Lung Transplantation From Donors After Previous Cardiac Surgery: Ideal Graft in Marginal Donor?

Lung transplantation is a limited by donor pool shortage. Despite the efforts to extend the graft acceptability with recurrent donor criteria reformulations, previous cardiothoracic surgery is still considered a contraindication. A donor who underwent cardiac surgery could potentially provide an ideal lung but high intraoperative risks and intrinsic technical challenges are expected during the graft harvesting. The purpose of this study is to present our dedicated protocol and four clinical cases of successful lung procurements from donors who had a previous major cardiac surgery. One donor had ascending aortic root (AAR) substitution, another had mitral valve substitution, and two had coronary artery bypass surgery. The others' eligibility criteria for organ allocation, such as ABO compatibility, PaO₂/FiO₂ ratio, absence of aspiration, or sepsis were respected. In one of the cases with previous coronary bypass grafting, the donor had a veno-arterial extracorporeal membrane oxygenation support. Consequently, the grafts required an ex vivo lung perfusion evaluation. We report the technical details of procurement and postoperative courses of recipients. All procurements were uneventful, without lung damage or waste of abdominal organs related to catastrophic intraoperative events. All recipients had a successful clinical outcome. We believe that successful transplantation is achievable even in a complicated setting, such as cases involving donors with previous cardiac surgery frequently are. Facing lung donor shortage, we strongly support any effort to avoid the loss of possible acceptable lungs. In particular, previous major cardiac surgery does not strictly imply a poor quality of lungs as well as unsustainable graft procurement.

Imaging of post-surgical treatment and of related complications in spinal trauma

Spinal trauma is a devastating event with a high morbidity and mortality. The rationale of imaging is to diagnose the traumatic abnormalities and characterize the type of injury, to estimate the severity of the lesions, to evaluate the potential spinal instability. In case of spinal instability, the goals of operative treatment are decompression of the spinal cord canal and stabilization of the disrupted vertebral column. Particularly, diagnostic imaging, mainly by CT and MR, has a main role in the post-treatment evaluation. The neuroradiological evaluation of the postoperative spine requires a general knowledge of the surgical approach to each spinal region and of the normal temporal evolution of expected postoperative changes. The neuroradiologist should evaluate the devices implanted, their related complications and promptly alert the surgeon of acute complications, mainly vascular and infective. During the follow-up, it is mandatory to know and search chronic complications as pseudomeningocele, accelerated degenerative disease, arachnoiditis, peridural fibrosis. Knowledge of specific complications relating to each surgical approach will assist the neuroradiologist in interpretation of postoperative images.

Tuber Cinereum Hamartomas and Gelastic Epilepsy

We studied five patients with gelastic epilepsy sustained by hamartoma of the tuber cinereum, submitted to EEG and Video-EEG study and to MR examination. The mechanism of ictal laughter, clinical associations and prognosis for seizure control are discussed.

Hamartomas should be always suspected when gelastic seizures occur, and appropriate diagnostic tools should be employed for their diagnosis. In patients presenting with gelastic epilepsy, MR assessment of the hypothalamic region is necessary to identify a hamartoma of the tuber cinereum.

Moreover, the resolution of MR imaging provides a basis to correlate some of the clinical manifestations with the anatomical disposition of the lesion within the hypothalamus.

Gelastic epilepsy seems to correlate with large broad-based hamartomas in relationship with the mamillary bodies. In these cases, surgical treatment should be considered when symptoms are not sufficiently responsive to medical therapy.

Degenerazione dell'unità disco-somatica lombare

Gli autori, attraverso una revisione della letteratura ed uno studio retrospettivo su 125 esami RM, descrivono le alterazioni degenerative del rachide lombare in pazienti anziani, focalizzan-do l'attenzione sulla ricca semeiologia RM della patologia del complesso disco-somatico. Scopo del lavoro e quello di poter discernere le alterazioni a carattere francamente patologico da quelle che possono essere considerate segni del fisiologico invecchiamento rachideo. Viene in particolare evidenziato come la fissurazione radiale dell'anulus sia risultata, in base alla sua presenza significativamente più frequente nel gruppo dei pazienti sintomatici, il miglior segno predittivo di patologia estrusiva discale tra quelli esaminati.

Cervico-Oculo-Acoustic Syndrome in a Male with Consanguineous Parents

Background:

The cervico-oculo-acoustic syndrome comprises Klippel-Feil anomaly, sensorineural deafness and Duane's retraction syndrome. Polygenic, autosomal dominant, and X-linked inheritance have been hypothesized. The disorder has rarely been reported in males.

Case Report:

A 42-year-old male, born of consanguineous parents, presented with Duane's syndrome, mixed hearing loss, C2-C3 fusion, neck stiffness, and right facial palsy. A variety of cardiac, neurological and urogenital anomalies occurred in his relatives. The electro-oculographic studies showed impaired abduction and adduction of the right eye and impaired abduction of the left eye. Vergence, vertical eye movements and peripheral vestibular responses were normal. Somatosensory evoked potentials showed absence of the N13 peak and brainstem auditory evoked potentials bilateral delay of the I-III interpeak latencies.

Conclusions:

Consanguinity of the patient's parents, not previously reported, suggests autosomal recessive inheritance, but autosomal dominant inheritance is indicated by the family history. The pattern of the oculomotor deficit is consistent with bilateral dysplasia of the abducens nuclei with preserved internuclear neurons in the right abducens nucleus. Neurophysiological investigations revealed lower brainstem and cervical cord involvement.

Spontaneous regression of syringomyelia in a young patient with Chiari type I malformation

Syringomyelia is a disorder in which a cyst or cavity forms within the spinal cord. This cyst, called syrinx, can expand and elongate over time, destroying the spinal cord. We describe the case of a young patient with partial spontaneous regression of syringomyelia in Chiari I malformation, confirmed by magnetic resonance imaging three years after the diagnosis. During this period the patient did not experience any clinical symptoms. Although described in literature, spontaneous regression is an unusual event and very few cases have been reported. This case report supports the belief that conservative management together with both clinical and imaging periodic controls should be preferred in stable mild-symptomatic patients.

Magnetic resonance imaging in brachial plexus injury

Brachial plexus injury represents the most severe nerve injury of the extremities. While obstetric brachial plexus injury has showed a reduction in the number of cases due to the improvements in obstetric care, brachial plexus injury in the adult is an increasingly common clinical problem. The therapeutic measures depend on the pathologic condition and the location of the injury: Preganglionic avulsions are usually not amenable to surgical repair; function of some denervated muscles can be restored with nerve transfers from intercostals or accessory nerves and contralateral C7 transfer. Postganglionic avulsions are repaired with excision of the damaged segment and nerve autograft between nerve ends or followed up conservatively. Magnetic resonance imaging is the modality of choice for depicting the anatomy and pathology of the brachial plexus: It demonstrates the location of the nerve damage (crucial for optimal treatment planning), depicts the nerve continuity (with or without neuroma formation), or may show a completely disrupted/avulsed nerve, thereby aiding in nerve-injury grading for preoperative planning. Computed tomography myelography has the advantage of a higher spatial resolution in demonstration of nerve roots compared with MR myelography; however, it is invasive and shows some difficulties in the depiction of some pseudomeningoceles with little or no communication with the dural sac.

Endovascular treatment of cerebral aneurysms using the hydrocoil embolic system

HydroCoils are platinum helical coils coated with a layer of hydrophilic acrylic polymer (hydrogel), which on contact with blood causes disentanglement of polymer chains and expansion. We retrospectively reviewed a series of 29 patients harboring 29 cerebral aneurysms treated with the Hydrocoil Embolic System in the period 2004-2005, discussing the results of endovascular procedures in terms of safety and efficacy. The immediate post-procedure angiographic control demonstrated complete aneurysm occlusion in 21 cases (72.4%), near-complete occlusion in seven cases (24.1%), whereas in one case (3.4%) there was a procedure failure with major perfusion of the sac. Five patients (17.2%) experienced thromboembolic complications, including an asymptomatic lacunar stroke of the head of the caudate nucleus, a thalamic infarct following hypotension secondary to pulmonary edema, temporal ischemia secondary to vasospasm and a small right occipital ischemic lesion. Only one patient (3.4%) suffered a major ischemic accident. No other procedure-related complication occurred. Three-month follow-up control with MR angiography and 12-month follow-up angiography demonstrated no recurrence of aneurysms. Overall, after a mean follow-up of 12 months, the clinical outcome was good recovery in 26 patients (89.6%), moderate disability in three patients (10.3%) and no vegetative status or death. Our HydroCoil series supports the safety and midterm durability of hydrogel-coated aneurysm coils in the treatment of cerebral aneurysms.

Endovascular treatment of a small aneurysm of the superior cerebellar artery with a flow-diverter device. A case report

We describe the case of a 62-year-old woman who presented with a small fusiform left superior cerebellar artery (SCA) aneurysm. Aneurysms located on the SCA are uncommon and their presentation, natural history and clinical management are poorly understood. Reports on the endovascular or surgical management of SCA aneurysms are rare and usually incorporated in clinical series of basilar artery or posterior circulation aneurysms. The patient was treated by delivery of a flow-diverter Pipeline Embolization Device (PED - Chestnut Medical/ev3) at the origin of vessel. She had no procedural complications and the aneurysm volume was reduced. This paper presents additional evidence to literature reports suggesting that the new endovascular flow-diverter devices are an effective and well-tolerated treatment for complex aneurysms. Our review contributes data on the incidence of recurrence as a measure of long-term efficacy of this therapeutic approach.

Spontaneous resolution of Chiari type 1 malformation. A case report and literature review

We describe a 62-year-old woman who presented with a history of ataxia, dizziness and urinary urgency. Neurological examination disclosed a positive Romberg sign, ataxia and postural instability. A magnetic resonance imaging (MRI) scan showed Chiari type 1 malformation (CM1). Forty-eight months later, the patient was clinically improved and underwent a second MRI examination, which showed complete resolution of the Chiari 1 malformation. Spontaneous resolution of CM1 is exceptionally rare and has to be considered in the radiological and clinical management.

Endovascular treatment of vertebro-vertebral arteriovenous fistula. A report of three cases and literature review

This report describes endovascular approaches for occlusion of vertebro-vertebral arteriovenous fistula (VV-AVF) in a series of three cases and a review of the literature. Complete neuroimaging assessment, including CT, MR and DSA was performed in three patients (two female, one male) with VV-AVF. Based on DSA findings, the VV-AVF were occluded by endovascular positioning of detachable balloons (case 1), coils (case 2), or a combination of both (case 3) with parent artery patency in two out of three cases. In this small series, endovascular techniques for occlusion of VV-AVF were safe and effective methods of treatment. To date, there are no guidelines on the best treatment for VV-AVF. Detachable balloons, endovascular coiling, combined embolization procedures could all be considered well-tolerated treatments.

Epidemiology and genetics of intracranial aneurysms

Intracranial aneurysms are acquired lesions (5-10% of the population), a fraction of which rupture leading to subarachnoid hemorrhage with devastating consequences. Until now, the exact etiology of intracranial aneurysms formation remains unclear. The low incidence of subarachnoid hemorrhage in comparison with the prevalence of unruptured IAs suggests that the vast majority of intracranial aneurysms do not rupture and that identifying those at highest risk is important in defining the optimal management. The most important factors predicting rupture are aneurysm size and site. In addition to ambiental factors (smoking, excessive alcohol consumption and hypertension), epidemiological studies have demonstrated a familiar influence contributing to the pathogenesis of intracranial aneurysms, with increased frequency in first- and second-degree relatives of people with subarachnoid hemorrhage. In comparison to sporadic aneurysms, familial aneurysms tend to be larger, more often located at the middle cerebral artery, and more likely to be multiple. Other than familiar occurrence, there are several heritable conditions associated with intracranial aneurysm formation, including autosomal dominant polycystic kidney disease, neurofibromatosis type I, Marfan syndrome, multiple endocrine neoplasia type I, pseudoxanthoma elasticum, hereditary hemorrhagic telangiectasia, and Ehlers-Danlos syndrome type II and IV. The familial occurrence and the association with heritable conditions indicate that genetic factors may play a role in the development of intracranial aneurysms. Genome-wide linkage studies in families and sib pairs with intracranial aneurysms have identified several loci on chromosomes showing suggestive evidence of linkage, particularly on chromosomes 1p34.3-p36.13, 7q11, 19q13.3, and Xp22. For the loci on 1p34.3-p36.13 and 7q11, a moderate positive association with positional candidate genes has been demonstrated (perlecan gene, elastin gene, collagen type 1 A2 gene). Moreover, 3 of the polymorphisms analyzed in 2 genes (endothelial nitric oxide synthase T786C, interleukin-6 G572C, and interleukin-6 G174C) were found to be significantly associated with ruptured/unruptured aneurysms: the endothelial nitric oxide synthase gene single-nucleotide polymorphisms increased the risk, while IL-6 G174C seemed protective. More recently, two genomic loci (endothelin receptor A and cyclin-dependent kinase inhibitor 2BAS) have been found to be significantly associated with intracranial aneurysms in the Japanese population; endothelin-1 is a potent vasoconstrictor produced by the endothelial cells. Until now, there are no diagnostic tests for specific genetic risk factors to identify patients who are at a high risk of developing intracranial aneurysms. Knowledge of the genetic determinants may be useful in order to allow clues on stopping aneurysm formation and obtain diagnostic tools for identifying individuals at increased risk. Further multicenter studies have to be carried out.

A rare case of intraosseous lipoma involving the sphenoclival region

We describe the case of a 23-year-old man whose CT scan revealed a hypodense lesion reshaping the superior and middle third of the clivus and partially invading the sphenoidal sinus. MRI showed an irregular-shaped lesion occupying the body of the sphenoid bone, involving the superior and middle third of the clivus and sprouting into the sphenoid sinus. The lesion was hyperintense on T1- and T2-weighted sequences with a thin peripheral rim of hypointensity, without enhancement after i.v. gadolinium injection. The pathology report confirmed an intraosseus lipoma. Intraosseous lipomas involving the spheno-clival region are extremely rare. CT and MRI scan interpretation can be troublesome but this rare pathology has to be considered in the differential diagnosis.

Basilar artery hypoplasia

A rare case of segmental hypoplasia of the basilar artery is described in a 49-year-old man with transient vertebrobasilar ischemia, explored by magnetic resonance imaging (MRI) and digital angiography (DA). The embryology, clinical relevance and magnetic resonance findings of this arterial anomaly are discussed, with a review of six previously reported cases. Segmental aplasia was suggested in our case by magnetic resonance, and subsequently confirmed not only by time-of-flight magnetic resonance, but also by DA. Only ultrathin-slice T2-weighted images revealed the real finding of basilar artery hypoplasia. This sequence, not employed in previously reported cases, is mandatory to allow a clear differential diagnosis between basilar artery aplasia and hypoplasia.

Endovascular treatment of a giant dissecting aneurysm of the posterior cerebral artery. A case report and literature review

We describe the case of a 60-year-old man who presented with a giant dissecting aneurysm of the left P2 segment. Intracranial dissecting aneurysms often occur in the vertebrobasilar system, but rarely involve the posterior cerebral artery (PCA). PCA aneurysms tend to have some peculiar features and therefore may be considered a separate entity, even from the vertebrobasilar aneurysms. The patient was treated by endovascular occlusion of both parent vessel and the aneurysm, and he tolerated the procedure well with a complete resolution of clinical deficit, following volume reduction of the aneurysm. This paper presents additional evidence to literature reports suggesting that endovascular parent artery occlusion with coils is an effective and well-tolerated treatment for distal PCA aneurysms. Our review contributes to collect data regarding the incidence of recurrence as a measure of long-term efficacy of this therapeutic approach.

MRI Features of Spinal Solitary Fibrous Tumors

Spinal solitary fibrous tumors (SFT) are very rare neoplasms occurring in the spinal canal, with only 38 cases reported in ten years since the first description. We describe two cases of SFT of the spine and review 33 well-documented cases in the literature to define distinctive radiological and surgical features raising the suspicion of a spinal SFT before histological verification. A 67-year-old man with cervical myeloradiculopathy had a large extramedullary tumor of the cervical spinal canal extending from C4 to C7. On MRI the tumor was isointense on T1-sequences and hypointense on T2-sequences, and had marked contrast enhancement. At surgery, the tumor was intradural extramedullary, with no dural or root attachment, but it was adherent to the cord. Complete tumor removal was achieved with good outcome. A 75-year-old man with progressive thoracic myelopathy had an intramedullary tumor at C6 and C7 level, which was hypointense on T1- and T2-weighted images of MRI. At surgery, the tumor was intramedullary and strongly adherent to the cord; it was successfully removed. Both tumors were composed of elongated cells with a collagen-matrix background. Immunohistochemical staining was positive for vimentin, CD34, and bcl-2, and negative for EMA and S-100 protein. A careful analysis of our own and the other reported cases of spinal SFTs may disclose some peculiar features of this rare tumor. A spinal intramedullary or extramedullary tumor, hypointense on T2-weighted images of MRI, which intraoperatively shows hard consistency, scarce vascularization, no nerve root involvement, no or weak dural attachment, absence of arachnoidal interface, and adherence to the spinal cord may suggest the diagnosis of SFT.

Anatomical variant of origin of ophthalmic artery: case report

We report on one case of variant origin of right ophthalmic artery (OA) from C4 choroidal segment of the right supraclinoid internal carotid artery. A 41-year-old woman affected by bitemporal hemianopsia performed Magnetic Resonance Imaging with gadolinium showing tuberculum sellae meningioma. During angiography we observed this variant of origin of OA. At surgical dissection, we observed this variant in carotid cistern.

DWI Reversibility after Intra-Arterial Thrombolysis. A Case Report and Literature Review

We report our case and review the literature on reversal DWI lesions, ADC thresholds and correlation between DWI lesion and outcome measured with clinical scales. A 30-years old woman was admitted to our hospital 18 hours after stroke onset. Considering the absence of alterations on CT and the worsening of symptomatology, the patient underwent MRI, which showed a slightly hyperintense signal in FLAIR images in the left portion of the pons and midbrain and a more evident bilateral DWI hyperintensity of the pons. The patient was treated with mechanical and pharmacological intra-arterial thrombolysis. The patient showed a rapid improvement of symptoms. Two weeks after the treatment her clinical conditions were characterized by a residual right hemiparesis and complete recovery of right motility, respiratory and swallowing difficulties. MR examination demonstrated a slight signal alteration of the pons left hemiportion and a disappearance of the mesencephalic signal alteration and of the right portion of the pons. DWI lesions represent irreversibly damaged tissue but new evidence suggests that DWI lesions may be reversible, especially with reperfusion, by now well demonstrated in animal models. Therefore acute DWI lesions probably contain not only irreversibly injured tissue but also parts of the penumbra. The debate on the capability of ADC maps to discriminate irreversibly from reversibly damaged tissue is a matter of controversy. ADC values in human stoke are not an independent indicator of tissue viability. The use of thresholds may improve reproducibility but not validity.

Fusiform aneurysm of the proximal anterior cerebral artery (A1)

OBJECTIVE

Fusiform aneurysms of the A1 segment of the anterior cerebral artery (ACA) are exceptional, with only 15 reported cases. This article presents an additional case treated by microsurgical trapping. The aim is to discuss the treatment of these aneurysms based on the aneurysm morphology and the anatomy of the ACA complex.

CASE REPORT

A 52-year-old woman with subarachnoid hemorrhage (Hunt-Hess grade II) showed an aneurysm of the proximal part of the A1 segment of the left ACA involving the whole circumference of the arterial wall on computerized tomography angiography and digital angiography. There was good collateral blood flow from the right ACA to the distal left ACA. A left pterional craniotomy allowed us to expose a large aneurysm of the proximal part of the A1 segment; the artery entered into the aneurysm sac and could not be identified at the level of the aneurysm. Trapping of the aneurysm was performed with a distal clip placed just before the origin of the artery of Heubner. No neurological deficits were observed postoperatively.

CONCLUSION

Clipping of fusiform aneurysms of the A1 segment using an encircling clip is the treatment of choice but, more often, this is impossible. Trapping of the aneurysm with preservation of the perforating branches (mainly the Heubner artery) may be easily performed when collateral blood flow from the contralateral ACA is sufficient.

Covered Stent Implantation for the Treatment of Direct Carotid-Cavernous Fistula and Its Mid-Term Follow-up

SUMMARY

Carotid-cavernous fistulas are abnormal arteriovenous communications either directly between the internal carotid artery and the cavernous sinus or between the dural branches of the internal and external carotid arteries. These fistulas predominantly present with ocular manifestations and they are treated mainly by endovascular techniques in most cases. A detailed review of the literature allowed us to make a complete analysis of the information available on the topic. We describe a case of a direct carotid-cavernous fistula occluded by endovascular implantation of a covered stent, showing the persistence of results after three years.

Sarcoidosis of the thyroid gland associated with hyperthyroidism: review of the literature and report of two peculiar cases

Sarcoidosis is a systemic disease characterized by non-caseating granulomas that rarely involve the thyroid gland. Thyroid sarcoidosis has seldom been documented, and few cases have so far been described in association with hyperthyroidism. Here, we review the literature on this association, report two patients presenting with hyperthyroidism and histologically-proven sarcoidosis, and discuss related clinical, biochemical, pathological and genetic findings.

Preliminary crystallographic analysis of salicylate 1,2-dioxygenase from Pseudaminobacter salicylatoxidans

Salicylate 1,2-dioxygenase, a new ring-fission dioxygenase from the naphthalenesulfonate-degrading strain Pseudaminobacter salicylatoxidans which oxidizes salicylate to 2-oxohepta-3,5-dienedioic acid by a novel ring-fission mechanism, has been crystallized. Diffraction-quality crystals of salicylate 1,2-dioxygenase were obtained using the sitting-drop vapour-diffusion method at 277 K from a solution containing 10%(w/v) ethanol, 6%(w/v) PEG 400, 0.1 M sodium acetate pH 4.6. Crystals belong to the primitive tetragonal space group P4(3)2(1)2 or P4(1)2(1)2, with unit-cell parameters a = 133.3, c = 191.51 A. A complete data set at 100 K extending to a maximum resolution of 2.9 A was collected at a wavelength of 0.8423 A. Molecular replacement using the coordinates of known extradiol dioxygenases structures as a model has so far failed to provide a solution for salicylate 1,2-dioxygenase. Attempts are currently being made to solve the structure of the enzyme by MAD experiments using the anomalous signal of the catalytic Fe(II) ions. The salicylate 1,2-dioxygenase structural model will assist in the elucidation of the catalytic mechanism of this ring-fission dioxygenase from P. salicylatoxidans, which differs markedly from the known gentisate 1,2-dioxygenases or 1-hydroxy-2-naphthoate dioxygenases because of its unique ability to oxidatively cleave salicylate, gentisate and 1-hydroxy-2-naphthoate with high catalytic efficiency.

Stent implantation for treatment of symptomatic spontaneous cervical internal carotid artery dissecting aneurysm. A case report

Cervical internal carotid dissections are rare. Approximately one third of the cases are associated with pseudoaneurysm. The first-choice management of cervical carotid dissecting aneurysms consists in anticoagulation or antiplatelet therapy. Surgery is typically indicated in cases of failure of conservative therapy with recurrent cerebral ischemic attacks. In recent years, stent implantation has been also employed for the management of patients with carotid dissecting aneurysms whose neurological conditions were refractory to medical treatment. In the present case we describe the treatment of a patient with a carotid dissecting aneurysm, by means of endovascular stent application and provide angiographic control 24 months after the intervention.

Bilateral hypoplasia of the internal carotid arteries with basilar aneurysm

We report a rare case of bilateral hypoplasia of the internal carotid arteries with an associated aneurysm of the basilar tip, studied by CT angiography, MR angiography and digital angiography. The patient became symptomatic with an episode of loss of consciousness, likely due to reduced blood perfusion. The other 20 reported cases of bilateral carotid hypoplasia (only four of which with an associated aneurysm) are reviewed. The findings of noninvasive procedures (including narrowing of the carotid canals on CT) may lead to a correct diagnosis before angiography is performed; they may also help to differentiate angiographic narrowing of the hypoplastic internal carotids from the string sign often observed in some acquired conditions.

An unusual case of vertebral arteriovenous fistula treated with electrodetachable coil embolization

Vertebral arteriovenous fistulas (VAF) are rare clinical entities. Most are post-traumatic in origin, following direct injury, or iatrogenic. Treatment options include endovascular occlusion or direct surgical closure. We present a rare case of a spontaneous VAF, presenting with cervical and upper limb pain in a patient with previous chiropractic manipulations, successfully treated with electrodetachable coil embolization. While the natural history of the VAFs is still to be settled, endovascular occlusion appears to be a safe and reliable method to deal with such lesions, mainly in symptomatic cases. The use of electrically detachable coils may be considered as an effective alternative for the endovascular occlusion of these fistulas.

Sudden re-opening of collapsed transverse sinuses and longstanding clinical remission after a single lumbar puncture in a case of idiopathic intracranial hypertension. Pathogenetic implications

The aetiopathogenetic role of sinus venous obstructions carried by most idiopathic intracranial hypertension (IIH) patients is controversial. We report the case of a young woman diagnosed with IIH with papilloedema and narrowing of transverse sinuses, in which lowering of intracranial pressure by a single 20 ml cerebrospinal fluid (CSF) resulted in a strong dimensional increase of the transverse sinuses. Changes were followed by clinical remission and normalisation of optical nerve calibre, maintained after a 2-month follow-up. Our findings indicate that, although secondary to CSF hypertension, venous sinuses compression may have an important role in hypertensive status maintenance. Pathogenetic implications of venous sinus compression by hypertensive CSF in IIH are discussed.

Hemorrhagic Vascular Complications of Endoscopic Transsphenoidal Surgery

Two hundred and fifty consecutive patients operated on by an endoscopic endonasal transsphenoidal approach were retrospectively analyzed in order to evaluate hemorrhagic vascular complications occurring during or after the surgical procedure and their appropriate management. Vascular complications of endoscopic transsphenoidal surgery are identical to those of a microsurgical transsphenoidal approach. Damage to the sphenopalatine artery and to the internal carotid artery (ICA), which are the most frequent vascular troubles, may require technical tricks because of some aspects connected to the approach itself and of the physical properties of the endoscope. Furthermore, the progress in interventional neuroradiology in the last decades offers new solutions in respect to the past, where the use of the surgical microscope was already a tremendous progress. The anatomic substrate of each complication is discussed, along with the peculiar surgical details related to it.

Bilateral chronic subdural hematoma associated with meningioma. Case report and review of the literature

Gross intracranial hemorrhage associated with brain tumor has been reported to range from 3.6-10%. Brain metastases and malignant glioma are the most frequent underlying pathologies. Intracranial hemorrhage related to meningioma is a rare condition. Subarachnoid hemorrhage, acute subdural hematoma, intratumoral and intraparenchymal hematomas are the most common forms of bleeding associated with meningioma. By contrast, chronic subdural hematoma (cSDH) and intraventricular hemorrhage are seen less frequently. The authors report a very rare case of left fronto-parietal convexity meningioma associated with bilateral cSDH in a patient with history of recent minor head trauma and review the literature on hemorrhage associated with meningiomas.

Protease inhibitors: Synthesis of L-alanine hydroxamate sulfonylated derivatives as inhibitors of clostridium histolyticum collagenase

L-alanine hydroxamate derivatives were obtained by reaction of alkyl/arylsulfonyl halides with L-alanine, followed by treatment with benzyl chloride, and conversion of the COOH moiety to the CONHOH group with hydroxylamine in the presence of carbodiimides. Other derivatives were obtained by reaction of N-benzyl-alanine with aryl isocyanates, arylsulfonyl isocyanates or benzoyl isothiocyanate, followed by a similar conversion of the COOH to the CONHOH moiety. The obtained compounds were assayed as inhibitors of Clostridium histolyticum collagenase, ChC (EC 3.4.24.3), a zinc enzyme which degrades triple helical collagen. The hydroxamate derivatives were generally 100-500 times more active than the corresponding carboxylates. In the series of synthesized derivatives, substitution patterns leading to the most potent ChC inhibitors were those involving perfluoroalkylsulfonyl- and substituted-arylsulfonyl moieties, such as pentafluorophenylsulfonyl, 3- and 4-protected-aminophenylsulfonyl-, 3- and 4-carboxy-phenylsulfonyl-, 3-trifluoromethyl-phenylsulfonyl-, or 1- and 2-naphthylsulfonyl among others. Similarly to the matrix metalloproteinase (MMP) hydroxamate inhibitors, ChC inhibitors of the type reported here must incorporate hydrophobic moieties at the P(2') and P(3') sites, in order to achieve tight binding to the enzyme.

Carbonic anhydrase inhibitors. metal complexes of 5-(2-chlorophenyl)-1,3,4-thiadiazole-2-sulfonamide with topical intraocular pressure lowering properties: the influence of metal ions upon the pharmacological activity

Metal complexes of a sulfonamide possessing strong carbonic anhydrase (CA) inhibitory properties, 5-(2-chlorophenyl)-1,3,4-thiadiazole-2-sulfonamide (chlorazolamide) have been obtained from the sodium salt of the sulfonamide and the following metal ions: Mg(II), Zn(II), Mn(II), Cu(II), Co(II), Ni(II), Be(II), Cd(II), Pb(II), Al(III), Fe(III) and La(III). The original sulfonamide and its complexes were assayed for the in vitro inhibition of three CA isozymes, CA I, II, and IV, some of which play a critical role in ocular fluid secretion. All these compounds (the sulfonamide and its metal complexes) behaved as powerful inhibitors against the three investigated isozymes. The parent sulfonamide possessed an extremely weak topical pressure lowering effect when administered as a 1-2% suspension into the rabbit eye, but some of its metal complexes, such as the Mg(II), Zn(II), Mn(II) and Cu(II) derivatives, lower intraocular pressure (IOP) in experimental animals very well. Ex vivo data showed a 99.5-99.9% CA II inhibition in ocular fluids and tissues of rabbits treated with these agents, proving that the observed IOP lowering is due to CA inhibition. The influence of the different metal ions upon the efficiency of the obtained complexes as pressure lowering drugs are discussed, leading to the possibility of designing more selective/potent pharmacological agents from this class.

Development of "de novo" aneurysms following endovascular procedures

Two personal cases of "de novo" aneurysms of the anterior communicating artery (ACoA) occurring 9 and 4 years, respectively, after endovascular carotid occlusion are described. A review of the 30 reported cases (including our own two) of "de novo" aneurysms after occlusion of the major cerebral vessels has shown some features, including a rather long time interval after the endovascular procedure of up to 20-25 years (average 9.6 years), a preferential ACoA (36.3%) and internal carotid artery-posterior communicating artery (ICA-PCoA) (33.3%) location of the "de novo" aneurysms, and a 10% rate of multiple aneurysms. These data are compared with those of the group of reported spontaneous "de novo" aneurysms after SAH or previous aneurysm clipping. We agree that the frequency of "de novo" aneurysms after major-vessel occlusion (two among ten procedures in our series, or 20%) is higher than commonly reported (0 to 11%). For this reason, we suggest that patients who have been submitted to endovascular major-vessel occlusion be followed up for up to 20-25 years after the procedure, using non-invasive imaging studies such as MR angiography and high-resolution CT angiography. On the other hand, periodic digital angiography has a questionable risk-benefit ratio; it may be used when a "de novo" aneurysm is detected or suspected on non-invasive studies. The progressive enlargement of the ACoA after carotid occlusion, as described in our case 1, must be considered a radiological finding of risk for "de novo" aneurysm formation.

Efficient polycyclic aromatic hydrocarbons dihydroxylation in direct micellar systems

Optimization of whole-cell bioconversion of the polycyclic aromatic hydrocarbons (PAHs) anthracene, phenanthrene, and naphthalene to the enantiomerically pure corresponding cis-dihydroxydihydro derivatives by the Escherichia coli JM109 (pPS1778) recombinant strain, carrying the naphthalene dioxygenase and corresponding regulatory genes cloned from Pseudomonas fluorescens N3, in micellar systems, is presented. We show that direct microemulsion systems, where a nonionic surfactant such as 1.5% (v/v) Triton X-100 plus 0.6% to 1.0% (v/v) selected oils are able to solubilize the PAHs tested at relatively high concentrations (initial concentrations in the reaction medium > or =10 mM for naphthalene and phenanthrene and > or =2 mM for anthracene), and allow for more efficient substrate bioconversion. These media, while not affecting bacteria viability and performance, provide increased efficiency and final product yields (100% for naphthalene, >30% for anthracene, >60% for phenanthrene). The phase behavior of the direct microemulsion systems for the different substrates and oils utilized was monitored as a function of their volume fraction by light scattering experiments, and related to the bioconversion results. For anthracene and phenanthrene, the dihydroxylated products have an inhibitory effect on the conversion reactions, thus hindering complete turnover of the substrates. We ascertain that such inhibition is reversible because removal of the products formed allowed the process to start over at rates comparable to initial rates. To allow for complete conversion of the PAHs tested a stepwise or continuous separation of the product formed from the micellar reaction environment is being developed.

Dural arteriovenous malformation associated with recurrent subdural haematoma and intracranial hypertension

An unusual case of intracranial hypertension and symptoms of a left parieto-occipital mass lesion due to a dural arteriovenous malformation (AVM) with a large and dilated draining vein is reported. The patient also had a history of homolateral recurrent subdural haematoma, 11 years before. Subdural haematoma is rarely associated to a dural AVM. We suggest that the recurrent subdural haematoma was due to the very slow and intermittent venous bleeding from the preexisting dural malformation, which progressively enlarged in the following years to become very large. The symptoms of intracranial hypertension and papilloedema may be explained by the increased pressure in the dural sinus and the cerebral venous system. On the other hand, focal neurological symptoms in our case resulted from the mass effect due to an aneurysmally dilated draining vein in the left parieto-occipital region.

Carbonic anhydrase inhibitors: sulfonamides as antitumor agents?

Novel sulfonamide inhibitors of the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1) were prepared by reaction of aromatic or heterocyclic sulfonamides containing amino, imino, or hydrazino moieties with N,N-dialkyldithiocarbamates in the presence of oxidizing agents (sodium hypochlorite or iodine). The N,N-dialkylthiocarbamylsulfenamido-sulfonamides synthesized in this way behaved as strong inhibitors of human CA I and CA II (hCA I and hCA II) and bovine CA IV (bCA IV). For the most active compounds, inhibition constants ranged from 10(-8) to 10(-9) M (for isozymes II and IV). Three of the derivatives belonging to this new class of CA inhibitors were also tested as inhibitors of tumor cell growth in vitro. These sulfonamides showed potent inhibition of growth against several leukemia, non-small cell lung, ovarian, melanoma, colon, CNS, renal, prostate and breast cancer cell lines. With several cell lines. GI50 values of 10-75 nM were observed. The mechanism of antitumor action with the new sulfonamides reported here remains obscure, but may involve inhibition of CA isozymes which predominate in tumor cell membranes (CA IX and CA XII), perhaps causing acidification of the intercellular milieu, or inhibition of intracellular isozymes which provide bicarbonate for the synthesis of nucleotides and other essential cell components (CA II and CA V). Optimization of these derivatives from the SAR point of view, might lead to the development of effective novel types of anticancer agents.

Protease inhibitors: Part 4. Synthesis of weakly basic thrombin inhibitors incorporating pyridinium-sulfanilylaminoguanidine moieties

Three series of derivatives have been prepared by reaction of sulfanilylaminoguanidine with pyrylium salts, with the pyridinium derivatives of glycine and with the pyridinium derivatives of beta-alanine, respectively. The new compounds were assayed as inhibitors of two serine proteases, thrombin and trypsin. The study showed that in contrast to the leads, possessing KI's around 100-300 nM against thrombin, and 450-1420 nM against trypsin, respectively, the new derivatives showed inhibition constants in the range of 15-50 nM against thrombin, whereas their affinity for trypsin remained relatively low. Derivatives of beta-alanine were more active than the corresponding glycine derivatives, which in turn were more inhibitory than the pyridinium derivatives of sulfanilylaminoguanidine possessing the same substitution pattern at the pyridinium ring. Thus, the present study proposes two novel approaches for the preparation of high affinity, specific thrombin inhibitors: a novel S1 anchoring moiety in the already large family of arginine/amidine-based inhibitors, i.e., the SO2NHNHC(=NH)NH2 group, and novel non-peptidomimetic scaffolds obtained by incorporating alkyl-/aryl-substituted-pyridinium moieties in the hydrophobic binding site(s). The first one is important for obtaining bioavailable thrombin inhibitors, devoid of the high basicity of the commonly used arginine/amidine-based inhibitors, whereas the second one may lead to improved water solubility of such compounds.

Carbonic anhydrase inhibitors: synthesis of sulfonamides incorporating 2,4,6-trisubstituted-pyridinium-ethylcarboxamido moieties possessing membrane-impermeability and in vivo selectivity for the membrane-bound (CA IV) versus the cytosolic (CA I and CA II) isozymes

A new approach is proposed for the selective in vivo inhibition of membrane-bound versus cytosolic carbonic anhydrase (CA, EC 4.2.1.1) isozymes with a class of positively-charged, membrane-impermeant sulfonamides. Aromatic/heterocyclic sulfonamides acting as strong (but unselective) inhibitors of this zinc enzyme were derivatized by the attachment of trisubstituted-pyridinium-ethylcarboxy moieties (obtained from 2,4,6-trisubstituted-pyrylium salts and beta-alanine) to the amino, imino, hydrazino or hydroxyl groups present in their molecules. Efficient in vitro inhibition (in the nanomolar range) was observed with some of the new derivatives against three investigated CA isozymes, i.e., hCA I, hCA II (cytosolic forms) and bCA IV (membrane-bound isozyme; h = human; b = bovine isozyme). Due to their salt-like character, the new type of inhibitors reported here, unlike the classical, clinically used compounds (such as acetazolamide, methazolamide, ethoxzolamide), are unable to penetrate biological membranes, as shown by ex vivo and in vivo perfusion experiments in rats. The level of bicarbonate excreted into the urine of the experimental animals perfused with solutions of the new and classical inhibitors suggest that: (i) when using the new type of positively-charged sulfonamides, only the membrane-bound enzyme (CA IV) was inhibited, whereas the cytosolic isozymes (CA I and II) were not affected, (ii) in the experiments in which the classical compounds (acetazolamide, benzolamide, etc.) were used, unselective inhibition of all CA isozymes (I, II and IV) occurred.

Carbonic anhydrase inhibitors: perfluoroalkyl/aryl-substituted derivatives of aromatic/heterocyclic sulfonamides as topical intraocular pressure-lowering agents with prolonged duration of action

Reaction of perfluoroalkyl/arylsulfonyl chlorides or perfluoroalkyl/arylcarbonyl chlorides with aromatic/heterocyclic sulfonamides possessing a free amino/imino/hydrazino/hydroxy group afforded compounds with the general formula C(x)()F(y)()Z-A-SO(2)NH(2), where Z = SO(2)NH, SO(3), CONH, or CO(2) and A = aromatic/heterocyclic moiety. The sulfonyl chlorides used in synthesis included: CF(3)SO(2)Cl, n-C(4)F(9)SO(2)Cl, n-C(8)F(17)SO(2)Cl, and C(6)F(5)SO(2)Cl, whereas the acyl chlorides were C(8)F(17)COCl and C(6)F(5)COCl. A total of 25 different sulfonamides have been derivatized by means of the above-mentioned perfluorosulfonyl/acyl halides. These new series of sulfonamides showed strong affinities toward isozymes I, II, and IV of carbonic anhydrase (CA). For a given sulfonamide derivatized by the above procedures, inhibitory power was greater for the alkyl/arylsulfonylated compounds, as compared to the corresponding perfluoroalkyl/arylcarbonylated ones. In vitro inhibitory activity generally increased with the number of carbon atoms in the molecule of the acylating/sulfonylating agent, with a maximum for the perfluorophenylsulfonylated and perfluorobenzoylated derivatives. Some of the prepared CA inhibitors displayed very good water solubility (in the range of 2%) and strongly lowered intraocular pressure (IOP) when applied topically, directly into the normotensive/glaucomatous rabbit eye, as 2% water solutions. The good water solubility of these new classes of CA inhibitors, correlated with the neutral pH of their solutions used in the ophthalmologic applications, makes them attractive candidates for developing novel types of antiglaucoma drugs devoid of unpleasant ocular side effects.

Purification and catalytic properties of two catechol 1,2-dioxygenase isozymes from benzoate-grown cells of Acinetobacter radioresistens

Two catechol 1,2-dioxygenase (C1,2O) isozymes (IsoA and IsoB) have been purified to homogeneity from a strain of Acinetobacter radioresistens grown on benzoate as the sole carbon and energy source. IsoA and IsoB are both homodimers composed of a single type of subunit with molecular mass of 38,600 and 37,700, Da respectively. In conditions of low ionic strength, IsoA can aggregate as a trimer, in contrast to IsoB, which maintains the dimeric structure, as also supported by the kinetic parameters (Hill numbers). IsoA is identical to the enzyme previously purified from the same bacterium grown on phenol, whereas the IsoB is selectively expressed using benzoate as carbon source. This is the first evidence of the presence of differently expressed C1,2O isozymes in A. radioresistens or more generally of multiple C1,2O isozymes in benzoate-grown Acinetobacter cells. Purified IsoA and IsoB contain approximately 1 iron(III) ion per subunit and both show electronic absorbance and EPR features typical of Fe(III) intradiol dioxygenases. The kinetic properties of the two enzymes such as the specificities toward substituted catechols, the main catalytic parameters, and their behavior in the presence of different kind of inhibitors are, unexpectedly, very similar, in contrast to most of the previously known dioxygenase isozymes.