Factors affecting the total occlusion time in eyes with hyperopic anisometropic amblyopia

BACKGROUND

Amblyopia treatment by occluding the healthy eye is known to be effective during a sensitive critical period. This study aims to clarify the factors for the total occlusion time (TOT) required for the amblyopic eye to achieve a normal visual acuity (VA) level of 1.0 (0.0 logMAR equivalent). This could contribute to an efficient treatment plan for eyes with hyperopic anisometropic amblyopia.

METHODS

Subjects were 58 patients (26 boys and 32 girls; age range, 3.6-9.2, average, 5.8 ± 1.3 years) with hyperopic anisometropic amblyopia. All the subjects had initially visited and completed occlusion therapy with improved VA of 1.0 or better in the amblyopic eye at Kindai University Hospital between January 2007 and March 2017. Using the subjects' medical records, we retrospectively investigated five factors for the TOT: the age at treatment, the initial VA of the amblyopic eye, refraction of the amblyopic eye, anisometropic disparity, and the presence of microstrabismus. Patient's VA improvement at one month after treatment was also evaluated to confirm the effect of the occlusion therapy.

RESULTS

The initial VA of the amblyopic eye ranged from 0.1 to 0.9 (median, 0.4). The TOT ranged from 140 to 1795 (median, 598) hours with an average daily occlusion time of 7 hours. The initial VA of the amblyopic eye and presence of microstrabismus were the significant factors for the TOT (p < 0.01). To achieve VA of 1.0 or better, patients with an initial VA of ≤ 0.3 in the amblyopic eye required a longer TOT. Moreover, patients with concomitant microstrabismus required a 1.7-fold longer TOT compared to those without microstrabismus.

CONCLUSION

Longer daily occlusion hours and early start of the treatment will be necessary for patients with poor initial VA or microstrabismus to complete occlusion therapy within the sensitive critical period.

The Association Between Improvement of Stereoacuity and Suppression in the Treatment of Anisometropic Amblyopia

Purpose

To investigate the association between stereoacuity and suppression during occlusion therapy for patients with anisometropic amblyopia.

Design

Retrospective study.

Patients and Methods

This study included 19 patients with hyperopic anisometropic amblyopia who underwent occlusion therapy. The mean age of the patients was 5.5 ± 1.4 years. The participants were evaluated for improvement in stereoacuity and suppression before beginning occlusion therapy, when the highest amblyopic visual acuity (VA) was achieved, during tapering, at the end of occlusion therapy, and at the final visit. Stereoacuity was evaluated using the TNO test or JACO stereo test. The presence of suppression was evaluated using circle No. 1 of the Stereo Fly Test or JACO results as the optotype.

Results

Of the 19 patients, 13 (68.4%) had suppression before occlusion, eight (42.1%) when the highest VA was achieved, five (26.3%) during tapering, and none at the final visit. Of the 13 patients with suppression before occlusion, 10 (76.9%) showed further improvement in stereoacuity when suppression disappeared, and nine had foveal stereopsis of 60 arcseconds. A significant association was confirmed between foveal stereopsis and suppression when the highest VA was achieved and during the tapering period (P<0.05, Fisher's exact test).

Conclusion

Suppression was observed even when the VA in amblyopic eyes reached the highest score. By gradually decreasing the duration of occlusion, suppression was eliminated, leading to the acquisition of foveal stereopsis.

National survey of amblyopia treatment in Japan: comparison with amblyopia treatment study results of the pediatric eye disease investigator group

PURPOSE

To investigate the treatment policy for amblyopia in Japan as of 2017 through a survey of multiple facilities and to compare the findings with those obtained by the Amblyopia Treatment Study (ATS) of the Pediatric Eye Disease Investigator Group.

STUDY DESIGN

Questionnaire survey study.

SUBJECTS AND METHODS

A questionnaire was sent to 181 facilities where patients with amblyopia are being treated. The outcomes of the present survey were compared with the results of the ATS study, and the coincidence rates were evaluated.

RESULTS

The questionnaire response rate was 68.0%. The treatment plan that showed the highest agreement between the outcomes of the ATS study and the present study was whether or not treatment was to be given to patients aged 10-15 years who had received no previous treatment; 90% of the facilities answered that they would provide treatment to such patients as well. The next highest agreement was the future treatment of amblyopia with stable visual acuity in the affected eye; 82.6% of the facilities responded that they would reduce the occlusion time. On the other hand, the lowest agreement rate was the follow-up period of the refractive correction for moderate anisometropic amblyopia. The ATS showed "4 months," whereas most of the facilities in the present survey replied "3 months." The agreement rate was 10.8%.

CONCLUSION

The amblyopia treatment in Japan survey did not always agree with the research results of the ATS. Japanese ophthalmologists tend to make treatment plans for amblyopia according to their clinical experience.

Efficacies of preoperative prism adaptation test and monocular occlusion for detecting the maximum angle of deviation in intermittent exotropia

Background

The efficacies of prism adaptation test (PAT) and monocular occlusion (MO) and their optimal test durations to detect the maximum angles of deviation at near and distance in eyes with intermittent exotropia (IXT) were assessed and compared.

Methods

We retrospectively reviewed the medical records of 72 patients with IXT. All the patients had undergone the initial strabismus surgery between April 2015 and October 2018 and had been preoperatively tested by both PAT and MO performed on different days for 30 and 60 min. Near and distance deviations after 30 and 60 min of PAT and MO were compared to their baseline measurements obtained immediately after prism wear and before occlusion by alternate prism cover test. The near/distance measurements and required test duration to reveal the maximum deviation angle were also compared between PAT and MO.

Results

Compared with the baseline, the near deviation by PAT significantly increased after 30 (P < 0.05) and 60 (P < 0.01) minutes but not the distance deviation. However, the increase after 30 min was not significant. By MO, neither near nor distance deviation showed a significant difference from the baseline after 30 and 60 min. PAT showed a significantly larger near deviation than MO at 30 and 60 min, but a larger distance deviation by PAT was only observed at 30 min.

Conclusions

In patients with basic and convergence insufficiency types of IXT, a 30-minute PAT appears to be more effective than MO in revealing the maximum angle of deviation before strabismus surgery.

Effect of Sensitivity Disparity Between the Two Eyes on Pointwise Monocular Sensitivity Under Binocular Viewing in Patients With Glaucoma

PRCIS

A difference between monocular sensitivities measured with and without occlusion was observed in glaucoma. Monocular sensitivity without occlusion could have been affected differently by binocular interaction due to the sensitivity disparity between both eyes.

PURPOSE

To investigate the influence of sensitivity disparity between both eyes on visual field results under binocular viewing in glaucoma.

MATERIALS AND METHODS

Thirteen glaucoma patients tested by Humphrey Field Analyzer (HFA) and imo were reviewed retrospectively. On the basis of their HFA results, we defined the eye with a better HFA-MD as "the better eye" and the fellow eye with a worse HFA-MD as "the worse eye." Depending on the pointwise pattern deviation (PD) of both eyes, all evaluated test points were classified into 4 groups: normal PD in both eyes (N/N), normal PD in the better eye but abnormal in the worse eye (N/A), abnormal PD in the better eye but normal in the worse eye (A/N), and abnormal PD in both eyes (A/A). Using imo, which can measure sensitivity with and without occluding the nontested eye, the better eye's sensitivities with and without occlusion were compared in each group using weighted data. The weight was derived by applying the inverse probability weighting.

RESULTS

Monocular sensitivity without occlusion was higher than that with occlusion in N/N (P<0.01) and the opposite was observed in A/A (P<0.05). No significant sensitivity difference between both conditions was seen in N/A or A/N. In N/A, the points showing a higher sensitivity without occlusion decreased as the sensitivity difference between both eyes increased.

CONCLUSIONS

A difference between sensitivities measured with and without occlusion was observed in glaucoma. Owing to the sensitivity disparity between both eyes, monocular sensitivity without occlusion could have been affected differently by binocular interaction.

Influence of Test Distance on Stereoacuity in Intermittent Exotropia

AIMS

To investigate influence of test distance on stereoacuity in intermittent exotropia (X[T]) using the same test conditions for both near and far distances.

METHODS

Subjects were 38 consecutive patients with X(T). All the patients were between ages 6 and 15 years and had decimal visual acuity of 1.0 or better. Another inclusion criterion was presence of phoric condition at near and far distances. Stereoacuity was measured at a near distance of 40 cm and at a far distance of 5 m. The following test conditions were used for both test distances: separation of the two eyes using polarized glasses, and a target with a random dot pattern. All the stereograms had the same subtended angle of 2.5º, and binocular disparity of 480, 240, 120, and 60 arcsec. We used two stereogram types with crossed and uncrossed disparities.

RESULTS

Far stereoacuity of 38 subjects measured with the crossed disparity was significantly worse than near stereoacuity (P<0.05, Wilcoxon signed-ranks test), although 30 (78.9%) of the 38 subjects showed no differences in stereopsis between the near and far distances. Far stereoacuity of 38 cases measured with the uncrossed disparity was significantly worse than at near (P<0.05, Wilcoxon signed-ranks test), although 20 (52.6%) of the 38 subjects showed no differences between stereoacuity at near and far. In comparison of stereoacuity with crossed disparity and uncrossed disparity, stereoacuity with crossed disparity was significantly better than that with uncrossed disparity both at near and far (P<0.05, Wilcoxon signed-ranks test).

CONCLUSIONS

Stereoacuity in X(T) was different according to test distance when measured controlling subtended angle of stereogram at both distances. Far stereoacuity was significantly worse than near stereoacuity when measured using test targets with both crossed and uncrossed disparities. Additionally, stereoacuity measured with crossed disparity was better than that with uncrossed disparity at both distances.

[Viewing 3D stereoscopic images in children and adults with and without strabismus: multicenter study in Japan]

PURPOSE

To investigate the ability of patients with strabismus and/or amblyopia to see 3D images.

METHODS

A questionnaire survey conducted for children aged 6 to 19 years and adults aged 20 to 39 years on their experience of viewing 3D images (movies, motion attractions, television, games), asking whether they could see stereoscopically, with or without adverse effects. A retrospective investigation of ophthalmological examinations was followed.

RESULTS

Of 507 cases, 342 had had the experience of veiwing 3D images. In 212 (62%) cases of strabismus and/or amblyopia, stereopsis was lacking in 17 to 18% of the subjects for movies, in 6 to 7% for attractions, in 32% in children and 50% in adults for television and 23% in children and 17% in adults for games. Adults complained of a higher rate of adverse effects, 65% for movies and 75% for games, as compared with 34% for movies and 26% for games in children(p < 0.01). The lack of stereopsis for games and movies was higher in the subgroup of Fly (-) and convergence insufficiency (p < 0.05).

CONCLUSIONS

Since many patients with strabismus and/or amblyopia found some difficulty in stereoscopic viewing, precise examinations for stereopsis and convergence are needed to assess individual aptitude for 3D viewing.

Superior sagittal sinus dural arteriovenous fistulas treated by stent placement for an occluded sinus and transarterial embolization. A case report

We describe a case of dural arteriovenous fistulas (DAVFs) involving the superior sagittal sinus (SSS) successfully treated with stent placement for an occluded sinus and transarterial embolization. A 61-year-old man who had been treated with anticoagulation for a known SSS thrombosis presented with a sudden onset of headache. CT scan revealed an intraventricular hemorrhage and cerebral angiography revealed DAVFs involving the SSS which had severe venous congestion and sinus occlusion. We treated this case with a staged endovascular approach which consisted of stent placement for the occluded sinus and transarterial intravenous embolization resulting in complete eradication of DAVFs. Recanalization of an occluded sinus by stent placement can reduce venous congestion and transarterial intravenous embolization can obliterate dural arteriovenous shunts. This staged strategy is feasible and should be considered a first option of treatment, especially for DAVFs which presented with intracranial hemorrhage and aggressive venous hypertension.

Direct percutaneous carotid artery stenting for a patient with absence of the common carotid artery

A 54-year-old man with symptomatic internal carotid artery stenosis with absence of the common carotid artery (CCA), who had been treated with surgery and postoperative radiotherapy for tonsillar carcinoma, underwent direct percutaneous carotid artery stenting (CAS). To our knowledge, this is the first report of direct percutaneous carotid artery stenting (CAS) for a patient with absent CCA.

Influence of background complexity on visual sensitivity and binocular summation using patterns with and without noise

PURPOSE

To investigate how background complexity influences visual sensitivity and binocular summation.

METHODS

Using two noise backgrounds (noise-sparse and noise-dense) and two corresponding noise-free backgrounds with the same luminance for each noise background, monocular and binocular thresholds were measured in six visually normal subjects (average age, 27.3 ± 1.1 years). The noise-sparse and noise-dense backgrounds respectively had 312 and 936 white-light dots projected on them-the same size white-light dots (0.431° of visual angle) as those that were used for the white-spot target in the threshold measurement. The target was tested at the fovea and at 3° intervals on the 45°, 135°, 225°, and 315° meridians. A total of 25 locations were tested.

RESULTS

The monocular threshold for the noise-dense background was higher than that for its corresponding noise-free background, with significant differences seen at 15° and 18° (P < 0.01). No significant differences in the binocular threshold were seen, either between the noise-dense and its corresponding backgrounds or between the noise-sparse and its corresponding backgrounds. The binocular summation ratios for both noise backgrounds were significantly higher than the ratios for the noise-free backgrounds, and the difference increased with eccentricity, with significances seen at 15° and 18° (P < 0.01).

CONCLUSIONS

Only the monocular threshold increases with background complexity. The binocular summation increases with background complexity in the periphery. When the background becomes more complex and the monocular visual processing reaches its limit, binocular interaction functions efficiently.

Technique for shaping microcatheter tips in coil embolization of paraclinoid aneurysms using full-scale volume rendering images of 3D rotational angiography

INTRODUCTION

In coil embolization of paraclinoid aneurysms, it is sometimes difficult to introduce and stabilize microcatheter tips in the aneurysms. We report a new technique for shaping microcatheter tips in the coil embolization of paraclinoid aneurysms.

METHODS

From May 2007 to May 2008, this new technique was applied to 10 paraclinoid aneurysms undergoing coil embolization. Before coil embolization, 3D rotational angiography was performed, and volume-rendering images were reconstructed. Vinyl-coated handicraft wire was shaped 3-dimensionally to fit full-scale volume-rendering images on the monitor, from the C5 portion of the internal carotid artery to the center of the dome of the aneurysm from various angles. The microcatheter tip was then shaped with steam to fit the vinyl-coated wire. Thereafter, the microcatheter tip was introduced into the aneurysm and coil embolization was performed.

RESULTS

Microcatheter tips could be easily shaped and could be introduced smoothly into aneurysms, and were stable during coil embolization.

CONCLUSION

This technique is feasible for shaping microcatheter tips precisely for coil embolization of paraclinoid aneurysms.

Complete Cure of Superior Sagittal Sinus Dural Arteriovenous Fistulas by Transvenous Embolization through the Thrombosed Sinus in a Single Therapeutic Session. A Case Report

SUMMARY

Endovascular treatment often fails to completely eliminate dural arteriovenous fistulas (dural AVFs) involving the superior sagittal sinus (SSS). We report a successful case of dural AVF involving the SSS using transvenous embolization through the thrombosed sinus in a single therapeutic session.

Binocular Summation of Detection and Resolution Thresholds in the Central Visual Field Using Parallel-Line Targets

PURPOSE

To investigate the effect of thresholds on binocular summation for detection and resolution of parallel-line targets of different widths.

METHODS

The automatic perimeter Octopus 201 (Haag-Streit International, Köniz, Switzerland) combined with a modified haploscope device and targets consisting of parallel lines that were 10' (10' target), 2.5' (2.5' target), or 1.43' (1.43' target) of visual angle in width and apart were used to measure the thresholds for monocular-binocular detection and resolution of the targets under the same binocular fusion stimulation conditions in seven young adults with normal vision. The custom program in the automatic perimeter was used to test 27 points. Seventeen of the 27 points were located in the central 6 degrees of visual field and 10 on the horizontal meridian subtending visual angles of 8 degrees , 10 degrees , 12 degrees , 16 degrees , and 20 degrees .

RESULTS

The resolution threshold was significantly higher than the detection threshold for the 2.5' and 1.43' targets (P < 0.01 by Bonferroni/Dunn test). Furthermore, as the target width decreased to 2.5' or 1.43', the binocular summation ratio for the resolution threshold increased significantly over that for the detection threshold, with increasing distance from the fovea (P < 0.01 by Wilcoxon signed ranks test).

CONCLUSIONS

Binocular summation for detection and resolution thresholds varies as a function of the width of a parallel-line target. The difference between binocular summation ratios for detection and resolution thresholds increases with decrease in target width and increase in eccentricity from the fovea. Binocular interaction plays an important role in the task of recognizing a high-resolution target in the parafoveal area.

Intraoperative three-dimensional reconstruction of power Doppler vascular images

We have developed a simple method for reconstructing a three-dimensional (3D) image in the operating room from sequentially scanned intraoperative two-dimensional (2D) power Doppler images using a personal computer and commercially available software. During three operations, 2 for cerebral aneurysm and 1 for cerebral tumor, intracranial vessel images were digitally transferred to a personal computer by freehand scanning over the dura mater or surface of the brain with a 7.5-MHz linear probe. A series of 2D images were converted to a smaller file, and 3D image was reconstructed with volume-rendering software. It took about 15 minutes to reconstruct of the initial 3D image. In the cases of cerebral aneurysm, the vessels connected to the lesion or running nearby were easily identified on the image. In the tumor case, the anatomical relation between the vascular structures and the tumor was clear. This simple 3D reconstruction method provides spatial information about intracranial vascular structures that is useful in intraoperative surgical planning.

Properties of receptive field on binocular fusion stimulation in the central visual field

BACKGROUND

Visual information projected onto corresponding points on the right and left retinas converges on the binocular cells in the visual cortex. The aim of this study is to investigative the characteristics of the receptive field for binocular stimulation in the central visual field of normal-sighted human subjects.

METHODS

We investigated the receptive field for binocular stimulation under fusion conditions by combining the Octopus 201 with the space synoptophore. We measured binocular and monocular sensitivities while the fusion patterns were projected onto the Octopus 201 cupola, using the space synoptophore. We designed a new program to test 37 points in the central 6 degrees visual field. Six target sizes were tested: the white-spot targets of 0.054 degrees, 0.108 degrees, 0.216 degrees, 0.431 degrees, 0.862 degrees and 1.724 degrees projected diameters.

RESULTS

The threshold energy necessary for binocular stimulation was lower than that for the monocular stimulation in all subjects. This difference was more obvious on the test points that were more distant from the fovea when target sizes of 0.054 degrees and 0.108 degrees were used. The amount of binocular summation ratio was highest for target size 0.054 degrees in each stimulus area in the central 6 degrees of the visual field. When we measured binocular summation using target sizes larger than 0.108 degrees, the result was the constant summation.

CONCLUSIONS

The size of the receptive field for binocular stimulation is smaller than monocular stimulation under the same fusion condition. The amount of binocular summation varies as a function of target size.

[Effect of stimulus size on binocular summation within the binocular visual field]

PURPOSE

To study the influence of stimulus sizes on binocular summation using the modified Octopus 201 combined with a space synoptophore.

METHODS

Four normal subjects, aged 21 to 26 were tested. Using the SARGON program, we designed a new program to test 37 points in the central 6 degrees visual field. Sensitivity of the central 6 degrees visual field under monocular and binocular conditions was measured while the fusion patterns were displayed on the space synoptophore. The visual fields were measured at stimulus sizes 1, 3, and 5.

RESULTS

The visual sensitivity under binocular conditions was higher than under monocular conditions for all the stimulus sizes. Binocular summation for stimulus size 1 was present in a flat form, for stimulus size 3 in a convex form, and for stimulus size 5 in a concave form in the central 6 degrees visual field.

CONCLUSION

Binocular summation differed in stimulus size and retinal eccentricity. Binocular summation for stimulus size 3 increased in the fovea and it increased for stimulus size 5 in the peripheral area in the central 6 degrees visual field.

Vitamin E supplementation attenuates leakage of enzymes following 6 successive days of running training

The purpose of this study was to examine whether vitamin E supplementation in humans would attenuate an increase of serum enzymes as an indirect marker of muscle damage following a sudden large increase in the running distance in a 6-day running training or not. A randomized and placebo-controlled study was carried out on fourteen male runners who were supplied vitamin E (alpha-tocopherol 1200 IU x day(-1); E) or placebo (P) 4 weeks prior to (T1) and during 6 successive days of running training (48.3 +/- 5.7 km x day(-1), means +/- SD). Resting venous blood samples were obtained before maximal treadmill running, at T1, the day immediately before (T2), the next day (T3), and three weeks (T4) after the running training. Serum levels of alpha-tocopherol, lipid peroxidation products (thiobarbituric acid; TBA), creatine kinase (CK), lactate dehydrogenase (LDH), and LDH isozyme 1-5 were quantitatively analyzed. No significant difference was found in maximal oxygen uptake (VO2max) and maximal heart rates following the exhaustive exercise between the P and E group during the experiments. Vitamin E supplementation significantly increased serum alpha-tocopherol (p<0.001) and decreased TBA levels (p < 0.001) compared with pre-supplementation levels. Although serum CK and LDH activities increased significantly at T3 in either group, significantly lower CK (p < 0.05) and LDH (p < 0.001) levels were observed in the E group compared with the P group. The ratio of LDH1 to LDH2 (LDH1/LDH2) decreased significantly at T3 in either group compared with the T1 levels, since there was no significant difference in the LDH1/LDH2 between the P and E group throughout the experiments. These results indicate that vitamin E supplementation can reduce the leakage of CK and LDH following 6 successive days of endurance running. The protective effect of vitamin E against free radicals probably inhibits free-radical-induced muscle damage caused by a sudden large increase in the running distance.

Purely laparoscopic pylorus-preserving gastrectomy with extraperigastric lymphadenectomy for early gastric cancer: a case and technical report

For the purpose of prevention of postgastrectomy syndrome and a less invasive and yet curative oncological resection, a purely laparoscopic pylorus-preserving gastrectomy with extraperigastric lymphadenectomy was performed for a patient with early gastric cancer located in the middle third of the stomach. The patient's postoperative course was uneventful. During his postoperative recovery, the patient experienced very little pain and used analgesic medication only one time. This operation appeared to be oncologically adequate. As of the seventh postoperative month, the patient never experienced dumping syndrome or alkaline reflux gastritis. This procedure is technically feasible and an excellent option because of its reduced surgical invasiveness and better postoperative quality of life.

[Spinal lipoma in children: analysis of magnetic resonance image for upward displacement of medullary-conus on 44 consecutive surgical cases]

Medullary conus-untethering operation was conducted on 52 infants with spinal lipoma. Magnetic resonance (MR) image was used in order to evaluate the untethering results in 44 out of these 52 patients who could be followed-up after Osaka Medical Center & Research Institute for Maternal & Child Health was opened. Talking into account the changes in vertebral body during the growth period of infants, the authors studied the upward displacement of the conus-lipoma interface by four fractional MR sagittal image, using the vertebral body-intervertebral disc space as the baseline. Upward displacement was confirmed in 27 of 44 (61.4%). The mean, median and trimmed mean of upward displacement were 1.78 +/- 0.80, 2.0, 1.70 fractions, respectively. Sixteen (59.3%) were caudal type, 10 (37.0%) were transitional type and 1 (3.7%) was dorsal type. By type of spinal lipoma, upward displacement was observed in 16 of 23 caudal type patients (69.6%), 10 of 16 transitional type patients (62.5%) and 1 of 5 dorsal type patients (20%). While the rate of upward displacement was almost equal between the caudal and transitional type, that of dorsal type was lower. However, statistical analysis for the difference in population percentage of the three groups showed that significant difference existed only in the caudal type group.

Decrease in N-acetylaspartate without commensurate accumulation of acetate in focal cerebral ischemia in rat

N-acetylaspartate (NAA) is a plausible marker of neuronal viability which decreases in a variety of neurodestructive conditions. To elucidate the mechanism that leads to NAA decline in two different types of cerebral ischemia in rats, we simultaneously determined cortical concentrations of NAA and its hydrolytic metabolites, aspartate, and acetate by high-resolution 1H-NMR spectroscopy. NAA decreased almost linearly up to 24 h in both decapitation induced global cerebral ischemia, and in ischemic cortices of focal ischemia. Acetate was increased continuously for up to 24 h of global ischemia, while in focal cerebral ischemia it was increased transiently at 6 h. Aspartate did not show any change in global ischemia, while it was decreased in focal ischemia. Although NAA decreased similarly in the brain with global and focal ischemia, temporal changes of two NAA hydrolytic metabolites were different in each type of ischemia. The present results suggest hydrolytic degradation of NAA may be modified alternatively under each pathophysiologic condition.

[Vein of Galen aneurysmal malformation: multi-staged feeder clipping in two neonatal cases with intractable heart failure]

The authors reported the surgical experience of two cases of vein of Galen aneurysmal malformation in the newborn, whose congestive high-output cardiac failure was intractable. Along with the intensive care to clinical manifestations of the heart failure, multi-staged feeder clipping was carried out to decrease the high-flow shunt of the malformation. As stages going on, heart failure was relieved gradually and cathecolamines were weaned. Although certain retardation became apparent in both cases, they are showing satisfactory development in the long-term follow up. By the recent advancement of the embolization technique, the embolization appears to have already taken place the treatment of choice for this malformation. According to the neonatal evaluation score of Lasjaunias, the embolization would no longer be recommendation in neonates, whose general condition scored less than eight points. The authors believe, based on our two cases, that multi-staged feeder clipping is one of the effective modality of treatment in neonates of the vein of Galen aneurysmal malformation with severe multiorgan failure.

[Urodynamic studies on the untethering of spinal lipoma in the children]

We performed conus untethering on 44 children with spinal lipoma. In this retrospective study, we studied urological examinations obtained in 36 consecutive patients. Urological examinations were ultrasonography of bladder and kidney, voiding cystourethrography (VCG), and urodynamic cystometry. In those of them, 6 patients had already had urinary dysfunction at preoperative stage, but 4 patients' spinal lipoma was one complication of cloaca exstrophy and 2 patients' spinal lipoma after repairment of their myelomeningocele. In the remaining 30 cases, 18 patients (60.0%) as the group 1 did not have urinary dysfunction and abnormality in any urological examinations. Another 7 patients (23.3%) as group 2 also did not have urinary dysfunction, but abnormal vesicoureteral reflux (VUR) was found out in their VCG examination. At postoperative stage, abnormal VUR resolved or improved in all these 7 cases, but one of them showed transient urinary retention. Two patients of 18 in the group 1 had to require clean intermittent self-catheterization at postoperative stage. These observations confirmed that children with spinal lipoma were more likely to present with urological findings, and so it was imperative that a diagnosis be made and treatment be instituted as early as possible.

Combined transfrontal and endonasal endoscopic surgery of epidural abscess following frontal sinusitis. A case report

A large epidural abscess secondary to frontal sinusitis in a previously healthy 19-year-old man was successfully treated with a small eyebrow incision using combined transfrontal and endonasal endoscopic technique. The abscess was resolved with concomitant pneumatization of the paranasal sinuses. The present case illustrates the promising use of endoscopy in the merging fields of neurosurgery and otorhinolaryngology.

Identification of a receptor tyrosine kinase involved in germ cell differentiation in planarians

To investigate external signals involved in germ cell differentiation from somatic stem cells, we have tried to identify protein kinases whose expression is regulated during the process of sexualization of asexual-state planarians. It is known that in planarians germ cells differentiate from totipotent somatic stem cells called "neoblasts" during sexualization. As a first step, we have isolated twelve protein kinase genes from cDNAs of sexual-state planarians, including three non-receptor tyrosine kinases, three receptor-tyrosine kinases and three non-receptor serine/threonine kinases, and then analyzed their expression patterns during sexualization. One of them, the DjPTK1 gene, is specifically expressed in germ cells of sexual-state planarians. DjPTK1-positive cells were also detected in the mesenchymal space during the process of sexualization, and it appears that these cells migrate to the dorsal side and then differentiate into spermatogonia/spermatocytes in testis. Sequence analysis indicated that the DjPTK1 gene encodes a receptor protein tyrosine kinase belonging to the FGFR/PDGF family. These results suggest that a receptor tyrosine kinase system may be involved both at an early stage of germ cell differentiation and in a step of germ cell maturation in planarians.

Changes in brain organic osmolytes in experimental cerebral ischemia

The cell volume is regulated not only by inorganic ions, but also by organic osmolytes, such as amino acids, methylamines, and polyhydric alcohols (polyols). Using proton nuclear magnetic resonance spectroscopy (1H-NMR), we measured the tissue concentrations of amino acids (alanine, aspartate, gamma-aminobutyric acid (GABA), glutamate, glutamine, N-acetyl-aspartate (NAA), taurine), methylamines (glycerophosphorylcholine (GPC), creatine+phosphocreatine (total creatine, tCr)), and polyols (myo-inositol) in the rat brain after middle cerebral artery occlusion (incomplete focal ischemia) or after decapitation (complete global ischemia). The total osmolytes expressed as a sum of total amino acids, total methylamines, and total polyols were significantly decreased at 24 h of focal ischemia (58.7% of control value, P=0.0025) whereas they were not changed following decapitation. The water content was increased from control value of 77.9%-84.1% after focal ischemia (P<0.0001) but not after decapitation. These results suggest that the brain organic osmolytes are involved in the process of edema formation following focal cerebral ischemia. Further elucidation of the cellular mechanisms regulating these organic osmolytes in cerebral ischemia may promote greater understanding of the pathophysiology involved in the evolution of brain edema.

[Anesthetic and perioperative management of a neonatal vein of Galen malformation with multiple organ failure]

We treated a neonate in intractable cardiac failure due to a vein of Galen malformation. She manifested severe multiple organ failure. Perioperative problems are cardiac failure, respiratory failure, renal as well as hepatic dysfunction, and coagulopathy. Direct clipping of the feeding arteries improved her symptoms. Anesthetic problems encountered in this patient are massive bleeding and drastic circulatory changes while clipping the feeding arteries, increased intracranial pressure and brain ischemia, and other underlying complications; hepatic and renal dysfunction, respiratory failure and coagulopathy.

[Clinical and electroencephalographic studies in children with hemimegalencephaly]

Clinical and electroencephalographic (EEG) studies were performed in two children with hemimegalencephaly. The ages of seizure onset were 44 hours after birth in one infant and 33 days of postnatal life in the other patient. In both children, infantile spasms (IS) associated with hemihypsarrhythmia, developed at 1.5 months and 4 months, respectively. The subsequent clinical courses in these children were notable for frequent, intractable seizures. The seizures consisted of either generalized or partial seizures which originated from not only the hemimegalic hemisphere but also the contralateral one. Later, the clinical and EEG findings in one child indicated the development of Lennox-Gastaut syndrome (LGS). These findings suggested that the lesions of epileptogenesis in patients with hemimegalencephaly involved not only the pathological hemisphere, but also the contralateral hemisphere and subcortical structures. A detailed neurophysiological investigation in hemimegalencephaly could help the elucidation of the pathophysiology of intractable epilepsies, such as IS or LGS.

Serial IMP-SPECT and EEG studies in an infant with hemimegalencephaly

An 8-month-old girl of hypomelanosis of Ito associated with hemimegalencephaly had frequent seizures beginning 44 h after birth. The seizures were secondarily generalized or unilateral initially, followed by infantile spasms at about 1.5 months of age. Frequent partial seizures appeared at 4 months of age. [123I]N-Isopropyl-p-iodoamphetamine (IMP) single photon emission computed tomography (SPECT) was performed serially during an interictal period at 1, 3 and 7 months of age. At 1 and 3 months, IMP-SPECT showed a marked increase of IMP uptake in the pathological left hemisphere and electroencephalography (EEG) revealed left-sided dominant hypsarrhythmia. At 7 months of age, a reversal was seen, there being decreased uptake on SPECT in the pathological hemisphere and abundant high amplitude background activity mingled with epileptic discharges on EEG in the non-pathological hemisphere. These serial changes of IMP uptake on SPECT seemed to reflect either changes in epileptic activity or maturational changes in cerebral perfusion in hemimegalencephaly.

Evaluation of masked neurological disorders in the chronic stage after middle cerebral artery occlusion in rats--methamphetamine-induced rotation and regional glucose metabolism in basal ganglia

Neurofunctional changes in rats in the chronic stage of focal cerebral ischemia induced by left middle cerebral artery (MCA) occlusion were examined. Neurological disorders and behavioral changes were observed with or without methamphetamine administration. Metabolic changes in the basal ganglia following methamphetamine intraperitoneal injection were evaluated by [14C]deoxyglucose autoradiography 30 days after occlusion. Neurological examination revealed persistent spontaneous rotation to the lesioned side in two of 18 rats, and forelimb flexion to the lesioned side in nine of 18 rats during a 28-day observation period after occlusion. Intraperitoneal administration of methamphetamine (4 mg/kg) induced full 360 degrees rotation toward the lesion side in 14 of 17 rats. The number of rotations was inversely correlated with the size of the intact striatum on the lesion side, especially in rats with cerebral infarct located only in the striatum. Rats with extensive cortical lesion in addition to striatal lesion did not demonstrate this relationship. Deoxyglucose autoradiography in methamphetamine-untreated rats showed symmetrical local cerebral glucose utilization in the basal ganglia except for the subthalamic nucleus, striatum and sensorimotor cortex. Autoradiography in methamphetamine-treated and MCA-occluded rats showed a remarkable increase in glucose utilization in the anterior striatum, entopeduncular nucleus, substantia nigra pars reticulata, and sensorimotor cortex contralateral to the occlusion side, but not on the lesioned side. Rotational movements observed in methamphetamine-treated rats are related to lack of stimulation of the basal ganglia system on the ischemic side.(ABSTRACT TRUNCATED AT 250 WORDS)

Two-step procedure for early neonatal surgery of fetal hydrocephalus

This retrospective study analyzed the diagnosis and treatment of 36 infants with central nervous system anomalies diagnosed antenatally by ultrasonographic studies between December, 1987 and December, 1990. Magnetic resonance imaging of the fetuses without maternal or fetal sedation/anesthesia was very useful, as the fetal ventricular system was depicted clearly. Twenty-three infants with hydrocephalus underwent early postnatal surgical emplacement of a miniature Ommaya's reservoir. Continuous cerebrospinal fluid aspiration was combined with intracranial pressure monitoring. Observation of the ventricular size used ultrasonography through the anterior fontanelle. This technique controlled the intracranial pressure during the early neonatal period without serious complications. A ventriculoperitoneal shunt was emplaced 1 month later as the second, more permanent treatment. This two-step procedure achieves brain reconstitution and prevents irreversible neurological damages. Clinical and radiographic findings are presented to illustrate the effectiveness of this approach.

[Perinatal neurosurgical care for one fetal hydrocephalus on twin gestation]

Twin gestations are responsible for a disproportionate amount of perinatal mortality and morbidity. Such gestations may impose greater demands on maternal and child physiologic systems than singleton pregnancies. The most common antenatal complications were preterm labor. The clinical record of myelomeningocele infant presenting with overt hydrocephalus in utero at 27 weeks of twin gestation and operated miniature Ommaya's reservoir placement early after birth and intentional delayed back closure for myelomeningocele was reported. Although perinatal neurosurgical care for one fetal hydrocephalus on twin gestation is clearly advantageous, it alone is relatively ineffective in reducing the incidence of the complication, preterm labor.

Changes in somatosensory circuits after subcortical infarct in rats

We compared the functional and anatomical alterations of somatosensory circuits in the acute (1-3 days after infarct) and chronic (3 months after infarct) stage after subcortical striatal infarct in Wistar rats. Occlusion of the left middle cerebral artery produced subcortical striatal infarct in approximately 69% of the rats. The others developed cortical infarct. The function of the somatosensory circuits was evaluated by [14C]2-deoxyglucose autoradiography during physiological stimulation of the right vibrissae and face. In rats with subcortical infarct, the areas activated by sensory stimulation of the right vibrissae and face, applied 1 and 3 days after occlusion, were reduced compared to sham-operated controls (P < 0.05). In the chronic stage of subcortical infarct, the areas of metabolic activation of the left anterior vibrissal and facial sensory area were increased compared to rats with acute subcortical infarct (P < 0.05). To evaluate the anatomical changes in the somatosensory pathway, at 1 day and 3 months after occlusion, we injected wheat germ agglutinin-horseradish peroxidase solution as an axonal transport substance bilaterally into the anterior vibrissal and facial sensory area. Tract tracing studies in both the acute and chronic stage of subcortical infarct showed a reduction in the peroxidase-positive area in the left thalamus compared to the control hemispheres (P < 0.01). The functional disturbance and recovery of the somatosensory circuits after subcortical infarct are discussed.

[Extremely low birth-weight infant with hydrocephalus; management of hydrocephalus using a miniature Ommaya's reservoir]

Use of the miniature Ommaya's reservoir in the treatment of extremely low birth-infant (under 1,000 mg) with hydrocephalus was studied in a series of five patients. The reservoir has a small-caliber with a 3 cm ventricular catheter. For these infants, this miniature Ommaya's reservoir is extremely useful for protection of the cortical mantle until a definitive procedure can be carried out after increase of body weight. The clinical course in five cases are summarized.

Functional impairment due to white matter ischemia after middle cerebral artery occlusion in cats

We recorded regional cerebral blood flow, somatosensory evoked potentials, and auditory evoked potentials in the thalamic relay nuclei (ventral posterior lateral nucleus and medial geniculate body) and in the somatosensory and auditory cortices during and after 1 hour of transient left middle cerebral artery occlusion in nine cats. Regional cerebral blood flow was also measured in the thalamocortical tracts of five of these cats. Additionally, the integrity of thalamocortical connections was tested by retrograde labeling of the thalamic nuclei with horseradish peroxidase in eight cats (three of which experienced no ischemia). Regional cerebral blood flow was severely reduced during middle cerebral artery occlusion in the left primary auditory cortex (8.5 ml/100 g/min) and in white matter pathways (6.4-7.6 ml/100 g/min). In contrast, regional cerebral blood flow did not change significantly in the somatosensory cortex or in either thalamic nucleus. Evoked potentials were abolished in both cortices but remained unchanged in the thalamic nuclei. Cortical somatosensory evoked potentials disappeared 5-8 minutes later than auditory evoked potentials. Recirculation after 1 hour of ischemia resulted in rapid and almost complete recovery (94%) of somatosensory evoked potentials and little recovery (18.4%) of auditory evoked potentials. We conclude that in the auditory pathway both cortical and fiber tract ischemia are (perhaps synergistically) responsible for dysfunction, while in the somatosensory cortex evoked potentials are abolished due to white matter ischemia. The delayed disappearance and better recovery of somatosensory than of auditory evoked potentials indicate that ischemic tolerance is higher in fiber tracts than in cortex.

Ischemic flow threshold for extracellular glutamate increase in cat cortex

Extracellular glutamate (Glu), cerebral blood flow (CBF), and auditory-evoked potentials (AEPs) were measured concurrently using microdialysis and hydrogen clearance in the auditory cortex of anesthetized cats during global ischemia of various severities. A threshold-type relationship was observed between extracellular Glu and CBF: Glu increased at CBF levels below about 20 ml/100 g/min. The Glu increase was related to the impairment of AEPs. The results suggest that Glu neurotoxicity is an important factor for ischemic neuronal injury even in penumbra.

Deafferentation versus cortical ischemia in a rabbit model of middle cerebral artery occlusion

A two-site middle cerebral artery occlusion model in rabbits was developed. Platinum electrodes served for simultaneous recordings of regional cerebral blood flow, auditory evoked potentials, and electroencephalogram in the left and right auditory cortex and in the left medial geniculate body. Auditory evoked potentials and regional cerebral blood flow were also recorded in the subcortical white matter, and regional cerebral blood flow was recorded in the internal capsule. Distal segment occlusion of the middle cerebral artery caused severe cortical ischemia in four of 11 rabbits (Group I), accompanied by abolition of the auditory evoked potential in the left auditory cortex and white matter and severe reduction of the left electrocorticogram. Deep subcortical regions were affected either little or not at all. In the remaining seven rabbits (Group II) with only mild disturbance of cortical perfusion after distal middle cerebral artery occlusion, additional clamping of the proximal middle cerebral artery stem reduced thalamocortical tract blood flow and abolished cortical auditory evoked potentials. Spontaneous electrocorticogram was less affected in Group II than in Group I; thalamic regional cerebral blood flow and auditory evoked potentials were not altered. Histologically, ischemic lesions predominated in the cortex of Group I and in the subcortical structures of Group II rabbits. While correlated reductions in regional cerebral blood flow and auditory evoked potentials indicate effective cortical ischemia, the impairment of auditory evoked potentials in Group II rabbits must be due to cortical deafferentation by ischemia in the afferent tract. This model permits the investigation of the effects of predominantly cortical or subcortical ischemia in one functional system.

[Cardiac myxoma metastatic to the brain]

A case of cardiac myxoma presenting as metastatic brain tumor are reported. The patient was a 44-year-old man. One year prior to this admission, he had suffered stroke, which was characterized by right hemiparesis and dysarthria. The computed tomographic (= CT) scan of the head at that time showed a low density on the left basal ganglia and the echocardiogram suggested a left atrial myxoma. At surgery, a polypoid myxoma attached to the atrial septum was totally removed. Right hemiparesis was improved and the patient was discharged. A few months later, the patient was evaluated for multiple cutaneous masses and diagnosed by biopsy as metastatic myxoma. The patient's condition remained unchanged until this admission. In March 1985, the patient had a tonic-clonic convulsion marching from right hand and developed right hemiplegia with drowsy. An echocardiogram failed to reveal recurrence of the cardiac myxoma. A CT scan revealed a 5-cm, relatively circumscribed, low density mass in the left fronto-parietal lobe, ring mottled enhancement after contrast administration and more enhancement in the delayed scanning of 45 min. Craniotomy showed a tender, friable tumor with a yellowish cyst fluid, but apparently not invading the brain parenchyma. After complete excision of the mass, there was rapid lessing in the hemiplegia and improvement in the level of consciousness. A contrast-enhancement CT scan performed 2 weeks after craniotomy revealed no evidence of residual tumor. Pathohistological examination showed spindle-shaped and stellate cells which formed clusters and contained large amounts of acid polysaccharides as demonstrated by the alcian blue method.(ABSTRACT TRUNCATED AT 250 WORDS)

Biphasic occurrence of delayed ischemia after early aneurysm surgery. Case report

An unusual case of delayed ischemia following rupture of an aneurysm of the left internal carotid artery is reported. Symptoms occurred twice after clipping the aneurysm and removing most of the subarachnoid blood on the left side the day after subarachnoid hemorrhage (SAH). Initial ischemia due to vasospasm occurred on the left side of the brain on the 8th day after SAH and responded favorably to induced hypervolemia. After complete recovery, a second episode due to vasospasm occurred on the 16th day after SAH on the right side of the brain from which the subarachnoid blood had not been removed. This caused a massive lesion and permanent severe neurological deficits. This case suggests that removal of subarachnoid blood may affect the severity and time course of vasospasm, and emphasizes the necessity of extensive removal of subarachnoid blood for prevention of severe delayed ischemic symptoms.

Cerebellar infarction with obstructive hydrocephalus

The authors review 15 patients with acute cerebellar infarction accompanied by obstructive hydrocephalus. These patients were among 1700 consecutive patients with acute cerebrovascular disease who were examined by angiography and also, except for the initial 320 cases. by computerized tomography (CT) scan. The CT scans were helpful in diagnosis and management of the patients. It demonstrated cerebellar mass lesions as being low density, isodense, or high density, according to the amount of hemorrhage into the infarcted area. Such cerebellar mass lesions caused acute compression of the posterior fossa. The clinical picture was determined mainly by the extent of the initially infarcted area in the vertebrobasilar territory and the speed of enlargement of the subsequently developing cerebellar mass lesion. Suboccipital decompressive surgery was performed in 10 patients and was generally beneficial. The postoperative prognosis depended mainly on the presence or absence of coexisting brain-stem infarction. Five patients who were managed conservatively died during the acute stage. Prompt and correct diagnosis of this illness is required to ensure adequate therapy.