Detailed plaque texture analysis as the alternate method of ultrasound image analysis in predicting the risk of intraoperative microembolism and perioperative complications.

BACKGROUND: The aim of the study was to assess the value of an alternative method of carotid plaque ultrasound image analysis in relation to the perioperative complications and the main risk factor: the microembolism (ME). MATERIAL AND METHODS: 96 plaques were evaluated following carotid endarterectomy. Preoperatively, each plaque was screened by ultrasound and assessed by means of 2 computer assisted methods. All patients were evaluated for ME (measured as hits) intraoperatively. The removed plaques were assessed visually (intraoperative assessement) and histologically. A number of risk factors were included as a final outcome event for the purpose of multivariate regression analysis. RESULTS: Detailed plaque texture analysis (DPTA) predicts best the risk of perioperative complications and ME (p = 0.029 and p = 0.028 respectively). The results of the standard gray-scale median (GSM) analysis did not reach the statistical significance (p > 0.1). The predictive value of the model (ROC) was 0.88. The multivariate model for ME revealed that from the level of > 5 HITS, a rapid increase in the risk of perioperative complications (rise of 5% by every 1 hit) is seen and correlates well with the DPTA. ROC was 0.77. A direct correlation between the DPTA and perioperative ME was shown. CONCLUSIONS: DPTA analysis of a carotid plaque is more predictive of the likelihood of microembolism than the GSM analysis. There is a direct correlation between the perioperative ME and plaque morphology, as assessed by DPTA. This supports the need for further refinements in noninvasive analysis of carotid plaques.

Carotid plaque texture analysis can predict the incidence of silent brain infarcts among patients undergoing carotid endarterectomy.

OBJECTIVE: To evaluate the correlation between microembolism (ME) and incidence of silent brain infarcts during carotid endarterectomy. MATERIALS AND METHODS: Patients were assessed using transcranial Doppler, carotid ultrasound and pre- and postoperative magnetic resonance imaging (MRIs). The clinical status, need for shunt insertion and significant decrease in the blood flow in the middle cerebral artery were recorded. All data were analysed using multivariate regression models. RESULTS: Out of the 76 patients examined, 17 (22%) had new postoperative lesions seen on MRI. Three of them (4%) were symptomatic, 14 (18%) were asymptomatic. The multivariate regression models showed that ME is a potent predictor of "silent" ischemic brain lesions, at p<0.001 (OR [95% CI]-1.1 [1.05, 1.2]). Digital plaque texture analysis predicted ME (p=0.028; OR [95% CI]-0.32 [0.12, 0.89]). The risk of ME increases steadily with the decrease in the echogenicity of the plaque. CONCLUSIONS: ME is a potent predictor of "silent" ischemic brain lesions among patients with carotid stenosis. An analysis of plaque texture can predict the degree of ME during endarterectomy and is more precise than the standard GSM.

[Assessment of cerebrovascular reserve capacity in patients with carotid artery disease using transcranial Doppler sonography and acetazolamide]. / Ocena mózgowej rezerwy naczyniowej u chorych z zespolem tetnic szyjnych przy pomocy przezczaszkowej ultrasonografii dopplerowskiej oraz acetazolamidu.

AIM: In our study we utilised transcranial Doppler sonography (TCD) and the test with intravenously administered acetazolamide (reversible inhibitor of carbonic anhydrase) which causes vasodilatation of the brain resistance vessels to assess cerebrovascular reserve capacity (CVRC) in patients with symptomatic and asymptomatic carotid stenosis. MATERIAL: 25 patients (22 male, 3 female; aged 46-82; mean 62 years) with carotid artery disease were examined. They were qualified for the operation because of that. METHOD: Blood flow wave spectrum in the right and left middle cerebral artery (MCA) was analysed. 2 MHz pulsed-wave transducer was placed over the appropriate temporal acoustic window. We measured mean blood flow velocity (Vmean) in both MCAs. The records were taken: a) at rest, b) 15 minutes after 1.0 g of acetazolamide was administered intravenously. Cerebrovascular reserve (CVRC) was calculated as the maximal percentage increase in the appropriate MCA after the administration of acetazolamide in comparison with its value at rest. The values of CVRC were analysed statistically. RESULTS: 15 minutes after acetazolamide was injected CVRC was 44 +/- 15% (mean +/- SD) (range 0-74) in asymptomatic hemispheres. In 30 patients (97%) CVRC was 46 +/- 12% (23-74) and in 1 patient (3%) 0% (case nr 7). In the group of symptomatic hemispheres CVRC was 12 +/- 15% (-16-36) after acetazolamide administration. In 12 patients (63%) from this group CVRC was positive: 20 +/- 11% (3-33), in 4 patients (21%) CVRC was 0% (cases nr 8, 9, 22, 23) and in other 3 patients (16%) CVRC was negative: -7 +/- 8 (-16(-)-3) (cases nr 4, 12, 19). CONCLUSION: 1. The group of patients with symptomatic hemispheres have statistically lower CVRC in comparison with the group of asymptomatic hemispheres. 2. There was no statistical difference between the mean values of CVRC in patients with bilateral, severe carotid stenosis and the ones with unilateral changes. 3. We believe that such a test performed by means of TCD and intravenously injected acetazolamide can indicate a subgroup of patients with carotid stenosis for whom carotid endarterectomy is necessary at the earliest time because of possible early neurological complications appearance which are related to the lack or serious impairment of CVRC.

[Acute bowel obstruction: up-to-date surgical problem]. / Ostra niedroznosc przewodu pokarmowego--wciaz aktualny problem chirurgiczny.

Authors present their own experience in surgical management of patients with acute bowel obstruction. They analyse etiology and methods of treatment. Over 50% of acute bowel obstruction cases were incarcerated hernias. Primary resection was performed in over 50% of cases caused by colonic cancer.

Evaluation of blood flow velocity changes in middle cerebral artery from contralateral transorbital approach as the alternative method of monitoring during carotid surgery in patients with no temporal acoustic "window".

BACKGROUND: We evaluated the possibility of utilising the transorbital approach for middle cerebral artery (MCA) blood flow velocity monitoring as the alternative method of intraoperative evaluation of cerebral ischaemia risk in patients with no temporal acoustic "window". METHODS: We insonated the MCA from contralateral, transorbital approach at a depth ranging from 68 to 80 mm. Ten patients with no temporal window (group A) undergoing carotid surgery were examined intraoperatively by means of this method. RESULTS: For comparison a reference group of 15 patients with temporal acoustic windows present (group B) was established. In this group, the simultaneous (double) records of MCA blood flow velocity changes from transtemporal and transorbital approaches during carotid endarterectomy (CEA) were conducted. Mean blood flow velocity (Vmean) was recorded after anaesthesia, during a 120-sec clamp test, after shunt insertion (if necessary), immediately after and 5 min after clamp release. CONCLUSIONS: We would recommend transorbital Doppler monitoring as a method of choice when the transtemporal approach is not possible. Although quite difficult, this method appears to be safe and reliable in the intraoperative evaluation of patients at risk of cerebral ischaemia.

[Does intraoperative transcranial doppler monitoring improve results of carotid endarterectomy?]. / Czy sródoperacyjne monitorowanie przeplywu w tetnicy mózgu srodkowej metoda przezczaszkowego dopplera moze poprawic wyniki endarterektomii tetnic szyjnych?

UNLABELLED: We evaluated the role of intraoperative transcranial Doppler sonography in improvement of carotid endarterectomy results. We analyzed the outcome of 38 carotid endarterectomies (CEA) performed in 22 female and 16 male patients with symptomatic carotid stenosis, aged between 43 and 78 years (av. 61.8 years). Constant measurements of peak and average velocity (Va) were taken during following stages of CEA:-after anaesthesia--during 120 s crossclamp test, -after shunt insertion (5 patients),-immediately after and 5 min after crossclamp release. RESULTS: We obtained following values of Va in particular stages of CEA:-after anaesthesia 0.54 m/s (0.38-1.08),-during 120 s crossclamp test 0.25 m/s (0.12-0.58),-after shunt insertion 0.47 m/s (0.32-0.78),-immediately after crossclamping 0.72 m/s (0.51-1.40),-5 min. after crossclamp release 0.62 m/s (0.42-1.27). In 2 cases no blood flow velocity increase was found after shunt insertion. The immediate correction of shunt positioning was done. In 2 other patients no hemodynamic effect after CEA was detected (no blood flow velocity increase in MCA and at the same time, no neurological impairments were noticed). After quick investigation inferior carotid artery kinking above the arteriotomy site and its stenosis after suturing were found. Both of these abnormalities were removed and since that moment the blood flow velocity in MCA increased, in comparison with preoperative values. CONCLUSIONS: intraoperative transcranial doppler monitoring 1) allows to identify any kind of blood flow disturbance in MCA during each stage of CEA which appears before neurological impairment, 2) gives the possibility of shunt functioning evaluation, 3) enables to avoid intraoperatively unpredictable situations that may result in imminent cerebral ischemia, 4) 70% decrease of blood flow velocity in MCA is the indication for shunt insertion, 5) proved to be very helpful in (in 10% of our material) improving the results of all carotid endarterectomies.

[Pheochromocytoma with hemorrhagic necrosis and rupture with symptoms of acute abdomen and shock]. / Pheochromocytoma--martwica krwotoczna i przerwanie guza z objawami ostrego brzucha i wstrzasem.

A case of a pheochromocytoma with haemorrhagic necrosis resulting in signs of acute abdomen with shock is reported. Diagnosis of a ruptured adrenal tumor was made by CT scanning. Elevated urine and plasma catecholamines as well as histological examination of the removed tumor confirmed the clinical suspicion of pheochromocytoma. The patient made uneventful recovery and is asymptomatic 2 years after surgery. Ruptured pheochromocytoma as a cause of abdominal emergency is discussed in view of the existing literature.

Collateral role of the external carotid artery and its branches in occlusion of the internal carotid artery.

In 40 patients with unilateral occlusion of the internal carotid artery, using a transcranial Doppler device, blood flow velocity in the ipsilateral ophthalmic and middle cerebral artery was registered. During compression of the ipsilateral common carotid artery a decrease of ophthalmic artery flow velocity was noted in 39 patients (97.5%) and a decrease of middle cerebral artery flow velocity in 8 patients (20%). The average decrease of mean velocity in the middle cerebral artery was 4.5% of the initial value. During compression of the ipsilateral superficial temporal and facial arteries ophthalmic artery flow velocity decreased in 10 patients (25%) and no marked decrease of middle cerebral blood flow was noted. Conclusions. The external carotid artery in most of the patients with internal carotid occlusion is of no significance for cerebral blood supply, but it is the most important source of collateral blood supply to the eye. The maxillary artery, and not superficial temporal and facial as it seemed in periorbital Doppler examinations, is the branch of the greatest collateral value for the eye and brain.

[Recanalization of occlusion of the peripheral segment of the femoral artery by the Kensey method]. / Rekanalizacja niedroznego obwodowego odcinka tetnicy udowej sposobem Kenseya.

The aim of the presented study was to analyse the surgical technique and results of recanalization of the peripheral segment of iliac artery with Kensey's technique. Altogether 16 patients were operated. Arterial patency was observed in 14 patients immediately after surgery. This number decreased to 11 after a 3-month follow-up. Complications in the form of perforation of the arterial wall, hemorrhage at the site of puncture and thrombotic lesions in the reconstructed arterial channel were seen in 4 cases. Authors' own experience suggests that Kensey's technique together with laser surgery are the treatment of choice in case of iliac arterial occlusion in patients, in whom classic surgery is contraindicated.

[Vision disorders as the first symptom of cerebrovascular insufficiencycaused by the changes in the carotid arteries. Studies using the transcranial Doppler ultrasonic apparatus TC2-64B]. / Zaburzenia widzenia jako pierwszy objaw niedostatecznosci ukrwienia mózgu spowodowanego zmianami w tetnicach szyjnych. Badania przy zastosowaniu transcranial Doppler TC2-64-B.

Investigations were carried out in 25 patients with carotid arteries changes. A 2 MHz head was used. Direction of the flow, the average speed and index of pulsation were determined. The results were compared with examinations in 13 healthy subjects. Disturbances of vision were shown by 11 patients (44 p.c.). A normal direction of blood perfusion was observed in 8 arteries (25 p.c.), a reversed one in 22 (69 p.c.), in 2 patients no Doppler's signal could be obtained. In arteries with a reversal flow of blood the authors observed the maximal mean speed and the lowest pulsation index. In neither case did the ophthalmological examinations reveal any embolic material. It seems that visual disturbances in patients with carotid arteries changes may be caused by a change of direction of the blood flow from a normal to a reversed one.

Intrapericardial pheochromocytoma: a case report.

A patient with a pheochromocytoma located intrapericardially is described. 131I-labeled metaiodobenzylguanidine scintigraphy was helpful in locating the tumour. The operation and postoperative course were uneventful.

[Ultrasonic noninvasive examination of the human cerebrovascular system using the vascular impedance method]. / Ultradzwiekowa nieinwazyjna diagnostyka ukladu naczyniowo-mózgowego czlowieka, metoda wejsciowej impedancji naczyniowej.

The authors employed input vascular impedance measurements, based on the non-invasive ultrasound measurements of blood flow and pressure in common carotid artery, to evaluate human cerebro-vascular system. An analysis involved a 4-element substitute model of vascular system which included: compliance, inertia, vascular resistance, and peripheral resistance. Preliminary clinical examination of both sick and healthy individuals indicate that total real resistance measured in the common carotid artery depends on the patency of branching arteries. At the same time, ratio of vascular resistance Ro do peripheral resistance Rp may be an indicator of the atheromatous lesions to the arteries below measurement point. Ratio Ro greater than 0.5 is being considered as an index of pathology.

Surgical treatment of renal ischemia and renovascular hypertension.

The results of treatment in patients with very advanced renovascular hypertension are presented. The patients were divided into two groups. In group one were patients with only one kidney and renovascular hypertension. The risk of operation and special precautions are discussed. Group two included patients with kidney non-function due to renal artery occlusion and severe hypertension. All these patients were candidates for nephrectomy. During the operation in some of them, the technical possibilities for vascular reconstruction were found. Instead of nephrectomy aortorenal bypasses were done.

Late results of Linton flap operation.

Linton flap operation was performed in 202 patients with postphlebitic syndrome complicated by evident ulceration 64% of patients were followed up for 1-14 years. Complete cure was obtained in 87.7%.