A cadaver study evaluating intraluminal anomalies of the left common iliac vein.

OBJECTIVE: Intraluminal anomalies within the left common iliac vein, characteristic of iliac vein compression syndrome, are thought to result from compression by and pulsation of the overlying right common iliac artery. This cadaver study was designed to expand on the existing literature by surveying and photographing these spurs in addition to exploring whether certain factors, inherent to the cadaver, are associated with spur presence. METHODS: Dissection to expose the aorta, inferior vena cava, and common iliac arteries and veins was performed in 51 cadavers. The spinal level at which the iliac vein confluence occurred was noted. The point at which the right common iliac artery crossed the left common iliac vein was examined for plaque presence. The overlying arterial structures were then transected to expose the venous system. The inferior vena cava was incised to facilitate observation into the mouth and full extent of the left common iliac vein. Spurs were photographed and documented. Statistical analysis was conducted to determine whether sex, body mass index (BMI), plaque presence, or level of the iliac vein confluence are associated with spur presence. RESULTS: Spurs within the left common iliac vein were observed in 16 of 51 cadavers (31.4%). All spurs were located at the point that the right common iliac artery crossed the left common iliac vein. Using1 the classification system established by McMurrich, 67% of spurs (n = 10) were marginal and triangular; 25% (n = 4) were columnar. One marginal, linear spur (6%) and one partially obstructed spur with multiple synechiae (6%) were observed. Among this population, males were 73% less likely to have a spur (odds ratio, 0.269; P = .041). No significant relationship was found between plaque presence and spur presence (odds ratio, 0.933; P = .824) and no significant differences were noted between BMI and spur presence (χ2 = 1.752, P = .625). Last, a significantly greater percent of spurs was found within cadavers with an iliac vein confluence located at the L5/S1 disc space (χ2 = 9.650; P = .002). CONCLUSIONS: Study findings show that spurs are more common when the confluence of the common iliac veins occurs at a lower spinal level. The level of the iliac vein confluence may be important in identifying patients at increased risk of venous disease. The findings also suggest that plaque within the right common iliac artery and BMI display no distinct relationship with spur presence. Further investigation is needed to understand exactly what factors lead to spur formation.

Spatial Visualization of Human Anatomy through Art Using Technical Drawing Exercises.

Spatial visualization, the ability to mentally rotate three-dimensional (3D) images, plays a significant role in anatomy education. This study examines the impact of technical drawing exercises on the improvement of spatial visualization and anatomy education in a Neuroscience course. First-year medical students (n = 84) were randomly allocated into a control group (n = 41) or art-training group (n = 43). Variables including self-reported artistic drawing ability, previous technical drawing experience, or previous anatomy laboratory exposure were gathered. Participants who self-identified as artistic individuals were equally distributed between the two groups. Students in the art-training group attended four 1-hour sessions to solve technical drawing worksheets. All participants completed two Mental Rotations Tests (MRT), which were used to assess spatial visualization. Data were also collected from two neuroscience written examinations and an anatomical "tag test" practical examination. Participants in the art-training and control groups improved on the MRT. The mean of written examination two was significantly higher (P = 0.007) in the art-training group (12.95) than the control group (11.48), and higher (P = 0.027) in those without technical drawing experience (12.44) than those with (11.00). The mean of the anatomical practical was significantly higher (P = 0.010) in those without artistic ability (46.24) than those with (42.00). These results suggest that completing technical drawing worksheets may aid in solving anatomy-based written examination questions on complex brain regions, but further research is needed to determine its implication on anatomy practical scores. These results propose a simple method of improving spatial visualization in anatomy education.

Mapping a Danger Zone of the Dorsal Nerve of the Clitoris: Implications in Female Cosmetic Genital Surgery.

BACKGROUND: The literature regarding the route of the dorsal nerve of the clitoris is sparse and lacks surgical focus. With an increasing number of procedures being performed on the labia, it is important to elucidate the route and note any variation from normal of the nerve. METHODS: Fifty-one cadavers were dissected to yield 97 dorsal nerve of the clitoris samples. Measurements were taken from (1) the dorsal nerve of the clitoris penetration point of the perineal membrane to the urethra, (2) the nerve's penetration point of the perineal membrane to the pubic bone, (3) the angle of the clitoris to the branch point of the dorsal nerve of the clitoris, and (4) the branch point of the nerve to the distalmost point of the glans clitoris. Any anomalous branching patterns of the dorsal nerve of the clitoris were recorded and classified. RESULTS: The means and standard deviations of each measurement were used to create a surgical danger zone. The mean of each measurement was (1) 34.63 mm, (2) 5.74 mm, (3) -3.07 mm, and (4) 30.40 mm, respectively. In addition, six distinct branching patterns were observed, organized, and classified based on the location and number of branches observed. CONCLUSIONS: The dorsal nerve of the clitoris has multiple branching patterns and typically travels along the same course in most women. Further investigation of the course and three-dimensional position of the dorsal nerve of the clitoris is warranted to preserve sexual sensation as the frequency of procedures involving the female pudendum increases.

Depth Transitions of the Frontal Branch of the Facial Nerve: Implications in SMAS rhytidectomy.

BACKGROUND: Anatomy of the frontal branch of the facial nerve relative to the zygomatic arch and the superficial musculoaponeurotic system (SMAS) has been well described. The variability centers on the location where the frontal branch traverses from a deeper to more superficial plane in the SMAS. The goal of this study is to examine the depth transition of the frontal branch of the facial nerve relative to the zygomatic arch with hopes of pinpointing a caution zone for dissection to avoid nerve injury. METHODS: The frontal branch of the facial nerve was dissected in 36 hemifacial fresh cadaver specimens. Pitanguy's line, the zygomatic arch, and temporal crest were marked. Measurements were taken from the zygomatic arch to the location where the frontal branch pierced the temporoparietal fascia. Locations of the superficial temporal artery (STA), the frontal branch cross relative to the lateral orbital rim and frontalis muscle were also measured. RESULTS: In 94.4% (n = 36) of the specimens, the frontal branch was found to transition to an intra-SMAS plane approximately 9.6 mm above the zygomatic arch. In all specimens, the frontal branch transitioned to an intra-SMAS plane approximately 12.2 mm posterior to Pitanguy's line. CONCLUSIONS: This study describes a surgical "caution zone" centered on a point 9.6 mm above the arch and 12.2 mm posterior to Pitanguy's line, and related to the anterior branch of the STA. We hope this anatomical detail will help to decrease the likelihood of intraoperative injury to the frontal branch of the facial nerve.

Student perceptions of online and in-person microbiology laboratory experiences in undergraduate medical education.

Background: Universities are facing increased budget constraints, often resulting in reduced funds to support microbiology laboratories. Online mock laboratory activities are often instituted as a cost-effective alternative to traditional wet labs for medical students.Objective: The purpose of this study was to examine students' perceptions of online and in-person microbiology lab learning experiences.Design: We investigated undergraduate medical student perception of the in-person and online microbiology lab experience; 164 first-year medical students participated in newly designed online labs, while 83 second-year medical students continued to use in-person labs. An online survey was administered to collect student opinions of the lab experience.Results: In terms of student self-reported learning styles, those students who attended the lab in person were more likely to report a tactile learning style (33% vs 16%) while those students who learned the material online reported a visual learning style preference (77% vs 61%; n = 264). Students felt that the online microbiology lab was more convenient for their schedules when compared to the in-person lab. A greater proportion of online students (12%) felt that they encountered brand-new material on the final quiz than in-person students (1%; n = 245). Even so, 43% of the online educated students and 37% of the in-person educated students perceived their assigned lab experiences to be the optimal lab design, and over 89% of both groups reported a desire for at least some in-person instruction in a wet-laboratory environment.Conclusions: Our findings suggest that, while students are strongly supportive of digital online lab activities, the overwhelming majority of students still report a desire for a blend of online and in-person, hands-on laboratory activities. These findings will further research directed towards student perception of the lab experience and aid in the adaptation of microbiology curriculums to accommodate both student and university needs.

Effect of phenylephrine 1.0%-ketorolac 0.3% injection on tamsulosin-associated intraoperative floppy-iris syndrome.

PURPOSE: To determine the effect of phenylephrine 1.0%-ketorolac 0.3% injection (Omidria) on different components of intraoperative floppy-iris syndrome (IFIS). SETTING: Silverstein Eye Centers, Kansas City, Missouri, USA. DESIGN: Prospective case series. METHODS: Men treated with tamsulosin having standard cataract extraction surgery were placed in a treatment group that received phenylephrine 1.0%-ketorolac 0.3% injection in the irrigation solution and a control group) that received basic saline solution. Every procedure was video recorded using an endocyclophotocoagulation (ECP) probe and microscopic view. Pupil dilation, iris billowing, and iris prolapse were measured using a micrometer, ECP recording grading scale, and microscopic recordings, respectively. RESULTS: Each group (treatment and control) comprised 25 eyes of 25 patients. Although both groups had a decrease in pupil diameter before and after cataract extraction and before cataract extraction and after intraocular lens implantation, the changes were statistically significantly greater in the treatment group. Iris prolapse occurred in 3 patients (12.0%) in the treatment group and 14 patients (56.0%) in the control group (P < .001). Stage 3 (severe) pupil billowing occurred in 1 eye (4.0%) in the treatment group and 10 eyes (40.0%) in the control group (P < .001). CONCLUSIONS: The use of the phenylephrine 1.0%-ketorolac 0.3% injection combination added to the irrigating solution during cataract surgery in patients at risk for IFIS led to significantly better prevention of miosis, less pupil billowing, and a reduced incidence of iris prolapse. A new grading scale for intraoperative iris abnormalities might be used for future evaluation.

Using anatomical landmark to avoid phrenic nerve injury during balloon-based procedures in atrial fibrillation patients.

PURPOSE: Atrial fibrillation (AF) is an arrhythmia which affects as many as 2.7 million Americans. AF should be treated, because it can lead to a four-to-fivefold increased risk of experiencing a stroke. The American College of Cardiology/American Heart Association guidelines for the treatment of drug refractory and symptomatic paroxysmal AF denote catheter ablation as the standard of care. The newest ablation treatment, cryoballoon, uses a cold balloon tip. The biggest risk factor associated with the cryoballoon ablation is phrenic nerve injury (PNI). The purpose of this study is to measure relevant distances from specific landmarks to the right phrenic nerve (RPN) to create a safe zone for physicians. METHODS: Using 30 cadaveric specimens, we measured laterally from the right superior pulmonary vein orifice (RSPV) to the RPN at the level of the sixth thoracic vertebra and laterally from the lateral border of the sixth thoracic vertebral body (T6) to the RPN. The depth and width of the left atrium (LA) were also measured to establish a cross-sectional area of the LA. The cross-sectional area of the LA was then correlated with the averaged measurements to see if the area of the LA could be a predictor of the location of the RPN. RESULTS: The average distance from the RPN-RSPV was 9.6 mm (range 4.3-18.8 mm). The average RPN-T6 distance was 30.6 mm (range 13.7-49.9 mm). There was a non-significant trend that suggests as the size of the LA increases, the measured distances also increased. CONCLUSION: Using the lateral border of the sixth thoracic vertebra as a landmark, which can be viewed under fluoroscopy during the procedure, physicians can triangulate the distance to the RSPV and determine the approximate position of the RPN. Furthermore, physicians can perform a preoperative echocardiogram to determine the size of the LA to assist in determining the position of the RPN with the hopes of avoiding injury to the RPN.

Prevalence of Nasal Colonization by Methicillin-Resistant Staphylococcus aureus in Persons Using a Homeless Shelter in Kansas City.

Nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in the epidemiology and pathogenesis of disease. Situations of close-quarter contact in groups are generally regarded as a risk factor for community-acquired MRSA strains due to transmission via fomites and person-to-person contact. With these criteria for risk, homeless individuals using shelter facilities, including showers and toilets, should be considered high risk for colonization and infection. The aim of this study was to determine the prevalence of nasal colonization of MRSA in a homeless population compared to established rates of colonization within the public and a control group of subjects from a neighboring medical school campus, and to analyze phylogenetic diversity among the MRSA strains. Nasal samples were taken from the study population of 332 adult participants and analyzed. In addition, participants were surveyed about various lifestyle factors in order to elucidate potential patterns of behavior associated with MRSA colonization. Homeless and control groups both had higher prevalence of MRSA (9.8 and 10.6%, respectively), when compared to the general population reported by previous studies (1.8%). However, the control group had a similar MRSA rate compared to health-care workers (4.6%), while the homeless population had an increased prevalence. Risk factors identified in this study included male gender, age over 50 years, and use of antibiotics within the past 3 months. Phylogenetic relationships between nine of the positive samples from the homeless population were analyzed, showing eight of the nine samples had a high degree of relatedness between the spaA genes of the MRSA strains. This indicates that the same MRSA strain might be transmitted from person-to-person among homeless population. These findings increase our understanding of key differences in MRSA characteristics within homeless populations, as well as risks for MRSA associated with being homeless, such as age and gender, which may then be a useful tool in guiding more effective prevention, treatment, and health care for homeless individuals.

Examining body mass index in an urban core population: from health screening to physician visit.

UNLABELLED: BACKGROUND. Childhood obesity is commonly encountered in the primary care office and disproportionately affects those from low income or minority backgrounds. OBJECTIVE: To determine how accurately primary care clinicians in an urban setting identified patients with body mass indices (BMIs) at or above the 95th percentile for age and to determine which obesity treatment strategies are used. MATERIALS AND METHODS: The study population consisted of school-aged, inner-city children with a BMI at or above the 95th percentile for age whose charts were made available for data collection by retrospective chart review. RESULTS: A total of 158 patient medical charts were reviewed. Of these, 90 (57%) patients failed to be identified by the provider as having an elevated BMI. Obesity treatment was initiated in only 68 (43%) of these patients. CONCLUSIONS: Providers are not effectively recognizing childhood obesity and are not consistently implementing effective obesity treatment strategies.

Prescribing trends for management of congestive heart failure from 2002 to 2004.

BACKGROUND: The incidence and prevalence of the patients diagnosed with congestive heart failure (CHF) continues to grow in the United States. The use of prescription drugs is a vital part of the management of CHF, and pharmacological regimens may vary among patients. OBJECTIVES: To examine the CHF prescription trends in the United States and to determine present prescribing patterns. METHODS: National Ambulatory Medical Care Survey and both divisions (outpatient and emergency department) of the National Hospital Ambulatory Medical Care Survey from 2002 to 2004 were used to acquire the appropriate data. All analyses used weighted data to represent national estimates. The unit of analysis was individual patient visits. Analysis of the data was accomplished using SPSS 14.0.2 and Stata/SE 9.2 statistical programs. RESULTS: During the 3 study years, 24,213,096 weighted visits were associated with a diagnosis of CHF. More than half (56.2%) of the study population were female; over 75% of the subjects were older than 65 years. Over one-quarter (27.3%; 6,618,208 visits) of CHF-related visits were not associated with being prescribed a CHF-related medication. Loop diuretics were the most commonly used medication (35%). Cardiovascular specialists (odds ratio [OR]=5.28; 95% confidence interval [CI]: 1.82-15.3; P=.002), general/family practice physicians (OR=4.5, 95% CI: 1.69-12.0; P=.003), and internal medicine physicians (OR=3.85, 95% CI: 1.39-10.7; P=.010) were more likely to prescribe CHF-related medication compared with other medical specialties. CHF patients who reside in the Northeast were more likely to receive CHF-related medications than other regions (Midwest OR=0.24; South OR=0.20; West OR=0.23; P<.05) of United States. CONCLUSIONS: There were regional and medical specialty-related variations for prescribing CHF-related medications. The results from this study suggest a need for increased awareness of the benefit of CHF-related medications in the management of CHF. The increased implementation of the CHF management guidelines would improve overall patient care.

Case of ischemic colitis in a young adolescent associated with triphasic hormonal contraceptive therapy: a case report and review of the literature.

There has been speculation that third generation hormonal contraceptives may be less prone to inducing clotting than the earlier generation products. We present a case of colonic ischemia in a young adolescent receiving pharmacotherapy with a third-generation hormonal contraceptive. Ischemic colitis is an uncommon adverse effect in young adolescents associated with hormonal contraception, especially the third generation agents. We believe this case to be the second-youngest patient reported with ischemic colitis due to this therapy. Clinical vigilance is recommended for women presenting with abdominal pain, with or without hematochezia, who are receiving hormonal contraceptive therapy. Since their introduction in the early 1960's, the combination hormonal contraceptives have been utilized by millions of women for both contraceptive and non-contraceptive purposes. Although a variety of adverse effects can be experienced by individuals taking these agents, it has been demonstrated that these agents are associated with an increased risk of venous and arterial thromboses. Publications more consistently report on the cardiovascular-, pulmonary-, peripheral vascular-, or cerebrovascular-based thrombotic events associated with these agents. During the past several decades changes have been incorporated in the dose and types of compounds included in the combination hormonal contraceptive products in an attempt to reduce the risk of coagulation and other adverse effects. Less common and less frequently publicized are the gastrointestinal-based thrombotic events that result in ischemia and presents as severe abdominal pain, with or without hematochezia. We report an uncommon case of reversible colonic ischemia in who we believe to be the second-youngest adolescent female reported in the literature (youngest aged 16 years) to have this diagnosis associated with the use of a newer, third-generation oral combination hormonal contraceptive (Naranjo scale of 7; Probable).

Assessment of antihyperlipidemic therapy in US patients with coronary heart disease.

CONTEXT: Knowledge of the trends and possible differences in the use of antihyperlipidemic medications in US patients with coronary heart disease (CHD) is vital in order to stimulate a positive change in the health of society. OBJECTIVE: To assess, in the ambulatory setting, the frequency of antihyperlipidemic medication use in US patients with CHD. DESIGN: Retrospective, national, cross-sectional study using data from the 2004 National Ambulatory Medical Care Survey (NAMCS). METHODS: Ambulatory medical visits surveyed by the 2004 NAMCS associated with select ICD-9-CM CHD-related diagnoses were included. Use of antihyperlipidemic medications was captured by searching the database for drug names. Demographics assessed for association with antihyperlipidemic therapy included region of the country in which care was provided; patient age group, sex, ethnicity, and race; physician medical degree; and payment type. Statistical analyses used sample weights to determine national estimates. RESULTS: A weighted national estimate of nearly 16 million ambulatory medical care visits was made in the United States in 2004 of patients with one of the selected CHD diagnoses. Use of any form of lipid-lowering therapy was associated with 40.4% of the CHD patients seeking ambulatory-based medical care in 2004. Non-Hispanic/Latino patients with CHD were more than 4.5 times more likely to be receiving lipid-lowering therapy (odds ratio [OR], 4.59; 95% CI, 1.28-16.37). Patients with CHD who had Medicare as their form of payment for healthcare were less likely to be receiving lipid-lowering therapy (OR, 0.50; 95% CI, 0.28-0.91), as were those receiving medical care in the South region of the United States (OR, 0.36; 95% CI, 0.14-0.89). Similar differences in medication use were noted with the statin medication class. CONCLUSION: In 2004, less than half of the ambulatory medical visits by US patients with CHD were associated with antihyperlipidemic treatment, and most of these patients were treated with one medication (a statin). A CHD patient's reported ethnicity, primary method of payment, and area of the United States in which care was received all demonstrated differences. On the basis of the growing evidence-based medical literature, it is imperative to continue this research to assess changes in future trends and to work with healthcare and policy advocates to strike a positive change for all patients.

Assessing prescriptions for statins in ambulatory diabetic patients in the United States: a national, cross-sectional study.

BACKGROUND: Diabetes mellitus affects >20 million people in the United States each year, and >4000 new cases are diagnosed daily. OBJECTIVE: This study assessed the prescription of statin medications in the ambulatory setting in US diabetic patients. METHODS: We used data from the 2002 through 2004 National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey. All ambulatory medical visits associated with a diabetes diagnosis by the International Classification of Diseases, Ninth Revision, Clinical Modification were included. Prescriptions for statin medications were determined by searching each ambulatory visit for relevant drug names (trade and generic). Demographic characteristics were assessed, including survey year, sex, age group, race, ethnicity, payment type, region of the country, and physician's specialty and degree. Analyses used sample weights to calculate national estimates. RESULTS: From 2002 to 2004, 10,046 (unweighted) ambulatory visits were made by diabetic patients, representing a weighted national estimate of approximately 153 million visits. A statin prescription was associated with 21.1% of all diabetic visits and 14.1% of those without a hyperlipidemia-related diagnosis. Diabetic men were more likely than diabetic women to be given a prescription for a statin (odds ratio [OR], 1.38; 95% CI, 1.09-1.73). Compared with diabetic patients treated in 2002, those treated in 2003 and 2004 were more likely to be prescribed statin therapy (2003 OR, 1.51; 95% CI, 1.02-2.24; 2004 OR, 1.48; 95% CI, 1.03-2.15). Compared with diabetic patients aged 45 to 64 years, those in younger age groups were less likely to be given a statin prescription (1-24 years OR, 0.10; 95% CI, 0.01-0.84; 25-44 years OR, 0.48; 95% CI, 0.31-0.74), and those aged 65 to 74 years were more likely to be given a statin (OR, 1.38; 95% CI, 1.01-1.90). No differences were noted for diabetic patients aged > or = 75 years. CONCLUSIONS: From 2002 through 2004, <25% of the ambulatory medical visits by diabetic patients in the United States were associated with a statin prescription. Male sex and age up to 75 years had an increased association with statin prescription. Additional study is anticipated to assess changes in statin use in diabetic patients in the United States as updated treatment guidelines are released.