Patrick Felle

Surgical e-learning: validation of multimedia web-based lectures

Background  Distance learning has been advocated increasingly as a modern efficient method of teaching surgery. Efficiency of knowledge transfer and validity of web‐based courses have not been subjected to rigorous study to date.

Prenatal treatment with retinoic acid promotes pulmonary alveologenesis in the nitrofen model of congenital diaphragmatic hernia

BACKGROUND/PURPOSE Severe pulmonary hypoplasia remains the main cause of the high mortality in newborn infants with congenital diaphragmatic hernia (CDH). Retinoids are a family of molecules derived from vitamin A, which play an important role in lung development. We hypothesized that retinoids promote alveologenesis at the end of gestation and therefore designed this study to investigate the effects of retinoid acid on nitrofen-induced hypoplastic lungs in CDH. METHODS Pregnant rats were exposed to either olive oil or 100 mg nitrofen on day 9 of gestation. Retinoic acid 5 mg/kg was given intraperitoneally on days 18, 19, and 20 of gestation and fetuses were recovered on day 21. We had 4 study groups: control (n = 24), control + retinoic acid (n = 22), CDH (n = 24), and CDH + retinoic acid (n = 19). Lungs from the 4 study groups were fixed, and the following stereological measurements were performed on vertical random sections: total lung volume, volume density of airspaces, volume density of air walls, gas exchange surface area, alveolar volume, and total number of alveoli per lung. Total DNA content of each lung was measured using a spectrophotometer. RESULTS Total lung volume increased in CDH lungs after the addition of retinoic acid but remained the same in the control group. Gas exchange surface area was larger in CDH lungs after the addition of retinoic acid but remained unchanged in the control group. The total number of alveoli per lung was higher after the addition of retinoic acid. Total DNA content as well as total DNA content-lung weight ratio of the left lung increased significantly in the CDH group after the addition of retinoic acid compared with CDH without retinoic acid. CONCLUSIONS Our results demonstrate that prenatal treatment with retinoic acid stimulates alveologenesis in hypoplastic lungs in CDH.

Stereology of the placenta in type 1 and type 2 diabetes.

OBJECTIVE To assess by stereology the placental structure in type 1 (T1DM) and type 2 (T2DM) diabetic pregnancies compared to normal non-diabetic (ND) controls. STUDY DESIGN Prospective case control study. Placentae were sampled in a systematic random fashion. Stereological analysis was performed using a computerised stereology programme (Image Pro 6.2, Media Cybernetics, Inc, Silver Spring MD, USA). Participants were matched for gender of infant and mode of delivery. MAIN OUTCOME MEASURES Volume, length and surface area of placental components; clinical outcome. RESULTS Ten ND, eight T2DM and ten T1DM women consented to the study. There was no difference between the groups regarding maternal age, neonatal birth weight, or placental weight. On stereological examination, terminal villous volume was significantly increased in both diabetic groups compared to ND controls. Capillary volume and length was increased in T1DM pregnancies compared to ND and T2DM. Capillary length was increased in both diabetic groups compared to ND. When all diabetic groups were compared based on severity of glycaemia those with poor glycaemic control (HbA1c>7%) had higher placental capillary volume than those with good glycaemic control. CONCLUSIONS This study demonstrates an association between maternal diabetes and increased terminal villous volume. Additionally capillary volume and length is increased in the placentae of normally grown infants of T1DM diabetic mothers compared to non-diabetic controls. Maternal glycaemia appears to influence capillary, but not stromal, development. This suggests that factors other than glycaemia have a role in placental development in pre-gestational diabetes.

Electronic learning can facilitate student performance in undergraduate surgical education: a prospective observational study

BackgroundOur institution recently introduced a novel internet accessible computer aided learning (iCAL) programme to complement existing surgical undergraduate teaching methods. On graduation of the first full cycle of undergraduate students to whom this resource was available we assessed the utility of this new teaching facility.MethodThe computer programme prospectively records usage of the system on an individual user basis. We evaluated the utilisation of the web-based programme and its impact on class ranking changes from an entry-test evaluation to an exit examination in surgery.Results74.4% of students were able to access iCAL from off-campus internet access. The majority of iCAL usage (64.6%) took place during working hours (08:00–18:00) with little usage on the weekend (21.1%). Working hours usage was positively associated with improvement in class rank (P = 0.025, n = 148) but out-of hours usage was not (P = 0.306). Usage during weekdays was associated with improved rank (P = 0.04), whereas weekend usage was not (P = 0.504). There were no significant differences in usage between genders (P = 0.3). Usage of the iCAL system was positively correlated with improvement in class rank from the entry to the exit examination (P = 0.046). Students with lower ranks on entry examination, were found to use the computer system more frequently (P = 0.01).ConclusionElectronic learning complements traditional teaching methods in undergraduate surgical teaching. Its is more frequently used by students achieving lower class ranking with traditional teaching methods, and this usage is associated with improvements in class ranking.

Patellofemoral contact forces and pressures during intramedullary tibial nailing

Summary. Patellofemoral joint forces and pressures were measured in a cadaver model during intramedullary nailing of the tibia. A significant increase in contact pressures was found at the lateral facet of the patellofemoral articulation using the medial paratendinous approach (P = 0.01) and at the medial facet when using the trans-patellar tendon approach (P = 0.001) to the proximal tibia. Increased contact pressures at the patellofemoral joint may result in chondral injury, which in turn may cause anterior knee pain, a common complication of tibial nailing.Résumé. Les auteurs ont mesuré les forces et les pressions de l’articulation fémoro-patellaire sur un modèle cadavérique au cours de l’enclouage intra-médullaire du tibia. Une augmentation notable de la pression au niveau de la facette latérale de la fémoro-patellaire a été mesurée lors de l’utilisation d’un abord paratendineux interne tandis qu’une augmentation de la pression au niveau de la facette médiane était notée lors de l’abord trans-tendineux de l’extrêmité supérieure du tibia (P = 0.01). Ces augmentations de pression au sein de l’articulation fémoro-patellaire peuvent aboutir à une lésion cartilagineuse pouvant provoquer des douleurs antérieures du genou, complication fréquente de l’enclouage tibial.

Attitudes of the medical profession to whole body and organ donation

Cadaveric dissection remains an important part of undergraduate medical education in anatomy. In a concerted effort to rise the number of doctors in practice in Ireland the amount of medical school placements has been increased steadily since 1995. This poses a problem as the number of cadavers has remained unchanged despite an overall increase in the population Ireland over the last twenty years. The medical profession plays a central part in raising public awareness of living and post-mortem organ donation. Previous studies have examined the attitudes of medical students to whole body donation, however to our knowledge this is the first study that evaluates the attitudes of medical professionals. We assess the opinions of junior and senior doctors at the time of their dissection experience and in their current practice. We show that their attitudes have changed as their clinical experience grows.

Differences between the Histology of Normal Spleen and That of Regenerated Ectopically Implanted Splenic Tissue

The histology of regenerated ectopically implanted spleen (splenotic tissue) from splenectomized rats was compared with that of normal rat spleen. Computer-assisted morphometric analysis revealed significant decreases in both the number and area of splenic nodules in splenotic tissue when compared with normal spleen. It is suggested that the reduction in the amount of white pulp present could explain at least in part the reduced ability of splenotic tissue to deal with infection.

A cadaveric study of injectate spread in the psoas compartment with a direct iliopsoas injection suggested for use during surgery.

Total hip replacement produces significant postoperative pain. Psoas compartment block is the most effective block of the lumbar plexus in terms of pain relief and reduced blood loss. It is a proven regional technique for analgesia and anaesthesia during and after total hip replacement conferring a number of benefits to the patient. However, traditional techniques used to produce this block require increased theatre time and are associated with a number of serious complications. We present a surgeon‐delivered technique for producing a lumbar plexus block using direct injection into the iliopsoas muscle when it is visible intraoperatively. This study shows a cadaveric model using methylene blue and radiopaque contrast produces injectate spread in a fashion which would produce a successful lumbar plexus block. This novel technique for lumbar plexus block affords the benefits of psoas compartment block with reduced complications and reduced administration time. Clin. Anat. 24:763–767, 2011.

Development of a model for occipital fixation—validation of an analogue bone material

Abstract Several implant systems may be used to fuse the skull to the upper cervical spine (occipito-cervical fusion). Current biomechanical evaluation is restricted by the limitations of human cadaveric specimens. This paper describes the design and validation of a synthetic testing model of the occipital bone. Data from thickness measurement and pull-out strength testing of a series of human cadaveric skulls was used in the design of a high-density rigid polyurethane foam model. The synthetic occipital model demonstrated repeatable and consistent morphological and biomechanical properties. The model provides a standardized enviroment for evaluation of occipital implants.

Computer-assisted learning in undergraduate psychiatry (CAL-PSYCH): evaluation of a pilot programme

OBJECTIVES To introduce and evaluate a computer assisted learning programme in undergraduate psychiatry (CAL-PSYCH). METHODS An interactive e-learning environment was created within the University College Dublin portal to assist students in acquiring the necessary skills in undergraduate psychiatry. The pilot phase consisted of providing their lectures on-line on the interactive site. Data were gathered from the last group of students in 2001 (pre-CAL-PSYCH) and the first group of students using CAL-PSYCH in 2002. We included assessment of percentage of students accessing the site, attendance rates at face-to-face lectures and tutorials, and also a feedback questionnaire from students who accessed the site. RESULTS All responders had used CAL-PSYCH. Students gave higher ratings for quality and interactivity of lectures compared with the pre-CAL-PSYCH curriculum. Students also expressed enthusiasm about CAL-PSYCH and encouraged us to develop it further. CONCLUSIONS Computer-assisted learning environments such as CAL-PSYCH provide the opportunity to bring modern e-learning techniques to medical education, and may provide a new model for life-long learning in medicine.