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K Wallner

Publications and source records attributed to K Wallner.

At least 19 recordsLinked to original sources
PubMed2001

Long-term urinary function after transperineal brachytherapy for patients with large prostate glands.

PURPOSE: To summarize longer-term postbrachytherapy morbidity in patients with prostate glands >50 cm3. METHODS AND MATERIALS: From 1997 to 1998, 33 patients with a transrectal ultrasound-based prostate volume >50 cm3 were treated at the University of Washington by 125I (144 Gy) or 103Pd (115 Gy) implantation for prostate carcinoma. These 33 patients comprised 7% of the total implant patient population. Twelve patients were treated with neoadjuvant androgen ablation before implantation. The (125)I source strength ranged from 0.34 to 0.5 mCi and the 103Pd source strength ranged from 1.1 to 1.4 mCi (pre-NIST-99). The total number of sources implanted was 94-223 (median 155). Despite the typical implant-related volume increase, the postimplant CT-defined prostate volumes were generally well-covered by the prescription isodose (median coverage 92%, range 80-100%). The preimplant urinary obstructive symptoms were quantified by the criteria of the American Urological Association. RESULTS: Of the 33 patients, 12 developed acute postimplant urinary retention, all presenting within 24 h of implantation. Patients who developed postimplant retention lasting >1 week were generally treated with intermittent self-catheterization. By 1 month, 85% of patients were catheter free. By 1 year, only 1 patient (4%) remained in urinary retention; the remainder of cases had resolved spontaneously. With follow-up of 1.7-2.6 years, the last American Urological Association scores were higher than the pretreatment scores in 15 patients and lower in 7 patients. No patient developed permanent urinary incontinence. Long-term changes in the American Urological Association scores were unrelated to whether the patient had been in urinary retention after implantation. Two patients developed rectal fistulas; they had preimplant transrectal ultrasound prostate volumes of 53 and 59 cm3, in the low range for this group of patients. No other patient had persistent rectal bleeding suggestive of clinically significant proctitis. The pretreatment serum prostate-specific antigen level was 3.3-15 ng/mL (median 7.2) and the last serum prostate-specific antigen level 0.1-1.6 ng/mL (median 0.2). CONCLUSION: Patients with larger prostate volumes appear to have moderate morbidity and a satisfactory technical outcome with brachytherapy. We do not believe the occurrence of two severe rectal complications was related to the prostate volume per se. Our experience and that of others calls into question the validity of using prostate volume as a criterion for patient suitability for prostate brachytherapy.

Brachytherapy↗
PubMed2001

Argon plasma coagulation for rectal bleeding after prostate brachytherapy.

PURPOSE: To better define the efficacy and safety of argon plasma coagulation (APC), specifically for brachytherapy-related proctitis, we reviewed the clinical course of 7 patients treated for persistent rectal bleeding. Approximately 2-10% of prostate cancer patients treated with 125I or 103Pd brachytherapy will develop radiation proctitis. The optimum treatment for patients with persistent bleeding is unclear from the paucity of available data. Prior reports lack specific dosimetric information, and patients with widely divergent forms of radiation were grouped together in the analyses. METHODS AND MATERIALS: Seven patients were treated with APC at the Veterans Affairs Puget Sound Health Care System and the University of Washington from 1997 to 1999 for persistent rectal bleeding due to prostate brachytherapy-related proctitis. Four patients received supplemental external beam radiation, delivered by a four-field technique. A single gastroenterologist at the Veterans Affairs Puget Sound Health Care System treated 6 of the 7 patients. If the degree of proctitis was limited, all sites of active bleeding were coagulated in symptomatic patients. An argon plasma coagulator electrosurgical system was used to administer treatments every 4-8 weeks as needed. The argon gas flow was set at 1.6 L/min, with an electrical power setting of 40-45 W. RESULTS: The rectal V100 (the total rectal volume, including the lumen, receiving the prescription dose or greater) for the 7 patients ranged from 0.13 to 4.61 cc. Rectal bleeding was first noticed 3-18 months after implantation. APC (range 1-3 sessions) was performed 9-22 months after implantation. Five patients had complete resolution of their bleeding, usually within days of completing APC. Two patients had only partial relief from bleeding, but declined additional APC therapy. No patient developed clinically evident progressive rectal wall abnormalities after APC, (post-APC follow-up range 4-13 months). CONCLUSIONS: Most patients benefited from APC, and no cases of clinically evident progressive tissue destruction were noted. Although APC appears to be efficacious and safe in the setting of the rectal doses described here, caution is in order when contemplating APC for brachytherapy patients.

Argon↗
PubMed2001

Short-term sexual function after prostate brachytherapy.

Sexual function was evaluated in 34 patients with low-risk prostate cancer (PSA < or = 10, Gleason score < or = 6, clinical stage T1/T2) undergoing brachytherapy in a phase III prospective randomized trial comparing iodine-125 ((125)I) to palladium-103 ((103)Pd). The mean and median International Index of Erectile Function (IIEF) scores for the entire group were 14.2 and 16.5, respectively, and there was no difference between these scores when stratified by isotope. IIEF scores < 6, 6 to 11, and > or = 12 were recorded in 35% (12/34), 6% (2/34), and 59% (20/34) of patients, respectively. Hematospermia, orgasmalgia (pain at the time of orgasm), and alteration in intensity of orgasm were documented in 26% (9/34), 15% (5/34), and 38% (13/34) of patients, respectively, but these side effects were of limited duration for most patients. There was no relationship between radiation dose to the neurovascular bundles (NVB), which averaged 209% of the prescribed prostate dose, and the development of postbrachytherapy impotence. All four impotent patients who used sildenafil responded favorably. With a median follow-up of 13 months, 65% of patients undergoing prostate brachytherapy maintained sexual function without pharmacologic support. Including sildenafil responses, 76.5% of patients sustained erections sufficient for sexual intercourse.

Aged↗
PubMed2001

Temporary PSA rises and repeat prostate biopsies after brachytherapy.

PURPOSE: The long-standing confusion regarding the clinical relevance of postimplant biopsies is complicated by the common occurrence of temporary PSA rises between 1 and 2 years after brachytherapy. We report here 4 patients with temporary, self-limited PSA rises and postimplant biopsies, for whom radical prostatectomy was strongly advised but for whom surgery would probably have been the wrong choice. MATERIALS AND METHODS: Transperineal I-125 or Pd-103 implants were performed as previously described. After implantation, patients were followed routinely, with repeat PSA and physical examination at approximately every 4 to 6 months. Timing of postimplant PSAs was at the discretion of the patient and his doctors. Postimplant biopsies were performed in all cases out of concern for a persistently elevated serum PSA. Sections of fixed and embedded tissue were stained with standard hematoxylin and eosin. RESULTS: All 4 patients presented here were advised to have a salvage prostatectomy based primarily on their PSA changes. However, all of the patients have subsequently had a dramatic PSA fall, consistent with long-term cancer control, despite the fact that 3 of the 4 had histologic evidence of persistent cancer on repeat prostate biopsy. CONCLUSIONS: It is crucial that clinicians be aware of the potential for the doubly confusing situation of temporary PSA rises and apparently positive rebiopsies and the pressure it puts on both patients and their physicians to go ahead with inappropriate salvage therapy.

Adenocarcinoma↗
PubMed2001

A comparison of radiation dose to the bulb of the penis in men with and without prostate brachytherapy-induced erectile dysfunction.

PURPOSE: To retrospectively evaluate the relationship between the radiation dose to the bulb of the penis and the development of erectile dysfunction (ED) in patients undergoing permanent prostate brachytherapy without external beam radiation therapy. METHODS AND MATERIALS: Twenty-three men who developed ED after transperineal ultrasound-guided permanent prostate brachytherapy for clinical T1/T2 adenocarcinoma of the prostate gland were paired with 23 similar men who maintained potency after implantation. Potency was defined as an erection sufficient for vaginal penetration. The mean and median follow-up for the entire group was 34.6 +/- 13.7 months and 32.8 months, respectively. Patients were implanted with either (125)I (145 Gy TG-43) or (103)Pd (115 Gy, pre-NIST-99). No patient received external beam radiation therapy either before or after brachytherapy. The bulb of the penis was outlined at 0.5-cm intervals on the Day 0 postimplant CT scan. The radiation dose distribution to the bulb of the penis was defined in terms of the minimal dose delivered to 25%, 50%, 70%, 75%, 90%, and 95% of the bulb (D(25), D(50), D(70), D(75), D(90), and D(95)). RESULTS: The radiation dose delivered to the bulb of the penis in men with postbrachytherapy-induced ED was statistically greater for all evaluated dosimetric parameters (D(25), D(50), D(70), D(75), D(90), and D(95)). Multivariate analysis indicated that dose to the bulb of the penis and patient age at the time of implant were predictive of postimplant ED, whereas choice of isotope had no effect. Among potent patients, 19/23 had D(50) < or = 40% of prescribed minimal peripheral dose, whereas for the impotent patients, 19/23 had D(50) >40% of the minimal peripheral dose. Of the impotent patients, 17 utilized sildenafil, with 15 experiencing a favorable response (88%). CONCLUSION: Our data suggest that prostate brachytherapy-induced impotence is highly correlated with the radiation dose delivered to the bulb of the penis. With Day 0 dosimetric evaluation, the radiation dose delivered to 50% of the bulb of the penis should be maintained at 50 Gy or less to maximize post-treatment potency. Fortunately, the majority of the brachytherapy-induced ED population responds favorably to sildenafil.

Adenocarcinoma↗
PubMed2001

Standardization of prostate brachytherapy treatment plans.

PURPOSE: Whereas custom-designed plans are the norm for prostate brachytherapy, the relationship between linear prostate dimensions and volume calls into question the routine need for customized treatment planning. With the goal of streamlining the treatment-planning process, we have compared the treatment margins (TMs) achieved with one standard plan applied to patients with a wide range of prostate volumes. METHODS AND MATERIALS: Preimplant transrectal ultrasound (TRUS) images of 50 unselected University of Washington patients with T1-T2 cancer and a prostate volume between 20 cc and 50 cc were studied. Patients were arbitrarily grouped into categories of 20-30 cc, 30-40 cc, and 40-50 cc. A standard 19-needle plan was devised for patients in the 30- to 40-cc range, using an arbitrary minimum margin of 5 mm around the gross tumor volume (GTV), making use of inverse planning technology to achieve 100% coverage of the target volume with accentuation of dose at the periphery and sparing of the central region. The idealized plan was applied to each patient's TRUS study. The distances (TMs) between the prostatic edge (GTV) and treated volume (TV) were determined perpendicular to the prostatic margin. RESULTS: Averaged over the entire patient group, the ratio of thickness to width was 1.4, whereas the ratio of length to width was 1.3. These values were fairly constant over the range of volumes, emphasizing that the prostate retains its general shape as volume increases. The idealized standard plan was overlaid on the ultrasound images of the 17 patients in the 30- to 40-cc group and the V100, the percentage of target volume receiving 100% or more of the prescription dose, was 98% or greater for 15 of the 17 patients. The lateral and posterior TMs fell within a narrow range, most being within 2 mm of the idealized 5-mm TM. To estimate whether a 10-cc volume-interval stratification was reasonable, the standard plan generated from the 30- to 40-cc prostate model was applied to 5 patients each from the 20- to 30-cc group and the 40- to 50-cc group. Using the standard plan designed for the 30- to 40-cc group, the TMs were closer to 10 mm than to 5 mm for the smaller volume glands and too small for the larger volume ones, assuming an ideal margin of 5 mm. CONCLUSION: The application of standardized plans to prostate brachytherapy is feasible. Stratifying the volume in 10-cc intervals appears to be adequate, suggesting that the majority of cases appropriate for treatment with brachytherapy might be treated with three standard plans. While the authors believe that the use of a limited number of standard treatment plans is feasible, practical, and medically acceptable, it should be emphasized that the use of a standard plan should always be previewed by computer-aided application to the particular patient's planning images.

Brachytherapy↗
PubMed2001

Preexisting histologic evidence of prostatitis is unrelated to postimplant urinary morbidity.

The presence and extent of prostatitis on the patients' preimplant biopsy slides was correlated with their postimplant course to determine if any relationship exists between histological prostatitis and postimplant morbidity. Biopsy slides from 56 patients treated with I-125 (144 Gy, TG-43), Pd-103 (125 Gy, NIST-1999), or Pd-103 plus supplemental external beam radiation (20-44 Gy) were studied. As part of ongoing prospective protocols, treatment-related morbidity is monitored by mailed questionnaires at 1, 3, 6, 12, and 24 months postimplant, using standard American Urologic Association (I-PSS) and Radiation Therapy Oncology Group criteria. Patient's preimplant biopsies, stained with standard hematoxylin and eosin, were retrieved for review by one uropathologist (LT). Separate evaluations of the degree and extent of inflammation in biopsy cores free of cancer and in cancerous biopsy cores were undertaken. Infiltrates were classified as periglandular if they were within 50 microns of a glandular structure. They were otherwise classified as stromal. Distribution of the inflammation was reported as focal, multifocal, or diffuse. The intensity of inflammation was separately graded as mild if there were fewer than 10 inflammatory cells per high-power field, moderate if there were 10-200 cells per high-power microscopic field, or severe if there were more than 200 cells per field. In all cases the great majority of inflammatory cells were mononuclear, predominantly lymphocytes. Periglandular inflammation was most common, with 18% of patients having focal periglandular and 20% having multifocal periglandular inflammation on their preimplant biopsies. Cancer-related infiltrates were the second most common, with 23% of patients having focal, 13% multifocal, and 13% diffuse cancer-related inflammation on their preimplant biopsies. Eight of the 55 patients developed postimplant urinary retention, requiring catheterization for 2 to 8 days. The overall incidence of postimplant urinary retention was low and there was no obvious relationship between the presence of inflammation on preimplant biopsy and the likelihood of postimplant urinary retention. AUA score changes at 1 and 6 months postimplant were highly variable and unrelated to the presence or severity of periglandular or cancer-related inflammation. Considering the apparent lack of relationship between histological findings and clinical outcomes in the patients reported here, the authors conclude that histologic evidence of prostatitis is not a contraindication to brachytherapy.

Biopsy↗
PubMed2001

Adventitial remodeling after angioplasty is associated with expression of tenascin mRNA by adventitial myofibroblasts.

OBJECTIVES: The purpose of this study was to determine the temporospatial expression of tenascin-C (TnC) in balloon-injured rat and porcine arteries. BACKGROUND: Recent studies suggest that cell migration, in addition to cell proliferation, is a critical component of neointima formation after vascular injury. We have previously shown that adventitial myofibroblasts synthesize growth factors that contribute to the formation of neointima after arterial injury. We have also shown that the extracellular matrix protein, TnC, regulates cell migration. Consequently, we investigated the temporospatial expression of TnC by myofibroblasts after vascular injury. METHODS: In situ hybridization and immunohistochemistry were used to investigate the temporospatial expression of TnC in injured arteries. Northern and Western blots were used to determine the in vitro expression of TnC. RESULTS: In situ hybridization revealed that the major site of TnC expression early after vascular injury was the adventitial myofibroblasts. Immunohistochemical staining demonstrated that TnC expression began in adventitial myofibroblasts three days after injury. Tenascin-C expression, however, did not persist in this region. Rather, it moved progressively across the vascular wall toward the luminal surface. By one week, TnC expression reached the developing neointima. In vitro, myofibroblasts did not express TnC mRNA under basal conditions. In contrast, angiotensin II and PDGF-BB, factors that have been implicated in remodeling of balloon-injured arteries, markedly upregulated TnC mRNA. CONCLUSIONS: Tenascin-C is expressed in response to balloon injury. Tenascin-C expression begins with adventitial myofibroblasts. Over a period of 7 to 14 days, expression moves progressively across the vessel wall to the neointima. We hypothesize that adventitial myofibroblasts are actively involved in the formation of neointima and that TnC facilitates migration of these cells during adventitial remodeling.

Angioplasty, Balloon↗
PubMed2001

Improved outcomes with radiation for prostate cancer.

During the last 15 years, a series of substantial technical improvements have occurred in external beam radiation and brachytherapy. The introduction of PSA-based posttreatment monitoring has allowed a reasonable comparison between each radiation modality and prostatectomy. Such comparisons show more similarities than differences. Probably the most exciting finding in regard to curing cancer is that higher-risk patients have a more favorable prognosis than previously recognized using higher doses now achievable with either form of radiation.

Humans↗
PubMed2001

Patient reported complications after prostate brachytherapy.

PURPOSE: Prostate brachytherapy has gained popularity due partly to the low rates of short-term complications shown in studies from highly select clinical practices. These series rely on medical records generated by the treating physician and are prone to underreport complications. We summarize the complication reports obtained directly from patients to establish a more realistic incidence of treatment related problems. MATERIALS AND METHODS: In 1997, 160 consecutive patients treated with prostate brachytherapy at the University of Washington were studied. A questionnaire was designed to determine the rate of complications occurring within 1 year of the procedure. The questions were formulated for ease of use and conciseness, while accounting for easily recalled events associated with complications. A total of 147 (92%) patients completed the questionnaire. RESULTS: There were 8 (5%) patients who required hospital admission for an average of 2 days (range 1 to 7) as a result of the procedure. A total of 56 (38%) patients required nonroutine visits with a physician in an office setting or at an emergency room. Radiation proctitis diagnosed by endoscopy developed in 8 (5%) patients but no one needed surgical intervention. A total of 47 (32%) patients required urinary catheterization at some point after implantation. CONCLUSIONS: We demonstrated a higher rate of short-term complications than those previously reported. Fortunately, the majority of side effects were self-limited and no treatment related mortality or cardiovascular morbidity was seen. Our findings may provide a more realistic account of the complications likely to occur after implantation than might be surmised from previous reports.

Adult↗
PubMed2000

Corneal macrophage infiltrates following ocular herpes simplex virus type 1 challenge vary in BALB/c mice vaccinated with different vaccines.

Macrophage cell infiltrates in the cornea were examined following ocular herpes simplex virus type 1 (HSV-1) challenge of vaccinated BALB/c mice. Mice were vaccinated with individual HSV-1 glycoproteins, cocktails of different HSV-1 glycoproteins, or live avirulent HSV-1 (strain KOS). Cryostat sections of cornea were taken at different times after challenge and reacted with M1/70, F4/80, BM8, or MOMA-1 monoclonal antibodies. The pattern of macrophage responses in the cornea differed depending on the vaccine that was given prior to HSV-1 ocular challenge. No macrophage response was detected in mice vaccinated with the highly protective 5gPs consisting of the five glycoproteins gB, gC, gD, gE, and gI. In contrast, mock vaccinated mice and mice vaccinated with gK, which is known to exacerbate HSV-1 induced eye disease, had high sustained macrophage responses. Mice vaccinated with 7gPs (5gPs+gG and gH) had moderate levels of macrophages. It appeared that (1) the most effective vaccines induced no detectable infiltrating macrophages in the eyes, while the least efficacious vaccines had very high levels of infiltrating macrophages; (2) presence of CD11b(+) cells in the cornea appeared to correlate with enhanced blepharitis, but did not appear to affect corneal scarring; and (3) presence of F4/80(+) cells in the cornea tended to correlate with increased corneal scarring.

Animals↗
PubMed2000

Transperineal brachytherapy in patients with large prostate glands.

The purpose of this study is to help clarify the use of prostate size as a selection factor for prostate brachytherapy. From 1997 to 1998, 33 patients with a TRUS-based prostate volume greater than 50 cc were treated at the University of Washington by I-125 (144 Gy) or Pd-103 (115 Gy) implantation for prostatic carcinoma. These 33 patients comprised 7% of the total implants performed. Each patient underwent a preimplant TRUS study in the lithotomy position, taking serial axial images of the prostate at 0.5 cm intervals from the base of the gland to the apex. The contours on the preimplant TRUS images were used to calculate the prostate volumes reported here. Only one patient received supplemental external beam irradiation prior to implantation. Twelve patients were treated with neoadjuvant androgen ablation prior to implantation. The prostate volumes quoted here are those taken after hormonal downsizing. Postimplant axial CT images were digitized to calculate the CT-based target coverage. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association. Each patient was contacted at the time of this article preparation to update postimplant morbidity information. In all cases, at least 80% of the postimplant volume was covered, despite a median implant-related volume increase of 15%. Five of the 33 patients' postimplant CT scans showed some degree of incomplete target coverage of the anterior/lateral prostate margin. There was no clear association between inadequate anterior/lateral coverage and the degree of interference. Twelve of the 33 patients developed acute postimplant urinary retention, all occurring within 24 hr of implantation. Within this group of 33 patients with a large prostate volume, there was no relationship between the likelihood of acute or chronic urinary retention and preimplant prostate size or obstructive symptoms. Patients who developed postimplant retention lasting more than one week were generally managed by intermittent self-catheterization. By one month, 85% of patients were catheter-free. Based on the data reported here, we are more inclined to accept patients with a large prostate for implantation without insisting on preimplant size reduction. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 199-205 (2000).

Brachytherapy↗
PubMed2000

Prostate brachytherapy in patients with median lobe hyperplasia.

Our aim was to document the technical and clinical course of prostate brachytherapy patients with radiographic evidence of median lobe hyperplasia (MLH). Eight patients with MLH were identified during our routine brachytherapy practice, representing 9% of the 87 brachytherapy patients treated during a 6-month period. No effort was made to avoid brachytherapy in patients noted to have MLH on diagnostic work-up. Cystoscopic evaluation was not routinely performed. Postimplant axial computed tomographic (CT) images of the prostate were obtained at 0.5 cm intervals. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association (AUA). Each patient was contacted during the writing of this report to update postimplant morbidity information. There was no apparent association between the degree of MLH and preimplant prostate volume or AUA score. Intraoperatively, we were able to visualize MLH by transrectal ultrasound and did not notice any particular difficulty placing sources in the MLH tissue or migration of sources out of the tissue. The prescription isodose covered from 81% to 99% of the postimplant CT-defined target volume, achieving adequate dose to the median lobe tissue in all patients. Two of the eight patients developed acute, postimplant urinary retention. The first patient required intermittent self-catheterization for 3 months and then resumed spontaneous urination. MLH does not appear to be a strong contraindication to prostate brachytherapy, and prophylactic resection of hypertrophic tissue in such patients is probably not warranted. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 152-156 (2000).

Aged↗
PubMed2000

Brachytherapy radiation doses to the neurovascular bundles.

PURPOSE: To investigate the role of radiation dose to the neurovascular bundles (NVB) in brachytherapy-related impotence. METHODS AND MATERIALS: Fourteen Pd-103 or I-125 implant patients were studied. For patients treated with implant alone, the prostate and margin (clinical target volume [CTV]) received a prescription dose of 144 Gy for I-125 or 115 Gy for Pd-103. Two patients received Pd-103 (90 Gy) with 46 Gy supplemental external beam radiation (EBRT). Axial CT images were acquired 2 to 4 hours postoperatively for postimplant dosimetry. Because the NVBs cannot be visualized on CT, NVB calculation points were determined according to previously published anatomic descriptions. Bilateral NVB points were considered to lie posterior-laterally, approximately 2 mm from the prostatic capsule. NVB doses were recorded bilaterally, at 0.5-cm intervals from the prostatic base. RESULTS: For Pd-103, the average NVB doses ranged from 150 Gy to 260 Gy, or 130% to 226% of the prescription dose. For I-125, the average NVB dose ranged from 200 Gy to 325 Gy, or 140% to 225% of the prescription dose. These was no consistent relationship between the NVB dose and the distance from the prostatic base. To examine the possible effect of minor deviations of our calculation points from the true NVB location, we performed NVB calculations at points 2 mm medial or lateral from the NVB calculation point in 8 patients. Doses at these alternate calculation points were comparable, although there was greater variability with small changes in the calculation point if sources were located outside the capsule, near the NVB calculation point. Three patients who developed early postimplant impotence had maximal NVB doses that far exceeded the average values. CONCLUSIONS: In the next few years, we hope to clarify the role of high NVB radiation doses on potency, by correlating NVB dose calculations with a large number of patients enrolled in an ongoing I-125 versus Pd-103 trial for early-stage patients, for whom detailed dosimetric and potency data are being collected prospectively. In the future, we anticipate that NVB doses may be incorporated into dosimetry guidelines to maximize tumor control and minimize treatment-related morbidity.

Brachytherapy↗
PubMed2000

Colocalization of tenascin and sympathetic nerves in a canine model of nerve sprouting and sudden cardiac death.

INTRODUCTION: Sympathetic nerve sprouting after myocardial infarction (MI) may contribute significantly to the occurrence of ventricular arrhythmia and sudden cardiac death. Tenascin-X (TnX), a matrix protein known to be associated with nerve growth in central and peripheral nerves, also may play a role in cardiac nerve sprouting after MI. METHODS AND RESULTS: Immunocytochemical staining techniques were used to identify nerves in 5-microm serial sections from 6 normal dogs and 11 dogs with MI. Among the dogs with MI, 4 also received nerve growth factor infusion to the left stellate ganglion. The time between MI to tissue harvest averaged 35.7 +/- 14.4 days. Tyrosine hydroxylase (TH) stain was used to identify sympathetic nerves, and growth-associated protein-43 (GAP-43) was used to identify growing nerves. Polyclonal antibody was obtained for use in identifying TnX. Nerves were evident in both the infarcted and noninfarcted areas. Many nerves were found around blood vessels. A total of 181 nerves in 69 slides were examined: 89 were from noninfarcted myocardium, 4 from infarct, 13 from infarct border zone, and 75 from perivascular regions. Except in normal dogs, all nerves stained positive for TH also stained positive for GAP-43, indicating sympathetic nerve sprouting after MI. In all dogs, the nerves that stained positive for TH also stained positive for TnX. CONCLUSION: There is a colocalization of TnX, GAP-43, and TH in sprouted cardiac nerves. These results suggest that TnX is important not only in the existing normal myocardial nerve cells but also in cardiac sympathetic nerve sprouting after MI.

Animals↗
PubMed2000

Brachytherapy in patients with small prostate glands.

PURPOSE: To better define the role of small prostate volume in selecting patients for brachytherapy. MATERIALS AND METHODS: Thirty patients with a transrectal ultrasound (TRUS)-based prostate volumes less than 20 cc were treated at the University of Washington by permanent isotope implantation for prostatic carcinoma. Preimplant TRUS studies were taken at 0.5-cm intervals from the base of the gland to the apex. Planning margins of 1 to 5 mm were added to the prostatic margins, and sources were routinely planned to be placed as much as 5 mm outside of the prostatic margin. The prescription dose was 144 and 115 Gy for full-dose iodine 125 and palladium 103 monotherapy, respectively. For patients receiving supplemental external-beam irradiation, the implant doses were 120 and 90 Gy for 125I and 103Pd, respectively. The morning following the implant, axial computed tomographic (CT) images of the prostate were obtained at 0.5-cm intervals with patients in the supine position. Follow-up ranged from 11 to 28 months (median 21 months). RESULTS: The median coverage of the postimplant prostate volume by the prescription dose was 92%. To calculate the incidence of source migration, the number of sources placed at the time of implant was compared with the number identified on postimplant CT scan. The median number of sources implanted was 84 (range 65-103) compared to an average of 82 identified postoperatively, which is consistent with a source migration rate of two. A median of 31 sources appeared to be outside of the prostatic margins, as identified on postimplant CT scan (range 14-53). Of the 23 patients contacted at the time of this report, one had developed acute postimplant urinary retention that resolved within 2 weeks of implantation. At last follow-up, patient pre- and postimplant AUA scores were not substantially different, with the median AUA score increasing from 7 (range 2-21) to 8 (range 1-27). CONCLUSIONS: Patients with small prostate volumes appear to have acceptable morbidity and target coverage with prostate brachytherapy. Based on the data reported here, we do not believe that a small prostate volume in itself is a contraindication to brachytherapy.

Brachytherapy↗
PubMed2000

Cystourethroscopic findings before and after prostate brachytherapy.

PURPOSE: To assess the role of cystourethroscopy in predicting the risk of postimplant urinary retention. MATERIALS AND METHODS: Fifteen unselected prostate brachytherapy patients implanted with 125I or 103Pd under spinal or general anesthesia were studied. Following induction of anesthesia, the patient was placed in the lithotomy position and cystourethroscopy performed using a 17 sheath and a 30 degrees lens. Irrigation pressure was 100-cm water. A photograph was taken from the level of the verumontanum. At completion of the implant procedure, a second cystourethroscopy was performed and another photograph taken. The degree of obstruction was rated using a 3-point scale. Each patient was contacted at the time of this report to update postimplant morbidity information with follow-up from 1 to 10 months. RESULTS: The patients' preimplant cystourethroscopic findings ranged from minimal to complete occlusion. There was no clear relationship between the American Urologic Association (AUA) score or preimplant prostate volume and the degree of obstruction. Nearly all patients had some increased physical obstruction following completion of the procedure, but only 8 of 14 patients had an increase in obstruction grade. Six patients were completely obstructed at the completion of the implant procedure, only one of whom developed urinary retention. CONCLUSIONS: Marked variability in cystourethroscopy findings do not appear to have a strong influence on the likelihood of postimplant urinary retention and are not a reliable predictor of retention.

Brachytherapy↗