Microperimetry-guided inverted internal limiting membrane flap site selection to preserve retinal sensitivity in macular hole with glaucoma.

Purpose: In cases of macular hole (MH) that is difficult to close, including large, chronic, or highly myopic cases, the inverted internal limiting membrane (ILM) flap technique is often preferred and yields favorable surgical outcomes as compared to those yielded by conventional ILM peeling. However, no consensus exists on the optimal location and area for peeling and inverting the ILM, since multiple alternative methods have been reported alongside the original method. Several adverse effects associated with ILM peeling have been documented, including mechanical impairment of the retinal nerve fiber layer and decreased retinal sensitivity. Particularly, when glaucoma is concomitant, the retinal nerve fiber layer is fragile, raising concerns about a decrease in retinal sensitivity. Consequently, in patients with large MH alongside glaucoma, the goal is to select a procedure that maximizes the closure rate of the MH while minimizing any negative impact on glaucomatous visual field impairment. However, a technique for this purpose has not yet been validated. Observations: A woman in her 60s presented with visual impairment (20/50), metamorphopsia, and central scotoma of unknown onset in the right eye. A full-thickness MH accompanied by epiretinal proliferation (EP) was identified, with a minimum diameter of 506 µm. Although a retinal nerve fiber layer defect was not evident on ophthalmoscopy, thinning of the ganglion cell complex (GCC), extending from the superotemporal aspect of the optic disc, was observed on optical coherence tomography. Both microperimetry and static visual field testing revealed reduced retinal sensitivity in the thinned GCC areas. A pars plana vitrectomy combined with cataract surgery was performed to address her condition. The EP was embedded into the foveal cavity. On the basis of the microperimetry results, the ILM within the absolute scotoma region was peeled on the superotemporal side of the fovea to create a flap, which was then placed over the MH. A gas tamponade was applied, and the patient was maintained in a prone position postoperatively. The MH was successfully closed after the surgery, resulting in visual improvement (20/25). No decline in retinal sensitivity after the surgery was observed. Conclusions and importance: Determining the location and area of the inverted ILM flap on the basis of microperimetry results is a promising patient-tailored strategy for treating MH concomitant with glaucoma while preventing further ILM peeling-associated reduction in the retinal sensitivity.

Japan-epiretinal membrane (J-ERM) registry: A prospective cohort study protocol investigating the surgical outcome of epiretinal membrane.

BACKGROUND: Epiretinal membrane (ERM) causes visual impairment such as reduction in visual acuity and metamorphopsia due to retinal traction. With the improvement of optical coherence tomography (OCT) and microincision vitrectomy surgery (MIVS), the surgery of ERM has significantly advanced. However, there have been no large-scale studies on the following: (1) how to evaluate visual impairment in ERM, (2) the relationship between OCT findings and visual function, (3) when is the optimal timing of surgery, and (4) the relationship between the surgical instruments as well as techniques and prognosis. The purpose of this study was to obtain evidence regarding these ERM surgeries. METHODS AND DESIGN: This is a prospective, multicenter cohort study of ERM surgery in Japan from March 1, 2023, to March 31, 2027 (UMIN000048472, R-3468-2). Patients who underwent ERM surgery during the study period and agreed to participate in this study will be included. The goal is to have a total of 5,000 eyes surgically treated for ERM. The following data will be collected: age, gender, medical history, subjective symptoms, visual function before and 6 and 12 months after surgery, clinical findings, OCT data, surgical technique, instruments used in surgery, and complications. DISCUSSION: The results of this study will support the surgical decisions and procedures in ERM practices.

Evaluation of epiretinal membrane formation after scleral buckling for treating rhegmatogenous retinal detachment: En face optical coherence tomography image-based study.

PURPOSE: To assess epiretinal membrane (ERM) formation, severity, and the associated risk factors after scleral buckling using en face optical coherence tomography (OCT) images. METHODS: Medical records of 61 consecutive patients (66 eyes) with rhegmatogenous retinal detachment who underwent scleral buckling were retrospectively reviewed. Posterior vitreous detachment (PVD) was determined based on B-scan OCT images. En face OCT images were used to visualize the ERM and retinal folds. ERM formation was identified by comparing en face images pre- and post-surgery. The maximum depth of the retinal folds (MDRF) was measured using en face imaging to objectively assess traction strength. RESULTS: ERM formation occurred in 15 (22.7%) eyes at the final visit; the foveal pit was preserved in all cases. Parafoveal retinal folds were present in 5 (7.6%) eyes, with a mean MDRF of 21.8 ± 12.6 µm. No significant difference was observed in best-corrected visual acuity (logarithm of the minimal angle of resolution) between the ERM formation (-0.019 ± 0.128) and non-ERM formation (-0.001 ± 0.213) groups at the final visit (P = 0.593; Mann-Whitney U test). Multivariate logistic regression analysis revealed that older age and the presence of PVD were significant risk factors for ERM formation (odds ratio 1.07, 95% confidence interval 1.01-1.14, P = 0.032; odds ratio 5.26, 95% confidence interval 1.06-26.10, P = 0.042; respectively). CONCLUSION: ERM occurred in 22.7% of cases but was mild and did not affect visual acuity. Older age and the presence of PVD are risk factors for ERM formation.

[Characteristics of ethical dilemma and behavior in the support process of older adults and their families among nurses at a community general support center in Japan].

Objectives　This study was aimed at clarifying characteristics of ethical dilemmas and behaviors in the support process of older adults and their families among nurses at community general support centers.Methods　A self-administered questionnaire survey was mailed to 449 nurses at community general support centers in Tokyo. Question items enquired their age, employment license, years of experience as a nurse, the presence of ethics-related organizations, number of cases in which nurses faced difficulties in supporting older adults and their families in decision making over the past year, the ethical dilemmas they experienced and their situations, and ethical behavior in the process of supporting older adults and their families.Results　From the 143 responses (response rate: 31.8%), 135 (valid response rate: 30.1%) nurses were analyzed. Overall, 43.0% and 27.4% of the participants were in their 50s and 40s, respectively. Of these, 77.0% and 23.0% were nurses and public health nurses, respectively. In total, 52 (38.5%) respondents had an ethics-related organization. The average number of cases in which the respondents faced difficulties in supporting older adults and their families in decision making over the past year was 8.3 (standard deviation, 12.5). Of these, the average number of cases in which they faced difficulties in making ethical decisions was 4.1 (standard deviation, 6.0). Regarding the perception of ethical dilemmas, 113 (83.7%) answered "often" or "sometimes." Ethical dilemma situations included "the intentions of the user and family were different, and I had trouble deciding what to respect" 95 (84.1%); "the user's intention was different from my judgment as a professional, and I had trouble deciding what to respect" 64 (56.6%); and "the intention of the user and neighbors were different, and I had trouble deciding what to respect" 56 (49.6%). Ethical behaviors included "I observe the management rules in my organization regarding personal information data" 116 (85.9%); "I provide easy-to-understand explanations appropriate to the user's situation" 115 (85.2%); and "I decide on a support policy with several staff members when self-decision making is difficult due to the user's situation" 113 (83.7%).Conclusion　More than 80% of the nurses perceived ethical dilemmas. Characteristics of the situations were that users and their families, users and professionals, and users and their neighbors had different intentions. Further research should be conducted on ethical issues related to community-based integrated care.

Accuracy of ultrasound vs. Fourier-domain optic biometry for measuring preoperative axial length in cases of rhegmatogenous retinal detachment.

PURPOSE: To identify a method for accurately measuring preoperative axial length (AL) in cases of rhegmatogenous retinal detachment (RRD). STUDY DESIGN: Retrospective study. METHODS: This retrospective study included 83 eyes of 83 patients who underwent vitrectomy for RRD and had both preoperative and postoperative data for AL. Preoperative AL measurements for the affected eye were obtained using ultrasound (aUS-AL) and compared with those for affected and fellow eyes measured using optical biometry (aOB-AL and fOB-AL, respectively). Absolute differences between preoperative aUS-AL, aOB-AL, or fOB-AL measurements and postoperative AL (aPost-AL) were examined. RESULTS: In the 41 eyes without macular detachment, the absolute difference between aOB-AL and aPost-AL (0.06±0.07 mm) was significantly smaller than between aUS-AL and aPost-AL (0.21±0.18 mm) and that between fOB-AL and aPost-AL (0.29±0.35 mm) (P = 0.017 and P < 0.001, respectively). In the 42 eyes with macular detachment, the absolute difference between aOB-AL and aPost-AL (1.22±2.40 mm) was significantly larger than between aUS-AL and aPost-AL (0.24±0.24 mm) and between fOB-AL and aPost-AL (0.35±0.49 mm) (P = 0.006, P = 0.016, respectively). CONCLUSION: The current findings suggest that aOB-AL is more accurate than aUS-AL or fOB-AL in cases of RRD without macular detachment, while aUS-AL or fOB-AL is more accurate than aOB-AL in cases with macular detachment.

A Case of Acute Zonal Occult Outer Retinopathy in which Oct en Face Imaging Was Useful for Diagnosis and Follow-up.

A 23-year-old woman presented with a 1-month history of visual abnormalities in her right eye. A visual field test revealed temporal abnormalities in the right eye. Optical coherence tomography revealed an indistinct ellipsoid zone (EZ) on the B-scan image and hyporeflective areas in the EZ layer on the en face image in the right eye. We diagnosed the patient with acute zonal occult outer retinopathy. Visual field tests and B-scan images improved to almost normal at 6 months, but hyporeflective areas remained on the en face images. Thus, en face images may be more sensitive at detecting abnormalities in the outer retina than other modalities.

Quantitative Analyses of Retinal Traction Force and Metamorphopsia in Lamellar Macular Hole and Related Diseases.

Purpose: To investigate the involvement of retinal traction in the pathogenesis of lamellar macular hole (LMH) and related diseases based on OCT-based consensus definition. Design: Retrospective, observational study. Participants: Seventy-two eyes with LMH, epiretinal membrane foveoschisis (ERM-FS), or macular pseudohole (MPH). Methods: To quantitatively evaluate the involvement and strength of retinal traction in their pathogenesis, retinal folds were visualized with en face OCT imaging, and the maximum depth of the parafoveal retinal folds (MDRF) was measured. Metamorphopsia was quantified by measuring the minimum visual angle of dotted lines needed to cause it to disappear using M-CHARTS (Inami). Main Outcome Measures: Maximum depth of retinal folds and M-CHARTS scores. Results: Of the 72 eyes, 26 were classified as having LMH, 25 as having ERM-FS, and 21 as having MPH. Parafoveal retinal folds were observed in 7 (26.9%) eyes with LMH, 25 (100%) with ERM-FS, and 21 (100%) with MPH. The MDRF (7.5 ± 17.6 µm) was significantly smaller in LMH than in ERM-FS (86.3 ± 31.4 µm) and MPH (74.5 ± 24.6 µm) (both P < 0.001), whereas no significant difference in MDRF between MPH and ERM-FS was observed (P = 0.43). A significant positive correlation between MDRF and M-CHARTS scores was observed in ERM-FS and MPH (P = 0.008 and 0.040, respectively) but not in LMH (P = 0.073). Conclusions: Retinal traction was significantly weaker in the LMH group than in the ERM-FS and MPH groups. The MDRF was significantly associated with the degree of metamorphopsia in the ERM-FS and MPH groups. These results provide insights into the diseases' pathophysiology and treatment strategy.

Epiretinal Membrane Impairs the Inner Retinal Layer in a Traction Force-Dependent Manner.

Purpose: To investigate the relationship between retinal traction force and impairment of the inner retinal layer in patients with epiretinal membrane (ERM). Design: Nonrandomized, retrospective consecutive case series. Participants: Two hundred nine eyes of 201 patients with idiopathic ERM who underwent vitrectomy for idiopathic ERM were enrolled. Methods: Retinal folds caused by ERM were visualized using en face OCT, and the maximum depth of retinal folds within the parafovea (MDRF) was measured. Focal macular electroretinogram (ERG) was used to measure the amplitude and implicit time of each component for the ERM eyes and the normal fellow eyes. B-scan OCT images were used to measure the thicknesses of the inner nuclear layer (INL) and outer nuclear layer (ONL) + outer plexiform layer (OPL). Expression of α-smooth muscle actin (α-SMA) in surgically removed ERM specimens was quantified by reverse-transcription polymerase chain reaction. Main Outcome Measures: We analyzed the relationship between MDRF and the relative amplitudes of focal macular ERG (affected eye/fellow eye), the relationships between MDRF and the mean INL thickness and ONL+OPL thickness, comparison of INL thickness and ONL+OPL thickness for each area when cases were classified according to MDRF localization in the ETDRS chart, and the relationship between MDRF and the relative expression of α-SMA in the ERM specimens. Results: The MDRF significantly correlated with the relative amplitudes (affected eye/fellow eye) of b-waves and oscillatory potentials (r = -0.657, P = 0.015; r = -0.569, P = 0.042, respectively) and the mean INL thickness and ONL+OPL thickness (r = 0.604, P < 0.001; r = 0.210, P = 0.007, respectively). However, only the INL thickness progression rate was significantly correlated with the MDRF progression rate (r = 0.770, P < 0.001). On case stratification by localization of MDRF based on the ETDRS chart, in regions other than temporal regions, the INL thickness was significantly greater in regions with MDRF than in other regions. The MDRF significantly correlated with α-SMA expression in the ERM specimens (r = 0.555, P = 0.009). Conclusions: The findings suggest that ERM impairs the inner retinal layer in a traction force-dependent manner. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

A factor for predicting simultaneous internal limiting membrane peeling during epiretinal membrane removal: swept-source optical coherence tomography-based evaluation of epiretinal membrane adhesion to the retina.

PURPOSE: To investigate preoperative factors associated with simultaneous internal limiting membrane (ILM) peeling during epiretinal membrane (ERM) removal. STUDY DESIGN: Observational cross-sectional study. METHODS: We retrospectively reviewed 60 eyes with idiopathic ERM that underwent vitrectomy. The gap between the ERM and ILM was visualized using en face optical coherence tomography. The depth and width of the ERM-ILM gap at the initiation site of ERM removal were measured, and the relationship between preoperative factors including these parameters and simultaneous ILM peeling during ERM removal was investigated. RESULTS: The ILM was simultaneously peeled during ERM removal in 30 eyes, but not in the other 30 eyes. Age was significantly higher (P = 0.017) and the width of the ERM-ILM gap was significantly smaller (P < 0.001) in the simultaneous ILM peeling (+) group than in the simultaneous ILM peeling (-) group. Multivariate logistic regression analysis confirmed the width of the ERM-ILM gap as a significant negative predictor for simultaneous ILM peeling (odds ratio, 0.992; 95% confidence interval, 0.986-0.997; P = 0.003). Receiver operating characteristic curve analysis of the width of the ERM-ILM gap revealed that the optimal cutoff for predicting simultaneous ILM peeling was 187.1 µm. CONCLUSION: The small width of the ERM-ILM gap at the initiation site of ERM removal was significantly associated with simultaneous ILM peeling, indicating that the adhesion strength between the ERM and ILM at the initial ERM grasping site determines whether simultaneous ILM peeling will occur during ERM removal.

Thoughts of young adults with Down syndrome.

PURPOSE: This study aimed to obtain information about the thoughts of young adults with Down syndrome through interviews of them. METHODS: The numbers of participants were 4 and 7 in order to group interviews and individual interviews. They were recruited through the local Association of Parents of Down syndrome. The study incorporated a qualitative descriptive exploratory design to clarify the actual conditions of the lives young adults with Down syndrome and their own thoughts. RESULTS: Through analysis, six themes emerged: 1) thoughts about work, 2) existence of friends, 3) how to spend leisure time, 4) meaning of disability, 5) relationships with people, and 6) future dreams. CONCLUSIONS: 1) Although young adults with Down syndrome are serious about their work, it is difficult for them to make friends at work. However, they recognized people at work as their comrades and were encouraged by being spoken to by these people. 2) Although they had few opportunities to engage in activities with their friends, they looked forward to the contact with their friends. 3) In their leisure time, they often spent time alone, listening to CDs, or watching YouTube. 4) Four of the participants knew that they had Down syndrome, but they did not deny that fact.

Protrusion of KCNJ13 Gene Knockout Retinal Pigment Epithelium Due to Oxidative Stress-Induced Cell Death.

Purpose: This study was performed to elucidate the mechanisms of morphological abnormalities in a Leber congenital amaurosis 16 (LCA16) cell model using KCNJ13 knockout (KO) retinal pigment epithelial cells derived from human iPS cells (hiPSC-RPE). Methods: In KCNJ13 KO and wild-type hiPSC-RPE cells, ZO-1 immunofluorescence was performed, and confocal images were captured. The area and perimeter of each cell were measured. To detect cell death, ethidium homodimer III (EthD-III) staining and LDH assay were used. Scanning electron microscopy (SEM) was used to observe the cell surface. The expression levels of oxidative stress-related genes were examined by quantitative PCR. To explore the effects of oxidative stress, tert-butyl hydroperoxide (t-BHP) was administered to the hiPSC-RPE cells. Cell viability was tested by MTS assay, whereas oxidative damage was monitored by oxidized (GSSG) and reduced glutathione levels. Results: The area and perimeter of KCNJ13-KO hiPSC-RPE cells were enlarged. EthD-III-positive cells were increased with more dead cells in the protruded region. The KO RPE had significantly higher LDH levels in the medium. SEM observations revealed aggregated cells having broken cell surfaces on the KO RPE sheet. The KCNJ13-deficient RPE showed increased expression levels of oxidative stress-related genes and total glutathione levels. Furthermore, t-BHP induced a significant increase in cell death and GSSG levels in the KO RPE. Conclusions: We suggest that in the absence of the Kir.7.1 potassium channel, human RPE cells are vulnerable to oxidative stress and ultimately die. The dying/dead cells form aggregates and protrude from the surviving KCNJ13-deficient RPE sheet.

Bilateral Blunt Ocular Trauma Caused by an Exercise Resistance Band during Muscle Building Exercise for Swimming.

An 18-year-old male high school student presented to our clinic with bilateral blunt ocular trauma caused by an exercise resistance band (ERB) during a muscle-building exercise. Best-corrected decimal visual acuities (BCVAs) for right and left eyes were light perception and 0.15, respectively. The right eye was operated 10 days after injury for persistent vitreous hemorrhage, and the left eye 5 months later because of macular hole onset. After 36 months, the right eye showed extensive retinal degeneration (BCVA 0.04), and the left eye macular hole closure (BCVA 1.2). ERBs should be used cautiously as they can cause serious ocular trauma.

OBJECTIVE AND QUANTITATIVE ESTIMATION OF THE OPTIMAL TIMING FOR EPIRETINAL MEMBRANE SURGERY ON THE BASIS OF METAMORPHOPSIA.

PURPOSE: To establish an objective and quantitative biomarker of metamorphopsia in epiretinal membranes (ERMs) and determine the optimal timing for ERM surgery. METHODS: Retrospectively, 172 eyes with ERM were reviewed. Retinal folds because of tangential traction by ERM were visualized by en-face optical coherence tomography. The maximum depth of retinal folds (MDRF) within the parafovea was quantified. Metamorphopsia was quantified by M-CHARTS. The change in the distance between the retinal vessels after ERM surgery and the preoperative total depth of retinal folds between the vessels were quantified using en-face optical coherence tomography and optical coherence tomography angiography. RESULTS: Significant correlations were observed between preoperative MDRF and M-CHARTS scores before and at 6 months after surgery (r = 0.617 and 0.460, respectively; P < 0.001) and change in the distance between the retinal vessels after ERM surgery and preoperative total depth of retinal folds between the vessels (r = 0.471; P = 0.013). The preoperative MDRF values at which M-CHARTS scores were 0.5 before and 6 months after the surgery were 69 µm and 118 µm, respectively. CONCLUSION: The MDRF is an objective and quantitative biomarker of metamorphopsia in ERM. To maintain patients' quality of vision, ERM surgery may be performed when the preoperative MDRF ranges between 69 µm and 118 µm.

A Redox-Active Microporous Organosiloxane Containing a Stable Neutral Radical, Trioxotriangulene.

A new silyl-substituted trioxotriangulene (TOT) neutral radical and corresponding porous organosiloxanes (POSs) were synthesized. The neutral radical exhibited a peculiarly high stability and formed a diamagnetic π-dimer characteristic to TOT neutral radicals stabilized by the strong multiple SOMO-SOMO interaction in both solution and solid states. POSs including TOT units within the organosiloxane-wall were prepared by polycondensation of the silyl groups and formed microporous structures with ∼1 nm-size diameters. Redox ability of TOT units in the POS was demonstrated by the treatment of oxidant/reductant in heterogeneous suspension condition, where the TOT units were reversibly converted between reduced and neutral radical species. Furthermore, the solid-state electrochemical measurements of the POS revealed the reversible multi-stage redox ability of TOT units involving polyanionic species within the organosiloxane-wall.

Sublingual Gland Carcinoma Revealed by Choroidal Metastasis.

A 65-year-old man presented with a 1-week history of left eye distortion. An elevated choroidal lesion covering 6 disc diameters was found in the posterior retina of the left eye. Systemic examination revealed sublingual gland carcinoma and multiple lung metastases, and the diagnosis was choroidal metastasis from sublingual gland carcinoma. Following chemotherapy and radiation therapy, the choroidal lesion shrunk and the patient's visual acuity improved. The patient died 23 months after his first visit. To the best of our knowledge, this is the first reported case of choroidal metastasis from sublingual gland carcinoma.

Cytotoxic effects of alteplase, a recombinant tissue plasminogen activator, on human retinal pigment epithelial cells.

PURPOSE: To evaluate the cytotoxic effects of alteplase, a recombinant tissue plasminogen activator, and its additives on human retinal pigment epithelial (hRPE) cells. STUDY DESIGN: Laboratory study. METHODS: We evaluated the cytotoxic effects of alteplase on human fetal RPE (hfRPE) cells, human induced pluripotent stem cell-derived RPE (hiPS-RPE), and ARPE-19 cells, as well as the cytotoxic effects of L-arginine and polysorbate 80, two additives of alteplase, on hfRPE cells. The effects of alteplase on the production of vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) from hfRPE cells and the transepithelial resistance (TER) of hiPS-RPE cells were also assessed. The type of cell death induced by alteplase was investigated using ethidium homodimer III and FITC-Annexin V staining and terminal transferase deoxyuridine triphosphatase nick-end labeling. RESULTS: Alteplase reduced the viability of hfRPE cells significantly in a dose- and time-dependent manner. The reaction of hiPS-RPE and ARPE19 cells to alteplase was similar to that of hfRPE cells. Out of L-arginine and polysorbate 80, only treatment with L-arginine significantly reduced the viability of hfRPE cells. Alteplase (83 µg/ml, 6 h) had no significant effect on the production of VEGF and PEDF from hfRPE cells. Alteplase decreased the TER of hiPS-RPE cells in a dose- and time-dependent manner and induced necrosis as the type of cell death. CONCLUSION: Alteplase can be cytotoxic to human RPE cells in a concentration- and time-dependent manner, with L-arginine being a possible causative factor.

Embedding of Epiretinal Proliferation for a Secondary Lamellar Macular Hole 12 Years after Rhegmatogenous Retinal Detachment Repair.

A 58-year-old Japanese man underwent vitrectomy for rhegmatogenous retinal detachment (RRD) in 2002. Twelve years later, optical coherence tomography revealed the development of a lamellar macular hole; the visual acuity was 20/200. Two years later, because metamorphopsia and the foveal retina thinning were aggravated, epiretinal proliferation embedding was performed to restore the foveal structure by transplanting glial cells to the foveal cavity. The patient was followed-up for 4 years, and his macular morphology and visual acuity (20/66) improved. No complications occurred. This appears to be the first report of epiretinal proliferation embedding for a lamellar macular hole post-RRD repair.

Aurophilic Interactions in Multi-Radical Species: Electronic-Spin and Redox Properties of Bis- and Tris-[(Nitronyl Nitroxide)-Gold(I)] Complexes with Phosphine-Ligand Scaffolds.

Multinuclear AuI complexes with two or three nitronyl nitroxide-2-ide radical anion and phosphine-ligand scaffolds, (NN-Au)2 -1 o, (NN-Au)2 -1 m, and (NN-Au)2 -1 p, have been synthesized to investigate the influence of AuI -AuI (aurophilic) interactions on the properties of multispin molecular systems. The desired complexes were successfully prepared in moderate yields in a one-pot synthesis from the corresponding phosphine ligand, AuI source, parent NN, and sodium hydroxide. Among the prepared complexes, (NN-Au)2 -1 o, in which an aurophilic interaction was clearly observed by crystal structure analysis, showed characteristic spin-spin interactions, electrochemical properties, and solvatochromic behavior. The results from theoretical calculations also suggested that the differences in properties between complex (NN-Au)2 -1 o and the other complexes are due to intramolecular aurophilic interactions.