Assessment relationship between the femoral artery vasospasm and dorsal root ganglion cell degeneration in spinal subarachnoid hemorrhage: an experimental study.

STUDY DESIGN: Animal proof of principle study. OBJECTIVES: To investigate neurodegeneration in rabbit L4-dorsal root ganglion (DRG) cells by creating experimental spinal subarachnoid hemorrhage (SAH), we aimed to show the neuronal pathway between L4-DRG and femoral artery. SETTING: Ataturk University, Medical Faculty, Animal Laboratory, Erzurum, Turkey. METHODS: This study was designed on 20 rabbits, which were randomly divided into three groups: Spinal SAH (n = 8), SHAM (n = 6), and control (n = 6) groups. Animals were followed for 20 days and then killed. Vasospasm index values of the femoral artery and neuron density of L4-DRG were analyzed. RESULTS: The number of degenerated neurons in DRG was higher in the spinal SAH than the control and SHAM groups (p < 0.001). But, the difference between the control group and the SHAM group was not significant. Normal neuron densities were significantly lower in the spine SAH group compared to the SHAM and the control groups. There was a statistically significant increase in vasospasm index values of the spinal SAH group compared to the other two groups (p < 0.001). CONCLUSIONS: Decreased volume of the femoral artery lumen was showed in animals with spinal SAH compared with control and SHAM groups. Increased degeneration of the L4 dorsal root ganglion in animals with spinal SAH was also demonstrated. Our findings might shed light on the planning of future experimental studies and evaluating the clinical relevance of such studies.

Estimating basilar artery upper rupture limit by dangerous alarming diameter of arteries (DADA) following bilateral common carotid artery ligation; a new theorem.

BACKGROUND: Although many theories have been established to explain the mechanism of aneurysm development following steno-occlusive or hypertensive disease, the effect of the geometrical shape of the inner elastic membrane on the maximum dilatation capacity of arteries has not been adequately investigated so far. This subject was investigated. METHODS: This study was conducted in 24 rabbits. The rabbits were divided into 3 groups: as the control, (n = 5), the SHAM (n = 5), and the study group (n = 14). In the study group, BCCAL was performed. After decapitation, the basilar artery vasodilatation index (VDI) and the actual length of the inner elastic membrane (IEM) were estimated. The relationship between the true length of IEM and VDI values was compared statistically using the Mann-Witney -U test. RESULTS: Mean blood pressures were 113 ± 7 mmHg in animals at the beginning of the experiment (n = 24), and 119 ± 9 mmHg in GII and 122 ± 11mmHg in GIII after BCCAL (n = 12). Before decapitation, the mean blood pressures were 115 ± 10 mmHg in GI, 116 ± 10 mmHg in GII, and 127 ± 11mmHg GIII. The DADA values of animals were 20 ± 4mm in GI; 28 ± 6mm in GII and 37 ± 9mm in GIII. The VDI value of BA was 1.390 ± 0.220 in GI; 1.013 ± 0.108 in GI; 0.019 ± 0.011in GII group. CONCLUSION: An inverse relationship was discovered between the DADA/VDI values. BCCAL may lead to severe dangerous histopathological changes at the BA. Lower DADA or higher VDI values may lead to severe basilar enlargement, endothelial losing, inner elastic membrane rupture, and aneurysm formation after BCCAL.

New experimental finding of dangerous autonomic ganglia changes in cardiac injury following subarachnoid hemorrhage; a reciprocal culprit-victim relationship between the brain and heart.

OBJECTIVE: The vagal, stellate, and cardiac ganglia cells changes following subarachnoid hemorrhage (SAH) may occur. This study aimed to investigate if there is any relation between vagal network/stellate ganglion and intrinsic cardiac ganglia insult following SAH. MATERIALS AND METHODS: Twenty-six rabbits were used in this study. Animals were randomly divided as control (GI, n = 5); SHAM 0.75 cc of saline-injected (n = 5) and study with autologous 1.5 cc blood injection into their cisterna magna(GIII, n = 15). All animals were followed for three weeks and then decapitated. Their motor vagal nucleus, nodose, stellate, and intracardiac ganglion cells were estimated by stereological methods and compared statistically. RESULTS: Numerical documents of heart-respiratory rates, vagal nerve- ICG, and stellate neuron densities as follows: 276 ± 32/min-22 ± 3/min-10.643 ± 1.129/mm3-4 ± 1/mm3-12 ± 3/mm3 and 2 ± 1/cm3 in the control group; 221 ± 22/min-16 ± 4/min-8.699 ± 976/mm3-24 ± 9/mm3-103 ± 32/mm3 and 11 ± 3/cm3 in the SHAM group; and 191 ± 23/min-17 ± 4/min-9.719 ± 932/mm3-124 ± 31/mm3-1.542 ± 162/mm3 and 32 ± 9/cm3 in the SAH (study) group. The animals with burned neuro-cardiac web had more neurons of stellate ganglia and a less normal neuron density of nodose ganglia (p < 0.005). CONCLUSION: Sypathico-parasympathetic imbalance induced vagal nerve-ICG disruption following SAH could be named as Burned Neurocardiac Web syndrome in contrast to broken heart because ICG/parasympathetic network degeneration could not be detected in classic broken heart syndrome. It was noted that cardiac ganglion degeneration is more prominent in animals' severe degenerated neuron density of nodose ganglia. We concluded that the cardiac ganglia network knitted with vagal-sympathetic-somatosensitive fibers has an important in heart function following SAH. The neurodegeneration of the cardiac may occur in SAH, and cause sudden death.

First emerging evidence of the relationship between Onuf's nucleus degeneration and reduced sperm number following spinal subarachnoid haemorrhage: Experimental study.

Lumbosacral pathologies can lead to infertility. Onuf's nucleus changes in these pathologies may have a role in low sperm number. This study aims to investigate the relationship between Onuf's nucleus degeneration and sperm number following spinal subarachnoid haemorrhage. 22 rabbits were used. They were divided into three groups; five of them were used as the control (GI), five as the SHAM (GII) and twelve as the study groups (GIII). The study group received 0.7 ccs autologous blood into the spinal subarachnoid space at the T12-L1 level. After two weeks, all animals were decapitated, and S1-S3 laminectomy was done. Neurodegenerative changes of Onuf's nucleus, pudendal ganglia (S3) following two weeks after spinal SAH, were examined; sperm numbers were calculated. Degenerated neuron density of the Onuf's nucleus (n/mm3 ), the pudendal ganglia (S3) (n/mm3 ) and mean sperm numbers were calculated as 5 ± 2, 8 ± 3/mm3 and 98.345 ± 12.776/mm3 in the control (GI), 20 ± 5/mm3 , 243 ± 66/mm3 and 91.841 ± 9.654/mm3 in the SHAM (GII), 143 ± 39/mm3 , 2,350 ± 320/mm3 and 68.549 ± 5.540/mm3 in the study group (GIII). In conclusion, there were statistically significant differences between groups. Onuf's nucleus may be responsible for decreased sperm number following spinal SAH.

A new experimental evidence that olfactory bulb lesion may be a causative factor for substantia nigra degeneration; preliminary study.

Background: Anosmia has been considered as the first diagnostic criteria of Parkinson disease (PD), we investigated the effect of the olfactory bulbectomy (OBX) on histopathological features of the substantia nigra in an animal model.Methods: Twenty-seven male rats were used in this study. Animals were divided into three groups as five (control), six SHAM and sixteen study (OBL) groups. Nothing was done in the control group, the only burr hole was done in the SHAM group, OBL was not applied, and bilateral OBL was performed in the study group, and followed ten weeks, then animals were decapitated. Olfactory bulb volumes were measured by macro anatomically. The olfactory bulbs and substantia nigra sections were analyzed by a stereological method to evaluate olfactory glomerulus and neuron density of substantia nigra per cubic centimeter and compared with statistically.Results: The mean olfactory bulb volume, degenerated olfactory glomerulus density and degenerated neuron density of substantia nigra were measured as:(4.14 ± 0.20) mm3, (1 ± 1)/mm3 and (7 ± 2)/mm3 in control (Group I); (3.6 ± 0.16)/mm3, (4 ± 1)/mm3 and(32 ± 7)/mm3 in SHAM (Group II) and (2.2 ± 0.9)/mm3, (112 ± 18)/mm3 and (1543 ± 115)/mm3in study group (Group III). Diminished olfactory bulb volume was observed in Group III animals.Conclusions: We concluded that OBL may lead to the degeneration of substantia nigra.

A Rare Neurologic Disease that Mimics Cranial Hydatid Cyst: Leukoencephalopathy, Cerebral Calcifications, and Cysts.

A 33-year-old male patient was admitted to the clinic with seizures and progressive neurologic symptoms. In the family history of the patient, a first degree relative had a history of hydatid cyst surgery. Cranial computed tomography images showed intracranial cysts and calcifications. Thus, it was suspected that it might be hydatid cyst. However, the patient was diagnosed with leukoencephalopathy with intracranial calcifications and cysts, a rare neurologic entity by advanced radiologic imaging, serologic and pathologic evaluation.

Olfactory bulbectomy and raphe nucleus relationship: a new vision for well-known depression model.

Background/aim: The olfactory bulbectomy (OBX) technic is a well-known animal model for depression. According to serotonin hypothesis of depression, one of the possible explanations to this mechanism is the destroying effect of OBX on raphe nuclei which especially include serotonergic neurons. In this study, we aimed to explore histopathological findings in raphe nuclei in OBX rats.Materials and methods: Forty-eight rats (8 control group, 10 sham group, and 30 as the study group) were used. No procedure was applied to the control group. Only frontal burr holes were performed at the level of olfactory bulbs (OBs) on the sham group. Mechanical OBX by compression was applied to 20 rats and the OBs of 10 rats were cauterized. Their OBs, olfactory cortices, raphe nuclei were extracted, tissue specimens were taken than examined by using histopathological methods including hematoxylin and eosin, S-100, and TUNEL staining. Physical dissector method was used to evaluate the number of living and apoptotic neurons in the raphe nuclei.Results: Prominent neuronal loss and morphological changes in the dorsal raphe nuclei were detected in study groups.Conclusion: Raphe nuclei degeneration, related alterations in neurotransmitter system activities and functional brain connectivity might be related to neurobiology of depression.

First emerging objective experimental evidence of hearing impairment following subarachnoid haemorrhage; Felix culpa, phonophobia, and elucidation of the role of trigeminal ganglion.

Objective: The exact mechanism of phonophobia induced by subarachnoid hemorrhage (SAH) has not been understood well. This subject was investigated. Material and methods: This study was conducted on 25 rabbits. They divided into three groups: Five as control, five as SHAM, 20 as SAH group. All animals objected to 85 dB impulse noise by daily periods, and their phonophobic score values were examined by daily periods for 20 days. Their brains, trigeminal ganglia were extracted bilaterally. The normal and degenerated neuron densities of trigeminal ganglia were examined by stereological methods and compared with phonophobia scores. Results: Phonophobic score was 19-17, mean live neuron density (LND) of the trigeminal ganglia was 16.321 ± 2.430/mm3, and degenerated neuron density (DND) was 1.15 ± 0.120/mm3 in animals of control groups (n = 5). The phonophobic score was 17-14, LND: 14.345 ± 1.913/mm3, DND of the trigeminal ganglia was 1.150 ± 0.110/mm3 in SHAM group (n = 5). The phonophobic score was 14-8, LND: 12.987 ± 1.966/mm3, mean DND of the trigeminal ganglia was 2.520 ± 510/mm3 in animals with high phonophobia scores (n = 6). The phonophobic score was 7-4, LND: 9.122 ± 1.006, mean DND of the trigeminal ganglia was 5.820 ± 1.610/mm3, in animals with fever phonophobia scores (n = 9). Conclusion: An inverse relationship between DND trigeminal ganglion (TGG) and phonopobic score was found. The paralysis of tensor tympani muscle owing to trigeminal ganglia ischemia may be responsible for phonophobic clinical state in animals with SAH. In addition, there seems to be an important concern for the verbal component of GCS in SAH. These two important findings have not been published previously.

Disruption of the network between Onuf's nucleus and myenteric ganglia, and developing Hirschsprung-like disease following spinal subarachnoid haemorrhage: an experimental study.

Purpose/Aim of the study: Auerbach/Meissner network of lower abdominopelvic organs managed by parasympathetic nerve fibres of lumbosacral roots arising from Onuf's nucleus located in conus medullaris. Aim of this study is to evaluate if there is any relationship between Onuf's nucleus ischemia and Auerbach/Meissner network degeneration following spinal subarachnoid haemorrhage (SAH). Materials and Methods: Study was conducted on 24 male rabbits included control (Group I, n = 5), serum saline-SHAM (Group II, n = 5), and spinal SAH (Group III, n = 14) groups. Spinal SAH performed by injecting homologous blood into subarachnoid space at Th12-L4 level and followed three weeks. Live and degenerated neuron densities of Onuf's nucleus, Auerbach and Meissner ganglia (n/mm3) were determined by Stereological methods. Results: The mean degenerated neuron density of Onuf's nucleus was significantly higher in Group III than in Groups I-II (152 ± 26, 2 ± 1 and 5 ± 2/mm3 respectively, p < 0.005). The degenerated neuron density of Auerbach's ganglia was significantly higher in Group III than in Groups I-II (365 ± 112, 3 ± 1 and 9 ± 3/mm3 respectively, p < 0.005). The degenerated neuron density of Meissner's ganglia was significantly higher in Group III than in Groups I-II (413 ± 132, 2 ± 1 and 11 ± 4/mm3 respectively, p < 0.005). Conclusions: Onuf's nucleus pathologies should be considered as Auerbach/Meissner ganglia degeneration and also related Hirschsprung-like diseases in the future.

Water-Filled Vesicles of Choroid Plexus Tumors.

OBJECTIVE: Choroid plexus cysts are the most common neuro-epithelial cysts. METHODS: The authors describe 2 cases. The first case is a 1-year-old child presenting with hydrocephalus and cyst of the choroid plexus. The child was treated with endoscopic fenestration of the cysts. RESULTS: The histological examination of the cyst wall was consistent with choroid epithelium and water-filled vesicles. The second case is a 63 year old male with a highly vascularized tumor extending to choroid plexus. A quaductus Silvius was obstructed by the tumor. The histopathologic examination of choroid plexus showed a low number, water-vesicles. CONCLUSIONS: According to our knowledge, there are no previous reports of water-filled vesicles with choroid plexus cyst causing hydrocephalus. The first case is a good example of over secretion of cerebrospinal fluid (CSF) with the water-filled vesicle. The second case with low number of water filled vesicle shows that the cause of hydrocephalus is not over production of CSF, it is blockage of the CSF pathway in Aquaductus Silvius by the tumor itself. These 2 cases are illustrative and more importantly highlight the need to study for water-filled vesicles in these kind of cases.

The sooth beneath the taste roseas in the urethra and first description of neuro-morpho-chemical mechanism of penile erectile posture in males: an experimental study.

AIM: The morphologic mechanism of orgasmic sensation has not yet been understood. Taste roseas may be stimulated by fructose via pudendal nerves, which has not been studied yet. METHODS: In this study, 27 male adult rabbits were used, which were divided into three groups: 5 as control; 5 as SHAM and 17 used as study group. We injected 0.2 cc of distilled water to SHAM and 0.2 cc of fructose solution to the study group of their urethral orifices, and examined the occurrence of penile erection. The relationship between erection and pudendal nerve ganglia and penile tissues was statistically compared. RESULTS: In animals with high neuron density of pudendal ganglia, more erection phenomenon was observed than those animals with low neuron density. Interestingly, neuron density of pudendal ganglia was 9.243 ± 542 /mm3 in hypoactive and was 5.980 ± 463 /mm3 in non-active animals (p < 0.05). CONCLUSIONS: The seminal fructose may stimulate taste roseas of the urethra and glans penis via pudendal nerves. The present study describes a new neuro-morpho-chemical mechanism of orgasmic sensation with its neurosurgical aspect.

A New Technique in Surgical Management of the Giant Cerebral Hydatid Cysts.

OBJECTIVES: In hydatid disease, the central nervous system is affected approximately in 2% to 3% of patients. Surgical management in these patients is important. To develop a surgical technique to avoid the formation of great volume of cavity after hydatid cyst removal and prevent complications associated with brain collapse and cortical convolution. PATIENTS AND METHODS: In 2 patients, hydatid cysts were delivered by this new technique. A balloon filled with 150 cc of sterile air/distilled water was placed in the cavity until the balloon filled the entire cavity. Air/distilled water evacuation was continued at a rate of 20 cc/d and, after a week, eventually, the balloons were removed RESULTS:: All cysts were delivered without rupture. Neurologic outcomes were good. No complications were observed related to usage of the system such as balloon rupture, evacuation problems, and infection. CONCLUSION: The authors believe that the balloon insertion technique may be a useful method to prevent brain collapse, cortical convolution, and complications associated with this condition. Further technical refinements of the system are needed for better results.

Changes in number of water-filled vesicles of choroid plexus in early and late phase of experimental rabbit subarachnoid hemorrhage model: the role of petrous ganglion of glossopharyngeal nerve.

BACKGROUND: Cerebrospinal fluid (CSF) secretion may be increased in the early phases of subarachnoid hemorrhage (SAH), possibly via ischemic glossopharyngeal nerve discharges, and decreased due to glossopharyngeal nerve degeneration in the late phase of SAH; but this reflex pathway has not been definitively investigated. We studied the relationship between petrous ganglion of the glossopharyngeal nerve (GPN) and water vesicles of the choroid plexus (CP) in the early and late phases of SAH. METHODS: This study was conducted on 30 rabbits, divided into four groups, with five rabbits in the control group (group I), five rabbits in the sham group (Group II), and 20 rabbits in the SAH group. In the SAH group, five of the animals were decapitated after 4 days of cisternal blood injections (Group III), and the other 15 animals were decapitated after 20 days of injections (Group IV). The Petrous Ganglia and CPs of lateral ventricles were removed and stained for stereological analysis. RESULTS: The mean number of follicles per cubic millimeter was 5.3 ± 1.2 the in control group (Group I), 4.5 ± 0.9 in the sham group (Group II), 16.60 ± 3.77 the in early decapitated group (Group III), and 4.30 ± 0.84 in the late decapitated group (Group IV). The mean number of degenerated neuron density of petrous ganglions was 6 ± 2, 50 ± 6, 742 ± 96, and 2.420 ± 350 in the control (Group I), sham (Group II), early decapitated (Group III), and late decapitated group (Group IV), respectively. The mean number of water vesicles was statistically different after SAH between the early decapitated group (group III) and the late decapitated group (group IV) (P < 0.05). CONCLUSIONS: We studied the relationship between petrous ganglion cells of the GPN and water vesicles of CP in the early and late phases of SAH, and found that CP vesicles are increased in the early phase of SAH due to irritation of GPN, and decreased in the late phase due to ischemic insult of the petrous ganglion and parasympathetic innervation of the CP.

The role of sympathectomy on the regulation of basilar artery volume changes in stenoocclusive carotid artery modeling after bilateral common carotid artery ligation: an animal model.

BACKGROUND: Stenoocclusive carotid artery disease causes important histomorphologic changes in all craniocervical vasculatures, such as luminal enlargement, vascular wall thinning, elongation, convolutions, and aneurysm formation in the posterior circulation. Although increased pressure, retrograde blood flow, and biochemical factors are described in the pathogenesis of vascular remodelisation, the vasoregulatory role of the autonomic nervous system has not been investigated thus far. We investigated the relationship between the sympathetic nervous system and the severity of histomorphologic alterations of basilar arteries after bilateral common carotid artery ligation (BCCAL). MATERIAL AND METHODS: This study was conducted on 21 rabbits. The rabbits were randomly divided into three groups: baseline group (n = 5), sympathectomy non-applied group (SHAM; n = 8), and sympathectomy applied group (n = 8) before bilateral common carotid artery ligation. Permanent ligation of the prebifurcations of the common carotid arteries was performed to replicate stenoocclusive caroid artery disease. Basilar artery volumes were measured after ligation. Volumes of the basilar arteries were estimated by stereologic methods and compared between groups. RESULTS: Luminal enlargement, wall thinning, elongation, convolutions, and doligoectatic configurations were detected in the majority of basilar arteries. The mean basilar arterial volume was 4.27 ± 0.22 mm3 in the baseline group; 5.28 ± 0.67 mm(3) in the SHAM group, and 8.84 ± 0.78 mm3 in the study group. The severity of basilar enlargement was significantly higher in the study group compared with the SHAM (p < 0.005) and baseline groups (p < 0.001). CONCLUSIONS: Sympathectomy causes basilar artery enlargment, which is beneficial for maintaining cerebral blood flow; however, it also causes wall thinning, elongation, convolution, and aneurysm formation, which may be hazardous in stenoocclusive carotid artery disease. Sympathectomy can prevent new vessel formation and hyperthyrophic changes at the posterior circulation. Neovascularisation is not detected adequately in sympathectomised animals.

New Evidence for Regulatory Role of Trigeminal Ganglion on the Intraocular Pressure Following Subarachnoid Hemorrhage.

BACKGROUND: Increased intraocular pressure (IOP) likely secondary to an activated oculo-trigeminal reflex network is an important issue following subarachnoid hemorrhage (SAH). The relationship between the IOP and trigeminal ganglion (TGG) following experimental SAH was investigated in this study. METHODS: Twenty-three rabbits were used in this study. Five rabbits (n = 5) were used as the control group, another 5 as the sham group (n = 5), and the remaining 13 (n = 13) as the study group. The study group was further divided into two groups of animals with mild (n = 6) and severe (n = 7) TGG degeneration. The IOP values were recorded. After 2 weeks, the animals were decapitated. The mean degenerated neuron density of TGGs was estimated by stereological methods and analyzed statistically. RESULTS: The average IOP values were 11.85, 14.12, and 21.45 mm Hg in the control (n = 5), sham (n = 5), and study (n = 13) groups, respectively. The mean degenerated neuron density was 34, 237, and 3,165 mm3 in the control, sham, and study groups, respectively. CONCLUSION: According to the findings of this study, the experimental SAH leads to changes in IOP by affecting the TGG. By predicting and preventing IOP elevation in the setting of SAH, our findings will shed light on secondary sequelae such as glaucoma and irreversible blindness.

First report of the histopathological effect of electrocautery using on the urethral taste rosea during glans penis injury by incision in rabbits.

Objective: Currently, electrocautery devices have frequently been used in penile surgical procedures. We hypothesized that electrocautery using during penile surgical procedures may harm the taste rosea and the dorsal nerve of the penis or clitoris. Methods: Eighteen young age male New Zealand rabbits were studied: five in the control (Group I, n=5), five in the penile surgery without using electrocautery (sham group, Group II, n=5), eight in the monopolar cautery (study group, Group III, n=8) groups under general anesthesia. The animals were followed for 3 weeks and sacrificed. Penile tissue-pudendal nerve root complexes and dorsal root ganglion of sacral 3 level were examined using stereological methods. The results were compared statistically. Results: The live and degenerated taste bud-like structures and degenerated neuron densities of pudendal ganglia (mean±standard deviation, n/mm3) were estimated as 198±24/mm3, 4±1/mm3, and 5±1/mm3 in Group I; 8±3/mm3, 174±21/mm3, and 24±7/mm3 in Group II; and 21±5/mm3, 137±14/mm3, and 95±12/mm3 in Group III, respectively. Neurodegeneration of taste buds and pudendal ganglia was significantly different between groups. Conclusion: Intact spinal cord and normal parasympathetic and thoracolumbar sympathetic networks are crucial for human sexual function. The present study indicates that the glans penis injury by using electrocautery may lead to pudendal ganglia degeneration. Iatrogenic damage to taste rosea and retrograde degeneration of the pudendal nerve may be the cause of sexual dysfunction responsible mechanism.

Interaction between Neurogenic Pulmonary Edema and Thoracic 3 DRG Degeneration Following Spinal Subarachnoid Hemorrhage: First Experimental Study.

BACKGROUND: Neurogenic pulmonary edema (NPE) following subarachnoid hemorrhage (SAH) is still one of the most catastrophic complications with high morbidity and mortality rates. Systemic sympathetic hyperactivity has been considered in the pathogenesis, but it has not been clarified. In this study, we investigate the relationship between the degeneration of the T3 dorsal root ganglion (DRG) and the development of NPE following spinal SAH. METHODS: The study was conducted on 23 rabbits. Five rabbits were used as the control group, 5 as the sham group (n = 5), and 13 as the study group. The correlation between the degenerated neuronal densities of the T3 nerve axons and neurons in the DRG and NPE scores was analyzed statistically. RESULTS: A correlation between the neuronal degeneration of the T3 nerve, its DRG, and high NPE scores was found in the study group and the sham group. Massive NPE was detected in the study group along with neural degeneration of T3 axons and ganglia. CONCLUSION: The present study indicates that NPE and pulmonary artery vasospasm can be prevented by reducing T3 DRG degeneration.

Olfactory bulbectomy leads to prolonged induction phase of sevoflurane anesthesia in rats.

The effect of olfactory bulb lesions on the induction time of sevoflurane has never been studied. We aimed to investigate this issue. In this study, we found that the volume of olfactory bulbs and the pore of the fila olfactoria were significantly lower with the fibrosis of olfactory bulbs in animals subjected to olfactory bulbectomy. Volatile anesthetics induction times were measured in all groups. Prolonged induction was observed in olfactory bulbectomy group. It was concluded that increased induction times of sevoflurane may be due to the olfactory bulb lesion.

Overlooked evidence for transmission deficit of pupillary light reflex can be secondary to trigeminal nerve ganglion degeneration following subarachnoid hemorrhage; preliminary experimental study.

OBJECTIVE: Although the effect of oculomotor and cervical sympathetic networks on pupil diameter is well known; the effect of the trigeminal nerve on pupil diameter has not been investigated yet. This subject was investigated. MATERIALS AND METHODS: Five of 23 rabbits were used as a control group (GI; n = 5); 0.5 ccs saline solution into cisterna magna injected animals used as SHAM (GII; n = 5); autologous blood injected to produce SAH used as the study group (GIII; n = 13) and followed up three weeks. Light-stimulated pupil diameters were measured with an ocular tomography device before, middle, and at the end of the experiment. Considering the sclera area/pupil area ratio index (PRI) as the pupillary reaction area, we used this equation for the pupil's rush to light. Degenerated neuron densities of trigeminal ganglia and pupil diameters compared with the Mann-Whitney U test. RESULTS: The PRI, degenerated neuron density of trigeminal ganglia (n/mm3) were: (2.034 ± 0.301)/(13 ± 3) in GI; (1.678 ± 0.211)/(46 ± 9) in GII; and (0.941 ± 0.136)/(112 ± 21) in GIII. P-values between groups as: p < 0.005 in GI/GII; p < 0.0001 in GII/GIII and p < 0.00001 in GI/GIII. CONCLUSION: Light stimulates the cornea which is innervated by the trigeminal nerves. This experimental study indicates that the pupil remains mydriatic as the cornea is damaged by trigeminal ischemia following SAH and blocks the light flow.

Important Finding for COVID-19 Pandemic: Hydrocephalus-producing effect of Vaporized Alcohol Disinfectant.

BACKGROUND: Alcohol exposure may cause hydrocephalus, but the effect of vaporized nasal alcohol exposure on the choroid plexus, and ependymal cells, and the relationship between alcohol exposure and developing hydrocephalus are not well known. This subject was investigated. METHODS: Twenty-four male (∼380 g) Wistar rats were used in this study. The animals were divided into three groups, as the control, sham and study groups. The study group was further divided into two groups as the group exposed to low or high dose of alcohol. The choroid plexuses and intraventricular ependymal cells and ventricle volumes were assessed and compared statistically. RESULTS: Degenerated epithelial cell density of 22 ± 5, 56 ± 11, 175 ± 37, and 356 ± 85/mm3 was found in the control, sham, low alcohol exposure, and high alcohol exposure groups, respectively. The Evans index was <34% in the control group, >36% in the sham group, >40% in the group exposed to low alcohol dose (low-dose alcohol group), and >50% in the group exposed to high dose of alcohol (high-dose alcohol group). CONCLUSIONS: It was found that alcohol exposure caused choroid plexus and ependymal cell degeneration with ciliopathy and enlarged lateral ventricles or hydrocephalus. In the COVID-19 pandemic era, our findings are functionally important, because alcohol has often been used for hygiene and prevention of transmission of the Sars-Cov-2-virus.