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Brian R Herts

Publications and source records attributed to Brian R Herts.

At least 19 recordsLinked to original sources
PubMed2007

The role of computerized tomographic urography in the initial evaluation of hematuria.

PURPOSE: We determined the usefulness of computerized tomographic urography for the initial evaluation of patients with hematuria as an alternative to excretory urography. MATERIALS AND METHODS: A total of 259 patients (140 men and 119 women), age range 20 to 100 (mean 59.4) years, underwent computerized tomographic urography for the evaluation of hematuria and were available for followup. A cohort of 253 patients (153 men, 100 women), age range 21 to 92 (mean 57.6) years, underwent conventional excretory urography and were evaluated for comparison. RESULTS: A source of hematuria was identified in 107 patients (41.3%) in the computerized tomographic urography cohort and in 103 patients (40.7%) in the excretory urography cohort. Computerized tomographic urography alone identified a source of hematuria in 25.5% of these patients with the most commonly diagnosed lesions being renal calculi (18.9%), ureteral calculi (2.7%) and renal pelvic masses (2.3%) in the upper tract (0.94 sensitivity), and bladder masses (8.1%), prostatic abnormalities (5.4%) and inflammatory disorders (3.5%) in the lower tract (0.40 sensitivity, 0.99 specificity). The overall detection rate (19.5%), most commonly diagnosed lesions, and lower urinary tract sensitivity and specificity were similar in the excretory urography cohort. However, excretory urography exhibited a markedly lower sensitivity in detecting upper tract lesions (0.50). CONCLUSIONS: Computerized tomographic urography exhibited a significantly higher sensitivity than conventional excretory urography in detecting upper tract pathology (94.1% vs 50%). However, sensitivity for detecting lower tract lesions was low (40% or less), suggesting that computerized tomographic urography offers a comprehensive alternative to excretory urography but does not obviate the need for adjunctive cystourethroscopy for accurate evaluation of the lower urinary tract.

Female↗
PubMed2006

The predictive value of helical computed tomography for collecting-system entry during nephron-sparing surgery.

OBJECTIVES: To assess the ability of helical computed tomography (CT) including multiplanar reformatting and volume rendering (3D CT) to predict collecting system entry at surgery, as helical CT can be used to delineate renal tumour and normal renal anatomy before nephron-sparing surgery (NSS). PATIENTS AND METHODS: Knowledge of the possibility of collecting system entry during surgery might either dissuade some surgeons from NSS in elective situations or influence the operative approach or ablative technology in cases where NSS is imperative, or prepare the surgeon for the possibility of collecting system repair. We reviewed all 3D CT (349 scans) obtained before NSS at our institution over three consecutive years. Tumour size, central tumour extension, and presence of calyceal involvement were prospectively recorded at the time of 3D rendering. Collecting system entry was analysed for these three CT variables, and for three clinical variables (tumour side, size and surgical approach) collected retrospectively from the medical records. Multivariate logistic regression was used to assess the sensitivity, specificity, and positive and negative predictive values. RESULTS: Of 344 patients, 170 had collecting system entry reported at surgery. There were statistically significant associations between collecting system entry and central tumour location by CT (sensitivity 58.8%, specificity 80.5%, P < 0.001), calyceal involvement at CT (sensitivity 53.5%, specificity 78.2%, P < 0.001), and tumour size on CT of > 4 cm (sensitivity 39.4%, specificity 74.7%, P = 0.005). There were no significant associations with side or type of surgery (P > 0.83). CONCLUSION: Helical CT is a reliable predictor of calyceal entry at surgery.

Adolescent↗
PubMed2006

CT histogram analysis in pathologically proven adrenal masses.

OBJECTIVE: The purpose of this article is to evaluate a histogram analysis method for distinguishing adrenal adenomas from metastases, pheochromocytomas, and adrenocortical carcinomas on CT. MATERIALS AND METHODS: A pathology database was searched, and 335 adrenalectomies from 1995 to 2002 were identified. CT images were available for retrospective review in 187 patients (93 males, 94 females; age range, 15-84 years; mean age, 55.2 years) with 208 adrenal masses. This included 112 adenomas in 104 patients, 48 metastases in 39 patients, 40 pheochromocytomas in 36 patients, and eight adrenocortical carcinomas in eight patients. Histogram analysis was performed using a circular region of interest for mean attenuation, number of pixels, number of negative pixels (< 0 H), and percentage of negative pixels by two interpreters. Areas of necrosis were excluded from measurements. Observer agreement was calculated. RESULTS: In 72 of 76 (94.7%) and 63 of 72 (87.5%) adenomas, respectively, interpreters found attenuation values greater than 10 H contained negative pixels on unenhanced CT scans. None of the enhanced adenomas had mean attenuation less than or equal to 10 H, but 24 (38.7%) and 28 (45.2%), respectively, had negative pixels. Negative pixels were present in unenhanced and enhanced metastases, pheochromocytomas, and carcinomas. Using a 5% or 10% negative pixel threshold value to diagnose adenoma improved specificity but diminished sensitivity. Specificity for a 10% negative pixel threshold was approximately 88% for unenhanced CT scans and 99% for enhanced CT scans, with sensitivities of 71% and 12%, respectively. CONCLUSION: Although specificity for the diagnosis of adenomas on enhanced CT scans with histogram analysis was high when a 10% negative pixel threshold was used, low sensitivity likely limits clinical usefulness.

Adenoma↗
PubMed2005

Percutaneous access to upper pole renal stones: role of prone 3-dimensional computerized tomography in inspiratory and expiratory phases.

PURPOSE: We evaluated the role of noncontrast, prone position, inspiratory and expiratory 3-dimensional spiral computerized tomography (PIE-CT) for preoperative planning of percutaneous treatment in patients with complex upper pole renal calculi. MATERIALS AND METHODS: In this pilot study a total of 6 renal units in 4 women and 1 man with complex upper pole calculi who were candidates for percutaneous nephrolithotomy were evaluated with thin section PIE-CT. With the patient imaged in the prone position percutaneous access was simulated under 4 potential access conditions, including subcostal and intercostal, in inspiration and expiration. Each potential access was then deemed transpleural or extrapleural and minimally angulated or severely angulated cephalad. RESULTS: PIE-CT was performed uneventfully in all patients. Ideal nonangulated extrapleural percutaneous access was deemed possible in 5 of 6 renal units. However, inspiratory plus expiratory phases were necessary to identify the most suitable access site. In 2 renal units only 1 safe access site was identified. No pulmonary complications were noted in any of these patients. In 1 renal unit no suitable access could be identified and this patient was treated with laparoscopic caliceal diverticulectomy. CONCLUSIONS: Thin section PIE-CT offers 3-dimensionally rendered images that clearly demonstrate anatomical relationships among the kidney, calculi, pleura, diaphragm, ribs and surrounding organs. In this pilot study PIE-CT provided useful data for planning urological intervention for complex upper pole renal stones. This study also suggests that generalizations regarding the safety of upper pole access in the inspiratory or expiratory phase are not warranted.

Exhalation↗
PubMed2005

Laparoscopic partial nephrectomy for cystic masses.

PURPOSE: Although laparoscopic partial nephrectomy (LPN) has emerged as an effective treatment option in select patients with a solid renal tumor, scant data are available on cystic renal tumors. We report our experience with LPN in 50 patients with a cystic renal lesion. MATERIALS AND METHODS: Of 284 patients undergoing LPN at our institution since August 1999 preoperative computerized tomography identified a suspicious cystic lesion in 50 (17.6%) (group 1). Data were retrospectively compared with those on 50 matched, consecutive patients undergoing LPN for a solid renal mass (group 2). All patients with Bosniak II/IIF cysts were advised to undergo watchful waiting. Surgery was offered if the cyst changed in character or if that was the patient preference. RESULTS: Median tumor size was 3 cm in group 1 and 2.6 cm in group 2 (p = 0.07). Groups 1 and 2 were comparable in regard to perioperative parameters. In patients with Bosniak II (9), IIF (4), III (12) and IV (21) cysts final histopathology revealed renal cell carcinoma in 22%, 25%, 50% and 90%, respectively. All 100 patients had a negative surgical margin. No patient in group 1 had intraoperative puncture/spillage of the cystic tumor. In group 1 during a mean followup of 14 months (range 1 month to 3 years) 1 patient had retroperitoneal recurrence at 1 year despite negative surgical margins during initial LPN. CONCLUSIONS: Surgical outcomes of LPN for suspicious cystic masses are similar to those of LPN for solid tumors. However, extreme caution and refined laparoscopic technique must be exercised to avoid cyst rupture and local spillage.

Aged↗
PubMed2005

Comparison of CT findings in symptomatic and incidentally discovered pheochromocytomas.

OBJECTIVE: The objective of our study was to determine the prevalence of incidental pheochromocytomas, whether their imaging characteristics differ from those of pheochromocytomas in symptomatic patients, and whether they differ from adenomas using CT densitometry. MATERIALS AND METHODS: The records from 335 adrenalectomies performed at our institution from 1995 to 2002 were reviewed, and 71 pheochromocytomas were identified. Thirty-three patients had CT examinations performed at our institution that were available for retrospective review. From electronic and hard-copy medical records, patient age and sex, the indications for imaging, and biochemistry activity were recorded. Pheochromocytomas were classified as symptomatic or incidental on the basis of clinical presentation. These groups were compared for differences in patient age, adrenal mass volume and maximal diameter based on CT dimensions, attenuation on unenhanced CT, attenuation on enhanced CT during the portal phase, the presence of calcifications, low attenuation or cystic changes, biochemical activity, and hypertension. Statistical significance was assessed with the Student's t test or chi-square test, as appropriate. RESULTS: Nineteen incidental (57.6%) and 14 symptomatic (42.4%) adrenal pheochromocytomas were in the study. There was a significant difference between the two groups as to whether hypertension was present (incidental, 10/19 [52.6%]; symptomatic, 14/14 [100%]; p = 0.0025). We found a trend toward calcification present in more symptomatic patients (incidental, 0/19 [0%]; symptomatic, 4/14 [28.6%]; p = 0.0670). No statistically significant difference was noted in the mean patient age (incidental, 51.7 years; symptomatic, 45.9 years), mean volume of the mass (incidental, 74.0 cm(3); symptomatic, 78.2 cm(3)), mean maximal diameter of the mass (incidental, 5.26 cm; symptomatic, 5.33 cm), mean attenuation on unenhanced CT (incidental, 36.6 H; symptomatic, 34.2 H), mean attenuation on enhanced CT (incidental, 93.7 H; symptomatic, 104.3 H), necrosis score or biochemical activity (incidental, 17/18 [94.4%]; symptomatic, 12/14 [85.7%]). No attenuation value of any pheochromocytoma was less than 10 H on unenhanced CT (median, 35 H; range, 17-59 H). CONCLUSION: In our study population, 57.6% of the pheochromocytomas were incidental, more than in most reported series. A history of hypertension was more frequent in the symptomatic group (p = 0.0025), but no radiologic parameters that allow differentiation of incidental and symptomatic pheochromocytomas were found. None of the pheochromocytomas had attenuation values of less than 10 H on unenhanced CT scans.

Adrenal Gland Neoplasms↗
PubMed2005

Imaging in acute brain infarction.

Imaging in a patient suspected of having suffered an acute stroke is used primarily to clear the patient for thrombolytic therapy, by excluding intracranial hemorrhage and nonstroke causes of the patient's symptoms, within a critical 3-hour window. Noncontrast CT of the brain is the imaging test of choice for the initial evaluation of a patient with suspected acute ischemic stroke. It is rapid and readily available and has a high sensitivity for intracranial hemorrhage. Contrast-enhanced CT angiography and perfusion imaging may provide additional information with only a minimal increase in scanning time. Finally, diffusion-weighted magnetic resonance sequences have a high sensitivity for acute stroke and, with magnetic resonance perfusion imaging, may play an increasing role in the future treatment of stroke.

Aged↗
PubMed2004

Analysis of changes in attenuation of proven renal cysts on different scanning phases of triphasic MDCT.

OBJECTIVE: The purpose of this study is to document changes in attenuation values on triphasic MDCT of histologically or surgically proven cystic renal lesions. MATERIALS AND METHODS: A retrospective study of all renal lesions greater than 1 cm that underwent triphasic MDCT was performed in 90 patients before partial nephrectomy. Three reviewers independently measured the mean attenuation of all lesions in three phases (unenhanced, corticomedullary, and parenchymal) in a blinded retrospective fashion. Forty-three lesions identified at CT in 27 patients had pathologic or surgical confirmation as cysts (fluid-filled lesions). Mean change in attenuation between phases was calculated and correlated with size, unenhanced density, and percentage of the lesion exophytic from renal parenchyma. All scans were obtained after 150 mL of nonionic contrast material was injected at 3 mL/sec. Scanning delays were 30-40 sec (corticomedullary phase) and 120 sec (parenchymal phase). RESULTS: The mean change in attenuation coefficient of the cysts from the unenhanced to the parenchymal phase was -1.8 H (SD, +/- 4.4 H); from the unenhanced to the corticomedullary phase was -2.3 H (+/- 3.9 H); and from the corticomedullary to the parenchymal phase was 0.6 H (+/- 4.2 H). No cyst increased more than 10 H between the unenhanced and the parenchymal phases; more than 95% of cysts increased less than 8 H between any scanning phases. No significant difference was seen in enhancement related to lesion size (p > 0.054), unenhanced attenuation (p > 0.255), or percentage of the lesion that was exophytic (p > 0.124). CONCLUSION: The attenuation coefficient of a cystic renal lesion increased by no more than 10 H among the unenhanced, corticomedullary, and parenchymal phase scans.

Contrast Media↗
PubMed2004

CT characteristics of primary retroperitoneal neoplasms.

Primary retroperitoneal neoplasms account for only 0.1-0.2% of all malignancies. Retroperitoneal neoplasms are most commonly mesodermal, neurogenic or lymphatic in origin, with lymphoma, liposarcoma, leiomyosarcoma and malignant fibrous histiocytoma the vast majority of malignant primary retroperitoneal tumors. Although the radiographic features of retroperitoneal neoplasms often overlap, certain CT characteristics, pattern of spread and specific tumor prevalence among different demographic groups can help suggest the tumor type. CT is used to diagnosis and assess the size and extent of retroperitoneal tumors, as well as assess the involvement of organs and vasculature with resection in mind.

Humans↗
PubMed2003

Three-dimensional volume-rendered helical CT before laparoscopic adrenalectomy.

Use of three-dimensional (3D) volume-rendered helical computed tomography (CT) in surgical planning before laparoscopic adrenalectomy was evaluated in a retrospective study. In 35 consecutive patients before laparoscopic adrenalectomy, 3D volume-rendered CT scans were created from helical CT scans. Videotapes that showed anterior, lateral, posterior, and posterocephalic approaches were assessed retrospectively. The relationship (not contacting, abutting, displacing, or invading) of adrenal masses to adjacent organs (diaphragm, liver, spleen, kidneys, stomach, pancreas, and vessels) was recorded and compared with findings in surgery reports. When such findings were available, they corresponded to those in the videotape. Three-dimensional volume-rendered CT successfully displayed the relationship of adrenal masses to adjacent anatomic structures and organs before laparoscopic adrenalectomy.

Adrenal Glands↗
PubMed2003

Imaging for renal tumors.

PURPOSE OF REVIEW: The present review summarizes current developments in the imaging of renal tumors. RECENT FINDINGS: Computed tomography (CT), magnetic resonance imaging, and ultrasound are used for diagnosing, characterizing, and staging renal tumors. Recent advances have been made in many areas, but the most significant changes have occurred in helical CT. The traditional roles for CT and magnetic resonance imaging have been expanded to include the use of three-dimensional CT and magnetic resonance imaging as surgical planning tools. Three-phase CT scans are commonly performed for detection, characterization, and staging of renal lesions, but pelvic CT is probably not needed for preoperative staging. Three-phase CT scans are more sensitive for characterization and for identifying the renal vasculature. Enhancement characteristics on these scans can help to distinguish between different tumor types. Finally, CT urography is a promising alternative to conventional excretory urography, with the potential to simplify the imaging evaluation of patients with hematuria. SUMMARY: Although ultrasound and magnetic resonance imaging have many indications for imaging renal tumors, CT, with new uses and improved diagnostic capabilities, remains the gold standard in renal imaging.

Clinical Trials as Topic↗
PubMed2003

Prospective comparison of 3-dimensional volume rendered computerized tomography and conventional renal arteriography for surgical planning in patients undergoing laparoscopic donor nephrectomy.

PURPOSE: We prospectively assessed the accuracy of 3-dimensional (3-D) volume rendered computerized tomography (CT) and conventional renal arteriography to visualize renovascular anatomy in patients undergoing laparoscopic donor nephrectomy. MATERIALS AND METHODS: A total of 60 consecutive patients undergoing laparoscopic donor nephrectomy (left side in 46 and right side in 14) prospectively underwent 3-D CT and renal angiography. A short videotape of 3-D CT was prepared using volume rendering software that demonstrated the anatomical location, number, anomalies and spatial interrelationships of the renal arteries and veins. These 3-D videotapes and arteriogram findings were directly correlated with intraoperative surgical findings at laparoscopy and during ex vivo bench preparation of the harvested kidney. The perceived intraoperative value of 3D-CT to delineate renovascular anatomical detail was scored subjectively by the laparoscopic surgeon for each case on a 10-point scale of 0--completely inaccurate to 10--completely accurate. RESULTS: There were no complications related to the 3-D CT protocol and volume rendering was successful in all patients. Three-D CT accurately identified the number of renal arteries in 59 patients (98%). In 1 patient with 3 renal arteries 3-D CT and arteriogram each identified only 2. In the 46 patients undergoing left donor nephrectomy 3-D CT accurately identified the number of veins and venous anomalies in 45 (98%), including 2 with a circumaortic left renal vein. Another case of circumaortic vein was misdiagnosed as 2 renal veins. On the right side in 14 patients 3-D CT accurately identified the renal veins in 13 (94%) and missed 1 vein in a patient with 2 renal veins. Angiography correctly identified the number of renal veins in only 52 cases (87%). Furthermore, it misdiagnosed all 3 cases of circumaortic left renal vein. The laparoscopic surgeon believed that 3-D CT accurately identified the location and anatomical interrelationship of the renal vessels with precision. Mean subjective score +/- SEM was 8.5 +/- 1 for the arterial system, 8.6 +/- 1.1 for the venous system and 9.2 +/- 0.5 for any vascular anomalies. CONCLUSIONS: Three-D CT accurately identifies renal vascular anatomy in a manner that may facilitate renal hilar dissection during laparoscopic donor nephrectomy, especially during the initial surgeon experience. This imaging modality integrates essential information from angiography, venography and excretory urography into a single study, and it can obviate the need for more invasive vascular imaging in most cases.

Angiography↗
PubMed2003

Staging renal cell carcinoma with helical CT: the revised 1997 AJCC and UICC TNM criteria.

The TNM staging system for renal cell carcinoma, revised in 1997 by the UICC and AJCC, has important implications for tumor prognosis and surgical planning. Multislice helical CT of the kidneys plays a vital role in the detection, characterization, and staging of renal cell carcinoma, and for surgical planning. Radiologists should be familiar with state-of-the-art helical CT techniques, the revised TNM staging criteria, and the varied appearances of renal tumors, tumor cell types, and the wide variety of metastatic disease that occurs in advanced cases.

Carcinoma, Renal Cell↗
PubMed2002

Imaging for nephron-sparing surgery.

Nephron-sparing surgery is more technically demanding than conventional nephrectomy. The urologist can benefit from modern radiological methods to plan and monitor surgery and to provide post-surgical surveillance. This article describes how 3D volume renderings of CT and MRI data can be useful in planning nephron-sparing surgery, how intraoperative imaging can guide surgery and tumor ablation, and how CT and MRI can be used to monitor for recurrent disease and postoperative complications.

Humans↗