Stefan Kriegler

Improving inter-observer variability in the evaluation of ultrasonographic features of polycystic ovaries

BackgroundWe recently reported poor inter-observer agreement in identifying and quantifying individual ultrasonographic features of polycystic ovaries. Our objective was to determine the effect of a training workshop on reducing inter-observer variation in the ultrasonographic evaluation of polycystic ovaries.MethodsTransvaginal ultrasound recordings from thirty women with polycystic ovary syndrome (PCOS) were evaluated by three radiologists and three reproductive endocrinologists both before and after an ultrasound workshop. The following endpoints were assessed: 1) follicle number per ovary (FNPO), 2) follicle number per single cross-section (FNPS), 3) largest follicle diameter, 4) ovarian volume, 5) follicle distribution pattern and 6) presence of a corpus luteum (CL). Lins concordance correlation coefficients (rho) and kappa statistics for multiple raters (kappa) were used to assess level of inter-observer agreement (>0.80 good, 0.60 – 0.80 moderate/fair, <0.60 poor).ResultsFollowing the workshop, inter-observer agreement improved for the evaluation of FNPS (rho = 0.70, delta rho = +0.11), largest follicle diameter (rho = 0.77, delta rho = +0.10), ovarian volume (rho = 0.84, delta rho = +0.12), follicle distribution pattern (kappa = 0.80, delta kappa = +0.21) and presence of a CL (kappa = 0.87, delta kappa = +0.05). No improvement was evident for FNPO (rho = 0.54, delta rho = -0.01). Both radiologists and reproductive endocrinologists demonstrated improvement in scores (p < 0.001).ConclusionReliability in evaluating ultrasonographic features of polycystic ovaries can be significantly improved following participation in a training workshop. If ultrasonographic evidence of polycystic ovaries is to be used as an objective measure in the diagnosis of PCOS, then standardized training modules should be implemented to unify the approach to evaluating polycystic ovarian morphology.

Emphysematous pancreatitis: a less aggressive form of infected pancreatic necrosis?

Objective: Emphysematous pancreatitis is characterized by the presence of intraparenchymal pancreatic air in the setting of necrotizing pancreatitis. Mortality and morbidity rates approach approximately 40% and 100%, respectively. Traditionally, emphysematous pancreatitis was an indication for surgical intervention. The purpose of this review was to discuss our experience with nonoperative management of emphysematous pancreatitis. Methods: Between July 2005 and August 2007, 5 patients with emphysematous pancreatitis were admitted to Royal University Hospital (Saskatoon, Saskatchewan, Canada). The cases are described in the context of the current literature. Results: The 5 male patients ranged in age from 50 to 77 years. Four required at least 1 week in the intensive care unit. All 5 cases of emphysematous pancreatitis went on to be treated successfully with nonoperative management. Furthermore, after a minimum of 1-year follow-up, they remain out of hospital and continue to do well. Conclusions: Our data suggest that emphysematous pancreatitis may be a favorable subtype of severe pancreatitis. In well-selected patients, nonoperative management with aggressive antibiotic treatment and nutritional support may suffice.

Intrapancreatic accessory spleen: A case report and review of the literature

We present the case of a 26 year old male who was found to have a mass in the tail of the pancreas on an ultrasound scan. The lesion was suspicious for a non-functioning pancreatic neuroendocrine tumour (PNET) and so he underwent distal pancreatectomy. Pathology revealed this to be an intrapancreatic accessory spleen (IPAS). This is a rare entity, and the literature on this subject is reviewed. A lesion in the pancreas that enhances in a manner similar to the spleen, whether the contrast is used in the setting of a Contrast Enhanced Ultrasound, a contrast enhanced CT scan, or a gadolinium enhanced MRI scan, is suggestive of IPAS. Nonetheless, the majority of these rare lesions are likely to be surgically excised rather than observed due to the similar appearance to PNET.

Reactive hyperemia increases forearm vein area.

PurposeTo determine the effect of reactive hyperemia on human forearm vein area.MethodsAfter obtaining ethics approval and informed consent, an automatic tourniquet was applied to the forearms of 20 healthy subjects for one, two, and three minutes, at pressures of 25 mmHg, 200 mmHg, then 25 mmHg. A blinded radiographer measured the cross-sectional area of the cephalic vein at the wrist using ultrasonography. Measurements were recorded prior to tourniquet application and every minute thereafter for ten minutes, at each pressure setting and each time interval.ResultsThe mean vein cross-sectional area (mm2) increased from 8.22 ± 3.09 to 10.77 ± 3.50 after one minute of ischemia, from 8.31 ± 2.78 to 10.61 ± 2.77 after two minutes of ischemia, and from 8.39 ± 3.34 to 10.94 ± 3.46 after three minutes of ischemia (P < 0.05 for all). A tourniquet inflated to 25 mmHg for 13 min produced a mean vein cross-sectional area of 10.71 ± 3.25 mm2.ConclusionsReactive hyperemia causes human forearm vein cross-sectional area to increase. A low pressure tourniquet will also increase forearm vein area, but veins dilate more quickly during reactive hyperemia. This may have important clinical implications for attempting venous cannulation in patients with difficult venous access.RésuméObjectifDéterminer l’effet de l’hyperémie réactionnelle sur l’aire veineuse de l’avant-bras humain.MéthodeAyant obtenu l’accord du comité d’éthique et le consentement éclairé des participants, nous avons appliqué un garrot automatique à l’avant-bras de 20 sujets sains pendant une, deux et trois minutes, à des pressions de 25 mmHg, 200 mmHg, puis 25 mmHg. Un radiologue impartial a mesuré, par échographie, l’aire transversale de la veine céphalique au poignet. Les mesures ont été enregistrées avant la pose du garrot et à chaque minute par la suite pendant dix minutes, pour chaque pression établie et chaque intervalle de temps.RésultatsL’aire veineuse transversale moyenne (mm2) a augmenté de 8,22 ± 3,09 à 10,77 ± 3,50 après une minute d’ischémie, de 8,31 ± 2,78 à 10,61 ± 2,77 après deux minutes d’ischémie et de 8,39 ± 3,34 à 10,94 ± 3,46 après trois minutes d’ischémie (P < 0,05 pour toutes les mesures). Un garrot gonflé à 25 mmHg pendant 13 min a produit une aire veineuse transversale moyenne de 10,71 ± 3,25 mm2.ConclusionL’hyperémie réactionnelle augmente l’aire veineuse transversale de l’avant-bras chez l’homme. Un garrot basse pression l’augmente aussi, mais les veines se dilatent plus rapidement pendant l’hyperémie réactionnelle. Cela pourrait avoir d’importantes implications cliniques pour les essais de canulation veineuse en cas d’accès veineux difficile.

Epidural loss-of-resistance biomechanics: an open pilot cadaver study

Purpose We measured dynamic biomechanics of loss-of-resistance (LOR) epidural placement in prone cadavers, focussing on the period immediately following LOR, to estimate forces acting on the tissue of the epidural space. Methods An epidural syringe with 17G Hustead needle was instrumented to track force on the plunger, pressure in the chamber, and movement of barrel and plunger. Insertions were attempted in five formalin-preserved cadavers from T2–3 to L4–5, using LOR with saline or air, and confirmed with X-ray. Results Sixteen insertions were successful. Soft tissues in formalin-preserved cadavers are much harder than in living humans. With continuous pressure on the plunger, fluid thrust through the needle at the point of LOR was significantly greater (P = 0.005) with saline (mean ± standard deviation [95% confidence intervals]: 19.3 ± 14.9 [8.3 to 30.3] N); than with air (0.17 ± 0.25 [0 to 0.39] N). Stress exerted on epidural tissue was similar (air = 7792 ± 920 [6986 to 8598] Pa; saline = 7378 ± 3019 [5141 to 9614] Pa); and in both cases was greater than the stress exerted by cerebrospinal fluid pushing outwardly on the dura (4800 Pa). Conclusion Formalin-preserved cadavers are too stiff to make them an experimental model from which we can generalize to live humans, although we were successful in entering the epidural space and testing the instrumentation for further studies on live animals or humans. Continuous pressure on the plunger while advancing the epidural needle may “blow” the dura away from the needle tip and help prevent dural puncture. Better results are seen with saline rather than air.

Answer to Case of the Month #161: Internal Hernia Through the Foramen of Winslow

A 77-year-old woman presented with a 1-week history of intermittent right upper quadrant pain. She had no nausea, vomiting, jaundice, or temporal relationship of the pain to eating. Her surgical history included a hysterectomy and appendectomy. On physical examination, her right upper quadrant was tender to palpation and percussion, but there was no guarding, rebound tenderness, or flank pain. Laboratory tests were normal. A supine abdominal radiograph (Figure 1) and computed tomographic imaging (Figures 2, 3) was obtained.