Machine learning, classification of 3D UAV-SFM point clouds in the University of KwaZulu-Natal (Howard College)

Masters Degrees. University of KwaZulu- Natal, Durban.Three-dimensional (3D) point clouds derived using cost-effective and time-efficient photogrammetric technologies can provide information that can be utilized for decision-making in engineering, built environment and other related fields. This study focuses on the use of machine learning to automate the classification of points in a heterogeneous 3D scene situated in the University of KwaZulu-Natal, Howard College Campus sports field. The state of the camera mounted on the unmanned aerial vehicle (UAV) was evaluated through the process of camera calibration. Nadir aerial images captured using a UAV were used to generate a 3D point cloud employing the structure-from-motion (SfM) photogrammetric technique. The generated point cloud was georeferenced using natural ground control points (GCPs). Supervised and unsupervised classification approaches were used to classify points into three classes: ground, high vegetation and building. The supervised classification algorithm used a multi-scale dimensionality analysis to classify points. A georeferenced orthomosaic was used to generate random points for cross-validation. The accuracy of classification was evaluated, employing both qualitative and quantitative analysis. The camera calibration results showed negligible discrepancies when a comparison was made between the results obtained and the manufacturer’s specifications in parameters of the camera lens; hence the camera was in the excellent state of being used as a measuring device. Site visits and ground truth surveys were conducted to validate the classified point cloud. An overall root-mean-square (RMS) error of 0.053m was achieved from georeferencing the 3D point cloud. A root-mean-square error of 0.032m was achieved from georeferencing the orthomosaic. The multi-scale dimensionality analysis classified a point cloud and achieved an accuracy of 81.3% and a Kappa coefficient of 0.70. Good results were also achieved from the qualitative analysis. The classification results obtained indicated that a 3D heterogeneous scene can be classified into different land cover categories. These results show that the classification of 3D UAV-SfM point clouds provides a helpful tool for mapping and monitoring complex 3D environments

Anatomical variation of the Dorsalis pedis artery in a South African population- A Cadaveric Study

Abstract: The dorsalis pedis artery is responsible for blood supply to the dorsal aspect of the foot and is vital in the clinical assessment of the arterial supply thereof. Clinical assessment should consider anatomical variations of dorsalis pedis artery. Clearly, a thorough understanding of the potential variations of the vasculature in the area is important for a precise clinical assessment of arterial supply to the foot. The aim of this study was to investigate the different branching patterns of the dorsalis pedis artery that exist in a South African population. Methods: A Cadaveric study in which a total of 33 dissected lower limbs (27 adult cadavers and 6 partial wet lower limb specimens) of a South African population sample were studied. The course and branching pattern of the dorsalis pedis artery were photographed and documented. Results: Nine variations of the dorsalis pedis artery were recorded, with the standard branching pattern being the most common with an incidence of 36.36% and a completely absent dorsalis pedis artery variation was noted in 6.06% of the sample. Conclusion: Nine variations of the arterial anatomy of the dorsalis pedis artery were identified in this current study. Each of these may possibly alter the location or strength of the dorsalis pedis pulse affecting clinical assessment outcomes. Knowledge of dorsalis pedis variations may be useful to clinicians when making clinical decisions

Risk factors for diabetic foot ulceration in diabetic patients presenting at primary healthcare clinics in South Africa

Abstract: Objective: The main purpose of the study was to investigate the need for podiatrists as members of the primary healthcare team. One of the objectives of the study was to determine the percentage of patients presenting at the two Primary Healthcare clinics who are at risk of developing foot complications as a result of an underlying concomitant systemic disease. Research design and methods: A descriptive cross-sectional study in which data was collected from patients presenting at two homogeneously selected Primary Healthcare (PHC) clinics in Johannesburg. Nursing staff assisted by a final year podiatry student collected data using a self-constructed data collection form (DCF) from each consenting patients as part of their routine patient consultation. Simple descriptive statistics were used for data analysis. Results: Data was collected and analysed from 1077 patients and showed that 29% of the patients had diabetes. Diabetic foot ulceration risk factors that were recorded included peripheral neuropathy in 74% of diabetic patients, structural foot deformities in 47%, peripheral vascular symptoms in 39% and foot ulcer in 28% of the diabetic patients. Conclusion: Early identification of diabetic patients who are at high risk of diabetic foot ulceration is important and can be achieved via a mandatory diabetic foot screening with subsequent multidisciplinary foot-care interventions. Understanding the factors that place patients with diabetes at high risk of ulceration, together with an appreciation of the links between different aspects of the disease process and foot function, is essential to the prevention and management of diabetic foot complications. Significance of the study • There is limited data available on diabetic foot risk factors across all levels of care in South Africa. • The study found that up to 74% of patients presenting at PHC facilities in this study had symptoms of diabetic peripheral neuropathy and 28% had foot ulcers. • The findings are suggestive of a need for diabetic foot assessment to be mandated at PHC level as part of the routine diabetic patient assessment and for Podiatrists to be involved at this level of care

South African podiatry students’ perceptions of feedback given as part of clinical training

Abstract: As part of their clinical training podiatry students spend time in clinical settings treating patients under the supervision of qualified podiatrists. The role and purpose of feedback during such clinical training is to improve students’ knowledge, skills and behaviour. Feedback is an integral part of the learning process that should enhance students’ clinical learning experiences. However, there is no data on podiatry students’ satisfaction or lack thereof about feedback provided during clinical training. The aim of this study was to determine the perceptions of podiatry students on feedback given or received during clinical training..

The need for podiatrists as members of the primary health care team

Abstract: BACKGROUND- In South Africa (SA), Primary Health Care (PHC) forms the basis for health service delivery. As such, Primary Health Care Clinics PHCCs) remain the first point of contact for the majority South Africans accessing public health services. Whilst many of these PHC clinics have been established within communities and regions in Gauteng, few include Podiatrists as part of their staff compliments. METHODS- This prospective mixed-method study investigated the need for, and potential role of, Podiatrists as members of the PHC team. Quantitative data were collected and analysed from a sample of 1077 patients presenting for routine consultation at two local PHC Clinics, and qualitative data were gathered from the focus group discussion held with nurses from the two clinics. RESULTS- The results highlighted that as much as 18% of patients presenting to these clinics had a chief pathology related to the foot or lower limb. Furthermore, a significant number of patients with common systemic disorders such as diabetes, hypertension and arthritis were noted to also have concomitant foot pathologies. Focus group discussions held with primary health care nurses highlighted significant challenges relating to management of foot complaints, these included problems with referral pathways and a lack of training, confidence and time to effectively assess their patient’s feet...M.Tech. (Podiatry