Standardized time to peak in ischemic and regular cerebral tissue measured with perfusion MR imaging.

BACKGROUND AND PURPOSE: Standardized time to peak (stdTTP) enables a quick quantification of time to peak measurements. An stdTTP /=7 seconds indicates critically perfused tissue. We verified this stdTTP in acute ischemia (within the first 6 hours after the onset of symptoms), when perfusion is critical, and after 24-72 hours. METHODS: Combined diffusion-weighted imaging (DWI) and perfusion MR imaging was performed in 20 consecutive patients with acute cerebral ischemia. Distributions of stdTTP >/=7 and /=7 seconds. StdTTP of about 80% of voxels was /=7 seconds and resulting infarct (r(2)=0.86). CONCLUSION: StdTTP is reciprocal in regions with and without ischemic injury. An stdTTP >/=7 seconds (regular range) is strongly correlated with resulting infarct and reflects critical perfusion with a high probability of ischemic tissue injury in acute ischemia, whereas this is unlikely in regions with stdTTP

Effects of 12 months of recombinant growth hormone therapy on parameters of bone metabolism and bone mineral density in patients on chronic hemodialysis.

BACKGROUND: Renal osteodystrophy is common in patients with chronic renal failure (CRF) on hemodialysis (HD), leading to reduced bone mineral density (BMD) and higher bone fracture incidences. Since growth hormone (GH) and insulin-like growth factor 1 (IGF-1) are known to enhance bone metabolism and BMD, and CRF patients exhibit GH and IGF-1 resistance, recombinant human GH (rhGH) therapy could be beneficial for these patients. METHODS: This study evaluated the effects of a 12-month rhGH therapy on bone metabolism parameters; alkaline phosphatase (AP), osteocalcin (OC), procollagen I carboxyterminal propeptide (PICP), telopeptide ICTP, serum crosslaps, n-terminal propeptide of type III procollagen (PIIINP) and intact parathyroid hormone (iPTH), as well as on BMD of the lumbar spine and the femoral neck in 19 malnourished HD patients (10 females, 9 males) with a mean age of 59.3 +/- 13.4 yrs. Fourteen patients completed the 12-month study. RhGH (0.25 IU/kg) was given subcutaneously 3x/week after each dialysis session. RESULTS: IGF-1 concentrations rose significantly from 169.2 +/- 95.6 to 262.9 +/- 144.4 ng/mL (p<0.01) after 3 months, followed by a slight decline over the next 9 months. PICP as a bone formation marker significantly increased after 3 months from 250.1 +/- 112.6 to 478.5 +/- 235.2 ug/L (p<0.01), as well as PIIINP, whereas OC and bone resorption parameters like ICTP showed only a slight increase (ICTP: 50.3 +/- 18.5 to 70.0 +/- 39.5 ug/L after 3 months (ns)). All bone metabolism parameters slightly declined in the following 9 months, but remained above baseline values after 12 months. PTH rose from 198.0 +/- 139.2 to 456.0 +/- 268.7 ng/ml, p<0.01 after 6 months. BMD of the lumbar spine showed a significant reduction after 3-month rhGH therapy (0.80 +/- 0.17 vs. 0.77 +/- 0.16 g/cm2, p<0.01), but returned to baseline values after 12 months. BMD of the femoral neck remained stable during the entire study. CONCLUSIONS: In summary, 12-month rhGH treatment in patients on chronic HD caused a significant increase in IGF-1, together with an increase in bone turnover. In addition, there was a temporary reduction in BMD of the lumbar spine seen, which returned to baseline values after 12 months.

Are repeat biopsies required in men with PSA levels < or =4 ng/ml? A Multiinstitutional Prospective European Study.

OBJECTIVES: Pathological and biochemical features of prostate cancers detected on repeat biopsies in men with total PSA level between 2.0 and 4 ng/ml were evaluated and compared to those cancers detected on first biopsy. METHODS: 315 men with PSA level between 2.0 and 4 ng/ml underwent transrectal ultrasound guided sextant biopsy and two additional transition zone biopsies (Octant Biopsy). All subjects whose biopsy samples were negative for prostate cancer underwent a repeat biopsy after 6 weeks. Those with clinically localized cancers were offered surgery or radiation therapy. Pathological and clinical features of patients diagnosed with prostate cancer on initial and repeat biopsy were compared. RESULTS: Cancer detection rates on first and second biopsy were 24% (75/315) and 13% (29/224), respectively. Overall, of patients with clinically localized disease (83% of cancers detected), 87% underwent radical prostatectomy, 11% opted for radiation therapy and 2% opted for watchful waiting. Cancers found in the first biopsy group were more multifocal (p = 0.01) while cancers found on second biopsy were more located in the apical-dorsal region (p = 0.003). No significant differences were noted with respect to extracapsular extension, seminal vesical invasion, positive margins, final pathological stage, Gleason score, percentage Gleason grade 4/5, serum PSA and patient age between first and second biopsy. CONCLUSIONS: With an octant biopsy regime, biochemical and pathological features of cancers detected on initial and repeat biopsy in the PSA range 2.0 to 4 ng/ml are comparable in terms of PSA, grade, stage and cancer volume suggesting identical cancer characteristics, thus advocating for a repeat prostate biopsy in case of a negative finding on initial biopsy.

Longitudinal study of men with mild symptoms of bladder outlet obstruction treated with watchful waiting for four years.

OBJECTIVES: To determine the risk of clinical progressions in men with mild lower urinary tract symptoms of bladder outlet obstruction and identify the predictors for progression in this group of men. METHODS: A total of 397 men who presented to the urology clinics with mild symptoms of bladder outlet obstruction (International Prostate Symptom Score less than 8) were analyzed in this longitudinal study conducted during a 4-year period. They began with the watchful waiting protocol and were followed up every 3 months for 48 months. Age, International Prostate Symptom Score (IPSS), divided into obstructive symptom score and irritative symptom score, serum prostate-specific antigen level, total prostate volume, transitional zone volume, urinary flow rates, and postvoid residual urine volume were documented. RESULTS: The cumulative incidence of clinical progression, defined as worsening of the IPSS with migration to the moderate symptom group (IPSS 8 to 18) or severe symptom group (IPSS 19 to 35) and an increase in IPSS of more than 2 points, was 6%, 13%, 15%, 24%, 28%, and 31% at 6, 12, 18, 24, 36, and 48 months, respectively. Nineteen patients (4.9%) developed acute urinary retention within the 48-month follow-up period. Of these 19 patients, only 2 (0.6%) required transurethral resection of the prostate. The variables of importance for disease progression in the artificial neural network analysis were, in order of statistical significance, prostate-specific antigen level, obstructive symptom score, and transitional zone volume. CONCLUSIONS: The risk for men with mild symptoms of bladder outlet obstruction to progress clinically and develop complications such as acute retention of urine is moderate. Prostate-specific antigen, obstructive symptom score, and transitional zone volume were identified as important risk factors.