Spatial contrast sensitivity in benign intracranial hypertension.

Spatial Contrast Sensitivity (CS) was studied in 20 patients with benign intracranial hypertension (BIH). At presentation CS loss was found in 43% of the eyes, and impairment of visual acuity attributed to BIH in only 16%. Nine patients had blurred vision or visual obscurations, all of whom had abnormal CS. The clinical application of CS measurement in BIH for monitoring the progression or regression of the disease is illustrated by serial measurements in 11 patients. Progressive visual loss in longstanding papilloedema and improvement of visual function in subsiding papilloedema can occur without any change in Snellen acuity or visual field charting.     

Drug therapy for acquired pendular nystagmus in multiple sclerosis

Acquired pendular nystagmus (APN) is regularly accompanied by oscillopsia and impairment of static visual acuity. Therapeutic approaches to APN remain controversial, and there is no generally accepted therapeutic approach. We tested 14 patients who had suffered from APN caused by multiple sclerosis for several years; 12 patients presented with fixational pendular nystagmus (increasing during fixation) and 2 with spontaneous pendular nystagmus. All 11 patients with fixational pendular nystagmus who were given memantine, a glutamate antagonist, experienced complete cessation of the nystagmus. In contrast, scopolamine caused no (6 of 8) or only a minor (10–50%) reduction of the nystagmus (2 of 8). It was concluded that memantine is a safe treatment option for APN. Received: 29 August 1995 Received in revised form: 6 August 1996 Accepted: 19 August 1996     

Benign intracranial hypertension: correlation of cerebral blood flow with disease severity

Benign intracranial hypertension (BIH) is characterized by symptoms and signs of raised intracranial pressure in the absence of an intracranial mass lesion, infection or hydrocephalus. The purpose of this study was to evaluate the effect of disease severity on cerebral blood flow in patients with BIH on acetazolamide therapy. METHODS: 11 patients (nine females, two males; mean age 30.5 years; range 22-29 years) with BIH were studied. All patients underwent CT and MRI scanning which were normal. The CSF pressure of all patients was above 200 mm H2O. All patients were under treatment with acetazolamide (1 g/day). Disease severity was determined by visual field examination and by clinical symptoms. Five patients were categorized into mild to moderate BIH (group I) and six patients had severe BIH (group II). All patients underwent perfusion brain SPECT with 740 MBq of Tc-99m-HMPAO. RESULTS: Brain perfusion abnormalities were observed in six of the 11 patients. One out of five patients in group I (20%) and five out of six patients (83%) in group II, had abnormal SPECT findings (P<0.04). In four patients of group II the left parietal lobe was involved and another patient had a right occipital abnormality. The single patient from group I with SPECT abnormalities demonstrated focal decreased perfusion in the left temporal area and decreased perfusion in the left caudate nucleus. CONCLUSION: Patients with severe degree of BIH have a higher incidence of cerebral perfusion abnormalities. This group may have an increased risk of cerebrovascular complications. The continuous administration of acetazolamide which affects the vascular autoreactivity may contribute to the regional hypoperfusion. Further studies are recommended to evaluate the natural course of disease versus iatrogenic treatment effects.     

Differential effectiveness of EMG-feedback versus combined EMG-feedback and relaxation instructions in the treatment of tension headache

After a 2$\text{1}\text{2}$ week baseline period 18 muscle tension headache patients were randomly assigned to one of three conditions: waiting list, formal EMG-feedback training, combined training of EMG-feedback and progressive relaxation. Patients in the two treatment conditions obtained 12 training sessions and returned 3 months after treatment for a follow-up session. Both treatment conditions were equivalent in their effect on EMG of m. frontalis and on headache scores, against stability for waiting list patients as observed in a separate analysis. Changes over treatment in both parameters were significantly correlated. Among changes in headache subparameters, the only significant correlation with changes in frontalis EMG was found for duration of pain. In both treatment conditions a generalizing effect to neck muscles was observed. Among personality variables decreases were found in neuroticism and somatization at follow-up for the combined training condition, whereas the EMG-feedback alone condition remained unaltered. The combined training condition also proved superior in reducing operant pain behavior.     

The contribution of the corpus callosum to receptive fields in the lateral suprasylvian visual areas of the cat

In both ordinary cats and ‘Boston’ Siamese cats the visual areas in the lateral parts of the middle and posterior suprasylvian gyri (LSA) contain an extensive representation of the ipsilateral half of the visual field. In addition, in both groups of cats the overwhelming majority of neurons in LSA can be driven from both eyes. In Siamese cats this binocular interaction is in marked contrast with what is found in area 17 where neurons are almost exclusively activated through the contralateral eye. Transection of the posterior $\text{1}\text{3}$ to $\text{1}\text{2}$ of the corpus callosum had a different effect on the physiological organization of LSA in the two types of cats. In ordinary cats it caused the loss of the ipsilateral hemifield representation in the eye ipsilateral to the side of recording and reduced this representation in the other eye. However, after the section of the corpus callosum LSA neurons remained binocular. In Siamese cats the callosal transection left the representation of the ipsilateral hemifield in LSA unaffected, but totally abolished the input from the ipsilateral eye. These findings suggest that the visual callosal input to LSA has a different functional significance in ordinary and Siamese cats. In the former cats it may be related to perceptual equivalence across the vertical meridian of the visual field, whereas in the latter cats it may subserve interocular equivalence.     

Serum myoglobin in muscular dystrophy and carrier detection

Serum myoglobin was measured by radioimmunoassay in 143 patients with various muscle diseases including 55 boys with Duchenne dystrophy, 56 carriers of the Duchenne dystrophy gene, 8 carriers of the Becker dystrophy gene, 60 first-degree relatives of patients with sporadic (non-genetically transmitted) muscle diseases and 85 normal controls.A significant difference (P < 0.001) was found between the serum myoglobin levels in normal control men ($\text{x}\text{?}\text{= 31.7}$ range 10–70 μg/l) and those in women ($\text{x}\text{?}\text{= 17.2}$ range 4–27 μg/l) but no difference was found between the controls and relatives of patients with muscle disease. Up to the age of 60 years, no correlation was found between age and serum myoglobin levels in controls. However, levels in boys with Duchenne dystrophy were found to increase slightly up to the age of 10 years and to decrease thereafter. No correlation was found between serum myoglobin and creatine kinase activity in these boys but in Duchenne carriers correlation was close (P < 0.001). Eighteen of 23 definite and 13 of 33 possible carriers of Duchenne dystrophy had myoglobin concentrations above the equivalent normal range. Of those carriers with elevated myoglobin levels, 7 definite and 4 possible carriers had normal serum creatine kinase activity. This was equivalent to an improvement in “detection” of 31% and 12% in these groups of carriers. Of the 8 Becker dystrophy carriers, 6 had elevated myoglobin but all had normal creatine kinase levels.It appears that measurement of serum myoglobin as well as creatine kinase activity may be of great benefit to carrier detection programmes, but the need to establish accurately the extent of normal variation in women is emphasized.     

Pattern evoked potentials in human albinism: Evidence of two different topographical asymmetries reflecting abnormal retino-cortical projections

In fifteen subjects with oculo-cutaneous or ocular albinism pattern-reversal visual evoked potentials (VEP) were recorded to monocular whole-field (16° radius) and right and left vertical half-field (16° radius) stimulation from an array of occipital electrodes.In all 15 subjects the VEP was of low amplitude and the monocular response to whole-field stimulation showed abnormal asymmetry in scalp topography. This asymmetry was similar to that produced by stimulation of the temporal half-field in the same eye. Two distinct types of VEP asymmetry were readily identified in different subjects. In 5 the major positivity of the response ($\text{P100}$) was distributed in the channels ipsilateral to the stimulated eye or temporal half-field, being similar in distribution to the $\text{P100}$ from the temporal hemifield of normal individuals. In 9 other subjects the converse occurred; the $\text{P100}$ was distributed contralaterally. The remaining subject was unique in that the responses from each eye had a distribution that resembled one of the two main groups. The nasal half-field responses also differentiated the two groups. On stimulation of the nasal field in the first group the $\text{P100}$ was usually absent or attenuated and when present it had the same topography as the temporal half-field $\text{P100}$. In contrast the nasal half-field $\text{P100}$ from the second group was always present and, although almost invariably smaller than the temporal half-field $\text{P100}$, it had an identical distribution.There was no correlation between these two patterns of VEP asymmetry and clinical or known genetic features.The findings confirm that in human albinos each hemisphere receives a predominantly monocular input from the contralateral eye; i.e. in addition to the temporal half-field, approximately 20° of the nasal half-field is projected to the hemisphere contralateral to each eye and not, as in normal subjects, to the ipsilateral hemisphere. Furthermore, the finding of two distinct and in some respects opposite types of VEP topographical asymmetry raises the possibility of two variants of the geniculo-cortical projection patterns existing in human albinos similar to those described in the Siamese cat.     

Psychosocial disability during maintenance hemodialysis

Overall psychosocial functioning was assessed in 21 maintenance hemodialysis patients. The Ruesch Social Disability Scale, which provides an overall Social Disability (DS) score as well as subscores for Physical Impairment (PI), Behavioral Impairment (BI), and Social Modifiers (MS), was utilized. A majority of the patients (13) experienced Major Social Disability and the mean DS score of this sample was in the Major Social Disability range ($\text{x}$ = 52.1 ± 10.9). There were no differences between the mean DS score of men and women. Married patients had DS scores significantly lower than those who were divorced or never married (P < .05). Patients with more than five years of maintenance hemodialysis had a mean DS score significantly higher than those with less then five years of maintenance hemodialysis (P < .03). In those patients with more than five years of hemodialysis, the MS scale was significantly elevated (P < .01) in comparison with their counterparts, whereas the BI and PI scores were not different. The data suggest that serious psychosocial impairment is a common sequela of maintenance hemodialysis, especially for long-term patients and those who are not married. Therapeutic approaches directed toward improved social functioning are indicated.     

Learning in rhesus monkeys after amygdalectomy in infancy or adulthood

This study examined the learning abilities of mature rhesus monkeys that had been subjected to bilateral amygdalectomy either during infancy or adulthood. At $\text{4}\text{1}\text{2}$ years of age, 6 female monkeys that had been amygdalectomized in infancy and 12 neurologically intact controls were trained on a barpress avoidance problem. At 6 years, half the controls were amygdalectomized. At $\text{7}\text{1}\text{2}$ years, the infant-operated, adult-operated and control monkeys were trained on shock-motivated problems, including a panelpress avoidance and 15 position reversals, and food-motivated problems, including delayed alternation and 15 position reversals.Infant-amygdalectomized monkeys required significantly more sessions than controls to meet the barpress avoidance criterion at $\text{4}\text{1}\text{2}$ years, and they also took longer to extinguish the response. At $\text{7}\text{1}\text{2}$ years, neither the infant- nor the adult-operated monkeys exhibited any difficulty with the shock-motivated problems. On the food-motivated problems, however, both amygdalectomy groups made more perseverative errors than the controls.The cumulative results from this study and from previous studies with these animals suggest that amygdalectomy in infancy produces no long-term sparing of function in monkeys. When infant- and adult-operated monkeys are tested at the same age, their deficits are indistinguishable.     

Follow-up of stealing behavior in 27 youths after a variety of treatment programs

Case histories are presented of 27 youngsters who had a major problem of stealing. The effectiveness of eight different treatments is examined in terms of proportion of follow-up time spent stealing. (Duration of follow-up was always more than 2 yr.) Clients given Individualized Combined Treatment spent $\text{2}\text{1}\text{2}\text{\%}$ of follow-up time stealing, compared with 46% after other types of treatment.     

The visual evoked potential during development of focal epilepsy

Using the intracortical hemoglobin model for focal epilepsy, changes in the visual evoked potential were evaluated during epileptogenesis in guinea pigs. The amplitude of the late components of the evoked potential exhibited a transient increase in all animals during the first few weeks and, $\text{1}\text{1}\text{2}$ months later, a second sustained increase was seen in 41%. In 71% of these this sustained increase preceded, by 1–2 weeks, photic induced focal spike activity. The late components of the visual evoked potential reflect the same excitability state which is responsible for focal epileptogenesis in visual cortex and may be useful in predicting the development of seizures following head trauma.     

Degradation of human plasma fibrin stabilizing factor XIII subunits by human granulocytic proteinases

Decreased activity of fibrin stabilizing factor XIII may occur in diseases with enhanced destruction of granulocytes. Haemorrhage and impaired wound healing may result. It has been shown by means of SDS-polyacrylamide gel electrophoresis that the neutral proteinases from human polymorphonuclear granulocytes, the $\text{E}$lastase $\text{L}$ike $\text{P}$roteinase (ELP), and the $\text{C}$hymotrypsin $\text{L}$ike $\text{P}$roteinase (CLP), are able to digest purified human plasma factor XIII. Both sub-units, $\text{a}$ and $\text{b}$, are affected at concentrations which might locally or systemically occur under pathophysiological conditions. Higher concentrations are required for the degradation of subunit $\text{b}$. Depending on the proteinases, the concentration used and the time of incubation, numerous split products were formed. To obtain comparable effects, the concentration of CLP had to be about twice that of ELP. Aprotinin had only a slight inhibitory effect on the two leukocyte proteinases. The results presented indicate that factor XIII is degraded and inactivated by granulocytic proteinases, both subunits being altered by these proteinases. Therefore the determination of subunit $\text{b}$ may be helpful in differentiating between the proteolytic effect of thrombin which degrades only subunit $\text{a}$, and the granulocyte proteinases.     

Delayed diagnosis of optic nerve glioma: a preventable cause of visual loss

Optic nerve glioma is a rare but important cause of visual impairment during childhood. The presenting symptoms and signs usually are visual, but are commonly misinterpreted. We report 18 children with visual loss secondary to optic nerve glioma. Thirteen of these patients presented with failing vision; only 3 had a correct initial diagnosis. The errors in diagnosis resulted in many years of treatment delay with consequent further visual impairment or no improvement in vision and a possible reduced efficacy of treatment. This delay may explain some of the controversy surrounding the role of radiotherapy in the management of these tumors. The diagnosis of optic nerve glioma must be considered in any child who presents with failing vision, optic atrophy, and/or nystagmus, in whom there is no demonstrable intraocular cause.     

Health-related quality of life of children with vision impairment or blindness

The aims of the study were to describe the functional ability, health status, and health-related quality of life (HRQL) of young children with a vision impairment or blindness (VI/BL) and to examine the effect of different types of ophthalmic condition and the presence of other impairments or systemic disorders. A cross-sectional community survey of children aged 3 to 8 years with VI/BL was conducted in four areas of England using the Health Utilities Index Mark 3 system. Seventy-nine children (47 males, 32 females; mean age 6 y 2 mo [SD 1 y 6 mo]) met the selection criteria: 43% had a visual pathway condition, 38% a condition of the eye, and 19% nystagmus alone; and 61% had additional impairments/disorders. Eighty per cent had functional limitations on at least two of the following attributes: vision, hearing, speech, cognition, ambulation, dexterity, emotion, and pain. Forty-four per cent had functional limitations on four or more attributes. Children with nystagmus alone had significantly higher mean HRQL utility scores (0.80 [SD 0.26]) than children with a condition of the eye (0.45 [SD 0.33]), who, in turn, had higher scores than children with a visual pathway condition (0.05 [SD 0.33], p=0.002). Children with an isolated VI/BL had significantly higher mean scores (0.73 [SD 0.21]) than those with additional impairments/disorders (0.09 [SD 0.34], p<0.001). These findings underline the need for a broad assessment of each child with VI/BL and a multidisciplinary approach to care.     

Visual-deficit following long-term continuous light exposure

Extensive retinal degeneration without significant visual deficit has been shown to follow long-term continuous light (CL) exposure of albino rats. The present study attempted to determine if vision was affected with the CL exposure extended beyond that necessary for complete degeneration of the rod cells. Performance of a light-dark discrimination task tested visual function in albino rats after 400 1x CL exposure. Microscopic examination of all retinas assessed rod cell density. Performance decrements and retinas without rod cells appeared after 90 days CL exposure. Five animals without rod cells accurately performed the discrimination task (84–99% correct.) No rod cells were found in retinas CL exposed more than 130 days. Animals CL exposed for 130–216 days showed a progressive performance decrement with exposure. Five animals trained early in a 120–150-day CL exposure period maintained high performance levels $\text{(}\text{96.8}\text{\%)}$. Lower performance levels $\text{(}\text{75.6}\text{\%)}$ were obtained by animals trained after 120 days CL exposure. These results verify previous findings that rats could perform light-dark discriminations without rod cells. It was concluded that cells supporting visual function in the absence of rod cells were subject to functional deficits after long-term CL exposure. It was predicted that exposure to CL of sufficient intensity and duration would result in blindness. A process of generalization was proposed in which learning with intact rod cells generalized to other cell types to account for the maintained high performance levels of animals trained at the beginning of long-term CL exposure.     

Sugar derivatives of indolamines. Part IV: dissociation between the affinity of desoxyribulo-serotonin towards D and M type tryptaminergic receptors and study of its effect on platelet functions.

Desoxyribulo-serotonin shows a serotonin-like activity on both $\text{D}$ and $\text{M}$ type tryptaminergic receptors. Similarly to desoxyfructo-serotonin, its affinity is about 100 times less towards these receptors when compared to serotonin. The intrinsic activities of the two sugar derivatives for $\text{D}$ type receptors are nearly equal and very close to the initial value of serotonin. Desoxyfructo-serotonin showed a decreased intrinsic activity for $\text{M}$ type receptors with 70 % of the initial value observed for serotonin. The intrinsic activity of desoxyribulo-serotonin for these receptors is even less, showing only 40 % activity.The effect of desoxyribulo-serotonin on platelet functions is revealing : in spite of its decreased intrinsic activity towards $\text{M}$ type receptors, the ribose derivative shows unchanged or higher activities in shape-change, aggregation, inhibition of the uptake and the release of serotonin, than desoxyfructo-serotonin, confirming earlier observation, that $\text{M}$ type receptors are $\text{not}$ involved in platelet functions. It is noteworthy that desoxyribulo-serotonin is a nearly total inhibitor of the release of serotonin from platelets induced by 5,6-dihydroxytryptamine.     

Late-onset acid maltase deficiency: Biochemical studies of leukocytes

The activities of acid and neutral maltase were measured in lymphocytes, granulocytes, and platelets isolated from controls and from 5 patients with late-onset acid maltase deficiency (AMD).Lymphocytes from patients had markedly decreased activity of acid maltase and elevated $\text{neutral}\text{acid}$ ratios. In granulocytes, acid maltase was also lower than in controls, but significant activity was retained at pH $\text{4:}\text{neutral}\text{acid}$ ratios were consistently elevated. Normal platelets had low acid and high neutral maltase activities: both enzyme activities varied within wide ranges and patients could not be distinguished from controls.The variable proportion of different cell types in unfractionated leukocyte preparations may yield unreliable values when used for detection of AMD. However, lymphocytes isolated from 20 ml of blood provide a readily accessible and reliable source of tissue for accurate diagnosis.     

Benign intracranial hypertension

Benign intracranial hypertension (BIH) is characterized by an elevation of the intracranial pressure not associated with an intracranial process or hydrocephaly, and with normal cerebrospinal fluid (CSF) contents. The elevation of the intracranial pressure is isolated; therefore, diseases such as cerebral venous thrombosis or dural fistulas should not be considered as etiologies of BIH. The exact definition of BIH remains debated, and other terms such as "pseudotumor cerebri" or "idiopathic intracranial hypertension" are often used in the literature. Although we agree that BIH is usually not a so benign disease, we suggest that BIH is still the most appropriate term to describe this entity which should be classified as "secondary BIH" or "idiopathic BIH" depending on whether there are precipitating factors for the development of BIH or not. We also propose new diagnostic criteria emphasizing the need for investigations for the diagnostic of secondary and idiopathic BIH. The management of patients with BIH depends mainly on the presence and severity of ocular symptoms and signs on which the prognostic of the disease is based. Repeated lumbar punctures associated with acetazolamide and weight loss are usually efficient enough. However a surgical treatment (optic nerve sheath fenestration or lumboperitoneal shunt) is required when appropriate medical management does not prevent progressive alteration of vision (visual loss or visual field defect), or when the patients complains of severe, refractory headaches. Careful follow-up with repeated formal visual field testing may help preventing a devastating visual loss in these patients.     

Coagulation studies in Neisseria Meningitidis group a meningitis in Egypt

Serotype A. $\text{N. meningitidis}$ is the common meningeal infection encountered in Egypt. Clinically it is milder than the group C infection seen in the United States and severe hemorrhagic symptoms have not been described. Blood samples from 180 patients with positive cultures for this organism were examined using prothrombin and partial thromboplastin times, platelet count and fibrinogen levels, thrombin times, euglobulin lysis times, peripheral blood smears and three tests for abnormal fibrin monomer complexes or degradation products. Abnormalities in one or more of these last three tests were found in 153 (85%) of the patients on admission but in none of the 63 healthy Egyptian controls. These findings suggested that a low grade disseminated intravascular coagulation (DIC) was occurring. Mild evidence for consumption of coagulation factors was observed in many of the patients, but severe consumption coagulopathy was not found.