What's Up Doc 11-12-09

What is the difference between myopia and hyperopia?
Myopia is commonly called nearsightedness, and occurs when the curvature of the cornea is too steep, causing focus of the rays of light to form in front of the retina instead of directly on the retina. The result is a blurry view of distant objects. Hyperopia is commonly referred to as farsightedness, and occurs when an eye is too short for the cornea curvature, causing focus of the rays of light to form behind the retina instead of directly on the retina. As a result, a blurred image of close objects is produced.
Jeffrey Hankin, OD, Optometrist with The Eye Clinic

I got an email that said it was not safe to microwave my food in plastic wrap. Is this true or is this an urban myth?
This Internet string was created by an unknown author who got a little carried away about dioxins in the atmosphere. While it is true that the microwaving process releases dioxins, there is only an insignificant amount of these poisons released. Once dioxins enter the body, they are stored in the fatty tissues of the body. Excessive amounts of dioxins can cause problems if you are exposed to them for an extended period of time and in large amounts. Dioxins in plastic wrap are essentially harmless. You can feel confident using any plastic that is marked microwaveable in the microwave. The vast majority of plastics used in food wraps and packaging containers do not contain the chemical constitutes that can form dioxins, which are a family of compounds produced by combustion at temperatures greater than 700 degrees Fahrenheit. And, by the way, if you just so happened to be cooking at that temperature, you wouldn’t be able to eat that crunchy stuff anyway!
Brian Stewart, MD, family practice physician

How Does Chemotherapy Affect Diabetes?
Chemotherapy is a challenging treatment for anyone, but presents some additional specific concerns for people who have diabetes. Some people react to the stress of chemotherapy on the body by developing additional resistance to insulin, so that blood sugar levels increase. This is a temporary effect, but it may cause a diabetic to require additional medication during treatment. Side effects of chemotherapy can include irritation of the digestive tract, including mouth sores, nausea, and diarrhea. If this occurs, you may not eat as well and absorb your nutrients poorly. While nutrition is poor, you may require supplemental nutrition through an intravenous (IV) line. Changes in your total calorie intake will make it necessary for your diabetes treatment to be monitored and adjusted throughout your treatment. It is also common for people who receive intravenous nutrition to receive intravenous insulin out of the same infusion, if the doctor makes this arrangement. Some side effects of chemotherapy are long lasting. One common side effect of certain chemotherapy medicines is nerve damage, called "neuropathy." Because neuropathy is also a common complication of diabetes, these patients may be particularly prone to this problem after chemotherapy.
Henry Goolsby, III, MD, Oncologist with Lake Charles Medical and Surgical Clinic

I have a bump under the skin of my left wrist that comes and goes every few months. Sometimes it is sore and other times I don’t even realize it is there until I accidentally hit it on something. It usually stays for about three or four weeks and then disappears. Should I be concerned?
It sounds like you have a very common ganglion cyst. They are not harmful and can be treated by removal if they severely impact the use of your wrist or hand. Unfortunately, even with surgery, the cysts tend to come back. If the bump becomes too painful, a wrist splint may provide relief. Of course, it’s always best to check with your physician so he or she can look at it and give you more specific instructions.
Marne Devillier, MD, family medicine physician with Maplewood Family Medical Clinic

What's Up Doc 10-29-09

I’m getting aggravated that I’m still dealing with acne at age 27. I thought I would be done with this by now. It’s not very professional looking, either. What kind of treatments are available?
If it’s any consolation, nearly 30 percent of women and 20 percent of men ages 20 to 60 battle breakouts. Over-cleaning and vigorous scrubbing can cause more damage, so keep in mind it’s best to be gentle, but consistent. Wash morning and night with a gentle cleanser, and it’s especially important to remove makeup every night. A topical treatment containing benzoyl peroxide will kill bacteria. For moderate to severe acne, a prescription treatment can often provide good results. Also, avoid touching your face throughout the day, wash your hands frequently, and limit sun exposure as this can increase oil production and make acne worse. A treatment plan by a dermatologist can help minimize the breakouts.
Maureen Olivier, MD, dermatologist with The Clinic

How effective are whitening toothpastes?
All toothpastes help remove surface stains through the action of mild abrasives. Some whitening toothpastes contain gentle polishing or chemical agents that provide additional stain removal effectiveness. Whitening toothpastes can help remove surface stains only and do not contain bleach. Over-the-counter and professional whitening products contain hydrogen peroxide (a bleaching substance) that helps remove stains on the tooth surface as well as stains deep in the tooth. None of the home use whitening toothpastes can come even close to producing the bleaching effect you get from your dentist's office through professional tooth whitening techniques. Whitening toothpastes can lighten your tooth's color by about one shade. In contrast, light-activated whitening conducted in your dentist's office can make your teeth three to eight shades lighter.
Harry Castle, DDS, with Oak Park Dental

I’d like to have Botox, but I’m worried about my facial expressions not looking natural. Is that unavoidable?
Not at all – if the injections are administered correctly. Botox works best for dynamic wrinkles. These are the wrinkles that occur when you smile, laugh or frown. They are commonly referred to as frown lines, forehead lines and crow's feet. Although the results after Botox are visible, a treatment with Botox injections will not radically change your facial appearance or make you look as if you "had work done." The muscle activity that causes frown lines between the brows is simply reduced, so you can still frown or look surprised.
Mark Crawford, MD, facial cosmetic specialist with the Aesthetic Center of SWLA

What might cause sensitivity and persistent pain in the hip?
Hip pain can be caused by various factors. One of the most common is degenerative joint disease or osteoarthritis. This occurs when the cartilage lining, which keeps the bones in the hip joint gliding across each other smoothly, deteriorates and becomes rough. The pain and stiffness that are associated with arthritis can also be accompanied by a tingling or warm sensation. Another possible condition related to these symptoms is bursitis of the hip joint. This occurs when the bursa sac surrounding the hip joint becomes inflamed. A stress fracture can cause persistent pain and discomfort in the hip. A new source of hip pain has been isolated in the labrum of the hip. The labrum is a ring of cartilage surrounding the hip joint, which can be torn and is a very common cause of hip pain in younger patients. Finally, very often what people think is hip pain is not actually related to a problem in the hip joint. It can originate from some other condition such as a herniated disc in the back. In order to determine the exact cause of your hip pain, don't delay seeing a qualified physician for an examination.
John Noble, Jr., MD, orthopaedic surgeon with Center for Orthopaedics