Biomedical subjects

Bernhard Kramann

Publications and source records attributed to Bernhard Kramann.

6 recordsLinked to original sources

PubMed2003

Angiography for acute lower gastrointestinal hemorrhage: efficacy of cut film compared with digital subtraction techniques.

PURPOSE: To find out if digital subtraction angiography (DSA) has a different diagnostic power than conventional cut-film angiography in investigating acute lower gastrointestinal (GI) hemorrhage. MATERIALS AND METHODS: Retrospective analysis of two cohorts of patients investigated by angiography for acute lower GI hemorrhage was performed. One group of patients treated at one center ("hospital H") underwent conventional angiography. The other patients, treated at another center ("hospital G"), were investigated exclusively by DSA. The groups were compared for demographic characteristics, etiology, and bleeding parameters. The diagnostic power of both angiographic modalities was compared and statistically analyzed. RESULTS: Fifty-five lower GI hemorrhages investigated by conventional cut-film angiography and 53 cases studied by DSA were included. Both study groups had statistically similar demographic and bleeding characteristics. Overall sensitivity, specificity, and positive and negative predictive values of cut-film angiography for localizing the lower GI bleeding were 62%, 73%, 86%, and 42%, whereas, for DSA, the respective values were 60%, 100%, 100%, and 24% (Z-test P values were.78,.02,.03, and.16). CONCLUSIONS: DSA is as sensitive as conventional cut-film angiography for localizing acute lower GI bleeding. If a lesion is found, the chance that it will be the bleeding source is higher with DSA than with conventional angiography.

Acute Disease↗

PubMed2003

Early posttransplantation renal allograft perfusion failure due to dissection: diagnosis and interventional treatment.

OBJECTIVE: The aim of our study was to describe the role of interventional radiology, especially in the use of vascular stents, in early renal perfusion failure after transplantation. CONCLUSION: Angiography revealed intimal dissection of the graft artery and graft venous thrombosis, which were successfully treated with stent angioplasty and thromboaspiration. For early vascular complication after transplantation, timely use of angiography and subsequent intervention should be recognized as potentially effective and safe treatment techniques.

Aged↗

PubMed2002

Athlete's heart: right and left ventricular mass and function in male endurance athletes and untrained individuals determined by magnetic resonance imaging.

OBJECTIVES: Athlete's heart represents a structural and functional adaptation to regular endurance exercise. BACKGROUND: While left ventricular (LV) hypertrophy of the athlete's heart has been examined in many studies, the extent of right ventricular (RV) hypertrophy is still uncertain because of its complex shape and trabecular structure. To examine RV hypertrophy, we used magnetic resonance imaging (MRI) and hypothesized that athlete's heart is characterized by similar LV and RV hypertrophy. METHODS: The LV and RV mass, volume, and function in 21 male endurance athletes (A) (27 +/- 4 years; 70 +/- 8 kg; 178 +/- 7 cm; maximal oxygen uptake [VO(2)max]: 68 +/- 5 ml/min per kg) and 21 pair-matched untrained control subjects (C) (26 +/- 3 years; 71 +/- 9 kg; 178 +/- 6 cm; VO(2)max: 42 +/- 6 ml/min per kg) were analyzed by MRI (Magnetom Vision 1.5T, Siemens, Erlangen, Germany). RESULTS: Left ventricular masses: (A: 200 +/- 20 g; C: 148 +/- 17 g) and RV masses (A: 77 +/- 10 g; C: 56 +/- 8 g) differed significantly between the groups (p < 0.001). The LV and RV end-diastolic volumes (EDV) (LV-EDV 167 +/- 28 ml [A]; 125 +/- 16 ml [C]; RV-EDV 160 +/- 26 ml [A]; 128 +/- 10 ml [C]), and stroke volumes (SV) (LV-SV: 99 +/- 18 ml [A], 74 +/- 11 ml [C]; RV-SV: 102 +/- 18 ml [A], 79 +/- 8 ml [C]) were significantly different between the athletes and control subjects (p < 0.001), whereas ejection fractions (EF) (LV-EF: 59 +/- 3% [A]; 59 +/- 6% [C]; RV-EF: 63 +/- 3% [A], 62 +/- 3% [C]) and LV-to-RV ratios were similar for both groups (LV-to-RV mass: 2.6 +/- 0.2 [A], 2.6 +/- 0.3 [C]; LV-to-RV EDV: 1.05 +/- 0.14 [A], 0.99 +/- 0.14 [C]; LV-to-RV SV: 0.98 +/- 0.17 [A], 0.95 +/- 0.17 [C]; LV-to-RV EF: 0.93 +/- 0.07 [A], 0.96 +/- 0.10 [C]). CONCLUSIONS: Regular and extensive endurance training results in similar changes in LV and RV mass, volume, and function in endurance athletes. This leads to the conclusion that the athlete's heart is a balanced enlarged heart.

Adolescent↗

PubMed2002

Arterial embolization of a secondary aneurysmatic bone cyst of the thoracic spine prior to surgical excision in a 15-year-old girl.

We report on a 15-year-old girl with a secondary aneurysmatic bone cyst of the thoracic spine with extension into the spinal canal on the basis of an osteoblastoma. Surgical treatment was facilitated by preoperative embolization of the highly-vascular tumor. Excision of the tumor was performed without extensive intraoperative blood loss. Following excision, transpedicular-stabilization of the spinal column was achieved using a fixateur intern. We conclude that superselective embolization of benign lesions of the spinal column constitutes a feasible means of reducing intraoperative bleeding complications, thus enhancing resectability.

Adolescent↗

PubMed2002

Nonionic contrast media iohexol and iomeprol decrease renal arterial tone: comparative studies on human and porcine isolated vascular segments.

RATIONALE AND OBJECTIVES: The vasoconstriction of the renal arteries is frequently considered as a crucial factor for radiocontrast-induced nephropathy. A direct effect of iodinated radiographic contrast medium (RCM) on vascular smooth muscle is supposed to be one component of the vascular response. We studied the effect of the nonionic RCM iomeprol and iohexol on the tonus of isolated human and porcine renal arteries in vitro. METHODS: In an organ bath renal arterial rings, uncontracted or precontracted by 10 micromol/L phenylephrine were incubated with increasing concentrations (15-103 mg iodine/mL) of iohexol, iomeprol, and mannitol solution isoosmolar to the contrast media. In a part of the preparations the endothelium was destroyed. Human vessels were obtained from tumor nephrectomy specimens of 10 patients. RESULTS: In human experiments iomeprol and iohexol (P < 0.05) relaxed renal arterial rings whereas mannitol produced concentration-dependent contractions. The relaxation by both contrast media was slightly attenuated upon increasing their concentration. The differences between mannitol solutions and RCM were statistically significant (P < 0.001) at concentrations of 57 mg iodine/mL and higher. Precontracted rings were significantly stronger relaxed by the RCM compared with mannitol (P < 0.001). The contrast medium induced relaxation did not depend on the presence of an intact endothelium (P > 0.05). Experiments with renal arterial segments prepared from swine showed similar results, with stronger relaxations than the human preparations. CONCLUSION: Iomeprol and iohexol relaxed isolated renal arterial segments. These observations are in contradiction with the hypothesis that contrast media induce nephropathy by a direct vasoconstrictive effect on vascular smooth muscle. They do not exclude, however, a reduction of renal blood flow by other factors like liberation of hormones.

Animals↗

PubMed2001

MRI of penile fracture: diagnosis and therapeutic follow-up.

A rupture of corpus cavernosum (CC) is a rare injury of the erect penis. The present study describes the role of MRI for diagnosis and follow-up of this injury. Four patients with clinically suspected acute penile fractures underwent MRI. Imaging findings were confirmed at surgery. In three patients, follow-up MRI was also available at 1, 6 and 16 weeks after surgical repair. In all patients pre-contrast T1-weighted images (T1WI) clearly disclosed ruptures of CC, which depicted as discontinuity of low signal intensity of the tunica albuginea (TA). Concomitant subcutaneous haematoma were well visualised both on T1-weighted (T1WI) and T2-weighted images, whereas haematoma in CC were optimally demonstrated on contrast-enhanced T1WI. On follow-up MRI all fractures presented similar healing process. Shortly after the repair, the tunical suture showed an increase in signal intensity on pre-contrast T1WI and was strongly enhanced with the administration of contrast material. Then the tear site gradually recovered low signal intensity on all spin-echo sequences by 4 months after surgery. These serial findings may suggest the formation of vascularised granulation tissue during cicatrisation. Magnetic resonance imaging is of great value for the diagnosis and follow-up in patients with penile fracture.

Adult↗