PubMed Health⌕ Search

Biomedical subjects

P K Hol

Publications and source records attributed to P K Hol.

9 recordsLinked to original sources
PubMed2001

[Cryoablation--a treatment option for inoperable liver tumors?].

BACKGROUND: Most patients with primary and secondary liver tumours are inoperable by conventional surgery. This has prompted the development of different techniques of local destruction of liver tumours, i.e. cryosurgical ablation radiofrequency, laser, and microwave ablation. MATERIAL AND METHODS: On the basis of relevant literature and our own experience we describe the principles of local destruction by cryoablation of colorectal metastases. RESULTS: Indications for ablation are mainly colorectal metastases and hepatocellular carcinoma. Mechanisms for tumour destruction include intra- and extracellular ice crystal formation, cellular membrane rupture, cellular dehydration and ischaemic damage. Ablation is regularly monitored by ultrasonography, which is suboptimal because of inadequate visualisation of the iceball. Long-term outcome of local destruction of liver tumours is not documented and randomized trials are not ethically acceptable. This complicates analyses of patient outcomes. INTERPRETATION: Local ablation of liver tumours is experimental therapy and should only be performed as a part of prospective trials.

Carcinoma, Hepatocellular↗
PubMed2001

Magnetic-resonance-guided percutaneous cryoablation of hepatic tumours.

OBJECTIVE: To study the feasibility of percutaneous cryoablation of hepatic tumours monitored by magnetic resonance imaging (MRI). DESIGN: Prospective study SETTING: University hospital, Norway PATIENTS: Six patients with hepatic metastases from colorectal cancer. INTERVENTIONS: Percutaneous cryoprobe positioning under general anaesthesia. Positioning and freezing monitored by near-real-time MRI using an open 0.5 Tesla MRI configuration system. MAIN OUTCOME MEASURES: Safety and feasibility of the procedure. Measurement of volumes of cryolesions. RESULTS: One patient developed a biliary leakage that had to be drained. Four patients developed pleural fluid. Two small tumours were adequately cryoablated. In the remaining 4 patients with large (>4 cm) tumours, an adequate cryolesion could not be formed. Cryolesion volumes larger than 105 cm3 were not produced even using 3-4 probes. MRI visualised the growing cryolesion well, but positioning of the cryoprobes was time-consuming. CONCLUSION: MR guided cryoablation is clinically feasible and gives good visualisation of the procedure. Patients with small tumours (<3 cm) seem to be best suited to this percutaneous approach as cryolesion volumes claimed to be adequate for tumour destruction can be produced. Measurement of tumour volume preoperatively may help to select patients who will respond.

Aged↗
PubMed2001

Graft control by transit time flow measurement and intraoperative angiography in coronary artery bypass surgery.

BACKGROUND: The aim of this study was to compare the relationship between intraoperative transit time flow measurements and angiographic findings with long-term graft patency in 72 patients who underwent coronary artery bypass surgery. METHODS: Transit time flow measurements with recording of mean flow and pulsatility indexes were performed after completion of the anastomoses. Coronary angiography was performed on-table while the patients were still in general anesthesia, and then at follow-up three months and 12 months after surgery. Based on angiography, the grafts were graded as type A (fully patent), type B (having more than 50% diameter reduction), or type O (occluded). RESULTS: Of the 67 left internal mammary artery (LIMA) grafts, 51 (76%) were type A on-table, 14 (21%) were type B, and two (3%) were type O. Of the 57 saphenous vein grafts, 49 (86%) were type A, 7 (12%) were type B, and one (2%) was type O. For both LIMA and vein grafts, there were no differences in flow (p = 0.69 and 0.47, respectively) or pulsatility index (p = 0.79 and 0.83) between type A and B. There were also no differences in flow (p = 0.37 and 0.7) or pulsatility index (p = 0.37 and 0.24) between type B on-table that either normalized or persisted occluded at the follow-up. Transit time flow measurement failed to detect an occluded LIMA graft as shown by intraoperative angiography. CONCLUSIONS: Blood flow measurements performed intraoperatively could not identify significant lesions in arterial or vein grafts, and could not predict graft patency. We have become cautious in interpreting flow measurements alone and combine blood flow recordings with intraoperative angiography in the assessment of graft quality.

Aged↗
PubMed2000

MRI-guided celiac plexus block.

Celiac plexus block is used as a palliative procedure in cases of severe upper abdominal pain caused by pancreatitis or tumors of the pancreas. It can be guided by bony landmarks, fluoroscopy, ultrasound (US), or computed tomography (CT). To avoid severe complications, methods visualizing soft tissue, like CT and magnetic resonance (MR) imaging, are preferable. We describe celiac plexus blocks carried out in an open MR scanner, offering needle guidance with an optical tracking system and near real-time image acquisition. Eight patients with severe chronic abdominal pain were included. In these, 14 celiac blocks were carried out. Good or total pain relief was achieved in 8 of the 14 blocks (57%), a moderate effect in 5 blocks (36%), and no effect in 1 block (7%). The placement of the needle was easily guided with MR in all cases. The MR technique ensures good visualization of soft tissue, direct monitoring of needle movement and avoids exposure to ionizing radiation. Celiac plexus block can safely be carried out in an open MR scanner.

Abdominal Pain↗
PubMed1997

[Cerebral CT findings in AIDS].

A cerebral CT was performed in 82 of 525 AIDS patients, with positive findings in 46 cases. These findings included cerebral atrophy in 28 cases, pathological demyelinisation in two, progressive multifocal leukoencephalopathy in one, toxoplasmosis in 11, lymphomas in seven, infarction in one and one subdural haematoma. The radiological findings are correlated to pathology and clinical symptoms. The authors point out the importance of these findings for correct interpretation of the CT scans.

AIDS Dementia Complex↗
PubMed1992

[Intraoperative ultrasonography in brain surgery].

Intraoperative ultrasound was used in 33 patients. 19 lesions were primary malignant brain tumours, including 12 gliomas, three astrocytomas and four oligodendrogliomas. There were five metastases, three meningeomas, two dysembryoplastic neuroepithelial tumours and two angiomas. One patient had an arachnoid cyst, and another an infarct. The main advantage of carrying out intraoperative ultrasound examination is that it helps to localize the tumour, particularly in small subcortical lesions where the brain surface may appear normal. Ultrasound is less useful for characterizing the tumour, although the various tumours do show some differences. As a rule, the glioblastomas are inhomogeneous and poorly marginated, while low grade gliomas are more homogeneous and well marginated. Also meningeomas and metastases tend to be homogeneous and well marginated. Periofocal oedema is hyperechogenic compared with brain tissue, with an intensity between that of normal brain tissue and tumour mass. Cyst, calcification and haemorrhage are easily demonstrated.

Adenocarcinoma↗
PubMed1990

Axial and appendicular bone mineral content determined by computed tomography. Relationship to age and body size in males.

Bone density and mass related values were determined in femoral condyles and in the second lumbar vertebra in males of middle age. A poor agreement was found between measurements in the two locations. The measurements were compared with age and body size by means of correlation analysis and multiple regression analysis. There was a significant linear relationship between lumbar measures and age (beta coefficient -0.61 and -0.75) while the relationship with age for the femoral measures was less (beta -0.36 and -0.45). For all measurements there was a poor correlation with body size (weight, length and surface area). Bone mineral content measurements in the lumbar and appendicular skeleton have different clinical implications. When selecting a method for estimating the bone mineral content careful attention must be paid to what type of information is wanted and whether the method is adequate for that particular purpose.

Aging↗
PubMedDate not supplied

Demonstration of pedal arterial arcades in occlusive arteriosclerotic disease. Conventional and digital subtraction angiography compared.

Conventional arteriography, intraarterial digital subtraction angiography (DSA), and intravenous DSA were used in the evaluation of the patency of the pedal arterial arcades in 15 patients with advanced peripheral arteriosclerotic disease. Intraarterial DSA was found to be superior to conventional arteriography. In 12 of 15 patients, excellent or good results were achieved by intraarterial DSA compared with 5 or 15 patients examined by conventional arteriography. All intravenous DSA studies performed in 6 patients were classified as poor.

Aged↗