A Prototype of a Stereoacuity Test Using a Head-Mounted Display

Purpose@#To evaluate the test-retest reliability of a contour-based stereoacuity test using a head-mounted display (HMD) and compare it with other stereotests. @*Methods@#Thirty-two healthy adults aged 23-47 years were recruited from a tertiary hospital between August 2017 and July 2018. Two separate contour-based circles (crossed disparity: 135-1,350 arcsecs) were generated on a high-resolution phone display (Galaxy S7; Samsung, Seoul, Korea) using an HMD (Galaxy Gear VR). Two images were independently projected to each eye as graded circles with a random dot background. The results of the new HMD stereotest were compared to those of the standard Randot and TNO stereotests. The test-retest reliability was assessed using the Bland-Altman plot and Cohen’s kappa statistics. @*Results@#Among the 32 study participants, 17 (53%) were males and the mean age was 30.1 ± 4.8 years (range: 23-47). The mean stereoacuity was 160.3 ± 53.5 arcsecs in the first HMD stereotest (HMD1), 28.4 ± 12.5 arcsecs in the Randot stereotest, 96.1 ± 83.5 arcsecs in the TNO stereotest, and 143.3 ± 47.7 arcsecs in the second HMD stereotest (HMD2). The Bland-Altman plot showed a mean difference of 0.042 (-0.189 to +0.272, 95% limits of agreement) between HMD1 and HMD2. The reliability analysis showed an intraclass correlation coefficient of 0.499 (p = 0.022) and agreement of 81.25% in Cohen’s kappa statistics (Cohen’s kappa index = 0.119, p = 0.017). @*Conclusions@#The HMD stereotest without monocular cues showed fair test-retest reliability and reproducibility. Further studies using a high resolution display are needed to confirm the validity of the HMD stereotest.

Relationship between Ocular Fatigue and Use of a Virtual Reality Device

PURPOSE: To investigate ocular fatigue after the use of a head-mounted display (HMD)-type virtual reality device.METHODS: Healthy adult volunteers were examined for ocular fatigue before and after watching videos for 10 min with an HMD-type virtual reality device. Subjective ocular fatigue was measured using a questionnaire. Objective fatigue was measured using the critical flicker fusion frequency (CFF), high frequency component of accommodative microfluctuation, and accommodation amplitude. The accommodation amplitude was measured using the push-up method and the dynamic measurement mode of the autorefractometer. Changes in the spherical equivalent were also measured.RESULTS: The questionnaire-based subjective ocular fatigue increased (p = 0.020) after use of the HMD device. In the dominant eye, the high frequency component of accommodative microfluctuation increased (p < 0.05). The accommodation amplitude using the push-up method was decreased in the nondominant eye (p = 0.007), and temporary myopia was observed (p < 0.05). However, there was no increase in ocular fatigue in the CFF or the accommodation amplitude using the dynamic measurement mode, which showed no significant difference before and after using the HMD device (p > 0.05).CONCLUSIONS: A subjective test and some objective tests suggested that use of the HMD-type virtual reality display increased ocular fatigue. However, no increase in ocular fatigue was measured using CFF nor in the accommodation amplitude using the dynamic measurement mode which was a limitation of the study. More studies with the aim to alleviate ocular fatigue after using HMD-type virtual reality devices are therefore needed.

Clinicopathologic Features of Pleomorphic Invasive Lobular Carcinoma: Comparison with Classic Invasive Lobular Carcinoma

PURPOSE: The purpose of this study was to identify the clinical and pathological factors that differentiate pleomorphic invasive lobular carcinoma (PILC) from classic invasive lobular carcinoma (CILC). METHODS: We retrospectively reviewed the medical records of 65 patients (4.0% of all invasive breast cancer patients) who underwent surgical excision for invasive lobular carcinoma (ILC) between January 2000 and November 2013. All 65 patients were diagnosed with ILC with negative immunohistochemical staining for E-cadherin in the tumor cells. All hematoxylin and eosin slides of the previously diagnosed ILC were reviewed and confirmed by two expert pathologists and we compared the clinicopathologic features between CILC and PILC. RESULTS: CILC was found in 46 cases and PILC, in 19 cases. Of the mammographic findings, a mass or asymmetric density was the most common feature (42.3% of all ILC patients). The most common ultrasonographic feature was a mass (94.9% of all ILC patients). Tumor multiplicity was noted in 10 patients (15.4%) among all ILC patients; eight patients (17.4%) had CILC and two patients (10.5%) had PILC. PILC patients had more grade III tumors (66.7% vs. 8.7%, p=0.002) and a higher Ki-67 labeling index (55.6% vs. 18.6%, p=0.004) than those with CILC. There were no statistical differences in the type of combined in situ component, extensive intraductal component, tumor size, lymphovascular invasion, stage, hormone receptor status, human epidermal growth factor receptor 2 status, distribution of intrinsic subtype, or imaging findings. Moreover, there was no significant difference in survival between CILC and PILC. CONCLUSION: PILC showed more pathological aggressiveness than CILC in terms of tumor grade and Ki-67 index.

The Results of Occult Breast Carcinoma Treated with Axillary Node Dissection Only: Five Cases Reports

Herein, we report five cases of occult breast cancer treated with axillary node dissection only, without breast surgery or whole breast radio-therapy. The patients complained of a large, hard mass in the axillary area, although no breast masses were palpable. Biopsy of the axillary mass was performed in each case, and histological examination showed a metastatic carcinoma. No malignant findings were observed by mammography or ultrasonography. Magnetic resonance imaging and systemic examinations revealed no extramammary primary lesions. All patients underwent axillary lymph node dissection without breast surgery, and were administered adjuvant chemotherapy but not whole breast radiation therapy. The median follow-up period was 56 months (range, 15–241 months). The patients were all alive with no evidence of disease at the end of the follow-up period.

Biologic subtype is a more important prognostic factor than nodal involvement in patients with stages I and II breast carcinoma

PURPOSE: Nodal infiltration has been one of the most important prognostic factors in breast cancer. In recent decades, risk stratification has greatly changed, and is applied in accordance with hormone receptor and human epidermal growth factor receptor 2 (HER2) status. We compared the prognostic power of tumor subtype to nodal involvement in early breast cancer. METHODS: We reviewed the medical records of 505 patients who had curative surgery for stage I or II breast cancer. We analyzed clinicopathologic factors according to tumor subtype and nodal involvement. Tumors were classified into 4 subtypes according to immunohistochemical status of estrogen receptor, progesterone receptor, HER2, and Ki67 labeling index. Disease-free survival (DFS) and overall survival were analyzed. RESULTS: There were 363 node-negative patients (71.9%) and 142 node-positive patients (28.1%). Luminal A, Luminal B, HER2, and triple-negative breast cancer subtypes were composed of 207 (41.0%), 147 (29.1%), 42 (8.3%), and 109 patients (21.6%), respectively. The median follow-up period was 89.5 months. Node negative-luminal A subtype showed the best prognosis with regard to 5-year DFS, and the pN1-triple negative subtype was associated with the shortest DFS (95.1% vs. 67.8%; hazard ratio, 9.554; P < 0.001). However, the node negative-triple negative subtype was associated with a worse 5-year DFS than the pN1-luminal A subtype ([86.4%; hazard ratio, 2.647; P = 0.048] vs. [93.2%; hazard ratio, 2.061; P = 0.194]). CONCLUSION: Node negative-triple negative breast cancer was associated with a poorer prognosis than pN1-luminal A subtype. Tumor subtype has greater prognostic power compared to nodal status in early breast cancer.

Combined chemotherapy and intra-arterial chemotherapy of retinoblastoma / 소아과

PURPOSE: Retinoblastoma (RB) is the most common primary malignant intraocular tumor in children. Although systemic chemotherapy has been the primary treatment, intra-arterial chemotherapy (IAC) represents a new treatment option. Here, we performed alternate systemic chemotherapy and IAC and retrospectively reviewed the efficacy and safety of this approach. METHODS: Patients diagnosed with intraocular RB between January 2000 and December 2011 at Severance Children's Hospital, Yonsei University, were reviewed. Before February 2010, the primary treatment for RB was chemotherapy (non-IAC/CTX). Since February 2010, the primary treatment for RB has been IAC (IAC/CTX). External beam radiotherapy or high-dose chemotherapy were used as "last resort" treatments just prior to enucleation at the time of progression or recurrence during primary treatment. Enucleation-free survival (EFS) and progression-free survival were assessed. RESULTS: We examined 19 patients (median age, 11.9 months; range, 1.4 to 75.6 months) with a sum of 25 eyes, of which, 60.0% were at advanced Reese Ellsworth (RE) stages. The enucleation rate was 33.3% at early RE stages and 81.8% at advanced RE stages (P=0.028). At 36 months, EFS was significantly higher in the IAC/CTX group than in the non-IAC/CTX group (100% vs. 40.0%, P=0.016). All 5 patients treated with IAC achieved eye preservation, although most patients were at advanced RE stages (IV-V). CONCLUSION: Despite the limitation of a small sample size, our work shows that an alternative combined approach using IAC and CTX may be safe and effective for eye preservation in advanced RB.