence differs from vertebrate photosensory opsins and some have suggested that melanopsin may be a photoisomerase, providing retinoid chromophore to an unidentified opsin. To determine whether melanopsin is a functional sensory photopigment, here we transiently expressed it in HEK293 cells that stably expressed TRPC3 channels. Light triggered a membrane depolarization in these cells and increased intracellular calcium. The light response resembled that of ipRGCs, with almost identical spectral sensitivity (lambda(max) approximately 479 nm). The phototransduction pathway included Gq or a related G protein, phospholipase C and TRPC3 channels. We conclude that mammalian melanopsin is a functional sensory photopigment, that it is the photopigment of ganglion-cell photoreceptors, and that these photoreceptors may use an invertebrate-like phototransduction cascade.

Animals↗

PubMedDate not supplied

Intraoperative monitoring of ischiatic nerve function with sensory evoked potentials.

Serial recordings of sensory evoked potentials (SEP) generated in response to stimulation of each tibial nerve were obtained from 23 anesthetized dogs. Five dogs were anesthetized for 3 hours to evaluate changes in serial SEP during general anesthesia. Nonsurgical and surgical manipulations were performed on one hind limb of five dogs to determine the effects of limb positioning and nerve retraction on SEP. In 13 dogs, the ischiatic nerve was exposed surgically and retracted until the SEP deteriorated and disappeared, to determine the relationship between amount of tension on the nerve and the time to complete deterioration of the SEP. Sensory evoked potential waveforms, which consisted of two to five peaks, were stable throughout the anesthetic period. The first two peaks were the most stable. Latency of the first two peaks was the easiest and most reliable parameter to evaluate. Although the peak latency in recordings from the superior hind limb was always slightly longer, SEP recordings from the inferior limb were good controls to monitor nerve function. There was considerable variation in sensitivity to nerve retraction. The technique proved to be a reliable way to monitor nerve function in normal anesthetized dogs.

Anesthesia, General↗

PubMed2004

Morbidity of harvesting of bone grafts from the iliac crest for preprosthetic augmentation procedures: a prospective study.

It has been the aim of the present prospective clinical study to assess the morbidity following the harvest of bone from the anterior and posterior ilium in elective preprosthetic augmentations. Fifty consecutive healthy patients (30 female, 20 male, mean age 52.5+/-9.3 years, range 31 years to 65 years) underwent augmentations of implant sites by iliac crest bone grafts. The bone harvest was carried out in 25 cases from the anterior and in 25 cases from the posterior ilium. The superficial sensory function of the skin was determined quantitatively preoperatively, 7 and 30 days after surgery with the 'Pain and Thermal Sensitivity' Test (PATH Test). On the same occasions subjective pain on a visual analogue scale (VAS) and gait disturbances were documented. In the PATH Test, for the innervation areas of the lateral femoral cutaneous nerve (LFCN) and the superior and middle cluneal nerves (SMCN) a significant impairment of the superficial sensory function could be found after 1 week and a significant tendency towards recovery after 1 month (warm stimulus(FCNpreop) 37.9+/-3.0 degrees C, warm stimulus(LFCNday7): 38.6+/-3.2 degrees C, warm stimulus(LFCNday30): 37.9+/-2.9 degrees C, P(LFCNwarmpreop/day7)=0.023,P(LFCNwarmpreop/day30) =0.886, warm stimulus(SMCNpreop): 36.1+/-2.4 degrees C, warm stimulus(SMCNday7): 36.6+/-2.3 degrees C, warm stimulus(SMCNday30): 36.3+/-4.0 degrees C,P(SMCNwarmpreop/day7) <0.0005,P(SMCNwarmpreop/day30) =0.086). Gait disturbances were seen in seven patients after anterior and in three patients after posterior bone harvest 7 days after surgery (P(gaitdisturbanceanterior/posterior)=0.123). After 1 month none of the patients of both groups showed gait disturbances any longer. The maximum subjective pain level was found on the second postoperative day in both groups. It was significantly higher for the anterior approach (VAS(anteriorday2) 7.0+/-1.5, VAS(posteriorday2) 5.5+/-1.8,P(VASanterior/posteriorday2) =0.004). At day 7 and at day 30, the pain levels did no longer differ significantly (VAS(anteriorday7) 3.7+/-1.4, VAS(posteriorday7) 3.2+/-1.6,P(VASanterior/posteriorday7) =0.165, VAS(anteriorday30) 1.4+/-0.7, VAS(posteriorday30) 1.4+/-0.8,P(VASanterior/posteriorday30) =0.724). Because of the lower morbidity of bone harvest from the posterior ilium in the early postoperative phase compared to the anterior approach it seems that it should be preferred in elective augmentation procedures.

Adult↗

PubMed1984

[A case report of post-traumatic syringomyelia].

A case of posttraumatic syringomyelia which appeared 26 years after the injury was presented. A patient was 61 year old female, who sustained thoraco-lumbar spine injuries rendering her to paraplegic in 1954. Eleven months later she had an operation of T6-T9 and L1-L2 laminectomies and regained motor and sensory functions of the both lower extremities. She was ambulatory with crutches till 1979. In 1980, burning pain was noticed in the left scapular region, and thereafter, extended to the ulnar side of the left forearm. The pain became progressively worse and intractable. Analgesics were ineffective. Two years later muscle atrophies and weakness in the left finger intrinsic muscles appeared. Absent deep tendon reflexes in the left upper extremity, dissociated sensory loss (in the left C2-S1 and right T5-T12 dermatomes) and paraparesis were also documented. Metrizamide CT scan performed 24 hours after the intrathecal injection disclosed an intramedullary syrinx between C2 and L1 vertebral levels. No communication with the fourth ventricle was seen. A syringoperitoneal shunt with low pressure valve was placed. The pain subsided immediately after this procedure. However, no improvement in motor and sensory functions were observed. Pathophysiological mechanisms involved in post-traumatic syrinx formation and its development were discussed. We prefer hypothesis proposed by Ball and Dayan to Gardner's hydrodynamic theory regarding to development of the syrinx secondary to spinal cord injury.

Female↗

PubMed1996

Recovery of sensation in the radial forearm free flap in oral reconstruction.

The purpose of this study was to find out to what extent sensory function recovers in a free radial forearm flap used for intraoral reconstruction after surgery for oral cancer. In 40 free radial forearm flaps we investigated the perception of light touch, two-point discrimination, pain, directional sensation, and temperature between 6 months and 11 years after flap transfer to the oral cavity. Four flaps (10 percent) were anesthetic, 21 flaps (52.5 percent) recovered partly, and 15 flaps (37.5 percent) had perception of all sensory modalities tested in at least two-thirds of the flap area. All patients with positive sensation in the surrounding area subsequently had good sensory recovery in the flap. This suggests that recovery of sensation in a nonreinnervated free flap is due to nerve ingrowth from the surrounding mucosa. The present results suggest that sensory function in intraoral free radial forearm flaps returns again. Further study is necessary to define the use of neurofasciocutaneous radial forearm flaps in reconstruction of the oral cavity.

Carcinoma, Squamous Cell↗

PubMed2002

Morbidity of harvesting of retromolar bone grafts: a prospective study.

20 retromolar bone grafts were harvested in outpatients for augmentation of the implant site from January to June 2000 (10 female, 10 male, 40.9 +/- 12.8 years, minimum 17 years, maximum 66 years). The aim of the study was to assess typical complications of this procedure in a prospective manner. For the determination of the superficial sensory function of the inferior alveolar and the lingual nerve, an objective method was used. The bone grafts were harvested for single tooth reconstruction. In 14 cases a ridge augmentation and in 6 cases an endoscopically controlled crestal sinus floor elevation was performed. Preoperatively, the height of bone above the cranial aspect of the inferior alveolar nerve in the retromolar region was assessed radiologically with known markers. The maximum mouth opening was determined. The superficial sensory function of the inferior alveolar and the lingual nerve was assessed with the Pointed-Blunt Test, the Two-Point-Discrimination Test and the objective method of the 'Pain and Thermal Sensitivity' Test (PATH Test). Moreover, the pulp sensitivity of the teeth of the donor site was determined by cold vitality testing. All tests were repeated 1 week postoperatively. Intraoperatively, the width of the retromolar region was measured with a caliper. The patients rated the operative strain on a visual analogue scale. The height of bone above the inferior alveolar nerve in the retromolar region was 11.0 +/- 2.2 mm. The width of the retromolar area was 14.2 +/- 1.9 mm. Postoperatively, the maximal mouth opening changed significantly (40.8 +/- 3.5 mm preoperatively, 38.9 +/- 3.7 mm postoperatively, P = 0.006). However, the reduction was not relevant clinically. A direct injury of the inferior alveolar or lingual nerve did not occur. A sensitivity impairment could not be detected for either of the nerves by the different test methods 1 week postoperatively. The operative strain related to the donor site was significantly less than the strain generated by the implant placement (rating on a visual analogue scale 2.8 +/- 1.0 and 4.1 +/- 2.0, respectively, P = 0.027). Retromolar bone grafts are a viable method for augmentation of the implant site in conjunction with single tooth reconstruction with low strain on the patient and minimal risk of complications.

Adolescent↗

PubMed2006

Changes in joint position sense after conservatively treated chronic lateral ankle instability.

Improvement of ankle proprioception through physiotherapy (a.k.a. proprioceptive training) is a widely accepted conservative treatment modality of chronic functional lateral ankle instability. Clinical studies provided controversial data on its proprioceptive effect. Aim of this study was to gain evidence on the efficacy of proprioceptive training on ankle joint position sense. Ten patients (five males and five females, aged 23.3+/-5.4 years) were treated conservatively for chronic lateral ankle instability with a special training programme over 6 weeks. For the assessment of joint position sense we used the slope-box test, first applied and described by Robbins et al. (Br J Sports Med 29:242-247, 1995). The test was performed before the start and after the end of the training programme, measuring joint position sense on 11 different slope amplitudes in four directions (anterior, posterior, lateral and medial) in random order each on both ankles. Comparisons were made between pre- and post-training results as well as versus a control-group of ten healthy athletes. Overall the proprioceptive sensory function of the studied group has improved, but this improvement was not significant in all directions. Only two patients have shown significant improvement of joint position sense in all directions (mean estimate error improvement: 2.47 degrees ), while conservative treatment was partially successful in five others (mean estimate error improvement: 0.73 degrees ). The follow-up results of these seven patients were comparable with the values measured in the control-group. Three patients did not show any improvements (mean estimate error improvement: -0.55 degrees ) (overall difference between improving and non-improving patients: P<0.0001). Mean absolute estimate error profiles of the seven improving patients became similar to the profiles of healthy athletes, while these changes could not be observed in the case of the three non-improving participants. Proprioceptive rehabilitation programme can be an effective method in order to improve impaired joint position sense function. After 6 weeks non-responding patients can be well identified, and considered for other treatment modalities. The determination of the effective length of the programme however needs further evaluation. Still, changes in the proprioceptive sensory function of the ankle plantarflectors indicate the preventive effect of the training programme. Furthermore, our results support the theory of simultaneous function of different mechanoreceptor-systems.

Adult↗

PubMed1986

Pure-tone thresholds, speech understanding, and their correlates in samples of men of different ages.

Pure-tone thresholds and speech understanding were studied in three samples of men of different ages (31-35, 51-55 and 71-75 years). The air-conducted pure-tone thresholds were measured at 125-8,000 Hz and speech understanding by the help of interrupted and masked speech tests. The audiological measures were related to measures of other sensory functions, psychomotor speed, cognitive functions, psychic well-being, occupational and educational background and health. The results indicated a clear decrement in all audiological measures when proceeding from younger to older age groups. The results of the speech-understanding tests correlated significantly with the pure-tone thresholds both at 4,000 Hz and at the mean of three frequencies (500, 1,000, 2,000 Hz) in the speech area. The audiological measures were not associated with other sensory functions or psychic well-being but showed significant correlations with psychomotor speed and cognitive functions. The most important predictors of the auditory functions within the age groups were occupational status, noise exposure at work, cognitive capacity, education, and number of disease symptoms, which, in addition, correlated with each other.

Adult↗

PubMedDate not supplied

The mystery of structure and function of sensory processing areas of the neocortex: a resolution.

Many different neural models have been proposed to account for major characteristics of the memory phenomenon family in primates. However, in spite of the large body of neurophysiological, anatomical and behavioral data, there is no direct evidence for supporting one model while falsifying the others. And yet, we can discriminate models based on their complexity and/or their predictive power. In this paper we present a computational framework with our basic assumption that neural information processing is performed by generative networks. A complex architecture is 'derived' by using information-theoretic principles. We find that our approach seems to uncover possible relations among the functional memory units (declarative and implicit memory) and the process of information encoding in primates. The architecture can also be related to the entorhinal-hippocampal loop. An effort is made to form a prototype of this computational architecture and to map it onto the functional units of the neocortex. This mapping leads us to claim that one may gain a better understanding by considering that anatomical and functional layers of the cortex differ. Philosophical consequences regarding the homunculus fallacy are also considered.

Afferent Pathways↗

PubMed2005

Risk factors for accommodative esotropia among hypermetropic children.

PURPOSE: Identification of risk factors for accommodative esotropia may help to determine which children with hyperopia may benefit from early spectacle correction or preventive therapy. METHODS: Participants in the family history study were 95 consecutive patients, aged 18 to 60 months, with accommodative esotropia. Participants in the binocular sensory function study were a subgroup of 41 children enrolled in the family history study within 1 month of onset, while the esodeviation was still intermittent. Participants in the hypermetropia study were 345 consecutive patients, ages 12 months to 8 years, with refractive error of +2.00 D or greater and no esodeviation before age 12 months. RESULTS: In the family history study, 23% of children with accommodative esotropia had an affected first-degree relative, and 91% had at least one affected relative. In the binocular sensory function study, random-dot stereoacuity was abnormal in 41% of children, whereas an abnormal motion VEP, Worth 4-dot, or positive 4-PD base-out prism responses were present in 4% or less of the children. In the hypermetropia study, patients with a mean spherical equivalent of < +3.00 D and significant anisometropia had a 7.8-fold increased risk for accommodative esotropia over nonanisometropic patients. CONCLUSIONS: A positive family history, subnormal random-dot stereopsis, and hypermetropic anisometropia each pose a significant risk for the development of accommodative esotropia. Assessment of these risk factors in conjunction with refractive screening should help to identify those children who are most likely to benefit from early spectacle correction or preventive treatment.

Accommodation, Ocular↗

PubMed2006

Trigeminal sensory pathway function in patients with SUNCT.

OBJECTIVE: Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) is a rare primary headache whose origins are unclear. To seek information on its pathophysiology, we studied the trigeminal Abeta and Adelta pathways by recording trigeminal reflexes and laser evoked potentials (LEPs) in patients with SUNCT. METHODS: Trigeminal reflexes and LEPs were recorded in 11 consecutive patients. Ten patients had neuroimaging evidence documenting idiopathic SUNCT and one had a posterior fossa tumour that compressed the trigeminal nerve thus causing symptomatic SUNCT. RESULTS: Whereas the patients with idiopathic SUNCT had normal trigeminal reflex and LEP responses, the patient with symptomatic SUNCT had abnormal responses. CONCLUSIONS: Our neurophysiological findings show that idiopathic SUNCT spares the trigeminal sensory pathways whereas symptomatic SUNCT does not. SIGNIFICANCE: Neurophysiological testing can easily differentiate the idiopathic and symptomatic forms of SUNCT. It also suggests that the two forms are pathophysiologically distinct entities.

Adult↗

PubMed1997

Intravenous regional anesthesia. Evaluation of 4 different additives to prilocaine.

Intravenous regional anesthesia (IVRA) is an effective method of producing anesthesia of the extremities. Disadvantages are the rapid loss of anesthesia after the deflation of the tourniquet and the rapid development of postoperative pain. This study compared the effect of four different additives to prilocaine with saline on the development of a complete sensory block, on the return of sensory function after deflation of the tourniquet and on the development of postoperative pain after IVRA for minor orthopedic surgery of the arm. Seventy-five patients, ASA class 1 or 2, were randomly divided into 5 groups. All patients received 30 ml. of prilocaine 1%, together with 5 ml. of additive. In group 1, the additive was saline, in group 2 bupivacaine 0.25%, in group 3 clonidine 150 micrograms in saline, in group 4 sufentanil 25 micrograms in saline and in group 5 tenoxicam 20 mg. The development of a complete sensory block proved significantly faster in the patients receiving sufentanil (4.8 min.) as compared to plain prilocaine (7.5 min.). The return of the sensory function was comparable for all groups. Postoperative pain scores were significantly better in the clonidine and tenoxicam groups.

Adjuvants, Anesthesia↗

PubMed1989

Expression of achaete and scute genes in Drosophila imaginal discs and their function in sensory organ development.

Several kinds of sensory organs (SOs) appear in stereotyped positions on the adult Drosophila cuticle. The generation of these SOs requires the activity of the achaete (ac) and scute (sc) genes. To investigate whether ac and sc also provide spatial information for the positioning of SOs, we have analyzed the patterns of expression of these genes in the wing imaginal disc around the time that SO precursors are being specified. We find that expression coincides with and is restricted to areas of the disc where these precursors are known to be located. In the loss-of-function sc mutant, sc RNA is depleted in a single area located in the region where the precursor for the suppressed macrochaeta should be found. Moreover, some, and probably all, SOs require expression of these genes to reach the earliest detectable differentiated state. These and other results presented here, together with the finding that expansion of the areas of ac and/or sc expression causes the development of ectopic SOs, indicate that ac and sc promote the determination of SO precursors and delimit the regions of the imaginal discs where they can develop.

Animals↗

PubMed1999

Post-traumatic distal nerve entrapment syndrome.

Eleven patients with paralysis of muscle groups in the upper or lower extremity were clinically diagnosed after previous proximal direct trauma to the corresponding peripheral nerves, without complete nerve disruption. Patients were seen within an average of 8 months after trauma (minimum 3 months and maximum 2 years after). Nerve lesions were caused either by gunshot, motor-vehicle accident, and other direct trauma or, in one case, after tumor excision. All patients presented with complete sensory and motor loss distal to the trauma site, but demonstrated a positive Tinel sign and pain on testing over the "classic" (distal) anatomic nerve entrapment sites only. After surgical release through decompression of the nerve compression site distal to the trauma, a recovery of sensory function was achieved after surgery in all cases. Good-to-excellent restoration of motor function (M4/M5) was achieved in 63 percent of all cases. Twenty-five percent had no or only poor improvement in motor function, despite a good sensory recovery. Those patients in whom nerve compression sites were surgically released before 6 months after trauma had an improvement in almost all neural functions, compared to those patients who underwent surgery later than 9 months post trauma. A possible explanation of traumatically caused neurogenic paralysis with subsequent distal nerve compressions is provided, using the "double crush syndrome" hypothesis.

Adolescent↗

PubMedDate not supplied

MRI in the acute phase of spinal cord traumatic lesions: Relationship between MRI findings and neurological outcome.

PURPOSE: To evaluate the role of emergency MRI in the diagnosis of acute spinal injuries, and to correlate the MRI pattern with the neurological outcome. MATERIALS AND METHODS: Thirty-eight patients with MRI-proven spinal cord injury were classified according to the Frankel classification. MRI was always performed within 8 hours from trauma. Frankel classification divides spinal cord injuries into 5 classes of decreasing severity based on the presence of motor and/or sensory function loss. On the basis of the MRI findings the patients were classified in 3 groups: group 1 (intramedullary haematoma), group 2 (multi-metamer oedema), group 3 (single-metamer oedema). All patients underwent neurosurgery and were clinically evaluated until the stabilization of neurological recovery. Mean follow-up time was 12 months. The MR images were retrospectively evaluated and correlated to the neurological outcome. RESULTS: Twenty-eight patients showed complete motor loss (Frankel classes A and B); of these 28 patients 12 (42.8%) had MRI evidence of intramedullary haematoma, 12 (42.8%) had multi-metamer oedema and 4 (14.4%) had single-metamer oedema. Of the 10 patients with incomplete motor loss, none had MRI evidence of haemorrhage, 4 (40%) showed multi-metamer oedema and 6 (60%) showed single-metamer oedema. Follow-up clinical assessment revealed that 14/38 patients (36,8%) had clinical improvement and 2/38 cases (5%) had a complete motor recovery, as demonstrated by the move to a higher Frankel class. CONCLUSIONS: Our results, consistent with previous reports, confirm a strong correlation between the MRI appearance of traumatic spinal cord injuries in acute phase and long-term recovery of motor and sensory function: patients with initial haemorrhage had a poor prognosis, whereas those with spinal cord oedema had a good clinical outcome, as demonstrated by the passage to a higher Frankel class. MRI is particularly important in the initial evaluation of unconscious patients who cannot undergo a motor and sensory neurological evaluation, and to define the prognosis, which will influence the correct therapeutic choice.

Acute Disease↗

PubMed1993

Visual attention problems as a predictor of vehicle crashes in older drivers.

PURPOSE: To identify visual factors that are significantly associated with increased vehicle crashes in older drivers. METHODS: Several aspects of vision and visual information processing were assessed in 294 drivers aged 55 to 90 years. The sample was stratified with respect to age and crash frequency during the 5-year period before the test date. Variables assessed included eye health status, visual sensory function, the size of the useful field of view, and cognitive status. Crash data were obtained from state records. RESULTS: The size of the useful field of view, a test of visual attention, had high sensitivity (89%) and specificity (81%) in predicting which older drivers had a history of crash problems. This level of predictability is unprecedented in research on crash risk in older drivers. Older adults with substantial shrinkage in the useful field of view were six times more likely to have incurred one or more crashes in the previous 5-year period. Eye health status, visual sensory function, cognitive status, and chronological age were significantly correlated with crashes, but were relatively poor at discriminating between crash-involved versus crash-free drivers. CONCLUSIONS: This study suggests that policies that restrict driving privileges based solely on age or on common stereotypes of age-related declines in vision and cognition are scientifically unfounded. With the identification of a visual attention measure highly predictive of crash problems in the elderly, this study points to a way in which the suitability of licensure in the older adult population could be based on objective, performance-based criteria.

Accidents, Traffic↗