Unraveling False Positives in Unsupervised Defect Detection Models: A Study on Anomaly-Free Training Datasets.

Unsupervised defect detection methods have garnered substantial attention in industrial defect detection owing to their capacity to circumvent complex fault sample collection. However, these models grapple with establishing a robust boundary between normal and abnormal conditions in intricate scenarios, leading to a heightened frequency of false-positive predictions. Spurious alerts exacerbate the work of reconfirmation and impede the widespread adoption of unsupervised anomaly detection models in industrial applications. To this end, we delve into the sole available data source in unsupervised defect detection models, the unsupervised training dataset, to introduce a solution called the False Alarm Identification (FAI) method aimed at learning the distribution of potential false alarms using anomaly-free images. It exploits a multi-layer perceptron to capture the semantic information of potential false alarms from a detector trained on anomaly-free training images at the object level. During the testing phase, the FAI model operates as a post-processing module applied after the baseline detection algorithm. The FAI algorithm determines whether each positive patch predicted by the normalizing flow algorithm is a false alarm by its semantic features. When a positive prediction is identified as a false alarm, the corresponding pixel-wise predictions are set to negative. The effectiveness of the FAI method is demonstrated by two state-of-the-art normalizing flow algorithms on extensive industrial applications.

[Glaucomatous visual field loss in eyes undergoing first trabeculectomy in Iceland]. / Sjónsviðsskerðing við fyrstu hjáveituaðgerð (trabeculectomiu) vegna gláku

INTRODUCTION: Glaucoma is a degenerative disease in the optic nerve with associated visual field defects (VFD). Trabeculectomy is the most common glaucoma surgery. Surgery is indicated if glaucomatous optic neuropathy progresses despite tolerated medical treatment or in patients with severe VFD. The purpose of this paper is to describe the severity of visual field damage in patients undergoing their first trabeculectomy in Iceland. METHODS: A retrospective review of medical records of all patients with open angle glaucoma that underwent first trabeculectomy at Landspítali University Hospital, from June 2013 to March 2016. Visual fields were examined by Octopus automated perimetry and the severity of glaucoma damage was staged according to the mean defect (MD). RESULTS: 86 eyes were included in the study, mean age 75 ± 11 years, 57% men. Patients used on average three IOP lowering medications. Mean MD at referral to surgery was 13.4 ± 7.7dB (min 0.8dB, max 26.2 dB), 21% had early glaucomatous damage (MD <6dB), 23% moderate (MD 6-12 dB) and 56% severe (MD > 12). CONCLUSION: VFD at referral to surgery varied from mild VFD to severe damage. Like clinical guidelines recommend, treatment seems to be individualized and the most common indication for surgery was increased VFD despite medical treatment. Mean MD at referral to surgery was high compared to other studies. Eyes with severe VFD had on average lower IOP and thinner cornea. This might indicate that great emphasis is placed on high IOP and perhaps too little emphasis on VFD and cornea thickness.

Porphyromonas gingivalis causing brain abscess in patient with recurrent periodontitis.

We report an extremely rare case of Porphyromonas gingivalis causing brain abscess in a patient with recurrent periodontitis. The patient presented with right-sided homonymous hemianopsia and right hemiparesis. Emergent surgical drainage was performed and antibiotics were administered. P. gingivalis was identified from the anaerobic culture of the abscess. The clinical course of the patient improved with full recovery of the neurologic deficit.

Visual Impairment Due to Lissencephaly.

Lissencephaly is a rare disorder due to abnormal neural migration, causing neurological impairment and clinically characterised by mental retardation and epilepsy. Any disturbance of the visual pathway can cause loss of vision. The authors describe a case of a 6-year-old boy referred to the ophthalmologist presenting poor bilateral vision. This child had no other known medical conditions, and neurological examination was completely normal. Only when a magnetic resonance imaging was made that a lissencephaly-pachygyria with band heterotopia mostly occipital was noted. Cortical defects should be considered in order to diagnosis some visual defects in children.

Optochiasmatic cavernoma: Surgical treatment and outcomes.

OBJECTIVE: Optochiasmatic cavernoma is an extremely rare cerebral lesion. They account for approximately 1% of all cavernomas of the central nervous system. Reports on this pathology are limited. Abrupt visual deterioration is a common symptom of the disease. Treatment strategy and visual outcomes after different treatment approaches remain a subject for discussion. METHODS: Patients operated in a period 2005-2021 were analyzed in this study. All patients preoperatively underwent computed tomography (CT) scan, CT-angiography, and magnetic resonance imaging (MRI). Visual function of the patients was assessed pre-op, post-op and at the follow-up. Duration of visual dysfunction was noted as well. Surgical details were also extracted from medical notes. All patients were followed up, and control MRI was performed one month after operation. We assessed surgical series of optochiasmatic cavernomas published for last 10 years. Further comparative analysis with our data was performed. RESULTS: Five patients were included into this study. There were four men and one woman. Mean age comprised 33.8 years (range 20-48 years). Most patients were admitted to our hospital due to visual disturbances (80%). Visual function improved in four patients. Visual function was unchanged in one patient, lacking visual disturbancies pre-op. Complication developed in one patient. CONCLUSIONS: Optochiasmatic cavernomas are encountered extremely rare. Despite the use of contemporary diagnostic options, differential diagnosis remains challenging. Full diagnostic work-up is mandatory. After the diagnosis is made, surgical treatment should be considered first. Total microsurgical or endoscopic transsphenoidal removal of the optochiasmatic cavernoma is a relatively safe and effective treatment method facilitating improvement of visual function.

Cotton stubble detection based on wavelet decomposition and texture features.

BACKGROUND: At present, the residual film pollution in cotton fields is crucial. The commonly used recycling method is the manual-driven recycling machine, which is heavy and time-consuming. The development of a visual navigation system for the recovery of residual film is conducive, in order to improve the work efficiency. The key technology in the visual navigation system is the cotton stubble detection. A successful cotton stubble detection can ensure the stability and reliability of the visual navigation system. METHODS: Firstly, it extracts the three types of texture features of GLCM, GLRLM and LBP, from the three types of images of stubbles, residual films and broken leaves between rows. It then builds three classifiers: Random Forest, Back Propagation Neural Network and Support Vector Machine in order to classify the sample images. Finally, the possibility of improving the classification accuracy using the texture features extracted from the wavelet decomposition coefficients, is discussed. RESULTS: The experiment proves that the GLCM texture feature of the original image has the best performance under the Back Propagation Neural Network classifier. As for the different wavelet bases, the vertical coefficient texture feature of coif3 wavelet decomposition, combined with the texture feature of the original image, is the feature having the best classification effect. Compared with the original image texture features, the classification accuracy is increased by 3.8%, the sensitivity is increased by 4.8%, and the specificity is increased by 1.2%. CONCLUSIONS: The algorithm can complete the task of stubble detection in different locations, different periods and abnormal driving conditions, which shows that the wavelet coefficient texture feature combined with the original image texture feature is a useful fusion feature for detecting stubble and can provide a reference for different crop stubble detection.

Suprasellar germinoma with hypopituitarism in an 18-year old man: A case report and review of literature.

An 18 year old patient was presented to the ophtalmology outpatient clinic with blurrred vision, headache and fatigue for 6 months. Ophtalmological examination showed loss of visual acuity in the left eye and decreased in the right eye and bilateral optic atrophy. Further physical examination pointed out delayed sexual development. Hypopituitarism was observed in endocrinological examination. Brain magnetic resonance imaging (MRI) demonstrated contrast enhancing mass lesion at suprasellar region with involvement of posterior perimesencephalic cisternal region. The mass resected by craniotomy and pathology showed germinoma. Afterwards he received systemic chemotherapy with bleomisin, etoposide, cisplatin for 4 cycles followed by cranial radiotherapy with 30.6 Gy with a boost to the primary tumor at a dose of 19.8 Gy. On his follow-up MRI, there are no signs of residual tumor nor tumor recurrence. His final examination reveals slightly increased visual acuity in the right eye and he continued to take hydrocortisone and L-thyroxin. After one year follow-up, human chorionic gonadotropin (hCG) alpha treatment was started for sexual development. Here in, we present a case with suprasellar germinoma in the context of the review of the literature.

Toxic Effects of Methanol among Illegally Dispatched Workers at Aluminum CNC Cutting Process in Small-Scale, Third-Tier Subcontractor Factories of Smartphone Manufacturers in the Republic of Korea.

An outbreak of occupational methanol poisoning occurred in small-scale, third-tier factories of large-scale smartphone manufacturers in the Republic of Korea in 2016. To investigate the working environment and the health effects of methanol exposure among co-workers in the methanol poisoning cases, we performed a cross-sectional study on 155 workers at five aluminum Computerized Numerical Control (CNC) cutting factories. Gas chromatography measured air and urinary methanol concentration. In the medical examination, symptom surveys, ophthalmological examinations, and neurobehavioral tests were done. Multiple logistic regression analyses controlling for age and sex were conducted to reveal the association of employment duration with symptoms. Air concentrations of methanol in factory A and E ranged from 228.5 to 2220.0 ppm. Mean urinary methanol concentrations of the workers in each factory were from 3.5 mg/L up to 91.2 mg/L. The odds ratios for symptoms of deteriorating vision and central nervous system (CNS) increased according to the employment duration after adjusting for age and sex. Four cases with an injured optic nerve and two cases with decreased neurobehavioral function were founded among co-workers of the victims. This study showed that the methanol exposure under poor environmental control not only produces eye and CNS symptoms but also affects neurobehavioral function and the optic nerve. The role of subcontracting production and dispatched work under poor environmental control was discussed.

Endoscopic Endonasal Transsphenoidal Treatment of Pituitary Apoplexy: Outcomes in a Series of 20 Patients.

OBJECTIVE: Pituitary apoplexy is a rare clinical entity and few cases treated with an endonasal endoscopic approach (EEA) have been reported. We report our experience of treating pituitary apoplexy using an EEA approach. METHODS: We performed a retrospective chart review on all the patients who underwent EEA skull base and pituitary surgery between December 2003 and March 2012 performed by the senior authors (THS and VKA) and identified patients with pituitary apoplexy. The extent of resection was determined volumetrically and the visual and endocrine outcome was evaluated.  RESULTS: From a total of 488 skull base surgeries, there were 241 pituitary cases, of which 20 had apoplexy. The most common presenting symptoms included headaches (80%), endocrinopathy (95%), and visual symptoms (60%). Surgery was performed within 24 hours in 15% of patients, and > one month after ictus in 40% due to late referral. Gross-total resection (GTR) was achieved in 18 (90%) patients. There was one (5%) postoperative cerebrospinal fluid (CSF) leak treated with lumbar drainage. Of 12 patients with preoperative visual disturbances, seven had improvements. For those patients with visual field cuts, only 33.3% showed improvement. There was no postoperative visual deterioration. Two patients developed new transient postoperative diabetes insipidus (DI) but there was no new permanent DI. The mean duration of follow-up was 22 months (range: 6 days - 72 months). CONCLUSION: The endoscopic endonasal transsphenoidal approach is an effective modality to treat pituitary apoplexy with a high rate of GTR and minimal risk. Delayed surgery may result in lower rates of visual field defect improvement.

A Large Ruptured Anterior Communicating Artery Aneurysm Presenting with Bitemporal Hemianopsia.

Anterior communicating artery (ACoA) aneurysms sometimes present with visual symptoms when they rupture or directly compress the optic nerve. Giant or large ACoA aneurysms producing bitemporal hemianopsia are extremely rare. Here we present an unusual case of bitemporal hemianopsia caused by a large intracranial aneurysm of the ACoA. A 41-year-old woman was admitted to our neurosurgical department with a sudden-onset bursting headache and visual impairment. On admission, her vision was decreased to finger counting at 30 cm in the left eye and 50 cm in the right eye, and a severe bitemporal hemianopsia was demonstrated on visual field testing. A brain computed tomography scan revealed a subarachnoid hemorrhage at the basal cistern, and conventional cerebral catheter angiography of the left internal carotid artery demonstrated an 18×8 mm dumbbell-shaped aneurysm at the ACoA. Microscopic aneurysmal clipping was performed. An ACoA aneurysm can produce visual field defects by compressing the optic chiasm or nerves. We emphasize that it is important to diagnose an aneurysm through cerebrovascular study to prevent confusing it with pituitary apoplexy.

Management of charles bonnet syndrome in the elderly.

The case of an 82 year old lady who suffered from vivid episodic complex visual pseudohallucination is presented. The alleviation of symptoms with carbamazepine monotherapy is highlighted. Correction of visual defect as another aspect of the management of Charles Bonnet syndrome in elderly patients is recommended.