PC1 U2L7

when is screening important?

birth, childhood, pregnancy, aging

when do we screen for pregnancy

prior to starting meds that may cause complications or birth defects, radiation, or surgical procedures that could result in fetal loss

urine hcg

can be performed at POC, positive results obtained if quantity in urine is at least 5 IU/L

serum HCG

blood sample collected in serum separator tube (SST), has to be sent to lab, resulted as quantitative level

purpose of colonoscopy

allows for visualization of entire colon from anus to cecum and portion of terminal ileum

what does colonoscopy allow for dx wise

cancer, benign polyps, ulcers, AV malformations

what can be used to coagulate sites of active bleeding during a colonoscopy

laser, electrocoagulation, sclerosing agents

colonoscopy indications

changes in bowel habits, obvious or occult blood in stool, surveillance of patients with colorectal CA, IBD, polyposis

possible complications of colonoscopy

bowel perforation, biopsy site continued bleeding, respiratory depression from oversedation

interfering factors of colonoscopy

poor bowel prep, active bleeding

contraindication of colonoscopy

patient inability to consent, medically unstable, profuse rectal bleeding, suspected colon perforation, recent colon anastomosis

preparation for colonoscopy

polyethylene glycol solution (PEG) or OTC regimen using magnesium citrate and miralax

screening mammogram

2 views, no ultrasound

diagnostic mammogram

multiple views with possible ultrasound to follow

prostate specific antigen (PSA)

found in high concentration in the prostatic lumen, physical barriers prevent from traveling outside of the lumen to the blood stream

what could compromise the integrity of the PSA system

cancer, BPH, infection

what do higher PSA levels indicate

increased permeability and higher grade of tumor

screening with PSA

serum test, testing in asymptomatic men is controversial!!!

factors affecting PSA measurement

5-alpha reductase inhibitors (for BPH)

• finasteride

• dutasteride

NSAIDs

statins

thiazides

other causes of high PSA

BPH, prostatic inflammation and infection, perineal trauma and sexual activity, DRE vs prostatic massage, mechanical instrumentation (cysto, BX, TURP), acute urinary retention or recent urethral instrumentation

what is a pap smear

collection of cells from the transition zone of the cervix using a broom, spatula, cells looked at under microscope and abnormalities are further characterized using a larger tissue sample from colposcopy

colposcopy

biopsy of cervix, uses acetic acid solution as a wash for the cervix, performed based on areas of visualized abnormality, endocervical curettage, hemostasis with silver nitrate or monsel’s solution

what is acetowhite lesion

HPV affected tissue turns white with acetic acid solution of the cervix

what is an ultrasound

non-invasive imaging modality, uses high-frequency sound waves to create real-time images, no ionizing radiation

how ultrasound works

transducer sends sound waves, waves reflect off tissues and echos convert into visual images on the monitor

common ultrasound modes

b-mode (brightness mode)

m-mode (motion mode)

doppler mode

b-mode

standard grayscale imaging

m mode

useful for moving structures (heart valve)

doppler mode

assesses blood flow (color and spectral doppler)

advantages of ultrasound

bedside accessibility, no radiation, realtime imaging, cost effective and portable

limitations of ultrasound

operator dependent, limited by patient body habitus, cannot image through air (lungs, bowel) or bone, requires hands-on training to master

clinical applications of ultrasound

abdominal: gallbladder, aorta, kidneys

cardiac: echocardiography

obstetrics/gynecology: pregnancy eval

vascular: DVT detection, carotid studies

musculoskeletal: joint effusions, tendon tears

point of care ultrasound

performed at bedside by clinician, rapid answers for urgent questions, increasingly used in ER, ICU, primary care

pelvic ultrasound

preferred method of diagnostic evaluation in women’s health due to lack of radiation, less risk of inducing cancerous changes long term, able to visualize pelvic structures

abdominal ultrasound findings in kidney, bladder

cysts, tumors, calaculi, hydronephrosis, malformations, abscess, transplant rejection

abdominal ultrasound findings in abdominal aorta

aneurysm

abdominal ultrasound findings in liver

cysts, abscess, dilated hepatic ducts, tumors

abdominal ultrasound findings in gallbladder, extrahepatic ducts

gallstones, polyps, dilation secondary to structures or tumors

abdominal ultrasound findings in pancreas

tumors, pseudocysts, inflammation, abscess

interfering factors in abdominal ultrasound

barium and gas distort sound waves, skillset of sonographer, obesity (altered by fatty tissue)

what are nuclear scans

imaging studies that use radiotracers (injected, inhaled, or ingested) and detected by gamma camera or PET scanners to create images

how nuclear scans work

1. radiotracers accumulate in specific organs or tissues (accumulation is hot spot, lack of absorption of tracer is cold spot)

2. emit gamma rays or positrons

3. scanner detects emissions and constructs functional images

4. focus on function rather than just structure

types of nuclear scans

positron emission tomography (PET)

single photon emission computed tomography (SPECT)

bone scans

thyroid scans

cardiac perfusion scans (MUGA)

advantages of nuclear imaging

sensitive to early disease processes (before structural changes), provides metabolic and functional information, can identify cancer, infection, ischemia and more, helpful in staging disease

limitations and considerations of nuclear imaging

exposure to low dose radiation, time consuming, not suitable for pregnant patients, may require complimentary imaging (MRI, CT)

clinical applications of nuclear medicine scans

oncology: PET for cancer detection, staging, recurrence

cardiology: stress/rest cardiac perfusion scans

endocrinology: thyroid uptake and scan

orthopedics: bone scan for fractures, infection, metastases

infectious disease: detect abscesses or osteomyelitis

DEXA scan (dual energy x ray absorptiometry)

uses low dose radiation to determine the density of the bones of a patient’s hip and spine, can be used for screening and dx, T-score or Z-score

what is a normal t score

between +1 and -1

osteopenia t score

between -1 and -2.5

osteoporosis t score

-2.5 or less