Strategy for the retreatment of failed Helicobacter pylori eradication therapy: a case series

BACKGROUND

Helicobacter pylori eradication therapy can be unsuccessful in 5 to 20% of patients.

AIM

To investigate the validity of a strategy using triple therapies for the retreatment of patients with eradication failure, avoiding retreatment with antibiotics prone to induce resistance after use in the first treatment.

PATIENTS AND METHODS

From a consecutive sampling of 108 patients still Helicobacter pylori-positive after a first course of antibiotic-based treatment, 74 (68.5%) agreed to a second course of triple therapy. Group 1 (N = 17): treatment failures on an imidazole (1)-based therapy were retreated with clarithromycin (C)-based regimen; Group 2 (N = 28): failures on a C-based therapy with an I-based regimen; Group 3 (N = 7): failures on an IC-based therapy using an I-based regimen and Group 4 (N = 22): failures on a non-I/non-C based therapy with either an I-based, C-based or IC-based regimen. The presence of Helicobacter pylori was assessed by histology and the CLO-test at study entry and two months after stopping therapy.

RESULTS

Nine patients were withdrawn from the study (12.2%) due to a lack of end point endoscopy. Helicobacter pylori was cured after the second course of therapy in all but seven patients [10.7% failure by Per Protocol analysis, 21.6% by Intention-To-Treat analysis]. No statistically significant differences were found between the four groups (Group 1: 92.9% PP, 76.5% ITT; Group 2: 90.9% PP, 71.4% ITT; Group 3: PP and ITT 85.7%; Group 4: PP and ITT 86.4%). Minor adverse events were experienced in nine, none of whom required withdrawal from the drug therapy.

CONCLUSIONS

A second course of triple therapy with alternate antibiotics effectively eradicated Helicobacter pylori, with only very few treatment failures. This suggests that the therapeutic strategy employed may be recommended.

Alterations in 8-hydroxy-2-(dipropylamino)tetralin-induced neuroendocrine responses after 5,7-dihydroxytryptamine-induced denervation of serotonergic neurons

In the present study, we examined denervation-induced changes in the sensitivity of hypothalamic postsynaptic serotonin1A (5-HT1A) receptor function with respect to changes in the dose-dependent elevation in plasma hormones [adrenocorticotropic hormone (ACTH), corticosterone, prolactin, oxytocin, prolactin, renin and vasopressin] by the 5-HT1A agonist 8-hydroxy-2-(dipropylamino)tetralin (8-OH-DPAT). Rats received intracerebroventricular (i.c.v.) injections of the serotonin neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) or vehicle (0.1% ascorbate in saline) 3 weeks before challenge with increasing doses of 8-OH-DPAT (0, 10, 50 or 200 micrograms/kg s.c.). The effectiveness of 5,7-DHT-induced destruction of serotonergic neurons was confirmed by a 93% reduction in [3H]paroxetine-labeled 5-HT uptake sites in the hypothalamus. No changes in basal levels of ACTH, corticosterone, oxytocin, prolactin, renin and vasopressin were observed in rats that received i.c.v. 5,7-DHT injections. The dose-response curves for 8-OH-DPAT-induced elevations of plasma corticosterone and prolactin levels were shifted to the left in rats treated with 5,7-DHT, whereas no significant difference in the ACTH dose-response curve was observed between rats treated with vehicle and rats treated with 5,7-DHT. In contrast, the maximal oxytocin response to 8-OH-DPAT was attenuated in rats treated with 5,7-DHT. A 5,7-DHT-induced decline in the synthesis of oxytocin could explain this phenomenon. Although 8-OH-DPAT did not increase plasma levels of renin or vasopressin in rats treated with vehicle, 8-OH-DPAT produced an elevation (75%) in plasma renin concentration but not in vasopressin levels in rats that received i.c.v. injections of 5,7-DHT. No change was observed in [3H]8-OH-DPAT labeled 5-HT1A receptors in the hypothalamus. In summary, denervation of hypothalamic serotonergic nerve terminals produces supersensitivity of some neuroendocrine responses to 8-OH-DPAT independent of changes in the density of hypothalamic 5-HT1A receptors.

Optimal PPI-based triple therapy for the cure of Helicobacter pylori infection: a single center comparison of four 14-day schedules

BACKGROUND

Helicobacter pylori eradication is accomplished using a wide array of drugs combined in a multitude of dosage schedules. The aim of the present study was to define the best 14-day eradication schedule using a PPI plus either two antibiotics or one antibiotic and bismuth.

MATERIAL AND METHODS

For this study, 367 subjects (198 males, 169 females, age 22-87 years) with document H. pylori infection of the stomach were recruited from out-patients of the Gastroenterology Department of the Venezia Hospital. In all patients, H. pylori infection was identified by histology and the CLO-test. Patients were treated as follows: 1) PPI (P) plus clarithromycin (C) 250 mg plus amoxicillin (A) 1000 mg bid (P + C + A); 2) P plus C plus bismuth subcitrate (B) 120 mg qid (P + C + B); 3) P plus C plus tinidazole (T) 500 mg bid (P + C + T); and 4) P plus A plus T bid (P + A + T). After two months, an upper gastrointestinal endoscopy was repeated for end point histological evaluation and the CLO- test. Positivity of one of the two methods was considered sufficient to define H. pylori as "not eradicated".

STATISTICS

Chi-squared test and Fisher exact test.

RESULTS

Thirty-three subjects dropped out (six due to adverse events). P + C + B was proven significantly less effective than P + C + A, P + C + T and P + A + T, eradication rates being, respectively, 75.0%, 90.5%, 87.6%, 92.0%, (p = .005, per protocol analysis).

CONCLUSIONS

All PPI-based triple therapies tested in this study were effective in curing H. pylori infection; however, P + C + B resulted in rates too low (< 85%) to be recommended. P + C + A and P + A + T resulted in the high cure rates and thus may be considered the treatment of choice.

Dysplastic neocortex and subcortical heterotopias in methylazoxymethanol-treated rats: an intracellular study of identified pyramidal neurones

Intracellular recordings were obtained using biocytin-filled electrodes from 78 neurones located in both dysplastic neocortex and subcortical heterotopic aggregates in a model of neuronal migration disorder induced in rats by means of a double methylazoxymethanol injection given on embryonic day 15. Both regular spiking and intrinsically bursting pyramidal neurones were found in all of the examined structures and were synaptically activated by subcortical stimulation. In a neuronal subpopulation (22%) located in the neocortex as well as in the subcortical heterotopic aggregates, the injection of depolarising current pulses elicited aberrant firing patterns, consisting of repetitive bursts of APs that gradually increased in duration and eventually merged in a long-lasting discharge. The gradual development of this 'excessive' bursting behaviour suggests a progressive run-down of the slow components of the hyperpolarising afterpotential.

WAY-100635 inhibits 8-OH-DPAT-stimulated oxytocin, ACTH and corticosterone, but not prolactin secretion

Previous studies suggest that the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT) increases the secretion of oxytocin, adrenocorticotropic hormone (ACTH), corticosterone and prolactin but not renin. However, the lack of selective 5-HT1A receptor antagonists made it difficult to confirm that 5-HT1A receptors mediate the neuroendocrine responses to 8-OH-DPAT. This study investigated the effects of increasing doses of a selective 5-HT1A receptor antagonist, N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexanecarboxamide (WAY-100635) on neuroendocrine responses induced by the 5-HT1A receptor agonist 8-OH-DPAT in adult male rats. 8-OH-DPAT, 500 microg/kg s.c., increased plasma levels of oxytocin (to 970% above basal levels); ACTH (to 1622% above basal levels), corticosterone (to 458% above basal levels) and prolactin (to 313% above basal levels), but not renin. The lowest dose of WAY-100635 (0.1 mg/kg s.c.) significantly inhibited the 8-OH-DPAT-induced increase in plasma oxytocin but not ACTH or corticosterone levels. At a dose of 1 mg/kg (s.c.), WAY-100635 completely blocked the oxytocin and ACTH responses and maximally inhibited the corticosterone response to 8-OH-DPAT, although corticosterone levels were still above basal. In contrast, the increase in prolactin secretion, induced by 8-OH-DPAT was not inhibited by any dose of WAY-100635. At the highest dose of WAY-100635 (10 mg/kg, s.c.), basal prolactin levels were markedly elevated (1550%) and administration of 8-OH-DPAT significantly elevated plasma renin concentration. Taken together, these data indicate that: (1) 8-OH-DPAT stimulates oxytocin, ACTH, and corticosterone but not prolactin secretion via activation of 5-HT1A receptors and (2) blockade of 5-HT1A receptors may unmask 8-OH-DPAT simulation of renin secretion via non-5-HT1A receptor mechanisms.

Low dose of clarithromycin in triple therapy for the eradication of Helicobacter pylori: one or two weeks?

The aims of this pilot study were: (i) to compare the efficacy of low-dose clarithromycin (250 mg twice daily) for 1 or 2 weeks; and (ii) to evaluate possible therapeutic advantages in associating the low-dose clarithromycin with an anti-secretory agent or tripotassium dicitrate bismuthate (De Nol; Yamanouchi Pharm, Corugate Milano, Italy). A prospective, randomized, open trial was carried out on consecutive outpatients with dyspeptic symptoms and Helicobacter pylori infection. We enrolled 129 patients in one of the following schedules: (A) De Nol 120 mg q.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 2 weeks; (B) omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 2 weeks; or (C) omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 1 week. Results were evaluated by Per Protocol (PP) and Intention-To-Treat analysis (ITT). Eradication rate was 100% after treatment A, 92.6% after treatment B and 86.5% after treatment C by PP and 83.3, 75.7, and 68.1%, respectively by ITT. Side effects were reported by 16 subjects: 26.6% in group A; 9.1% in group B; and 7.5% in group C; in two cases side effects led to the withdrawal of the treatment. In conclusion, 500 mg clarithromycin per day in association with omeprazole and metronidazole, for 1 week gave comparable results to the same schedule for a 2 week period. The use of clarithromycin with bismuth and metronidazole produced a therapeutic gain compared with both of the anti-secretory schedules, although this was not statistically significant.

Cortical dysplasia: an immunocytochemical study of three patients

Human cortical dysplastic lesions are frequently associated with severe partial epilepsies. We report an immunocytochemical investigation on cortical tissue from three surgically treated patients, 20, 38, and 14 years old, with intractable epilepsy due to cortical dysplasia. The studies were performed using antibodies recognizing cytoskeletal proteins, calcium-binding proteins, and some subunits of glutamate receptors. The specimens from the three patients displayed common features: (1) focal cytoarchitectural abnormalities with an increased number of giant pyramidal neurons through all cortical layers except layer I; (2) large, round-shaped balloon cells mainly concentrated in the deepest part of the cortex and in the white matter; (3) a decrease of calcium binding protein immunopositive gamma-aminobutyric acid (GABA)ergic neurons; and (4) abnormal baskets of parvalbumin-positive terminals around the excitatory (pyramidal and large, round-shaped) neurons. These data provide evidence that the epileptogenicity in these types of cortical dysplasia is due to an increase in excitatory neurons coupled with a decrease in GABAergic interneurons.

Portal hypertensive gastropathy: reproducibility of a classification, prevalence of elementary lesions, sensitivity and specificity in the diagnosis of cirrhosis of the liver. A NIEC multicentre study. New Italian Endoscopic Club

OBJECTIVE

To classify elementary endoscopic lesions of portal hypertensive gastropathy, assess their reproducibility, prevalences, sensitivity and specificity in the diagnosis of cirrhosis of the liver.

METHODS

1) A classification of portal hypertensive gastropathy elementary lesions was defined. 2) Thirty-two endoscopists evaluated videotapes of endoscopic examinations of patients with liver cirrhosis to assess beyond-chance agreement (kappa). 3) Fifteen centres enrolled consecutive patients with or without cirrhosis of the liver and recorded portal hypertensive gastropathy pattern according to its location.

RESULTS

1) Four elementary lesions (Mosaic-Like Pattern, Red Point Lesions, Cherry Red Spots, Black-Brown Spots) were identified, and graded. 2) A fair to good beyond-chance agreement was obtained for all 4 lesions. 3) portal hypertensive gastropathy prevalence was higher in patients with cirrhosis of the liver (0.63, sensitivity) than in controls (0.17). Mosaic-like pattern was the most prevalent sign (0.54). Specificity of portal hypertensive gastropathy was 0.83. Portal hypertensive gastropathy was tentatively classified as mild or severe when mosaic-like pattern alone or red marks of any kind were present, respectively; this classification led to a further improvement in reproducibility.

CONCLUSIONS

Our results suggest that a sufficient degree of agreement can be achieved in recording portal hypertensive gastropathy. Therefore, the New Italian Endoscopic Club classification should be used to evaluate the natural history of this condition.

Fluoxetine gradually increases [125I]DOI-labelled 5-HT2A/2C receptors in the hypothalamus without changing the levels of Gq- and G11-proteins

The time course of fluoxetine-induced supersensitivity of hypothalamic 5-HT2A/2C receptors was examined. Daily injections of fluoxetine (7 or 14 days) significantly increased agonist ([125I]DOI)-labeled high-affinity-state 5-HT2A/2C receptors in the hypothalamus, but not frontal cortex. No change was observed in the density of [3H]ketanscrin-labeled 5-HT2A receptors in either brain region. The levels of Gq- and G11- proteins in the hypothalamus and cortex were not altered by fluoxetine. These results suggest that fluoxetine gradually increases the G-protein coupling of 5-HT2A/2C receptors without altering the levels of Gq- or G11-proteins.

Expression of neuronal kinesin heavy chain is developmentally regulated in the central nervous system of the rat

The kinesin family of motor proteins comprises at least two isoforms of conventional kinesin encoded by different genes: ubiquitous kinesin, expressed in all cells and tissues, and neuronal kinesin, expressed exclusively in neuronal cells. In the present study, we have analyzed the expression of the two kinesin isoforms by immunochemistry at different stages of development of the rat CNS. We have found that the level of expression of neuronal kinesin is five to eight times higher in developing than in adult rat brains, whereas that of ubiquitous kinesin is only approximately 2.5 times higher in maturing versus adult brains. Moreover, we have studied the distribution of neuronal kinesin by light microscopic immunocytochemistry in the rat brain at different postnatal ages and have found this protein not only to be more highly expressed in juvenile than in adult rat brains but also to show a different pattern of distribution. In particular, tracts of axonal fibers were clearly stained at early postnatal stages of development but were markedly unlabeled in adult rat brains. Our results indicate that the expression of at least one isoform of conventional neuron-specific kinesin is up-regulated in the developing rat CNS and suggest that this protein might play an important role in microtubule-based transport during the maturation of neuronal cells in vivo.

Periventricular nodular heterotopia: epileptogenic findings

PURPOSE

We studied 17 patients with periventricular nodular heterotopia (PNH) to further investigate the electroclinical pictures and semiology of the associated seizures.

METHODS

PNH was diagnosed by means of magnetic resonance imaging (MRI). The patients' clinical and familial histories were carefully analyzed, and their electroclinical features and course of epilepsy followed for periods ranging from 10 months to 22 years. The electroclinical data were compared with those of previously reported PNH cases.

RESULTS

The patients were subdivided into those with bilateral (7) and unilateral (10) PNH. The former were mainly characterized by structural abnormalities in the posterior cerebral fossa and multiple seizure types; the latter were characterized by the paratrigonal location of the malformation and, frequently, by elementary seizures with a visual or auditory onset. Focal seizures were drug resistant in most cases. The interictal EEG abnormalities were always focal and consistent with the location of the PNH. A previously unreported photic driving of posterior background activity was observed in all patients and was always consistent with the PNH location.

CONCLUSIONS

Our present findings and previously reported data show that bilateral and unilateral PNH cases are different in their morphological and electroclinical features and may be determined by different etiologies. The female predominance, frequent familial occurrence, and positive family history for epilepsy suggest that genetic factors may be involved in the genesis of bilateral and symmetrical PNH, whereas the presence of prenatal risk factors and its location in the watershed paratrigonal area suggest that vascular mechanisms may determine unilateral PNH.

Expression of the SMN gene, the spinal muscular atrophy determining gene, in the mammalian central nervous system

The survival motor neuron (SMN) gene is the putative disease gene for human spinal muscular atrophy (SMA), an autosomal recessive disorder characterized by progressive degeneration of lower motor neurons. Two copies of the gene, centromeric and telomeric, are present in the same 5q13 chromosomal region in humans. However, only the telomeric gene is affected in SMA. The SMN gene(s) encode(s) a novel protein of unknown function. To gain insights into the role of SMN in neurons, we have identified the SMN gene ortholog in the rat, and investigated SMN expression in the CNS of rat, monkey and humans by immunocytochemistry and in situ hybridization experiments. Antibodies against the SMN amino-terminus specifically recognized a single protein identical to the in vitro translation products of human and rat SMN cDNAs. The SMN gene transcript and product were widely but unevenly expressed throughout cerebral and spinal cord areas. The SMN protein was localized mainly in the cytoplasm of specific neuronal systems, and it was particularly expressed in lower motor neurons of newborn and adult animals. Likewise, a strong hybridization signal was detected in lamina IX of the spinal ventral horn. These results support the relevance of SMN for the motor neuron function and the pathogenetic role of the SMN gene in the neuronal degeneration associated with SMA.

Autoradiographic evidence for differential G-protein coupling of 5-HT1A receptors in rat brain: lack of effect of repeated injections of fluoxetine

The present study examined the distribution of [3H]8-OH-DPAT-labeled 5-HT1A receptors and their degree of coupling to G proteins in the hypothalamus and several other brain regions. In addition, we also investigated the effects of repeated injections of fluoxetine on the density and G protein coupling of 5-HT1A receptors in hypothalamic nuclei and other brain regions using autoradiography. Male rats received daily injections of either fluoxetine (10 mg/kg, ip) for 3, 7, 14 and 22 days, or saline for 22 days. 5-HT1A receptors were labeled by 2 nM [3H]8-hydroxy-2-(dipropylamino)tetralin ([3H]8-OH-DPAT) in the absence or presence of guanylylimidodiphosphate (Gpp(NH)p, 10[-5] M) to determine the percentage of 5-HT1A receptors coupled to G proteins. 5-HT1A receptor densities ranged from 7 to 63 fmol/mg tissue equivalent among hypothalamic nuclei. Similarly, the degree of G protein coupling to 5-HT1A receptors varied markedly among hypothalamic nuclei (from 14% to 61%) and among other brain regions (from 17% to 85%). Fluoxetine did not alter the density or the degree of coupling of 5-HT1A receptors in any brain regions. These data indicate marked regional differences in the degree of G protein-coupled 5-HT1A receptors and suggest that fluoxetine-induced desensitization of hypothalamic 5-HT1A receptors is not mediated by changes in receptor density or G protein coupling.

A desensitization of hypothalamic 5-HT1A receptors by repeated injections of paroxetine: reduction in the levels of G(i) and G(o) proteins and neuroendocrine responses, but not in the density of 5-HT1A receptors

The aim of the present study was to determine whether the previously observed desensitization of hypothalamic 5-hydroxytryptamine1A (5-HT1A) receptors, during daily injections of fluoxetine, is mediated by sustained blockade of 5-HT reuptake. In the present study, we examined the time course effects of another 5-HT uptake inhibitor, paroxetine. Paroxetine reduced the oxytocin, adrenal corticotropic hormone and corticosterone responses to a challenge with the 5-HT1A agonist 8-hydroxy-2-(dipropylamino)tetralin. These reductions in hormone responses were significant after 3 daily injections and reached a maximum after 7 daily paroxetine injections. These hormone responses remained maximally suppressed after 14 daily injections of paroxetine. A single day of paroxetine treatment did not alter the hormone responses to 8-hydroxy-2-(dipropylamino)tetralin. Repeated injections of paroxetine did not reduce the density of 5-HT1A receptors in any brain region but did produce a gradual reduction in the levels of G(i) and G(o) proteins in a region-specific manner. The time course of the paroxetine-induced reduction in the level of G(i1) and G(i3) proteins in the hypothalamus was similar to the effect previously observed with fluoxetine and was also similar to the time course of paroxetine-induced reductions in oxytocin and adrenal corticotropic hormone responses to 8-hydroxy-2-(dipropylamino)tetralin. In conclusion, these results suggest that blockade of 5-HT uptake sites produces a delayed and gradual desensitization of 5-HT1A receptors in the hypothalamus. This desensitization is not due to changes in the density of hypothalamic 5-HT1A receptors. Reduction in the hypothalamic level of G(i3) proteins may play a role in the desensitization of 5-HT1A receptor systems. However, reductions in G(i1) or G(o) proteins cannot be excluded as potential mediators of the desensitization of 5-HT1A receptor systems.

In vivo inhibition of veratridine-evoked release of striatal excitatory amino acids by the group II metabotropic glutamate receptor agonist LY354740 in rats

In vivo microdialysis in freely moving rats was used to investigate the presynaptic mechanisms by which LY354740, a novel, potent, selective, and systemically active agonist for group II metabotropic glutamate receptors (mGluRs), alters glutamate neuronal transmission. Basal levels of glutamate and aspartate in striatal dialysates of LY354740 (10 mg/kg i.p.)-treated animals were not significantly different from the saline-treated control animals. In the saline treated controls, veratridine (100 microM) induced a 6-fold increase in glutamate and 9-fold increase in aspartate. However, following LY354740 administration the veratridine-evoked release of glutamate and aspartate was completely prevented. These data demonstrate that LY354740 blocks the evoked release of endogenous excitatory amino acids, and indicate a role for group II mGluRs in presynaptic modulation of glutamate neuronal transmission in vivo. Ireland Ltd.

A number of schizencephaly patients including 2 brothers are heterozygous for germline mutations in the homeobox gene EMX2

We report here that some patients affected by schizencephaly are heterozygous for mutations in EMX2, a homeobox gene implicated in the patterning of the developing forebrain. Schizencephaly is a very rare human congenital disorder characterized by a full-thickness cleft within the cerebral hemispheres. Large portions of these may be absent and replaced by cerebrospinal fluid. We previously reported the presence of EMX2 mutations in 7 out of 8 sporadic cases of schizencephaly. We now extend this analysis to 10 additional patients, including 2 brothers. Six patients were found to be heterozygous for de novo mutations in EMX2. In particular, the 2 brothers show the same mutation affecting the splicing of the first intron, while this mutation is absent in their parents and in the 2 unaffected siblings.

Function and organization in dysgenic cortex. Case report

Cerebral dysgenesis is a subject of interest because of its relationship to cerebral development and dysfunction and to epilepsy. The authors present a detailed study of a 16-year-old boy who underwent surgery for a severe seizure disorder. This patient had dysgenesis of the right hemisphere, which was composed of a giant central frontoparietal nodular gray matter heterotopia with overlying large islands of cortical dysplasia around a displaced central fissure. Exceptional insight into the function, biochemistry, electrophysiology, and histological structure of this lesion was obtained from neurological studies that revealed complementary information: magnetic resonance (MR) imaging, [18]fluoro-2-deoxy-D-glucose positron emission tomography (PET), functional PET scanning, proton MR spectroscopic (1H-MRS) imaging, intraoperative cortical mapping and electrocorticography, in vitro electrophysiology, and immunocytochemistry. These studies demonstrated compensatory cortical reorganization and showed that large areas of heterotopia and cortical dysplasia in the central area may retain normal motor and sensory function despite strikingly altered cytoarchitectonic organization and neuronal metabolism. Such lesions necessitate appropriate functional imaging studies prior to surgery and cortical mapping to avoid creating neurological deficits. Integrated studies, such as PET, 1H-MRS imaging, cortical mapping, immunocytochemistry, and electrophysiology may provide information on the function of developmental disorders of cerebral organization.

[Imaging of laryngotracheal stenoses in early and stabilized phases]

The contribution of new imaging modalities in the evaluation of laryngo-tracheal stenoses has been growing in recent years. This is due of the possibility of better investigate lesions which are difficult to assess by physical evaluation and of better identify the spread to the deep structures of malignant lesions. Congenital lesions require a chest x-ray as a first step examination, followed by an MRI study or a spiral CT study in order to identify vascular anomalies or mediastinal masses. Inflammatory stenoses are usually investigated by CT, while MRI seldom adds new data to those demonstrated by CT. The latter is mandatory in all traumatic stenoses because it allows an easy identification of fractures or dislocation of cartilages and hyoid bone. Scarring stenoses due to intubation or tracheotomy are also investigated by CT. CT or MRI are essential for the study of neoplastic stenoses. In these patients an ultrasound study and is also recommended permits the identification of abnormal lymphnodes and their US-guided fine needle aspiration. Stenoses due to compression originating from external structures require conventional studies of chest, trachea and esophagus. In these patients the differential diagnosis is reached by means of US, CT or MRI, according to the information provided by conventional studies. Finally, spiral CT is considered the most valuable tool to investigate and to plan the treatment in all the lesions which can undergo endoscopic therapy.

MR of malignant nasosinusal neoplasms. Frequently asked questions

This paper focuses on the role of MR imaging of malignant neoplasms through a particular layout that emphasizes: (a) the rationale for the application of imaging; (b) the factors influencing the selection of sequences, planes and their proper arrangement; (c) the correlation between MR findings, imaging staging and clinical decision making. Since in most cases surgery is the treatment of choice, the precise assessment of the local extent and spread of tumour plays a key role in planning the surgical approach and influences either the therapy and the prognosis. However, the degree of spatial/anatomical detail required in treatment planning significantly differs between surgery and radiotherapy. Planning of the examination technique focuses on: (a) assembling sequences and planes in the shortest time possible; (b) the solution of specific problems: distinction between neoplasm and retained secretions within nasosinusal cavities; staging of submucosal spread toward the anterior cranial fossa, the orbit, the pterygo-palatine and superior orbital fissures. Since the most effective barrier to spread of neoplasms beyond sinusal walls does not depend on the mineral content of bone, but on the periosteum, assessment of the integrity of periorbita or dura mater is an essential information. Although MR cannot detect focal erosions of the thin sinusal walls, it reliably demonstrates both residual barriers (periorbita and dura), even though the bone has been completely destroyed. However, the final decision concerning orbital exenteration is made according to intraoperative staging. MR imaging can accurately precise the degree of anterior cranial fossa involvement. Furthermore, since either MR and CT accurately indicate the need to perform an anterior craniofacial resection and adequately exclude neoplastic invasion requiring orbital exenteration, more comparative studies are required to demonstrate that MR preoperative staging of nasosinusal malignancies is cost-effective.

Familial schizencephaly associated with EMX2 mutation

We describe two brothers aged 8 and 10 affected by severe bilateral schizencephaly, carrying an identical point mutation of the homeobox gene EMX2. Both children had severe neurologic deficits and mental retardation, although they differed in the anatomic extent of the brain malformation and in the severity of the clinical picture. The present findings, together with the reported cases of schizencephaly associated with EMX2 mutations, support the hypothesis that, at least in some cases, schizencephalies are determined by deleterious mutations of this homeobox gene. The different morphoclinical pictures suggest that, besides the EMX2 mutation, other factors are relevant in determining the severity of the brain malformation and clinical picture.

[Cholecysto-colic fistula: laparoscopic treatment]

Cholecystocolic fistula is an unusual complication of biliary tract disease and it may defeat laparoscopic treatment. We recently was a patient who, while undergoing laparoscopic cholecystectomy, was found to have a fistula between the gallbladder and the transverse colon. The fistula was transected with a 3 cm endoscopic linear stapling device and uneventful laparoscopic cholecystectomy was performed. This report shows that, with increasing experience, no absolute contraindications exist to starting laparoscopic cholecystectomy by introducing the laparoscope.

Calretinin in the thalamic reticular nucleus of the rat: distribution and relationship with ipsilateral and contralateral efferents

In order to investigate the existence of anatomical subdivisions within the thalamic reticular nucleus (Rt), the distribution of reticular neurons expressing the calcium binding protein calretinin was investigated in the rat by means of immunocytochemistry. Calretinin immunoreactive (Cr-ir) neurons were mainly distributed in the lateral and ventral regions, and along the medial border of the Rt rostral pole. Caudal to the rostral pole, many neurons were Cr-ir in the more dorsal part of the rostral two-thirds (the "dorsal cap") of the Rt. Fewer Cr-ir neurons were present more caudally along the lateral and medial borders, and in the caudalmost part of the nucleus, related to the acoustic thalamus. The distribution of Cr-ir neurons in the rostral Rt was compared with that of neurons projecting to the ipsilateral and contralateral anterior, intralaminar, midline, and mediodorsal nuclei, or to the contralateral rostral Rt. The retrograde transport of Fluorogold revealed a remarkably precise topography of the rostral Rt: different reticular areas were found to project to different thalamic nuclei, or to different rostrocaudal or mediolateral portions of the same thalamic nucleus, with a limited degree of overlap. The double-labeling experiments demonstrated that the reticular neurons projecting to the ipsilateral anterodorsal, midline, mediodorsal, and anterior intralaminar nuclei frequently expressed calretinin; by contrast, the majority of the reticular commissural neurons did not express the protein, with the exception of neurons projecting to the contralateral mediodorsal and midline nuclei. The ipsilaterally projecting calretinin-positive neurons were frequently located along the medial edge of the rostral pole and in the dorsal cap of the nucleus, segregated from the commissural calretinin-negative neurons. The combined analysis of calretinin expression patterns and tract tracing data provided further insight in the anatomical organization of the thalamic reticular nucleus, suggesting a different neurophysiological role for the ipsilaterally vs. the contralaterally projecting reticular neurons in the modulation of the synaptic activity of the dorsal thalamus.

CT appearance of the larynx after conservative and radical surgery for carcinomas

The purpose of this study was to evaluate the normal CT appearance of the larynx after conservative and radical surgery. Postoperative (conservative surgery n = 52, radical surgery n = 21) CT examinations of 73 patients suspected of local/regional recurrence (n = 53) or asymptomatic (n = 20) were retrospectively analysed. The CT findings of 45 patients negative at biopsy were utilised to assess the normal appearance after surgery. Changes in the laryngeal framework represented constant landmarks, whereas the variety of soft tissues resection often resulted in a more unpredictable appearance of the neolarynx. Considerable thickening of the mucosa covering the arytenoid cartilage(s) has been detected after horizontal supraglottic laryngectomy (40 %) or supracricoid laryngectomies (SL; 100 %). A "pseudocord" due to scar tissue appeared to be a constant finding following vertical haemilaryngectomy, frequently after SL. Dilation of a lateral recess of the hypopharynx was observed after SL. This "pharyngeal pouch" had considerable size and air or liquid content. The most frequent CT findings among 28 tumours recurrent after conservative or total surgery were a mass larger than 10 mm spreading beyond the larynx (63.1 %), thickening of anterior commissure (57.9 %), erosion of residual cartilages (16.9 %). Although CT detected one subclinical recurrence, its employment is justified only to assess the submucosal extent of the lesion. This requires a thorough knowledge of normal postoperative findings.