14 research outputs found

    Implementable deep learning for multi-sequence proton MRI lung segmentation: a multi-center, multi-vendor, and multi-disease study

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    Background Recently, deep learning via convolutional neural networks (CNNs) has largely superseded conventional methods for proton (1H)-MRI lung segmentation. However, previous deep learning studies have utilized single-center data and limited acquisition parameters. Purpose Develop a generalizable CNN for lung segmentation in 1H-MRI, robust to pathology, acquisition protocol, vendor, and center. Study type Retrospective. Population A total of 809 1H-MRI scans from 258 participants with various pulmonary pathologies (median age (range): 57 (6–85); 42% females) and 31 healthy participants (median age (range): 34 (23–76); 34% females) that were split into training (593 scans (74%); 157 participants (55%)), testing (50 scans (6%); 50 participants (17%)) and external validation (164 scans (20%); 82 participants (28%)) sets. Field Strength/Sequence 1.5-T and 3-T/3D spoiled-gradient recalled and ultrashort echo-time 1H-MRI. Assessment 2D and 3D CNNs, trained on single-center, multi-sequence data, and the conventional spatial fuzzy c-means (SFCM) method were compared to manually delineated expert segmentations. Each method was validated on external data originating from several centers. Dice similarity coefficient (DSC), average boundary Hausdorff distance (Average HD), and relative error (XOR) metrics to assess segmentation performance. Statistical Tests Kruskal–Wallis tests assessed significances of differences between acquisitions in the testing set. Friedman tests with post hoc multiple comparisons assessed differences between the 2D CNN, 3D CNN, and SFCM. Bland–Altman analyses assessed agreement with manually derived lung volumes. A P value of <0.05 was considered statistically significant. Results The 3D CNN significantly outperformed its 2D analog and SFCM, yielding a median (range) DSC of 0.961 (0.880–0.987), Average HD of 1.63 mm (0.65–5.45) and XOR of 0.079 (0.025–0.240) on the testing set and a DSC of 0.973 (0.866–0.987), Average HD of 1.11 mm (0.47–8.13) and XOR of 0.054 (0.026–0.255) on external validation data. Data Conclusion The 3D CNN generated accurate 1H-MRI lung segmentations on a heterogenous dataset, demonstrating robustness to disease pathology, sequence, vendor, and center. Evidence Level 4. Technical Efficacy Stage 1

    Surveillance of glaucoma medical therapy in a Glasgow teaching hospital: 26 years' experience

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    Aims: To report the initial findings of a unique database of 956 patients with ocular hypertension (OHT), normal tension glaucoma (NTG) and primary open angle glaucoma (POAG) attending the Glaucoma Clinic at Glasgow Royal Infirmary, Glasgow, UK. Method: The database contains retrospective data from 1981 and prospective data from 1999. Analyses have been carried out using specially written queries to generate reports relating to prescription trends and reasons for treatment discontinuation. Results: The database included the following numbers of patients: POAG 580; OHT 242; NTG 134. Of 2928 treatment-change episodes recorded, failure to reach or maintain a target intraocular pressure (IOP) accounted for 51.9%, while adverse effects accounted for 22.1%. Use of latanoprost has increased sharply since 1996, and that of brimonidine, betaxolol and dorzolamide has declined significantly. Bimatoprost had a higher rate of discontinuation due to adverse effects (25%) than travoprost (16.3%) or latanoprost (12.4%), but this was only statistically significant between latanoprost and bimatoprost (p = 0.0038). In 2000 the database informed the introduction of a new treatment protocol that resulted in a fall in discontinuations due to adverse effects by almost two-thirds. Conclusion: A large and unique treatment database has been established at the Glaucoma Clinic of Glasgow Royal Infirmary. Containing data spanning a 26-year period, it promises to be an invaluable resource for audit and research. It has already demonstrated its worth by informing changes in prescribing practice that have resulted in direct patient benefit

    Fibrosing Blepharo-conjunctivitis following Pyogenic Granuloma in Ocular Acne Rosacea

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    Purpose: To report a case of pyogenic granuloma associated with ocular acne rosacea. Design: Case report. Methods: Interventional case report. Results: The patient developed an unusual lesion of the conjunctiva and limbus, histologically confirmed to be pyogenic granuloma. Excision of the lesion resulted in symblepharon formation, adhesions between lid margins, tarsal conjunctiva, and cornea, and reductions in visual acuity. The patient underwent surgical separation of the corneal lid adhesions with a mucosal autograft for the tarsal conjunctiva and an amniotic membrane graft for the cornea with good results. Conclusions: Ocular rosacea is a common condition but such excessive and unusual fibrotic healing responses following excision of pyogenic granulomas have not been previously reported. This case demonstrated significant morbidity and decreased visual acuity. However, early recognition and effective surgical management can lead to good visual outcomes

    Economics of fertilizer use in the Maize-Mungbean/Dhaincha-T.aman rice cropping pattern

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    Field experiments were conducted over three years during 2001-2004 and 2002-2005 at BAU farm, Mymensingh and OFRD farm, Rangpur, respectively, using farm yard manure (FYM), dhaincha (Sesbania) and mungbean residue along with inorganic fertilizers. For the first crop (maize), there were five treatments i.e. T1: Control, T2: Moderate Yield Goal (MYG), T3: High Yield Goal (HYG), T4: FYM 5t/ha + Inorganic fertilizer for MYG as IPNS basis, T5: FYM 5t/ha + Inorganic fertilizer for HYG as IPNS basis. Each year, FYM was applied to maize crop and GM/MBR was applied before transplanting of aman rice. Integrated use of manure and inorganic fertilizers (IPNS basis) produced comparable seed yield of maize with the chemical fertilizers alone irrespective of moderate or high, yield goal basis (MYG or HYG) in both locations. After harvest of maize, mungbean and dhaincha (Sesbania) seeds were sown as per treatments. For T. aman rice (third crop), each of the plots of T2 and T3 treatments were subdivided into six, so there were altogether 15 treatments. At both locations, the incorporation of Sesbania biomass and mungbean residue along with inorganic fertilizers for MYG gave identical grain yields of T. aman rice with the fertilizers alone applied for HYG. There was an inverse relationship between the higher dose of fertilizer application and marginal benefit cost ratio (MBCR) at both the locations. Considering gross margin and marginal benefit-cost ratio (MBCR), legume residue incorporation along with inorganic fertilizers (IPNS basis) was found to be the best treatment (T3.3.3)

    Direct healthcare costs of glaucoma treatment

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    &lt;p&gt;Aims: To report the complete lifetime direct healthcare costs of glaucoma treatment in a database of 1136 patients attending the Glaucoma Clinic at Glasgow Royal Infirmary, Glasgow, UK.&lt;/p&gt; &lt;p&gt;Method: The database was interrogated to identify all patients who had initiated treatment at the Glaucoma Clinic at Glasgow Royal Infirmary, and who had subsequently died of natural causes. The healthcare resource use based cost assessment was based on two aspects of the direct National Health Service cost: drug costs (prescribed medications) and non-drug costs (inpatient or outpatient/and surgical or procedure costs).&lt;/p&gt; &lt;p&gt;Results: 106 patients (53 men, 53 women) were identified for whom there were lifetime treatment data. The mean lifespan of the patients was 80.5 years, and the mean number of years attending the glaucoma clinic was 7.05 years (range 1–22 years). The mean cost of glaucoma treatment over the lifetime of the patients was £3001, with an annual mean cost per patient of £475. Non-drug and drug costs made up 66% and 34% respectively, of the lifetime costs.&lt;/p&gt; &lt;p&gt;Conclusions: This is the only study to directly assess the lifetime treatment costs of glaucoma. Awareness of the costs of glaucoma treatment may be of increased importance in these financially challenging times.&lt;/p&gt

    Pure antimony film as saturable absorber for Q-switched erbium-doped fiber laser

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    This paper reports on the use of Antimony (Sb) polymer film to generate stable Q-switching pulses in Erbium-doped fiber laser (EDFL) cavity. The SA is fabricated by coating a thin layer of Sb on a polyvinyl alcohol (PVA) film through physical vapour deposition (PVD) process. A 1 × 1 mm area of the film SA is cut and integrated into between two fiber ferrules inside the laser cavity for intra-cavity loss modulation. Self-starting and stable Q-switched pulses are obtained within a pump power range from 60 to 142 mW. Within this range, the repetition rate increases from 70.82 to 98.04 kHz, while pulse width decreases from 7.42 to 5.36 μs. The fundamental frequency signal-to-noise ratio of the pulse signal is 74 dB, which indicates the excellent stability of the pulses. The maximum output power and pulse energy are 8.45 mW and 86.19 nJ, respectively. Our demonstration shows that Sb film SA capable of generating stable pulses train operating at 1.55-micron region
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