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T Rizk

Publications and source records attributed to T Rizk.

18 recordsLinked to original sources
PubMed1999

[Temporary occlusion in surgical management of intracranial aneurysm. Report of 54 cases].

Temporary arterial occlusion (TAO) is commonly used in the surgery of intracranial giant aneurysms. Its usefulness and safety in the surgical management of all cases of aneurysms remains to be proved. We report a series of 54 patients operated on for an intracranial aneurysm with the use of TAO. Among the 27 patients, admitted before the 4th day following post subarachnoid hemorrhage with I or II on WFNS score clinically, 24 had early aneurysm surgery. The size of the aneurysm was small in 16 cases, medium in 22, large in 13 and giant in 3 cases. The protocol proposed by Batjer in 1988 for large and giant aneurysms (etomidate, normotention and hypervolemia) was used without any electrophysiological monitoring. All patients underwent a post-operative cerebral CT scan to evaluate the incidence of a cerebral ischemia. Serial transcranial doppler was used to evaluate the severity of vasospasm. Clinical results were assessed using the GOS. TAO was elective in 51 patients and done after peroperative aneurysm rupture in 3 patients. The duration of TAO was less than 5 mn in 25 patients, between 5 and 10 min in 12, between 10 and 15 in 11, between 15 and 20 in 5 and more than 20 min in one patient. The last one developed a reversible neurological deficit secondary to ischemia attribuated to TAO. Intracranial aneurysm peroperative rupture was noted in 3 patients, clinical vasospam in 13 patients. These results allow us to recommend the routine use of TAO in the surgery of intracranial aneurysm. When application time is limited and cerebral protection used, TAO is safe. It decreases the risk of intraoperative rupture from a 18% rate in literature to 4.2% in our present experience and the risk of symptomatic vasospasm is not increased.

Adult↗
PubMed1996

Cerebral oligodendrogliomas in children: an analysis of 15 cases.

The cases of 15 children operated on for cerebral pure oligodendroglioma were studied. Two groups of children were distinguished. Group I children presented with epilepsy (7 cases); their tumor was histologically benign in all cases. These children are all alive after a median follow-up of 72 months: however, 2 of them presented with a local recurrence, which was operated on, and are actually disease-free. Group 2 children presented with intracranial hypertension (8 cases); the tumor was anaplastic in 7 cases. Despite postoperative radiotherapy and chemotherapy 6 children died; their median survival time was 17 months. The present series shows the existence of a clear correlation between clinical presentation, histological grading and survival in childhood cerebral oligodendrogliomas.

Adolescent↗
PubMed1995

[Cerebrovascular reactivity to CO2 during general anesthesia maintained with either isoflurane-N2O or propofol-N2O. A comparative study by transcranial Doppler velocimetry].

OBJECTIVES: To compare, using transcranial doppler velocimetry (TDV), the cerebral blood flow velocity and CO2 reactivity during general anaesthesia maintained with either isoflurane-N2O-O2(IF) or propofol-N2O-O2 (PF) in adults with a normal brain. STUDY DESIGN: Nonrandomized controlled trial. PATIENTS: Forty ASA I patients (mean age 41 +/- 13 yrs, 15 F/35 M) undergoing surgery of the lumbar spine in prone position. The first 20 were allocated into the IF group and the subsequent 20 into the PF group. METHODS: General anaesthesia was induced with midazolam (0.05 mg.kg-1), phenoperidine (0.03 mg.kg-1), thiopentone (5 mg.kg-1), vecuronium (0.1 mg.kg-1) and maintained with N2O (50 vol %) and O2 (50 vol %) and either isoflurane (0.8 < Fet < 1 vol %) in IF group or propofol (6 mg.kg-1.h-1) in PF group. The vascular reactivity was assessed with velocimetry measurements (Angiodine DMS, with a probe transmitting a 2-MHz pulsed wave) of flow in the middle cerebral artery at a given PetCO2 (obtained by adjustments of VT) during systole (SV) and diastole (DV). Three measurements were made: at T1 (PetCO2 = 30 +/- 2 mmHg), at T2 (PetCO2 = 40 +/- 2) and at T3 (PetCO2 = 30 +/- 2 mmHg). RESULTS: In the IF group, VS increased by +32% at T2 (P = 0.006) with an increase of + 3.4 %/1 mmHg of PetCO2. Similarly, in the PF group VS increased by + 31 % at T2 (P < 0.0001) with an increase of 2.9 %/1 mmHg of PetCO2. In both groups the VS returned to baseline values at T3. In the IF group, VD increased by + 66% at T2 (P < 0.0001), with an increase of + 7%/1 mmHg of PetCO2. Similarly in the PF group, VD increased by + 61% (P < 0.0001) with an increase of + 5.7%/1 mmHg of PetCO2. In both groups the VD returned to baseline values at T3. CONCLUSIONS: During anaesthesia maintained with either isoflurane-N2O-O2 or propofol-N2O-O2, a change in PetCO2 results in similar changes in VS and VD. These anaesthetic agents preserve the cerebrovascular reactivity of the normal brain. The results of this study are in accordance with those obtained with other reference techniques in healthy volunteers. Transcranial doppler velocimetry can be a useful noninvasive tool of clinical research in neuroanaesthesia.

Adult↗
PubMed1994

[Malignant astrocytoma of the cerebellum. Apropos of 10 cases. Review of the literature].

While reviewing a series of 138 cerebellar tumors operated upon between 1978 and 1991, the authors could only find 2 glioblastomas and 8 anaplastic astrocytomas, occurring in 4 children (3 to 14 years old) and 6 adults (23 to 48 years old). These 10 cases represent 2% of the all malignant gliomas population observed during the same period of time. Clinically speaking, nothing makes these tumors different from other cerebellar ones. However, with an heterogenous image and an irregular contrast enhancement, the CT (scan) appearance can lead to the diagnosis. 7 lesions develop within the cerebellar vermis (vermis cerebelli) and 3 develop within the cerebellar hemisphere. Total surgical resection is performed in 9 cases and subtotal resection in 1 case (because of the extension to the floor of the fourth ventricle). Adjunctive radiotherapy on their posterior cranial fossa is achieved in 8 cases. The 2 patients with a glioblastoma present with a recurrence of their tumor at 15 months and 6 years respectively, and eventually died. Out of the patients with an anaplastic astrocytoma, 4 are still alive without recurrence and with a median follow-up of 7 years. The pathogenesis of such lesions is discussed. An aggressive therapeutic management is suggested because of the possible prolonged survival rate.

Adolescent↗
PubMed1994

Are the calcium antagonists really useful in cerebral aneurysmal surgery? A retrospective study.

From 1983 to 1990, 234 patients with one or several cerebral arterial aneurysms were surgically treated in our department. Since 1983, we have been performing surgery as early as possible. As soon as the subarachnoid hemorrhage diagnosis is confirmed by computed tomography (or if unconfirmed, by lumbar puncture), we assume that each patient may have an aneurysm. Between 1987 and 1990, 111 patients were treated by vascular volume expansion (maintenance of central venous pressure above 5 cm H2O with 4% albumin or Ringer-lactate or, if necessary, with 20% albumin), which we supplemented with calcium antagonists (nimodipine in 60 patients and nicardipine in 51 patients). Two months after being discharged, each patient is examined by a neurosurgeon and, on the same day, is subjected to a neuropsychological evaluation and a computed tomographic scan of the brain. A few months after this consultation, a working-position/family-activities questionnaire is issued to the patient. All of the results studied on the basis of postoperative mortality, second-month computed tomographic scan ischemia, neuropsychological evaluation, and return to work show no significant difference between the groups with or without calcium antagonists or between the nimodipine and nicardipine subgroups.

Activities of Daily Living↗
PubMed1993

ED1-containing cellular fibronectin release into lung lymph during lung vascular injury with postoperative bacteremia.

Fibronectin (Fn) exists in both a soluble and insoluble form. Soluble Fn in plasma and lymph is an opsonic molecule that enhances phagocytic host defense. Insoluble Fn in the subendothelial and extracellular matrix is an adhesive molecule that mediates cell adhesion to substratum. The extracellular matrix of tissues such as the lung contains a mixture of both plasma-derived fibronectin (pFn) as well as locally synthesized cellular fibronectin (cFn). cFn is antigenically related to pFn, but cFn has extra domains (ED1 and ED2) that do not exist in liver synthesized pFn. The purpose of this study was to determine whether ED1-Fn was released into lung lymph before an increase in lung vascular permeability following postoperative bacteremia. Male sheep (n = 8) with surgically prepared lung lymph fistulae were infused intravenously with a sublethal dose (5 x 10(8)) of Pseudomonas aeruginosa 2 days following surgery. Lymph flow (QL), lymph-to-plasma (L/P) total protein ratio, lung protein clearance (QL x L/P), and hemodynamics were measured over 48 h following bacterial challenge. The lymph and plasma ED1-Fn concentrations were determined by enzyme-linked immunosorbent assay (ELISA) using a murine monoclonal antibody specific to the ED1 region of human cFn. There was a rapid rise of ED1-Fn flux in lung lymph which was evident 60 min after the start of bacterial infusion, resulting in a maximum three- to fourfold increase (P < 0.05) in this parameter. In contrast, the ED1-Fn concentration in plasma before bacterial infusion was less than lung lymph and it did not increase over the initial 6 h following bacterial infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Osteosarcoma of the sacrum. Apropos of a case in a 14 year-old girl].

The authors report a case of sacral osteosarcoma, which is a rare and dreaded tumor. Sciatica was the first manifestation. Patients with refractory sciatica and normal plain films and computed tomography studies of the lumbar spine should undergo magnetic resonance imaging to look for a sacral lesion.

Adolescent↗
PubMed1993

[Giant ependymoma of the cauda equina. Long-term development apropos of 7 cases].

Seven cases of giant ependymomas of cauda equina, extending from the conus medullaris to the sacrum, are reported. Mean age of the patients was 36 years. The initial symptoms were not specific, including low back pain and radiculalgias. However, in two cases, the clinical presentation was related to hydrocephalus. At the time of the operation, 6 patients presented with pain, weakness and sphincter dysfunction. The diagnosis of tumor was made after myelogram in all cases. Metrizamide enhanced CT scan has been performed in one case. None patient had preoperative magnetic resonance imaging (MRI) but MRI allowed the follow up in 5 patients and detection of local and remote recurrences in 4 cases. All the tumors were attached to the filum terminale, and unless extended from L2 to S1. Pathologically, 3 patients had tumors classified as myxopapillary and 4 of the cellular type. Two patients had gross total resection of the tumor at the initial operation. Five patients had initial biopsy to make a diagnosis and required subsequent surgery for radical excision after an average of 16.8 months. Radiation therapy has been performed in 1 case after biopsy, in 1 case after total resection (grade III) and in 2 cases after recurrences. Three patients died 1 year, 5 years, 12 years post-operatively. Among these 3 patients, 2 had recurrences. Four patients are alive. One patient has no recurrence 5 years after initial surgery. Another patient remains symptom free 7 years after surgery but MRI showed a local recurrence. The last two patients present recurrences 7 years and 8 years after surgery. These recurrences have been treated by surgical removal.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[Are calcium channel blockers really useful in cerebral aneurysm surgery?].

Two retrospective series of early operated cerebral arterial aneurysms are compared. One series involves 74 patients treated from 1983 to 1987 by vascular volume expansion only. The other series involves 75 patients treated from 1987 to 1990 by vascular volume expansion associated by calcium antagonists (nimodipine or nicardipine). The conclusion is that in our experience, calcium antagonists do not improve the outcome (mortality, cognition findings and return to work) obtained by vascular volume expansion alone. Moreover they put forward that there is no difference between the patients treated by nimodipine and those treated by nicardipine.

Calcium Channel Blockers↗
PubMed1992

Recurrent intrinsic brain stem epidermoid cyst.

The authors report the case of a 14-month-old baby boy with an epidermoid cyst located entirely within the pons and medulla, without an exophytic component. The lesion was examined by computed tomography and magnetic resonance imaging. The child was operated upon three times after two recurrences of the lesion. A suboccipital, subtonsillar approach was used for the first and second procedures and a transtemporal approach for the last one. Excision was thought to be complete the first time, since a solid tumor was found and removed in a large cyst. The cyst wall was not identified. No tumor was found during the second procedure despite recurrence of the cyst, which was drained without an attempt to remove the cyst wall. Finally the cyst recurred with a large tumor in the cyst wall which was again totally removed. Consistent with the high mortality of brain stem epidermoid cysts in the literature, the child eventually died. The therapeutic problems, surgical options, and consequences are discussed.

Brain Stem↗
PubMed1991

Using a saphenous vein branch for a patch.

The majority of vascular surgeons find that the autologous saphenous vein is the conduit of choice for femoropopliteal and femorotibial bypasses. The branches of the saphenous vein are eventually ligated but can serve several useful purposes, such as completing an angiogram, passing a valvulotome, or widening the anastomosis. Another use for the branches consists of using the branch as a patch when the vein needs to be reopened, i.e., for thrombectomy, during the postoperative period. This is done by making a venotomy adjacent to a branch. The surgical technique, as practiced by us, is described and illustrated by a schematic diagram.

Humans↗
PubMedDate not supplied

[Stereotaxic approach in deep cerebral lesions].

The authors report a retrospective study (April 92-April 95) of 60 CT guided stereotactic biopsies. The procedure offered accurate histological diagnosis in 56 cases. There were 38 glial tumors, the majority being of high grade (III-IV). Five abscesses were evacuated and medically treated. Complications occurred in 5% of cases. These results are compatible with those reported in the literature. The simplicity and accuracy of stereotactic procedure are confirmed, making it an imperative step in the management of intraxial space occupying lesion when surgical resection is negotiable. The other applications of the stereotactic procedure are exposed.

Adolescent↗
PubMedDate not supplied

[Intracranial arterial aneurysm: from diagnosis to treatment. A retrospective study of 46 surgically treated cases].

The authors report a series of 46 patients operated for an intracranial aneurysm from January 92 to January 96 in Hôtel-Dieu de France. There were 28 males and 18 females ranging from 22 to 69 years. Forty-four patients presented a typical clinical pattern of subarachnoid haemorrhage. In 20 cases (45%), correct diagnosis was not made at the time of bleeding but at another outpatient visit or at a bleeding recurrence. Cerebral angiography was performed in all our patients. The most frequent aneurysmal location was at the anterior communicating artery (n = 20). Surgical total exclusion of the aneurysm was possible in 45 patients. Forty-one patients had a favourable outcome but three presented important neurological sequelae. We encountered 2 postoperative deaths due to irreversible arterial vasospasm. These results suggest that the preoperative neurological state and the occurrence of an arterial vasospasm are the main prognostic factors of the intracranial aneurysm. Early diagnosis and treatment allow to avoid rebleeding, mostly responsible of the poor neurological status, and to better manage the arterial vasospasm in order to improve the outcome.

Adult↗