Angiographic leakage of polypoidal choroidal vasculopathy on indocyanine angiography.

BACKGROUND: There is no detailed report about the angiographic leakage of polypoidal choroidal vasculopathy (PCV) lesions on indocyanine green (ICG) angiography. This study aimed to investigate the angiographic leakage of polypoidal lesions in PCV on ICG angiography. METHODS: One hundred and forty-four eyes of 137 patients diagnosed as PCV were prospectively observed. Fundus examination, fluorescein angiography, and ICG angiography were performed. Leakage of polypoidal lesions and clinical features were recorded according to the angiograms. RESULTS: In all 144 eyes, 110 eyes showed angiographic leakage (leakage group) on ICG angiography and three subtypes of leakage group were noted, which were polypoidal dilations leakage (47 eyes, 42.7%), branching vascular networks leakage (14 eyes, 12.7%) and leakage of both (49 eyes, 44.5%). The other 34 eyes showed regression of polypoidal lesions (regression group). In leakage group, the rates of pigment epithelial detachment (PED), best corrected visual acuity (BCVA) < 0.1 and old subretinal hemorrhages were 56.4% (62 eyes), 19.1% (21 eyes), and 4.6% (5 eyes) respectively, compared with 8.8% (3 eyes), 50% (17 eyes) and 38.2% (13 eyes) of regression group (P < 0.001). The history of regression group was significantly longer (P < 0.001). CONCLUSIONS: Angiographic leakage and regression can be observed in PCV lesions. Leakage of both polypoidal dilations and branching vascular networks is the most common subtype in leakage group. PCV in leakage group is more likely to be related to PED, better BCVA and shorter history, while PCV regression group tends to relevant to old subretinal hemorrhage, worse BCVA and longer history. This may reflect that the former is active or in the early course while the later is resting or in the late phase of PCV.

[Reversal effect of haloperidol on doxorubicin resistance and chloride channel inhibition in erythroleukemic cell K562/Dox].

OBJECTIVE: To investigate the reversal effect of haloperidol (Hal) on doxorubicin (Dox) resistance and its inhibition effect on P-glycoprotein and swelling-activated chloride channel in Dox-resistant erythro-leukemic cell line K562/Dox. METHODS: Tumor cell proliferation was measured by LDH assay. mRNA expressions of P-glycoprotein (MDR1), glutathione S-transferase Pi (GSTpi) and MDR-associated protein (MRP) of K562/Dox treated with Hal were assayed by RT-PCR. Chloride-sensitive dye MQAE was loaded into K562/Dox cells and the intracellular fluorescence intensity was measured to evaluate the effect of Hal on chloride channel in swelling-activated K562/Dox cells. Coulter counter ZM and Channelyzer 256 were used to measure cell volume regulation. RESULTS: Hal significantly reversed Dox resistance in K562/Dox cells after 12.50, 6.25 and 3.12 micromol/L Hal treatment, the chemosensitivity to Dox increased by 8.61, 4.35 and 2.25 times respectively. After treatment with Hal 12.50 micromol/L, MDR1 and MRP mRNA expression were gradually down-regulated in a time-dependent manner on d1-d3, reducing to 76.3% and 64.6% of the control level on d3 (P < 0.05), while GSTpi mRNA expression decreased by 66.1% (P < 0.05) on d1-d2, and began to recover on d3. The swelling-activated chloride channel and cell regulatory volume decreased (RVD) in K562/Dox cells were also inhibited by Hal. Under hypotonic challenge the cellular fluorescence intensity which represented chloride concentration declined by (34.46 +/- 5.91)%. After adding 6.25 micromol/L and 18.75 micromol/L Hal, the hypotonic challenge only caused decrease in fluorescence intensity by (24.43 +/- 3.25)% and (16.63 +/- 4.98)% (P < 0.01). RVD in hypotonic condition was (84.95 +/- 5.69)%. RVD under hypotonic condition with 6.25 micromol/L and 18.75 micromol/L Hal were (51.12 +/- 6.01)% and (39.51 +/- 4.79)% respectively (P < 0.01). CONCLUSION: A nontoxic concentration of haloperidol can significantly reverse drug resistance through a multi-pathway effect, including down-regulating mRNA expressions of MDR, GSTpi and MRP, inhibition of swelling-activated chloride channel and RVD in K562/Dox cells.

[The conversion of macular function in diabetic macular edema after vitreous surgery].

OBJECTIVE: To evaluate the conversion of macular function in diabetic macular edema (DME) after vitreous surgery. METHODS: Seventeen eyes of 16 patients were assessed after pars plana vitrectomy for DME. Multifocal electroretinogram (mfERG) techniques were used to evaluate the effects of treatment on macular visual function, and retinal foveal thickness was determined by optical coherence tomography before and after vitrectomy. Patients were followed up continually for 7 months. The correlation between the change of tomographic features and visual functions were analyzed. RESULTS: During the follow-up period, the retinal function in macular areas recovered and the foveal thickness decreased gradually. While compared with preoperative values, the response of positive wave (P1) have shown decreases in implicit time and increases in amplitude since the forth and fifth postoperative month respectively (P < 0.05). While compared between each postoperative period, the P1 responses have increased significantly since the forth postoperative month. The correlation between the increase of P1 amplitude in macular area and the decrease of retinal foveal thickness was significant (r = 0.954, P < 0.001). CONCLUSIONS: Macular function get improvement gradually in DME after vitreous surgery; The restoration of macular function is coincident with the reduction of macular edema.

[Comparison of genetic polymorphism of cytochrome CYP2C19 between men and women in Chinese population].

AIM: To assess the effect of gender on genetic polymorphism of cytochrome CYP2C19 in Chinese population. METHODS: The genetic polymorphism of 140 healthy Chinese were analysed by PCR-RFLP (restriction fragment length polymorphism). RESULTS: Of 52 genotyped male subjects, 23 (44.23%) were homozygous for wildtype (wt/wt), 6 (11.54%) were homozygous for CYP2C19 m1 (m1/m1), and 23 (44.23%) were heterozygous for CYP2C19 m1 or CYP2C19 m2 (wt/m1 or wt/m2); and among the 88 genotyped female subjects, 31 (35.23%) were homozygous for wildtype (wt/wt), 13 (14.82%) were homozygous for CYP2C19 m1 (m1/m1), and 44 (50.0%) were heterozygous for CYP2C19 m1 or CYP2C19 m2 (wt/m1 or wt/m2); no homozygous genotype for CYP2C19 m2 (m2/m2) was found in the study. CONCLUSION: There is no statistical difference in ocurance of wt/wt and m1/m1 between in male and in female, so gender have no significant effect on genetic polymorphism of cytochrome CYP2C19.

Fundus analysis and visual prognosis of macular hemorrhage in pathological myopia without choroidal neovasculopathy.

PURPOSE: To analysis and evaluate the fundus characteristics and visual prognosis of macular hemorrhage in pathological myopia without choroidal neovasculopathy. METHODS: Thirty-seven patients (38 eyes) of pathological myopia with macular hemorrhage and without choroidal neovascularization (CNV) underwent color photograph and fundus fluorescein angiography (FFA) examinations. Indocyanine green angiography (ICGA) was also performed on 11 patients (11 eyes). Follow-up ranged from 3 to 21 months. RESULTS: The macular hemorrhage in pathological myopia without CNV demonstrated oval, less than 1PD, without edema and exudation. Lacquer cracks appeared at the site of previous subretinal bleeding in 84.2% of the eyes. The visual acuities were improved in 81.6% of eyes during the follow-up period. ICGA revealed linear hypofluorescence in 7 of 11 eyes (63.6%), indicating a ruptured Bruch's membrance at the onset of subretinal bleeding. CONCLUSION: A rupture of choriocapillaris complex and Bruch's membrane causes macular hemorrhage of pathological myopia without CNV, leading to the formation of a new lacquer crack. Its prognosis is favorable.

Impairment of optic path due to radiotherapy for nasopharyngeal carcinoma.

PURPOSE: To evaluate the impairment of optic path caused by radiotherapy for nasopharyngeal carcinoma (NPC). METHODS: Visual evoked potential was used to evaluate the functional impairment of optic path by an 8 MV linear accelerator or 60Co gamma-ray radiotherapy in 63 (23 women and 40 men) patients with nasopharyngeal carcinoma before radiotherapy, at the end of radiotherapy, 6 months and 1, 2 and 3 years after their radiotherapy respectively. RESULTS: In the female group, the latency of VEP elicited by the three types of elements significantly delayed 2 and 3 years after radiotherapy than that before radiotherapy, at the end of radiotherapy, 6 months and 1 year after radiotherapy; there were no significant difference among VEP amplitudes elicited by the three types of elements before and after radiotherapy. In the male group, the latency of VEP elicited by the medium and the small elements significantly delayed 1 year after radiotherapy than that before radiotherapy and at the end of radiotherapy, the VEP latency elicited by the small elements was significantly prolonged 3 years after radiotherapy compared to that just after radiotherapy, while the VEP amplitude elicited by the large elements was significantly attenuated 1 year after radiotherapy compared to those before and just after radiotherapy. CONCLUSIONS: In the female group, the significant prolongation of VEP latency happened at the end of radiotherapy and lasted for 3 years, while the VEP amplitude did not change significantly during the 3 years after radiotherapy. It indicates that the sustained impairment by radiation within the female visual nerve system starts at the end of radiotherapy, but the impairment was mild. In the male group, the significant prolongation of VEP latency mostly happened 1 or 2 years after radiotherapy. It was shown that the radiotherapy for nasopharyngeal carcinoma certainly injured the optic path, and there was difference in the impairment between the two sexes.

Scotopic sensitivity of central retina in early age-related macular degeneration.

PURPOSE: To test scotopic sensitivity and investigate whether there is rod system dysfunction in the central retina in early age-related macular degeneration (AMD). METHODS: Scotopic (450 nm stimulus) and photopic (white light stimulus) sensitivity in 24 patients with early AMD was measured at 81 loci in central 25 degrees of retina, and compared with the age-match normal controls. RESULTS: Mean scotopic sensitivity of AMD patients was significantly lower than that of the normal controls. The patients of reduced scotopic sensitivity were more than those of reduced photopic sensitivity. Scotopic sensitivity deficit decreased with increasing eccentricity with the greatest deficit was 2.5 degrees to 5.0 degrees. CONCLUSIONS: Scotopic sensitivity was decreased in the early stage of AMD. The parafoveal rod cells were selectively damaged in AMD. Scotopic sensitivity testing in macula may be a useful tool to diagnose and measure the fundus dysfunction of AMD.

Exploration of multifocal rod electroretinograms recording in human.

PURPOSE: To test the feasibility of recording rod multifocal electroretinograms (ERG) in humans and observe appropriate recording conditions. METHODS: Multifocal rod ERG were recorded using a stimulus array of 61 equalsized hexagons in two normal subjects after the dark adaptation. Flashes were blue (W47B). Blank frames between two successive flashes of hexagons varied from 0 to 14. Length of the m-sequence, bandwidth, flash frequency, flash intensities and background intensities were changed to obtain appropriate recording conditions for the clinical use. RESULTS: Multifocal rod ERG were clearly recordable and well formed. They had an early implicit time, very small negative wave and a late implicit time, large positive wave. The positive wave was bimodal, whose timing and waveform were similar to the full-field rod ERG. The local response amplitudes can be suppressed with increase in flash frequency or background intensity, decrease in flash intensity or the size of stimulus elements. CONCLUSIONS: Multifocal rod ERG can be recorded in human and can provide topographical maps of retinal function that have clinical usage. 2(12)-1 m-sequence length, 3F blank frames and 3 - 300 Hz bandwidth were suggested to appropriate recording conditions.

[The study on binocular visual field summation and its possible mechanism].

PURPOSE: To observe the summation effect of binocular visual field in persons with normal or abnormal visual field and study the validity of four kinds of theory (best eye, average eye, best location, binocular summation) on binocular visual field formation. METHODS: The monocular and binocular visual field were tested in 15 cases with normal visual field and 58 cases of different kinds of ocular diseases with abnormal visual field. RESULTS: The mean rates of summation in normal visual field group and abnormal group were 93.00% and 93.10% respectively with no significant difference (P > 0.05). The mean degree of binocular visual field summation of normal visual field group was 7.05. The abnormal group had a greater variation of summation degree than that of normal group. The comparison of four theoretic simulating mathematical methods with the tested mean retinal sensitivity (MS) of binocular visual field in both groups showed minimum difference between the MS calculated by the model of best location and the actual MS value. CONCLUSIONS: Binocular summation is a common vision phenomena. In the four kinds of theory on binocular visual field formation, the model of best location can best reveal the phenomena of binocular visual field summation.