Biomedical subjects

U Ozkan

Publications and source records attributed to U Ozkan.

16 recordsLinked to original sources

PubMed2004

Histopathologic changes in oculomotor nerve and ciliary ganglion in aneurysmatic compression injuries of oculomotor nerve.

BACKGROUND: Bilateral common carotid artery ligation (BCCAL) increases vertebrobasilar blood flow and leads to increased luminal pressure, luminal enlargement, wall thinning, convolutions and sometimes aneurysm formation in posterior circulation arteries, especially the posterior communicating arteries (PcomA). PcomA aneurysms compress the oculomotor nerves. The principal aim of this investigation is to examine the histopathologic results of the compressive effect of PcomA aneurysms on the oculomotor nerves (OMN) and on ciliary ganglions (CG). METHODS: When we observed the effects of BCCAL on the posterior circulation arteries of the brain in fifteen ligated rabbits after sacrifice, we noticed aneurysm formation on these arteries in three rabbits. These aneurysms developed on the PcomAs compressed the oculomotor nerves. These compressed nerves and normal oculomotor nerves together with their ciliary ganglions were examined histopathologically. RESULTS: A PComA aneurysm developed in three rabbits from 15 ligated animals and these aneurysms compressed the oculomotor nerves on the same side. Partial peripheral necrosis and axonal loss were seen on the compressed oculomotor nerves. Concomitantly, cellular loss and necrosis were also observed on their ganglions. CONCLUSION: Bilateral common carotid artery ligation may lead to PcomAs and these aneurysms could compress the oculomotor nerves. Compression injuries of oculomotor nerve may cause cellular injury and necrosis on both oculomotor nerves and ciliary ganglions.

Animals↗

PubMed2003

Prevention of spinal epidural fibrosis by recombinant tissue plasminogen activator in rats.

STUDY DESIGN: A randomized-controlled experimental study was conducted to investigate the effectiveness of recombinant tissue plasminogen activator (rt-PA) on postlaminectomy epidural fibrosis in rats. SETTING: Diyarbakir, Turkey. METHODS: In a rat model, allowing objective histopathological quantification, the postoperative epidural scar formation was investigated and the potential of local rt-PA in preventing the production of epidural fibrosis was assessed. Rats were randomly allocated to local rt-PA (12 rats) or control (12 rats). RESULTS: Findings suggest a beneficial effect of rt-PA in decreasing the epidural fibrosis following laminectomy when compared with control groups for all investigated parameters such as intermuscular scar (P=0.04), middle scar (P=0.001), deep scar (P=0.001) and dural adhesion (P=0.01) except new bone formation. The presence of arachnoiditis was less in treatment group (P=0.01). CONCLUSION: In rats, the topical thrombolysis with rt-PA is safe and efficacious in preventing postlaminectomy epidural fibrosis. This Thrombolytic therapy with rt-PA after spine surgery may come to play an important role in the prevention of epidural fibrosis and arachnoiditis.

Animals↗

PubMed2002

Protective effect of posterior cerebral circulation on carotid body ischemia.

BACKGROUND AND PURPOSE: Carotid Bodies (CB) are fed mainly by External Carotid Artery (ECA) and rarely by Internal Carotid Artery (ICA). We aimed to investigate the effect of Bilateral Common Carotid Artery ligation and BCCAL plus bilateral external carotid artery ligation on CB. METHODS: This study has been conducted on 30 hybrid male rabbits. Normal CB analyses were made in six of these animals and others divided into two groups. BCCAL has been applied to the 1st group, and the 2nd group has undergone bilateral ECA ligation in addition to BCCAL. After sacrificing the animals, both sides CB were histopathologically observed. Normal and ischemic cells were counted. FINDINGS: Bilateral Common Carotid Artery ligation did not cause total atrophy in CB. Partial reversible atrophy of CB was seen in group I, but that atrophy was found to be irreversible and all animals died within one week after ligation in group II. INTERPRETATION: Retrograde blood flow mechanisms and collateral circulation impede the oligemic CB atrophy after BCCAL. But bilateral ECA ligation, in addition to BCCAL, causes both sides irreversible CB atrophy and death of animals within one week of ligation. ABSTRACT: The CB are parasympathetic paraganglia. They are chemoreceptors and located at the bifurcation zone of common carotid arteries. They are fed mainly by ECA or by its branches and rarely by ICA. As a consequence of this, BCCAL and/or ligation of external branches of common carotid artery may lead to an ischemic impairment of CB. In order to analyse the effect of carotid stenosis on CB, CB were directly examined in 6 of 30 hybrid rabbits. BCCAL was applied to twelve rabbits (group I) with ligation of both ECA in addition to BCCAL were made to the others (group II). Animals were followed up four months in group I; but all of the animals in group II died within one week. From both sides the CB were taken including the carotid bifurcation and histopathological changes were evaluated. As a result, it has been observed that incomplete ischemic lesions have developed in the CB because of retrograde blood flow from posterior circulation to the ECA providing blood for the CB. But in the second group these changes were irreversible and on both sides CB complete atrophy developed in those whose ECA were also ligated bilaterally.

Animals↗

PubMed2002

Widespread post-traumatic acute spinal subdural haematoma: case report and review of the literature.

STUDY DESIGN: A case report of acute post-traumatic spinal subdural haematoma (ASSH). OBJECTIVE: To report a rare post-traumatic problem. SETTING: Dicle University Hospital, Diyarbakir, Turkey. METHOD: A 3-year-old boy was admitted to our clinic with paraplegia 24 h after falling from a height of about 5 meters. Investigation revealed an acute spinal subdural haematoma. RESULTS: Following surgery there was marked improvement. The rehabilitation of the patient continues. CONCLUSION: MRI is the most valuable diagnostic method. In each case diagnosed as ASSH, prompt evacuation should be performed before irreversible neurological damage occurs.

Acute Disease↗

PubMed2001

Growth rate of cerebral hydatid cyst, with a review of the literature.

This extremely rare case was one of secondary solitary cerebral echinococcosis associated with possible cerebral thromboembolism. A 7-year-old girl living in a rural area was admitted to our hospital with a history of headache, right-sided hemiparesis, and dysphasia. She had been treated 6 months previously for a cerebral infarct, diagnosed from sudden altered consciousness and a myoclonic generalised convulsion. The growth rate determined for the cerebral hydatid cyst was about 4.5 cm during the 6-month period. In children a parasitic cyst can be the source of a cerebral embolus, particularly in areas where hydatid disease resulting from cardiac echinococcosis is endemic.

Brain Diseases↗

PubMed2001

Gigantic intracranial mass of hydatid cyst.

A child (8 years old) with a gigantic mass of intracranial hydatid cysts (95x90x75 mm) is presented. The first manifestation was difficulty in walking, which was followed by symptoms of raised intracranial pressure. A craniotomy was performed, and more than 25 hydatid cysts were removed. The literature is reviewed and the incidence of gigantic mass of cerebral hydatid cyst is compared in the published reports.

Brain↗

PubMed2001

Synovial cyst at the intervertebral foramina causing lumbar radiculopathy.

OBJECTIVE: To determine the presence of intraforaminal synovial cysts resulting in nerve root compression. METHODS: A 26 year old man presenting with left leg pain was admitted. He had no motor, sensory, or reflex changes. Magnetic resonance imaging (MRI) and MRI-myelography showed an intra and extra foraminal, extradural, cystic lesion at L4 vertebra on the left side. RESULTS: At surgery there was a cystic mass pressing on the nerve root, and no connection or communication with the dural structures could be found. CONCLUSION: Synovial cysts are uncommon extradural degenerative lesions. Intraspinal synovial cysts occur most often at the L4-5 level, but they have been reported in all areas of the spine except the intraforaminal region and the sacrum.

Adult↗

PubMed2000

Corrosive injuries of the esophagus in newborns.

To evaluate the morbidity and mortality of corrosive esophageal injuries (CEI) in the neonatal period, the records of 184 children hospitalized following caustic ingestion over a 10-year period from January 1987 to November 1997 were reviewed. Eight (4.3%) were newborns (5 boys and 3 girls). The mean age of the newborns was 12 days (range 1-28). The ingested caustic materials were benzalkonium chloride in six patients and trichloroacetic acid in two. Oropharyngeal examination and esophagoscopy were performed for diagnosis. Hyperemia and fibrin plaques were present in the oropharynx in all patients. The management consisted of endotracheal intubation, antibiotics, corticosteroids, and total parenteral nutrition. Pneumonia and sepsis developed in three patients and one died of sepsis. Stenosis developed in two patients, who were treated three times with antegrade dilatations. The morbidity was 62.5% (five patients) and the mortality was 12.5% (one) in newborns with CEI. These results indicate that ingestion of a caustic substance results in high morbidity and mortality in newborns. Parents and nurses should be warned about this risk.

Benzalkonium Compounds↗

PubMed2000

CT of the brain in tuberculous meningitis. A review of 289 patients.

PURPOSE: In this retrospective study, CT findings of 289 patients with tuberculous meningitis (TBM) are presented and diagnostic criteria are discussed. MATERIAL AND METHODS: The medical records of patients who were diagnosed as having central nervous system tuberculosis were investigated. Cranial CT investigations of 289 patients with TBM were reviewed. Of these 289 patients, 214 were children and 75 adults; 157 patients were male and 132 were female. CT images were obtained with and without i.v. contrast administration. RESULTS: CT findings were normal in 35 patients and abnormal in 254. The abnormalities were hydrocephalus (172 children, 32 adults), parenchymal enhancement (56 children, 6 adults), contrast enhancement of basal cisterns (32 children, 17 adults), cerebral infarct and focal or diffuse brain edema (29 children, 10 adults), and tuberculoma (9 children, 5 adults). CONCLUSION: CT is pathologic in the great majority of patients with TBM and is helpful in assessing the complications associated with the disease.

Adolescent↗

PubMed2000

Spinal subdural tuberculous abscess.

OBJECTIVES: Spinal subdural abscess is rare and only 48 cases have been described to date. In this report, we present an additional spinal subdural tuberculous abscess. METHOD: Tuberculous meningitis was diagnosed with clinical and laboratory findings in a 45-year-old man. A spinal subdural abscess was demonstrated using MRI. Presence of the abscess was revealed by surgical intervention. The diagnosis was confirmed by pathological examination. RESULTS: The patient had been treated for tuberculous meningitis 2 years previously. The disease recurred when anti-tuberculous therapy was prematurely discontinued. During the second treatment, the patient also underwent a ventriculo-peritoneal shunt operation for hydrocephalus. Dizziness and weakness of both legs developed after the postoperative period. Spinal MRI showed a spinal subdural abscess as a iso-intense mass with spinal cord in the T1 and T2 weighted images, ring like enhancement and compression on the spinal cord at T3-T4 level. The patient underwent surgery and the abscess was drained. CONCLUSION: Tuberculosis may cause a spinal subdural abscess and although it is a rare disorder, when encountered MRI is very useful in the diagnosis.

Abscess↗

PubMed1999

Lumbar epidural brucellar abscess causing nerve root compression.

OBJECTIVES: To evaluate the usefulness of MR sequences for the differential diagnosis of spinal brucellar abscesses which mimic lumbar disc herniation. METHODS: We analyzed six patients with brucellar abscesses who had symptoms mimicking lumbar disc herniation. The study group consisted of three women and three men who were 15-67 (mean = 37) years old. Patients were imaged in the axial and sagittal planes with a I.0-T MR scanner using a spine coil. RESULTS: The level of abscesses were accurate in 100% (six of six) of patients with MR imaging. MRI examinations revealed an extradural soft tissue mass which were iso- to hypointense compared to spinal cord on T1WI and hyperintense on T2-weighted images. By contrast study, diffuse homogeneous or slightly heterogeneous enhancements were seen. CONCLUSION: Lumbar extradural brucellar abscess can have lumbar disc disease symptoms. MRI may non-invasively and rapidly reveal the presence of spinal abscess and degree of extension to the spinal canal. Extradural brucellar abscess should be included in the differential diagnosis of radicular symptoms caused by disc herniation.

Abscess↗

PubMed1997

Comparison of microsuturing to the use of tissue adhesives in anastomosing sciatic nerve cuts in rats.

The purpose of this study was to investigate and to compare the effects of microsuturing to that of tissue adhesives (Tisseel) on the healing of anastomosing peripheral nerve incisions. Forty-five Wistar-Albino rats were placed in special cages and separated into three groups (n = 15). In the control group, biliteral sciatic nerves were explored but no incision was made. In the first experimental group, bilateral sciatic nerves were incised and end-to-end anastomosing was performed by microsuturing the epineurium. In the second experimental group, tissue adhesive (Tisseel) was used alone in anastomosing the sciatic nerve cuts. Assessments of the healing processes were demonstrated by 1.electromyography (EMG), 2. measuring the electrical responses of the anastomosed nerves after electrical stimuli, 3. histopathological examination. Statistical analysis of the EMG findings showed that the Tisseel group was the closest in the healing process to the control group. After applying electrical stimuli to the dissected nerves, the resistance value of the Tisseel group was nearest to those of the control group. The histopathological examinations showed highly degenerative nerve bundles and prominent foreign body granuloma at the anastomosed sites of the microsutured group. The granulomatous inflammation was observed to be much less in the Tisseel group. We conclude that the healing effect of Tisseel was found to be superior to that of microsuturing as demonstrated by the findings of EMG, electrical responses of the anastomosed nerves, and histopathological examination.

Anastomosis, Surgical↗

PubMed1997

Complications of 1303 central venous cannulations.

Central venous catheterization (CVC), now a common procedure, has several major complications. We assessed their incidence in a prospective study of 1303 cannulations done in the intensive care unit or operating theatre. Chest radiographs were obtained to verify proper catheter placement and to detect pneumothorax. Complications were arterial puncture in 68 (5.2%) patients, arrhythmias in 21 (1.6%), cardiopulmonary arrest in 1 (0.1%), and pneumothorax in 5 (0.5%). The tip of the CVC was incorrectly located in 149 (11.2%). The chest radiograph was a valuable method for detecting complications of central venous catheterization.

Arrhythmias, Cardiac↗

PubMed1996

Treatment of subdural empyema by burr hole.

Subdural empyema, a collection of pus in the space between the dura and arachnoid, is a rare type of intracranial infection. We report on 23 patients, aged 8 months to 70 years, with subdural empyema who were treated in our clinic between 1989 and 1994. The sources of subdural empyemas were meningitis in five patients, middle ear in five, trauma in four, paranasal sinus in three, complications of surgery and subdural tap in four, and unknown in two patients. The common presentations were headache, focal neurologic deficit, fever, vomiting, seizures, and neck stiffness. Diagnosis was achieved by computerized tomography and neurologic examinations in all cases. Treatment was effected by burr hole or small craniotomy with catheter drainage, and antibiotics were administered to all patients. The mortality rate was 8.7%; the remaining patients made a good recovery without sequelae. We therefore recommend burr hole with catheter drainage plus antibiotics as a method of treating subdural empyema.

Adolescent↗

PubMed1995

Parafalxial empyemas (two cases).

Intracranial infections can locate at anywhere in the brain. Subdural empyemas are the less common type of intracranial infections, and parafalxial localization is seen rare. Findings of intracranial pressure increase developed in a cases who were treated for purulent meningitis. Parafalxial empyemas were diagnosed in succeeding cranial computed tomography. Middle line was drained by means of craniotomy or burrhole. We reported two cases who recovered without any postoperative sequel considered the rare localization site of infection.

Adolescent↗

PubMed1975

Experimental Shwartzman phenomenon in the heart muscle.

Intravenous injection of E. coli culture caused a sudden death in rabbits which were injected Streptococcus culture into the myocardium 24 h before the experiment. Pretreatment of animals with Trasylol-R, before injection of E. coli culture, caused an increase of survival time. In isolated Langendorff perfused heart from myocardially Streptococcus culture injected animals, E. coli culture filtrate caused a transitory increase and then a continuous decrease in coronary perfusion pressure together with an increase in heart rate. These findings are shown to be prevented by previous addition of Trasylol to the perfusion medium. According to these results it is speculated that a Shwartzman-like phenomenon can also occur in the heart muscle. The possible role of the activation of tissue kallikrein system in the production of this phenomenon is discussed.

Animals↗