Analyses of shape of eyes and structure of optic nerves in eyes with tilted disc syndrome by swept-source optical coherence tomography and three-dimensional magnetic resonance imaging

PURPOSE

To evaluate the deeper structures of the optic nerve and to analyze the shape of eyes with tilted disc syndrome (TDS) by swept-source optical coherence tomography (OCT) and three-dimensional magnetic resonance imaging (3D MRI).

METHODS

The medical records of 54 eyes of 36 patients with TDS were reviewed. The patients with TDS and high myopia were analyzed separately from those without high myopia. All the eyes were examined with a swept-source OCT, and 22 of the eyes were examined by 3D MRI.

RESULTS

A total of 38 eyes of 29 patients were highly myopic and 16 eyes of 15 patients were not highly myopic. The representative OCT findings of the optic disc were: a sloping of the lamina cribrosa posteriorly from the upper part to the lower part, a protrusion of the upper edge of Bruch's membrane, and choroid. The distance and the depth of the most protruded point from the fovea were significantly greater in the eyes with non-highly myopic TDS than those with highly myopic TDS. In the 3D MRI, the lower part of the posterior segment was protruded outward, and the optic nerves attached at the upper nasal edge of the protrusion.

CONCLUSIONS

The abnormalities detected by swept-source OCT and 3D MRI analyses indicate the possibility that the essential pathology of TDS is a deformity of the inferior globe below the optic nerve, and the positional relation between the fovea and the inferior protrusion determines the degree of myopia.

Characteristics of intrachoroidal cavitation located temporal to optic disc in highly myopic eyes

PURPOSE

To investigate the anatomic characteristics of eyes with pathological myopia and peripapillary intrachoroidal cavitation (ICC) located temporal to the optic disc.

METHODS

A total of 125 with pathologic myopia were scanned with swept-source optical coherence tomography (OCT). Temporal ICC was defined as ICC located temporal to the optic disc seen in horizontal OCT section through the optic disc center. Definition of pathologic myopia was refractive error >8.00 diopters (D) or an axial length >26.5 mm.

RESULTS

In all, 17 eyes of 16 patients had temporal ICC. All of the eyes had temporal or temporally wider annular conus. The ICC was observed temporal to the optic disc in 15 of 17 eyes, and 2 of the remaining eyes also had inferior ICC. Even in the two eyes with both temporal and inferior ICC, the temporal ICC was much wider than the inferior ICC. Inner retinal defect at the border of conus and temporal ICC was detected in two eyes. The temporal ICC was extensive in the posterior fundus with the average width of 1467.8 ± 1328.1 μm (range; 442-6200 μm) in a horizontal section. In two eyes, the temporal ICC extended beyond the central fovea.

CONCLUSIONS

Peripapillary ICC can develop temporal to the optic disc without involving the area inferior to optic disc in highly myopic eyes. Temporal ICC appeared much wider than inferior ICC, which is usually restricted to the area around the optic disc. The possible reasons why ICC develops in temporal to the optic disc are presented.

Progression from macular retinoschisis to retinal detachment in highly myopic eyes is associated with outer lamellar hole formation

Aims:

To investigate the morphological changes that occur during the development of an early retinal detachment (RD) from a myopic macular retinoschisis (MRS) by optical coherence tomography (OCT).

Methods:

The OCT images of five eyes of five consecutive patients with myopic MRS who developed an RD during the follow-up period were studied.

Results:

The progression from MRS to early RDs went through four stages. In stage 1, OCT images appeared to show a focal irregularity of the thickness of external retina. In stage 2, an outer lamellar hole developed within the thickened area and a small RD developed. In stage 3, the column-like structures overlying the hole seemed to be separated horizontally, and the outer lamellar hole appeared to be larger vertically. In stage 4, the upper edge of the external retina was further elevated and attached to the upper part of the retinoschisis layer accompanied by further enlargement of the RD.

Conclusions:

This longitudinal study showed that the progression from myopic MRS to RD passes through four stages, and the formation of an outer lamellar hole predisposes the retina to a RD. These OCT findings might be useful for considering the surgical indication for eyes with a myopic MRS.

Idiopathic nodular glomerulosclerosis: three Japanese cases and review of the literature

Idiopathic nodular glomerulosclerosis (ING) is characterized as diffuse nodular glomerulosclerotic lesions, closely resembling Kimmelstiel-Wilson lesions without diabetic mellitus. We report here three Japanese cases of ING and discuss the previous reports. The patients were 75-, 48- and 84-year-old males with a history of long-term hypertension. Laboratory examination revealed moderate proteinuria and mild renal dysfunction. Diabetes mellitus was excluded by repeated clinical and laboratory investigations. Renal histology revealed nodular glomerulosclerosis, and both afferent and efferent arteriolosclerosis in all patients. In electron microscopy, the glomerular basement membrane was markedly thick in all patients. A low-protein diet and potent anti-hypertensive treatment using angiotensin-converting enzyme inhibitors were initiated in all patients and urinary protein excretion significantly reduced without the progression of renal dysfunction. We reviewed 42 previously reported cases and our three cases. The analysis revealed that common clinical features of ING are being male (82.2%) of relatively advanced age (mean age 61.3 years), with hypertension (82.2%), mild renal dysfunction (mean serum creatinine 2.9 mg/dl) and moderate urinary protein excretion (mean 4.05 g/day). Common histopathological findings of ING are nodular glomerulosclerosis (100%), arterio-arteriolosclerosis (91.2 and 89.7%) and glomerular basement membrane thickening (85.7%). In conclusion, ING is one of the phenotypes of arteriosclerotic renal disease without diabetes mellitus. Severe arterio-arteriolosclerosis may contribute to the progression to glomerular nodular formation in ING. The combination of renin-angiotensin system inhibition and a low protein diet can be beneficial for the reduction of urinary protein excretion.

Cytoplasmic antineutrophil cytoplasmic antibody positive pauci-immune glomerulonephritis associated with infectious endocarditis

Renal deterioration often occurs in cases of infectious endocarditis (IE), but, IE- associated nephritis with rapidly progressive glomerulonephritis (RPGN) is rare. Patients with severe infection (e.g., IE) sometimes show positivity for cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA). Therefore, diagnosis and treatment are very difficult in cases of RPGN with IE and positivity for C-ANCA. Such cases are rare, only 12 have been reported in the English literature. Herein, we describe the case of a 50-year-old man who presented with RPGN with IE and tested positively for C-ANCA. He was referred to our hospital because of leg edema, purpura and renal dysfunction. Laboratory tests revealed serum creatinine elevation and positivity for C-ANCA and proteinase 3-specific (PR3)-ANCA. RPGN and acute renal failure were diagnosed. Hemodialysis and steroid therapy were started. Streptococcus oralis was isolated by blood culture. Transthoracic echocardiography revealed grade III mitral valve insufficiency with two vegetations. Therefore, IE was diagnosed. The steroid therapy was stopped, and antibiotic therapy was begun. Because there was no improvement, surgical therapy was performed. The operation was successful, but the patient died of brain hemorrhage. Our experience in this case indicates C/PR3-ANCA positive RPGN must be ruled out in patients with infectious disease, particularly IE, together with renal symptoms, and renal biopsy should be performed.

Peripapillary crescent enlargement in highly myopic eyes evaluated by fluorescein and indocyanine green angiography

AIMS

To evaluate angiographic features of myopic crescents using fluorescein angiography (FA) and indocyanine green angiography (IA).

METHODS

FA and IA angiograms of 88 highly myopic eyes (47 consecutive patients) were reviewed. The follow up period ranged from 5-28 years.

RESULTS

FA revealed two zones of the myopic crescent: a consistently hypofluorescent inner zone and an outer zone with delayed choroidal filling. IA revealed dislocation of the Zinn-Haller ring to the border between the two zones. Myopic crescent enlargement occurred in 68.1%. Only the outer zone increased significantly in most of the eyes with enlarged crescents.

CONCLUSIONS

The inner zone might develop as a result of mechanical stretching, and the outer zone might be the result a secondary circulatory disturbance and mechanical stretching.

Patchy atrophy and lacquer cracks predispose to the development of choroidal neovascularisation in pathological myopia

AIMS

To determine the incidence and predisposing findings for choroidal neovascularisation (CNV) in a large series of highly myopic patients.

METHODS

The medical records of 218 consecutive patients (325 eyes) with myopic fundus changes in the macula were reviewed. The incidence of CNV during a follow up of at least 3 years of highly myopic patients and identification of predisposing findings for the development of myopic CNV were examined.

RESULTS

Among 325 highly myopic eyes examined, 33 eyes (10.2%) developed myopic CNV. The incidence was higher (34.8%) among the fellow eyes of patients with pre-existing CNV than among eyes of patients without pre-existing CNV (6.1%). CNV developed in 3.7% with diffuse chorioretinal atrophy, in 20.0% with patchy atrophy, and in 29.4% with lacquer cracks.

CONCLUSION

Approximately one in 10 highly myopic eyes developed myopic CNV in average 130.2 months. Patchy atrophy and lacquer cracks were shown to be important predisposing findings for CNV development.

Visual deprivation stimulates the exchange of the fibrous sclera into the cartilaginous sclera in chicks

Form deprivation myopia in chicks is a widely accepted model to study visually-regulated postnatal ocular growth. The chick sclera has a cartilaginous layer as well as the fibrous layer found in mammals. It appears that a dynamic relationship exists between these two layers during visual deprivation-induced growth. The changes in the fibrous sclera of myopic eyes, however, have not been previously described. This investigation is focused on the comparative morphological analyses of the cartilaginous and fibrous scleral changes in myopic chick eyes. The fibrous scleral changes in the posterior segment of myopic eyes were examined in detail using light and electron microscopy, and the expression of growth factors was analysed by immunohistochemistry. In the posterior segment of myopic eyes the border between the cartilaginous and fibrous layers was indistinct because of collagen bundles of the fibrous sclera that spread into the cartilaginous sclera, whereas in control eyes the distinction was clear. Various types of transitional cells, from fibroblast-like mesenchymal cells to chondrocytes, were found in the border between the cartilaginous and fibrous layers. Collagen fibrillar diameters of the fibrous sclera in the posterior segment of myopic eyes were smaller than in control, whereas those in the equatorial segment were almost the same in myopic and control eyes although the distribution of sizes was obviously different. Thus, changes in the fibrous sclera in myopic eyes of chicks seem to be similar to scleral changes in myopic eyes of mammals. The cells in the posterior sclera of myopic eyes were more intensely immunostained for TGF-beta and IGF-II than control, whereas no immunoreaction of TGF-alpha could be detected in either control or myopic eyes. These results suggest that the structural characteristics of the posterior sclera are different from those of the anterior and equatorial segments. Undifferentiated mesenchymal cells might be concentrically distributed exclusively in the innermost layer of posterior fibrous sclera. TGF-beta and IGF-II might influence cell growth, differentiation, and migration in the exaggerated scleral growth accompanying myopia.

The quality of life in patients with pathologic myopia

PURPOSE

To evaluate the functional status in daily life and the quality of life (QOL) of pathologic myopia patients.

METHODS

A cross-sectional study was conducted using data of consecutive pathologic myopia patients (n = 200) and control subjects (n = 144). The influence of the disease on the daily life and the QOL of patients were evaluated using a self-rated questionnaire. The questionnaire covered the full range of daily life activity, including daily tasks depending on visual acuity, social and emotional handicaps, and cognition of disease, and the QOL of pathologic myopia patients.

RESULTS

The functional status in daily life and the QOL of patients were reduced compared with control subjects. The influence of pathologic myopia on a patient's daily life was primarily the result of three major factors, handicap, disability, and support. All three factors correlated with the QOL, the degree of handicap having the strongest correlation.

CONCLUSION

The functional status in daily life and the QOL of pathologic myopia patients were reduced; this decline in QOL was attributed to handicap and disability caused by the ocular disease.

Blue light-induced apoptosis in cultured retinal pigment epithelium cells of the rat

BACKGROUND

We previously demonstrated that phagosome-free retinal pigment epithelium (RPE) cells in culture can be damaged directly by blue light (wavelength 440+/-10 nm) as observed by electron microscope. A low intensity (1.0 mW/cm2) of light induced only swelling of mitochondria, while a high intensity (4.0 mW/cm2) induced necrosis in the RPE. The aim of the present study was to investigate what intensity of blue light could induce apoptosis in cultured phagosome-free RPE.

METHODS

Primary cultured RPE cells, harvested from Long-Evans rats, that contained no phagosomes were exposed to a cool blue light (wavelength 440+/-10 nm). After exposure, transmission electron microscopy (TEM) and TdT-mediated dUTP nick-end labeling (TUNEL) staining were used to detect apoptosis in the RPE cells. To assess the relationship of oxidation to apoptosis by blue light, we added N-acetylcysteine (NAC) as a free radical scavenger and investigated its inhibitory effect on apoptosis.

RESULTS

In RPE cells exposed to blue light of 2.7 mW/cm2 for 24 h, apoptotic bodies were found by TEM. In RPE cells exposed to blue light of 2.0 mW/cm2 for 60 h, apoptotic bodies, nuclear condensation and nuclear segmentation were observed by TEM and some RPE cells showed positive TUNEL staining. When 30 mM of NAC was added, TUNEL staining was negative.

CONCLUSION

Our findings demonstrate that apoptotic cell death is induced by blue light exposure in cultured RPE cells in vitro. The findings of our previous experiments and those of the present study suggest that a higher intensity of blue light could induce necrosis, and moderately intense blue light could induce non-necrotic cell death or apoptosis, in RPE cells. Furthermore, it is suggested that blue light caused cell death by a free-radical-associated mechanism.

Clinical course of newly developed or progressive patchy chorioretinal atrophy in pathological myopia

Regional chorioretinal atrophy in the posterior fundus (patchy chorioretinal atrophy) in pathological myopia impairs vision severely when it covers the macula. The aim of this study was to assess the course of development and progression of patchy chorioretinal atrophy in pathological myopia. The location and progression of patchy chorioretinal atrophy that was either newly developed or had progressed during the follow-up period (mean 5.25 years) were analyzed. A total of 41 lesions of patchy atrophy were newly developed in 30 eyes of 25 patients. These lesions were more likely to occur in marginal regions of a posterior staphyloma but frequency per unit area was highest in the macula. There were 138 lesions of patchy chorioretinal atrophy that progressed in 75 eyes of 53 patients. Sixty percent of the lesions of patchy chorioretinal atrophy in marginal regions of a posterior staphyloma spread toward the center. Seventy percent of the lesions of patchy chorioretinal atrophy in the macula spread in all directions. Fluorescein angiography of newly developed patchy chorioretinal atrophy showed hyperfluorescence in 50% and hypofluorescence in 27%. Fluorescein angiography of progressive lesions of patchy chorioretinal atrophy showed hypofluorescence in 69%. Fluorescein angiography of some progressive areas of patchy chorioretinal atrophy, which showed a change from hyperfluorescence to hypofluorescence within several years, suggested that damage to the retinal pigment epithelium preceded the progression of the patchy chorioretinal atrophy. In conclusion, the patchy chorioretinal atrophy is most likely to occur in the macula and to enlarge in all directions. And it is suggested that the patchy chorioretinal atrophy which shows hyperfluorescence by fluorescein angiography should be kept under observation because our data suggest that this finding indicates progression in the future.

[Peripapillary fluorescein angiographic findings in non-glaucomatous eyes]

PURPOSE

In fluorescein angiography (FAG), glaucomatous eyes show a zone of no fluorescence around the disc and hyperfluorescence indicating serum diffusion at the margin of the zone, which play some role in glaucomatous optic nerve damage. But detailed FAG findings have not been reported in non-glaucomatous eyes. We conducted a study to investigate whether peripapillary FAG findings in glaucomatous eyes were specific to glaucoma or not.

MATERIALS AND METHODS

46 eyes of 46 subjects were selected by some reservations from all the non-glaucomatous patients undergoing FAG in 1996. We studied FAG films and measured the zone of no fluorescence adjacent to the disc (non-fluorescent zone).

RESULT

44 eyes (95.6%) showed a non-fluorescent zone. The non-fluorescent zone was clearly wider in temporal sectors than nasal sectors, and its width was related to the refraction. There were two types of non-fluorescent zone, one showing hyperfluorescence from the outer boundary of the zone in the late phase, and the other showing hyperfluorescence from the disc margin. The width of the non-fluorescent zone in the former type was wider than in the latter type. These results are similar to the findings in glaucomatous eyes.

CONCLUSION

These findings suggest that not only glaucomatous eyes but also non-glaucomatous eyes have a variety of histological structures and serum diffusion around the disc.

Retinoic acid increases in the retina of the chick with form deprivation myopia

We previously reported that expression of retinoic acid receptor beta increases in the sclera of the 2-week-old chick with form deprivation myopia (FDM) and that all-trans-retinoic acid (t-RA) influences proliferation and differentiation of scleral cells. The purpose of this study was to quantify t-RA in the retina of the chick with FDM and to investigate the role of t-RA in FDM in the chick. FDM was induced in 2-day-old chicks by placement of a translucent plastic goggle over one eye, with the contralateral eye used as a control. After 5 days, the chicks were sacrificed. t-RA was extracted from neural retina and served for high-performance liquid chromatography analysis. 3H-t-RA was used for normalization. Pieces of the retinae from 5 eyes served as one sample. As a result, t-RA was 09.60 +/- 0.86 ng/eye (0.387 +/- 0.056 ng/mg protein) in the myopic retina was significantly higher than that in the control (p < 0.05, n = 7). These results demonstrate that t-RA increases in the retina within 5 days after visual deprivation. This finding suggests that t-RA may play a role in the metabolic changes in FDM.

Case report: indocyanine green dye leakage from retinal artery in branch retinal vein occlusion

BACKGROUND

Little is known about retinal vascular lesions underlying hemorrhage in the acute phase of branch retinal vein occlusion (BRVO).

CASE

A 64-year-old woman presented with a decrease in visual acuity of ten-day duration in her left eye.

OBSERVATIONS

At the initial examination, her left fundus showed the typical appearance of BRVO, including retinal bleeding and soft exudates in the lower half of the fundus, after the arteriovenous crossing. Fluorescein angiography showed no detail in the retinal vessels, which were occluded by retinal bleeding. However, in the early phase of indocyanine green (ICG) angiography, ICG dye leaked from the retinal artery at a point proximal to the first bifurcation. In the late phase of ICG angiography, the dye pooled along the retinal artery in a fusiform fashion. One year after laser photocoagulation was performed in the area of the BRVO, ICG dye leakage from the retinal artery had completely disappeared.

CONCLUSIONS

These findings suggest that the changes in the retina detected by ICG angiography may have been associated with the onset of BRVO. In patients with acute BRVO, ICG angiography may be used to evaluate retinal arterial lesions covered by hemorrhage and provide useful information.

Nitric oxide synthase expression in ischemic rat retinas

PURPOSE

To investigate the expression of nitric oxide synthase (NOS) in the ischemic retina.

METHODS

Retinal ischemia was induced in rats by bilateral common carotid artery occlusion (BCCAO) for various lengths of time. Using the retina after BCCAO, expression of neuronal NOS (nNOS) and inducible NOS (iNOS) and identification of their positive cells were studied by histological and immunohistochemical examinations.

RESULTS

Histological examinations revealed significant reduction in the thickness of the inner plexiform layer and the outer plexiform layer of the retina. Expression of nNOS was detected in retinal ganglion cells, amacrine cells, and Müller cells after BCCAO. The expression of nNOS and iNOS detected in Müller cells became stronger and persisted long after BCCAO.

CONCLUSIONS

In the ischemic retina, Müller cells and retinal ganglion cells expressed nNOS and iNOS. These phenomena may be involved in the ischemic damage to the retina.

Detection of a rectocele-like prolapse in the colonic J-pouch using pouchography: cause or effect of evacuation difficulties?

The functional outcome after a low anterior resection for rectal cancer is improved by a colonic J-pouch reconstruction. One functional problem with J-pouches is difficulty in evacuation, which is more common with large reconstructions. Since rectoceles are common findings on defecography in patients with evacuation difficulties, we proposed that a rectocele-like prolapse may be thus found in patients with large J-pouches. Pouchography was used to identify a rectocele-like prolapse (RP) in 26 patients with a 10-cm J-pouch (10-J group) and 27 patients with a 5-cm J-pouch (5-J group). Pouchography was performed at 3 months, 1 year, and 2 years after surgery. Functional assessments were performed 1 year postoperatively. Clinical function was evaluated using a questionnaire. The evacuation function was evaluated by the balloon expulsion and saline evacuation test. No patients had an RP at 3 months or 1 year after surgery. An RP was significantly more common in the 10-J group than in the 5-J group at 2 years after surgery (P = 0.0374). An evacuation difficulty was significantly more common in the 10-J group than in the 5-J group. The evacuation function in the 10-J group was also significantly inferior to that in the 5-J group. An RP appearing 2 years after surgery is more common in patients with evacuation difficulties and large colonic J-pouch reconstructions.

Spontaneous involution of a large retinal arterial macroaneurysm

BACKGROUND

Acquired retinal macroaneurysms are round dilatations of retinal arterioles that occur in the posterior fundus. They tend to rupture before they grow large and cause a visual decrease. The average diameter of macroaneurysms in the previous reports is 281 micrometer.

METHODS

A 63-year-old man complained of a sudden decrease of visual acuity in the left eye. Fundus examination of his left eye revealed a large protruded mass, 2 disc diameters in size, at the first bifurcation of the inferotemporal retinal artery. Preretinal vitreous bleeding and serous retinal detachment were observed around the lesion. Indocyanine green (ICG) angiography showed this mass to be continuous with the inferotemporal retinal artery and ICG dye leaked from the retinal artery into the lumen of the mass, with pulsation.

RESULTS

Six months later, the large macroaneurysm underwent spontaneous involution.

CONCLUSION

As shown in this patient, retinal macroaneurysms may grow extremely large. ICG angiography was useful to diagnose this large retinal arterial macroaneurysm.

Disturbance of electrolyte balance in vitreous of chicks with form-deprivation myopia

PURPOSE

To investigate the changes in the electrolyte and protein concentrations in the vitreous of 3-week-old chicks with form-deprivation myopia (FDM).

METHODS

FDM was induced in 2-day-old male white leghorn chicks by covering the left eye with a translucent plastic goggle and leaving the right eye uncovered to serve as control. After 19 days the animals were euthanized, and the axial dimensions of the eyes were measured with a caliper in an unfixed condition. The liquid vitreous and aqueous humor were removed by paracentesis, and blood was collected from the jugular vein. Sodium, potassium, and chloride concentrations were determined using ion-selective electrodes. Calcium and phosphate concentrations were determined by colorimetric assays using orthocresol phthalein complexone and bacterial xanthine oxidase, respectively.

RESULTS

The concentrations of potassium and phosphate were decreased, whereas chloride concentration was increased in the vitreous of the FDM eyes (P < .01). Sodium and calcium concentrations were similar to those in the control eyes. No significant changes in the concentration of electrolytes were observed in the aqueous humor. No significant differences were found in the protein concentrations in the liquid vitreous, gel vitreous, and aqueous humor.

CONCLUSIONS

Form-deprivation induced a significant increase of the volume of the liquid vitreous in the eye of the FDM chick. The increased liquid vitreous of the myopic eye was accompanied by an alteration of the electrolyte balance, by a mechanism that has not yet been clarified.

Horizontal inclination of the longitudinal axis of the colonic J-pouch: defining causes of evacuation difficulty

PURPOSE

Functional outcome after low anterior resection for rectal cancer is improved by the construction of a colonic J-pouch. One disadvantage of this type of reconstruction is evacuation difficulty, which has been associated with large pouches. The purpose of this study was to elucidate the causes of evacuation difficulty in large pouches using pouchography.

METHODS

The angle between the longitudinal axis of the pouch and the horizontal line (pouch-horizontal angle) on lateral pouchography was determined in 26 patients with 10-cm J-pouch reconstructions (10-J group) and 27 patients with 5-cm J-pouch reconstructions (5-J group). Measurement were made at three months, one year, and two years after surgery. Clinical function was evaluated using a questionnaire one year postoperatively.

RESULTS

The pouch-horizontal angle in the 10-J group was significantly smaller than that in the 5-J group at all three time points. In both groups the pouch-horizontal angle at one year was significantly smaller than that at three months. There were no significant differences between the pouch-horizontal angles at one and two years. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group.

CONCLUSIONS

The evacuation difficulty observed in patients with large colonic J-pouch reconstructions may be attributed to the development of a horizontal inclination within one year of surgery.

Induction of vascular endothelial growth factor after application of mechanical stress to retinal pigment epithelium of the rat in vitro

PURPOSE

To investigate the response to mechanical stress of vascular endothelial growth factor (VEGF) production by cultured retinal pigment epithelial (RPE) cells.

METHODS

A pulsatile stretch device was used in vitro. RPE cells of the second passage were seeded onto flexible-bottomed culture plates; then, at subconfluent culture, the plates were subjected to pulsatile stretch. Culture plates prepared in the same way but not subjected to stretch were used as controls. After stretching for 1 hour or 24 hours, conditioned medium for measurement of VEGF production by RPE cells was collected using a mouse VEGF immunoassay. To study the expression of VEGF in RPE cells, passaged-cultured RPE cells were exposed to pulsatile stretch for 0, 1, 3, or 14 hours. Total cytoplasmic RNA was then prepared from the RPE cells. Northern blot analysis was performed for VEGF, with G3PDH used as an internal control.

RESULTS

The expression and secretion of VEGF in RPE cells were increased by pulsatile stretching.

CONCLUSIONS

Results indicate that stretching of the RPE could result in increased production of VEGF, with associated risk for neovascularization and changes in the blood-retinal barrier.

Cooling effect on excimer laser photorefractive keratectomy

PURPOSE

To evaluate the effect of cooling on pain, corneal haze, and refractive outcome after excimer laser photorefractive keratectomy (PRK).

SETTING

Tokyo Medical and Dental University Hospital, Tokyo, Japan.

METHODS

The corneal surface was cooled before, during, and after laser ablation using a method called cooling PRK. Thirty-eighty highly myopic eyes of 38 patients whose spherical errors ranged from -8.00 to -18.75 diopters (D) were randomized into 2 groups: 16 eyes with conventional PRK and 22 eyes with cooling PRK. Postoperative pain was measured using the Visual Analogue Scale (VAS). Refraction, visual acuity, and complications were followed for up to 2 years. All data were analyzed and compared between groups to evaluate the cooling effect on PRK.

RESULTS

One day postoperatively, patients in the cooling PRK group had significantly less pain (P < .01). At 3 months, the haze score in the cooling PRK group was significantly less than in the conventional PRK group (P < .01). The residual refractive error was not significantly different between the 2 groups until 2 years, when it was greater in the conventional PRK (mean -5.09 D +/- 2.11 [SD]) than the cooling PRK group (-4.64 +/- 2.27 D). Ten eyes (62.5%) in the conventional PRK group and 15 eyes (68.2%) in the cooling PRK group were within +/- 1.00 D of the intended refraction. There were no serious complications in the cooling PRK group. Two eyes in the conventional PRK group had severe corneal haze and lost 2 Snellen lines of best corrected visual acuity.

CONCLUSION

Corneal cooling on PRK effectively reduced postoperative pain, corneal haze, and myopic regression.

Bilateral large peripapillary venous and arterial loops

BACKGROUND

Peripapillary loops of venous origin are extremely rare.

CASE

A 55-year-old woman was referred to us for further examination of peripapillary vascular abnormalities.

OBSERVATIONS

Fundus examination and fluorescein angiography clearly showed a venous and an arterial peripapillary loop in both her right and left fundi. The venous loop in the right eye was in a large hairpin configuration, extending into the retina about 1 disc diameter from the optic disc. Fluorescein angiography in the left eye revealed slow and irregular filling of dye into a venous loop that showed stasis of the bloodstream through the loop. Various retinal vascular abnormalities, including cilioretinal artery and triple branching of the retinal vein were also observed.

CONCLUSION

The findings in this case of bilateral peripapillary venous and arterial loops and unilateral trifurcation of retinal vein suggest that there could be an association in the other retinal abnormalities. Periodic follow-up examinations seem necessary.

Enlargement of colonic pouch after proctectomy and coloanal anastomosis: potential cause for evacuation difficulty

PURPOSE

Although the functional outcome after low anterior resection for rectal cancer using colonic J-pouch reconstruction is superior to that using conventional straight reconstruction, the one drawback of colonic J-pouch reconstruction is difficulty with evacuation. Recently it has been suggested that construction of a larger colonic J-pouch causes the evacuation difficulty. The purpose of this study was to elucidate the cause of evacuation difficulty with colonic J-pouch reconstruction.

METHODS

We compared pouchography of 26 patients with 10-cm colonic J-pouch reconstructions (10-J group) and 27 patients with 5-cm colonic J-pouch reconstructions (5-J group) at three months, one year, and two years after surgery. Functional assessments were performed one year postoperatively. Clinical function was evaluated using a questionnaire. Evacuation function was evaluated by the balloon expulsion and saline evacuation tests.

RESULTS

The greatest width of the pouch in the 10-J group in the anteroposterior view was significantly greater than that in the 5-J group at all three measurement times (3 months, 4.9 vs. 4 cm; P = 0.0011; 1 year, 9 vs. 5.6 cm; P < 0.0001; 2 years, 9.2 vs. 5.8 cm; P < 0.0001). The value in the 10-J group at one year after surgery was 1.9 times that at three postoperative months; in the 5-J group this ratio was 1.4. There was a significant difference between these ratios (P < 0.0001). No significant difference existed between the values at two years and one year after surgery in either the 10-J or the 5-J group. An evacuation difficulty was significantly more common in the 10-J group than the 5-J group. Evacuation function in the 10-J group was significantly inferior to that in the 5-J group.

CONCLUSIONS

The evacuation difficulty observed in patients with larger colonic J-pouch reconstructions is associated with excessive distention of the pouch occurring within one year of surgery.

Effect of streptozotocin-induced diabetes mellitus on type 1 deiodinase (D1) in inherited D1-deficient mice

We investigated the effects of streptozotocin (STZ)-induced diabetes on thyroid hormone levels, type 1 deiodinase (D1) activity and messenger RNA (mRNA) levels in inherited D1 deficient C3H mice in a comparative manner with control C57 mice. The apparent maximum velocity (Vmax) D1 values in C3H mice were 3% (liver) and 26% (kidney) of those in C57 mice. In C3H mice, similar serum T3, slightly higher T4, and 2.6-fold higher rT3 levels were observed compared with C57 mice. In STZ-induced diabetes, serum T4 level markedly decreased in both C3H and C57 mice. Serum T3 levels in STZ-C3H mice similarly decreased as in STZ-C57 mice. On the other hand, serum rT3 levels increased to 3.3-fold higher in STZ-C3H than in STZ-C57 mice. The Vmax values were decreased to 12% (STZ-C3H) and to 30% (STZ-C57) in liver, and decreased to 33% (both STZ-C3H and STZ-C57) in kidney. The changes in D1 mRNA levels in diabetes versus control were comparable to those of D1 activities in both strains. In summary, similar mechanism(s) to those which decrease the D1 expression and the serum T3 level in diabetes, function in D1 deficient C3H mice as in C57 mice. It appears that hepatic and renal D1 activity alone can not explain the similar reduction in T3 level in STZ-C3H mice and STZ-C57 mice.

P2Y2 receptor elevates intracellular calcium concentration in rabbit eye suprachoroid

Effects of ATP on the intracellular free calcium ion concentration ([Ca2+]i) in the rabbit eye suprachoroid were investigated by means of fura-2 microfluorophotometry. ATP application (10 to 100 microM) elicited a dose-dependent biphasic [Ca2+]i-increase: a fast phase typically peaking within 30 s and a following slow plateau phase, which lasted during the presence of ATP. The slow plateau phase was markedly diminished by removal of extracellular Ca2+, whereas the fast phase remained. An inhibitor of Ca2+ release from the sarcoplasmic reticulum (TMB-8), an endoplasmic Ca2+-ATPase inhibitor (thapsigargin) and a phospholipase C (PLC) inhibitor (U-73122) diminished the fast phase. A P2 receptor antagonist (Suramin) inhibited the ATP-induced [Ca2+]i-response. The potency order of ATP and related substances in producing the [Ca2+]i-elevation was UTP approximately equals ATP>ATP-gamma-S>ITP>ADP. beta,gamma-MethyleneATP, 2-methylthioATP and UDP evoked no response. This order is consistent with the P2Y2 receptor characteristics. Cross-desensitization between ATP and UTP excludes the co-existence of the other types of receptors. In conclusion, the ATP-induced [Ca2+]i-elevation in the rabbit eye suprachoroid was elicited by the Ca2+ release from the PLC-dependent, thapsigargin-sensitive intracellular Ca2+ storage sites by activating P2Y2 nucleotide receptors.

High ligation of the inferior mesenteric artery with hypogastric nerve preservation in rectal cancer surgery

We describe herein a technique of performing upward node dissection following high ligation of the inferior mesenteric artery for patients with T3 and T4 rectal carcinomas. The course of the hypogastric nerve is confirmed macroscopically during the procedure to ensure its preservation. This technique offers both increased radicality and the prevention of ejaculatory dysfunction.

Examination of nodal metastases by a clearing method supports pelvic plexus preservation in rectal cancer surgery

PURPOSE

In rectal cancer surgery preservation of urinary and sexual function is attempted by means of operations preserving the autonomic nerves of the pelvic plexus. Emergence of residual cancer because of a more shallow plane of dissection is a problem of concern with these methods, so we examined indications for pelvic plexus preservation.

METHODS

We studied 198 patients with rectal carcinoma who underwent abdominopelvic lymphadenectomy. Lymph nodes along the superior hemorrhoidal artery and middle hemorrhoidal artery medial to the pelvic plexus were defined as perirectal nodes, and nodes along the middle hemorrhoidal artery lateral to the pelvic plexus and along the internal iliac artery represented lateral intermediate nodes. Node metastases were examined by the clearing method.

RESULTS

Metastasis to perirectal nodes occurred in 12.5 percent in patients with pT1 tumors, 28.9 percent of those with pT2 tumors, and 50.0 percent of those with rectosigmoid junctional cancer. Metastasis to lateral intermediate nodes was absent in patients with pT1 or pT2 tumors and was as low as 2.5 percent in patients with rectosigmoid junctional cancer.

CONCLUSIONS

In patients with T1, T2, and rectosigmoid junctional cancer, perirectal node dissection is necessary, but chances of residual cancer should remain minimal when the pelvic plexus is preserved.

Processes of blue light-induced damage to retinal pigment epithelial cells lacking phagosomes

PURPOSE

To experimentally clarify the processes of the changes induced by blue light directly on the retinal pigment epithelium (RPE) before the formation of phagosomes or the accumulation of lipofuscin.

METHODS

We developed a new experimental method in which primary cultured cells of very young pigmented rats were exposed to several intensities and durations of blue light (wavelength = 440+/-10 nm).

RESULTS

At 1.0 mW/cm2, the damage was limited to mitochondria. At 2.0 mW/cm2, the cytoplasm exhibited large whorls of membrane or whorled inclusions, which were consistent with autophagic vacuoles. At 4.0 mW/cm2, the RPE cells showed lysis of the cytoplasm and a nucleus that was consistent with necrosis.

CONCLUSIONS

Our results suggested that damage induced by blue light to cultured RPE cells may originate in the mitochondria and end in necrosis. The type of cell death induced in the RPE by blue light seems to be determined mainly by the intensity of the light, but is also related to the duration of exposure.

[Clinical results and complications of refractive surgery]

PURPOSE

To evaluate the efficacy of photorefractive keratectomy (PRK) with a scanning type excimer laser MEL-60 (AESCLUP-MEDITEC, Co).

SUBJECTS AND METHOD

We performed PRK on 102 eyes of 62 myopic patients whose refraction ranged from-3.00 to -12.50 D (mean, -6.47 D) and examined the clinical results of postoperative refraction and complications.

RESULTS

At 12, 18, and 24 months after the operation, the mean refraction was -1.57 +/- 1.25D, -1.63 +/- 1.51 D and -1.73 +/- 1.47 D. At 12 months after the operation, 36 eyes (46.2%) were within +/- 0.5 D of intended correction, 61 eyes (78.3%) within +/- 1.0 D, and 76 eyes (97.4%) within +/- 2.0 D. Twenty-four months after the operation, 12 eyes (37.5%) were within +/- 0.5 D, 18 eyes (56.3%) within +/- 1.0 D and 29 eyes (90.6%) within +/- 2.0 D. The complications were as follows: keratitis filamentosa was observed in 10 eyes (10.5%), decrease of contrast sensitivity in 7 eyes (7.4%), subepithelial corneal haze in 4 eyes (1.2%), steroid-induced glaucoma was 2 eyes (2.1%), increase of astigmatism in 2 eyes (2.1%), decrease of best corrected visual acuity in 2 eyes (2.1%), and corneal ulcer in 1 eyes (1.1%).

CONCLUSION

PRK with a scanning type excimer laser MEL-60 was effective to reduce refractive error in low and mild myopia, but there were some complications, so that a long, careful follow-up seems necessary.

Coloanal anastomosis using a circular stapling device following perineal rectosigmoidectomy for rectal prolapse

Perineal rectosigmoidectomy with a hand-sewn anastomosis is thought to be the most appropriate procedure for elderly patients deemed unfit to tolerate a major abdominal operation. However, the use of a circular stapling device to perform the coloanal anastomosis following rectosigmoidectomy shortens the operative time and provides a more secure anastomosis than the traditional hand-sewn technique.

Effect of nicotine on type 2 deiodinase activity in cultured rat glial cells

Intracellular generation of triiodothyronine (T3) from thyroxine (T4) by type 2 deiodinase (D2) in the mammalian brain, plays a key role in thyroid hormone action. The presence of D2 in rat astrocytes suggests the importance of glial cells in the regulation of intracellular T3 levels in the rat central nervous system (CNS). To analyze further the factors that regulate D2 activity in the CNS, we investigated the effects of nicotine and of mecamylamine, which inhibits the binding of nicotine with nicotinic acetylcholine receptors, on D2 activity in cultured mixed glial cells of the rat brain. We incubated cultured mixed glial cells obtained from neonatal Wistar rats in the presence of 10 mM dithiothreitol, 2 nM [125I] reverse T3 and 1 mM 6-N-propyl-2-thiouracil for 2 h at 37 degrees C, and the released 125I- was counted in a gamma counter. D2 activity of cultured cells was dependent on the temperature and the amount of protein. The basal D2 activity of rat mixed glial cells was 1.9 +/- 0.2 fmol of I- released/mg protein/h (mean +/- SEM). The addition of 10(-11), 2 x 10(-11), 10(-10), and 10(-9) M nicotine significantly increased D2 activity to approximately 2.2-, 2.4, 3.5- and 2.9-fold the basal level, respectively. D2 activity stimulated by 10(-8) M nicotine (2.5-fold) reached a peak after 9 h incubation. The stimulatory effect of nicotine was completely blocked by 10(-6) M mecamylamine. In conclusion, nicotine increases D2 activity probably via nicotinic acetylcholine receptors, and may influence brain function, at least in part, by affecting thyroid hormone metabolism.

[Developmental mechanism of low myopia and therapeutic possibilities. A review]

We studied the developmental mechanism of low myopia and the possibility of its drug treatment. I. Prevalence of myopia. According to surveys by the Japanese Ministry of Education, Science, Sports and Culture, the frequency of myopia in school children has gradually increased. We examined office workers from 20 to 60 years of age over a 3-year period. Myopia progression was observed in the thirties and fourties. Late-onset myopia is an important problem around the world. II. Developmental mechanism of low myopia. 1. Reduction of refraction after cycloplegia was statistically significant in adults after their twenties. We measured accommodative hysteresis after a close visual task. Accommodative hysteresis persisted for a long time in late-onset and adult-onset myopia. Continuous ciliary contraction seems to be related to late-onset myopia. 2. Bovine ciliary muscle strips were suspended in a Magnus double tube. The changes in isometric tension of the strips, when chemicals were added, were measured with a force-displacement transducer. After the addition of the cholinergic agonist carbachol, the strips of ciliary muscle produced a tonic contraction. When the muscarinic receptor antagonist cyclopentolate was added, relaxation was produced. After the addition of ET-1, a dual response occurred which consisted of a moderate relaxation and a long-lasting contraction. The mean contraction caused by ET-1 was weak but continuous compared to carbachol. The contractile response was inhibited by an ETA receptor antagonist. Also, when takusha, one component of gorei-san, a Chinese drug, was added to the ciliary muscle strips, contraction with ET-1 was attenuated. Contraction of the ciliary muscle with ET-1 was attenuated after addition of sodium nitroprusside (SNP), an NO donor. This reaction suggests that NO causes relaxation of the bovine ciliary muscle through the activation of guanylyl cyclase and an increase in cyclic GMP. Currently, at least 5 muscarinic receptor subtypes are recognized; they are named M1 to M5. The effects of M1, M2, and M3 on the contractile response to transmural electrical stimulation of the bovine ciliary muscle were studied. The contractions produced by transmural electrical stimulation were greatly attenuated by 4-DAMP as an M3 antagonist. 3. We measured autofluorescence of the lens by fluorophotometry. A statistically significant relation was found between autofluorescence of the lens and refraction. 4. Possibility of axial elongation: The anterior and posterior suprachoroidal spaces are different anatomically and physiologically. When the choroid is stretched forward by accommodation, the intraocular pressure may exert more influence on the posterior part of the sclera, than on the anterior part. Using a fluorophotometer, fluorescence leakage at a site 3 mm in front of the retina was examined. Intensity of fluorescence 3 mm in front of the retina was strong in late-onset myopia. This may indicate disturbance of the barrier of the retinal pigment epithelium. When cultured fibroblasts of the sclera of the chick embryo was stretched by a stretching apparatus, proliferation of the cultured cells was inhibited. Therefore, some influence may involve the posterior part of the eyeball. III. Possibility of drug treatment of low myopia: From these results, muscarinic receptor antagonists (especially M3), ET receptor agtagonists, and NO donors are possible drugs for low myopia treatment. As there are many causative factors of low myopia, there are several treatment methods to be evaluated.

Zinn-Haller arterial ring observed by ICG angiography in high myopia

AIMS

To delineate the entire Zinn-Haller arterial ring angiographically in vivo.

METHODS

382 highly myopic eyes (210 patients) with refractive errors greater than -8.25 D were examined using indocyanine green (ICG) videoangiography. A control group of 80 eyes (40 patients) had refractive errors within plano +/- 3D.

RESULTS

The Zinn-Haller ring was visible in 206 of 382 highly myopic eyes (53.9%) by ICG angiography. Although only a part of the Zinn-Haller ring was visible in 162 of 206 eyes, in the remaining 44 eyes it was observed almost completely around the optic nerve head. No anastomotic channels between lateral and medial short posterior ciliary arteries were filled by ICG angiography. In 22 of the 44 eyes (50.0%) the Zinn-Haller ring was supplied by branches of the lateral and medial short posterior ciliary arteries; in seven eyes, it was supplied only by the lateral short posterior ciliary artery; and in seven eyes, it was supplied only by the medial short posterior ciliary artery. In none of the control subjects was the Zinn-Haller ring visible by ICG angiography.

CONCLUSIONS

The Zinn-Haller ring observed by ICG angiography was not a complete collateral circle between lateral and medial posterior ciliary arteries. Also, the patterns in supply vessels to the Zinn-Haller ring varied. ICG angiography made possible the detailed observation of the Zinn-Haller ring in human eyes in vivo.

Maternal thyroid function in multiple pregnancy: the variable thyrotropic activity of human chorionic gonadotropin

The present study was undertaken to evaluate thyroid function and thyrotropic action of hCG in multiple pregnancy. We examined serum samples from 9 multiple pregnant women (3 triplets and 6 twins) and 27 singleton pregnant women as control subjects. Serum hCG levels in multiple pregnancy were higher than those in singleton pregnancy in the second and third trimesters (P < 0.01). The mean free T3 and T4 concentrations in multiple pregnancy did not differ from those in singleton pregnancy in each trimester. Serum hCG levels showed a statistically significant positive correlation with free T3 and T4 levels in singleton pregnancy (P < 0.001). However, these correlations were not observed in multiple pregnancy. Thyroid stimulation activity (TSA) determined by cAMP accumulation in FRTL-5 cells in multiple pregnancy sera was significantly higher than that in singleton pregnancy in the first trimester (P < 0.05), but did not differ in the second and third trimesters. Moreover, TSA did not show any correlation with serum hCG levels in multiple pregnancy in contrast with the results in normal pregnancy. A bioactivity/immunoreactivity ratio of hCG in multiple pregnancy was lower than in singleton pregnancy in the second and third trimesters. The discrepancy between immunoreactivity and thyrotropic activity of hCG may be caused by the variable thyrotropic potency of heterogeneous hCG molecules in multiple pregnancy.

Quantitative measurements for type 1 deiodinase messenger ribonucleic acid in human peripheral blood mononuclear cells: mechanism of the preferential increase of T3 in hyperthyroid Graves' disease

To evaluate the regulatory mechanism of human Type 1 iodothyronine deiodinase (D1) gene expression, we measured the D1 mRNA levels in peripheral blood mononuclear cells (PBMC) in normal control subjects and in patients with Graves' disease. We used competitive reverse transcriptase-polymerase chain reaction with the deleted complimentary RNA of D1 as the standard for quantification. The D1 mRNA levels in PBMC were increased significantly in patients with Graves' disease compared with that in normal controls. There was a significant (p < 0.01) positive correlation (r=0.698) between D1 mRNA level and serum T3 concentration. When PBMC from the normal volunteers were cultured with various doses of T3, the quantity of D1 mRNA increased significantly in a dose-dependent manner. These findings indicate that PBMC D1 mRNA is actually up-regulated by T3 in vivo, and we postulate that a vicious spiral of increasing T3 and D1 is responsible for the exacerbation of thyrotoxicosis in hyperthyroid Graves' disease.

Observation of ultrastructural changes in cultured retinal pigment epithelium following exposure to blue light

BACKGROUND

The retina can be damaged by light even when levels of energy are well below the threshold for thermal damage, and the experimental damage of the retinal pigment epithelium (RPE) may be induced more easily by blue light than by longer wavelengths of visible light. The present study demonstrates the ultrastructural damage produced by exposure to blue light in cultured RPE.

METHODS

Long-Evans rats were enucleated 8-10 days after birth for primary culture. One week after seeding, the monolayer culture of RPE cells was exposed to a cool blue light (wavelength = 440 +/- 10 nm) for 36 h (12 h/day, 3 days) at 2.0 mW/cm2. Transmission electron microscopy was used to compare the exposed RPE with the control. The entire experiment was repeated 3 times independently.

RESULTS

The cytoplasm of the exposed RPE exhibited degenerative changes, such as large whorls of membrane, lamellar whorls and whorled inclusions.

CONCLUSION

The RPE cells can be damaged directly by blue light after excluding the possible influence of phagosomes. This primary culture of RPE can also serve as an in vitro model for the study of light damage to the RPE.