Evaluating patients with renal failure for renal artery stenosis with gadolinium-enhanced magnetic resonance angiography.

The incidence and prevalence of end-stage renal disease (ESRD) continues to increase, especially in the elderly population. The role of renovascular disease in contributing to ESRD is still not well defined. The objective of this study was to determine the utility of gadolinium (Gd)-enhanced magnetic resonance angiography (MRA) in evaluating elderly patients with renal insufficiency for renal artery stenosis (RAS). A 7-month prospective study conducted in a tertiary referral center evaluated 40 consecutive patients with progressive renal insufficiency (18 men and 22 women; mean age, 70 +/- 5.6 [standard deviation] years) and high clinical suspicion for renovascular disease with Gd-enhanced MRA. Digital subtraction angiography (DSA) was obtained in only those patients with significant RAS detected by MRA. Twelve patients had significant RAS. Six of these patients had percutaneous transluminal renal angioplasty (PTRA), five patients had renal artery bypass surgery, and one patient had a stent placed after PTRA. Seventy-eight renal arteries were satisfactorily evaluated by MRA. Twenty-two renal arteries were evaluated by both MRA and DSA. Of the 12 significant stenoses detected by the MRA, 11 were confirmed by DSA and 1 was confirmed at the time of surgical revascularization. It is concluded that Gd-enhanced MRA is a useful test for the evaluation of RAS in patients with compromised renal function.

The pyridine scale for clinical measurement of olfactory threshold: a quantitative reevaluation.

Serial dilutions of pyridine in water are employed for measuring the olfactory detection thresholds of patients. Experimental precautions are described that improve the precision and accuracy of the method. Existing data on the sensitivities of hyposmic patients are confirmed, but the sensitivities of normal subjects and of hyperosmic patients are believed to have been substantially overestimated in some earlier publications. Routine clinical applications of the revised pyridine odor threshold test are discussed. In the author's experience, the average cystic fibrosis patient is slightly hyposmic, and some cases of pituitary tumor are accompanied by a 100,000-fold hyperosmia.

Acetylcholinesterase levels in nasal turbinate congestion.

In a previous communication, one of the authors discussed prolonged congestion of the turbinates following nasal surgery. The clinical factors responsible were allergy or the traumatic effects of nasal packing on the turbinates. A study of turbinate function was done to find the factor responsible for this congestion. Biopsies of an inferior turbinate were obtained preoperatively and two weeks after surgery. The specimens were examined for the level of acetylcholinesterase by histochemical assay and were also studied by examining sections histologically. In the majority of cases, the level of acetylcholinesterase fell with the appearance of congestion and rose when the turbinates returned to normal. These results suggest a connection between turbinate congestion and levels of tissue acetylcholinesterase in the presence of inflammation or allergy.

A study of nasal airway function in the postoperative period of nasal surgery.

One hundred fifty-seven consecutive nasal surgery cases were followed for a minimum of one year or more. Ten cases were considered to have unsatisfactory mechanical airways, caused either by return of the original pathology (alar collapse or atrophic rhinitis) or by inadequate mechanical results. Nineteen cases in which the mechanical airways were satisfactory had soft tissue obstruction secondary to chronic inferior turbinate congestion. The effects of nasal allergy and the trauma of postnasal packing on chronic congestion of the turbinates are tabulated according to the type of surgery performed and results discussed.