V2 Dermatomes Research Articles

Role of Gamma Knife radiosurgery in trigeminal neuralgia – Its long term outcome and prediction using Artificial neural Network model

PurposeWe aimed to study the long-term efficacy, prognostic factors and complications associated with the GKRS for trigeminal neuralgia. Methods and MaterialsProspectively created database was analyzed for these patients. We created an Artificial neural Network – using Multilayer perceptron model in SPSS 23 by including all variables whose p value were<0.5 in univariate analysis. ResultsA total of 36 patients were included in the study. Patients pain free at 6 months were 25(69.44%), which reduced to 6(40 %) at 6 years. Median time to pain relief was 18.5 days. Only 5(13.88%) of them developed new onset or worsened numbness post Gamma Knife radio surgery. Median radiation dose was 80 Gy (prescribed at 100 percent isodose line). 1st GKT (P value < 0.05) and post GKT numbness (P value < 0.05) were the only factors favouring good outcome.Prior history of MVD was associated with poor pain relief post GKRS although p value was not significant (p = 0.136). ANN model could predict with 90.0 percent accuracy the favourable or unfavourable response on 11 Tested cases. In ANN model, a greater number of Pre GKT medications, previous MVD history, V2 dermatome involvement and negative history of post GKT numbness were negative prognostic factors. ConclusionsLesser number of pre GKRS drugs used, involvement of V1 dermatome, post GKT numbness are favourable prognostic factors. Also, history of failed MVD for trigeminal neuralgia is associated with poor outcome. Repeat GKRS failed to show improvement in BNI grades.

Herpes zoster ophthalmicus-related oculomotor palsy in a pediatric patient

Herpes zoster ophthalmicus (HZO) is a rare form of shingles that typically presents with prodromal symptoms followed by rash along the V1 or V2 dermatomes. Associated ophthalmoplegia is even rarer. About 99% of adults with a history of chickenpox and up to 90% of those without have serology positive for varicella-zoster. Age and immune incompetence are the main risk factors. In the current report, we describe an immunocompetent 16-year-old girl who presented with pupil invoinvolving complete third nerve palsy associated with HZO. After an extensive literature search, we could not find any similar case reported before.

In Reply: Older Patients Have Better Pain Outcomes Following Microvascular Decompression for Trigeminal Neuralgia.

BACKGROUND Trigeminal neuralgia (TN) increases in prevalence with age. Although microvascular decompression (MVD) is the most effective long-term operative treatment for TN, its use in older patient populations has been debated due to its invasive nature. Recent studies have demonstrated safety of MVD in older patients; however, efficacy data are more limited. OBJECTIVE To determine the relationship between age and pain outcomes following MVD for TN. METHODS Subjects underwent MVD for TN at our institution between 1/1/2004 and 12/31/2013, had typical TN, and demonstrated neurovascular compression on preoperative imaging. We performed a retrospective case series study by reviewing the electronic medical records and performing phone interviews to determine long-term outcomes. We divided patients into 2 groups for analysis, under 60 and 60 yr of age and older. RESULTS One hundred twenty-four subjects were included in the study, 82 under 60, and 42 60 yr of age and older. The average length of follow-up was 42.4 mo. Patients in the older age group had average pain score of 1.57 at most recent follow-up, while for the younger age group it was 2.18 (P = .0084). Multiple regression analysis found that older age, male gender, and preoperative medication responsiveness were significantly correlated with lower long-term pain scores, while V2 dermatome involvement was correlated with higher long-term pain scores. CONCLUSION Patients 60 yr of age and older have significantly better long-term pain outcomes following MVD than younger patients.

Older Patients Have Better Pain Outcomes Following Microvascular Decompression for Trigeminal Neuralgia.

Trigeminal neuralgia (TN) increases in prevalence with age. Although microvascular decompression (MVD) is the most effective long-term operative treatment for TN, its use in older patient populations has been debated due to its invasive nature. Recent studies have demonstrated safety of MVD in older patients; however, efficacy data are more limited. To determine the relationship between age and pain outcomes following MVD for TN. Subjects underwent MVD for TN at our institution between 1/1/2004 and 12/31/2013, had typical TN, and demonstrated neurovascular compression on preoperative imaging. We performed a retrospective case series study by reviewing the electronic medical records and performing phone interviews to determine long-term outcomes. We divided patients into 2 groups for analysis, under 60 and 60 yr of age and older. One hundred twenty-four subjects were included in the study, 82 under 60, and 42 60 yr of age and older. The average length of follow-up was 42.4 mo. Patients in the older age group had average pain score of 1.57 at most recent follow-up, while for the younger age group it was 2.18 (P = .0084). Multiple regression analysis found that older age, male gender, and preoperative medication responsiveness were significantly correlated with lower long-term pain scores, while V2 dermatome involvement was correlated with higher long-term pain scores. Patients 60 yr of age and older have significantly better long-term pain outcomes following MVD than younger patients.

Herpes Zoster Involving the Second Division of the Trigeminal Nerve: Case Report and Literature Review

Herpes zoster along the maxillary division of the trigeminal nerve is a rare condition that is caused by reactivation of the varicella zoster virus that resides within the trigeminal ganglion after the primary infection of chickenpox. The disease may be manifested as a toothache during its prodromal stage. The active stage of the disease is characterized by the appearance of a vesicular rash. Postherpetic neuralgia is a common complication of herpes zoster after resolution of the facial and intraoral symptoms. There is increasing evidence for herpes zoster patients to develop stroke later in life. The present case reports the development of herpes zoster maxillaris in a 71-year-old man whose maxillary right canine was diagnosed as pulpal necrosis and symptomatic apical periodontitis and was subsequently treated endodontically by cleaning and shaping and filling the canal space with gutta-percha and an epoxy resin–based sealer. The patient presented 3 days later with midfacial ulceration, desquamation, and crusting as well as intraoral ulceration along the course of the V2 dermatome. After successful treatment with antiviral medication, postherpetic neuralgia developed within the next 2 months. Complete resolution of the neuralgia occurred at the 4-month recall with negligible facial scarring. Herpes zoster may mimic odontogenic pain during the prodromal stage of the disease. Reactivation of the virus has also been implicated in the pathogenesis of pulpal pathoses. These paradoxical facets are of interest to the endodontist and should be considered in the differential diagnosis of the disease.

CT-guided selective percutaneous radiofrequency thermocoagulation via the foramen rotundum for isolated maxillary nerve idiopathic trigeminal neuralgia

OBJECTIVE Although CT-guided selective percutaneous radiofrequency thermocoagulation (PRFT) via the foramen rotundum (FR) has been used in the clinic as a novel successful treatment for isolated, second division (maxillary nerve [V2]), idiopathic trigeminal neuralgia (ITN), there is only very limited related literature published to date. This report aims to provide more detail for physicians about this technique. METHODS Between March 2013 and April 2014, 20 patients with isolated V2 ITN refractory to or intolerant of drug treatment were treated by CT-guided selective PRFT via the FR at the First Affiliated Hospital of Nanchang University. The outcome of pain relief was assessed using the Barrow Neurological Institute (BNI) pain score, and grouped as good (BNI Class I or II, no medication required) and bad (BNI Class III-V, medication required or failed). Recurrence was defined as a relapse to a previous lower level after attainment of any higher level of pain relief. Adverse effects and complications were also monitored and recorded. RESULTS All patients (100%) obtained good pain relief including BNI Class I in 17 patients (85%) and BNI Class II in 3 patients (15%) immediately postoperatively. None of the patients were lost to follow-up. During the mean follow-up period of 24.3 months (range 18-30 months), 2 patients (10%) experienced recurring pain and the mean time until recurrence was 10.5 months (range 8-13 months). No adverse effects or complications occurred except for transient numbness restricted to the V2 dermatome in all patients (100%) and facial hematoma in 3 patients (15%). CONCLUSIONS In the current study, CT-guided selective PRFT via the FR not only achieved absolute selective lesioning to V2, but also helped patients attain successful pain relief with few adverse effects. These limited data suggest that CT-guided selective PRFT via the FR appears to be a feasible, safe, effective, and even relatively ideal treatment for isolated V2 ITN, but these findings need confirmation from further studies.

Needling the pain and comforting the brain: Acupuncture in the treatment of chronic migraine

Chronic migraine (CM) is a disabling complication of migraine. Prevalence is high, disease-related burden is great, and medical and psychiatric comorbidity is considerable. Treatment has been unsatisfactory and rigorous trials specifically targeting CM are rare. Topiramate and botulinum neurotoxin are the only pharmacological treatments that have been proven effective in randomized, placebo-controlled trials (1–6); however, the therapeutic gain (against placebo) is only modest (Table 1). New or complementary therapeutic modalities for CM treatment are needed. Acupuncture is a widely used, non-pharmacological treatment for migraine. Although its use is still controversial, a recent Cochrane systematic review found acupuncture to be as effective as, or possibly more effective than, preventive migraine agents (7). A beneficial effect of acupuncture in migraine prophylaxis was demonstrated in a prospective randomized trial for CM (8). In a 12-week treatment period, a significantly larger decrease in the mean monthly number of moderate/ severe headache days was observed in the acupuncture group compared with the topiramate group ( 10.5 vs. 7.8 days per 4 weeks, p< 0.01). Significant differences favoring acupuncture across multiple efficacy end points, including mean change of headache days, Migraine Disability Assessment Scores (MIDAS), Hospital Anxiety and Depression Scale (HADS) scores, Short Form 36 (SF-36) scores, Beck Depression Inventory II (BDI-II) scores, mean days of acute medication use, 50% reduction in monthly moderate/severe headache days, 50% reduction in monthly headache days, and safety end points were also observed. In the context of the topiramate studies (1,9) and the Phase III Research Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials (4–6), similar beneficial effects were also observed in patients who were overusing acute medications. Does this study identify an alternative choice for CM patients? Probably yes, but the reasons behind the positive effect could be complex. The study was designed according to the guidelines for trials of the prophylactic treatment of CM (10) and had a clearly defined acupuncture treatment procedure following the Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA) recommendations (11), making it possible to replicate the study and provide a basis for comparisons across disciplines. The acupoints chosen are classic acupuncture sites, which correspond to the dermatomal distribution of trigeminocervical complexes: V1 dermatome [Cuanzhu (BL 2) and Yintang (EX-HN 3)], V2 dermatome [Taiyang (EX-HN 5)], and C2 dermatome [Fengchi (GB-20)]. Traditionally, acupuncture has had its own diagnostic system and the acupoints are individualized and tailored for headaches over different meridians. In this study, the benefits from individualized acupuncture are limited by the fixed-site approach. However, even with this trade-off, the acupuncture arm still outweighed the topiramate group. The positive results of this trial seem to provide a rational mechanism linking the intervention with the pathophysiology of migraine; that is, modulating the trigeminal sensory system. While this hypothesis is possible, a second thought is required to interpret the data. The investigators provided several reasons to justify the choice of topiramate as the active comparator instead of control with sham acupuncture; however, none could offset the putatively higher placebo effect caused by the needling procedure in comparison

Surgical treatment of trigeminal neuralgia. Results from the use of glycerol injection, microvascular decompression, and rhizotomia

The study aims to assess the efficacy and safety of surgical treatment of trigeminal neuralgia (TN) in our department and to identify prognostic factors. Seventy patients receiving surgical treatment for TN during the period 2003-2004 were included in this retrospective study. The surgical procedures used were glycerol injection (GI), microvascular decompression (MVD), or rhizotomia (RIZ). All patients were divided into spontaneous onset TN type1 (brief lancinating pain) or TN type 2 (continuous pain component). Two patients had bilateral TN; each side was regarded as a separate case. These 70 patients had a total of 160 interventions (110 GI, 40 MVD, and ten RIZ) performed in the period 1998-2007. Data were obtained by chart review and telephone interview. Patients provided information about pre- and postoperative pain characteristics including subtype, duration, intensity, and the use of antiepileptic drugs. Outcome was evaluated using a pain vector diagram. To quantify self-reported pain, we developed a new vector-based pain diagram. The subtype of TN was shown to be a very important prognostic factor. One year after MVD, 90% of patients with type 1 TN still had positive effect, whereas this was only true in 73% of patients with type 2 TN. After RIZ, the results were 71% and 33% for types 1 and 2, respectively. For comparison, GI had a significant lower effect but if the treatment led to hypoesthesia, 41% continued to have a positive effect 1 year after surgery, compared to only 24% if postoperative sensation was normal. Type 2 TN was found to be dominated by women with left-sided TN outside the V2 dermatome and with a lower probability of a neurovascular conflict. As expected, 1/5 of the cases developed postoperative hypoesthesia in the face following a nerve destructive procedure (RIZ and GI). Using MVD, the risk of serious side effects was about 4%. Complementary and alternative treatment had no general or permanent effect in the investigated population-quite the contrary. Regarding prognosis and outcome, we find that it is very important to classify TN in subgroups (types 1 and 2). Dealing with medically treatment-resistant type 1 TN, MVD and RIZ are reasonably safe and effective interventions. The surgical results dealing with type 2 TN are still very poor. All patients with medically treatment-resistant TN should be offered referral to a neurosurgical unit with experience in treating this painful disease. We recommend using a vector-based pain diagram when evaluating the outcome of multiple interventions.

Tactile Dysgeusia: A New Clinical Observation of Middle Ear and Skull Base Surgery

To describe a new clinical observation of "tactile dysgeusia," a phenomenon associated with otologic and skull base surgery likely caused by injury to the chorda tympani nerve (CTN) or the nervus intermedius (NI) with subsequent aberrant cross-innervation with somatosensory fibers in the surgical field. Descriptive case series. Tertiary university referral center. Eight patients described a sensation of touch-evoked dysgeusia after surgery. Seven patients underwent a variety of middle ear procedures including stapedotomies and mastoidectomies. One patient had a large cerebellopontine angle meningioma excised through a translabyrinthine approach. There were no preoperatively sensory symptoms of any kind. In five of seven patients who had an otologic procedure, the CTN nerve was transected, whereas in the remaining two, the nerve was preserved but stretched. In the meningioma patient, the facial nerve was preserved without clear identification of the NI; the facial nerve function was normal postoperatively. All of the otologic patients experienced symptoms of dysgeusia and sensory alteration triggered by touching various parts of the outer ear. One also has a secondary trigger in the V2 dermatome. In the meningioma patient, taste and sensory alteration was induced by stimulating the ipsilateral V2 and V3 dermatome. In all patients, the symptom was located in the lateral aspect of the ipsilateral hemitongue. Tactile dysgeusia is an unusual complication after otologic and neurotologic procedures. It is likely related to aberrant re-innervation of the special sensory fibers within the CTN nerve or the NI with somatosensory fibers. Postoperative "tactile dysgeusia" may not be so rare; its true incidence could only be ascertained through a more rigorous postoperative assessment.

Sturge-Weber Syndrome: Age of Onset of Seizures and Glaucoma and the Prognosis for Affected Children

Data were obtained on 171 individuals with Sturge-Weber syndrome via questionnaire and medical records. The age of the study group ranged from 2 months to 59 years; the median was 8 years. In addition to the facial location of port-wine stains in the areas of the trigeminal dermatomes present in 170 patients, 45% also had extracranial port-wine stains over the torso and/or extremities, and 17% had other vascular or pigmentary lesions. Seizures were present in 80% of all patients (87% of those with bilateral and 71% of those with unilateral port-wine stains); in all but one case, seizures were associated with port-wine stains in V1 alone or V1 and V2 trigeminal dermatomes location. The age of onset of seizures ranged from birth to 23 years; 75% had onset of seizures before 1 year of age; these children had an 83% incidence of developmental and academic problems. Fifty-eight percent showed early developmental delay and required special education classes. The rate of retardation showed a decreasing tendency with increasing age of onset of seizures; of the children without seizures, only 6% had developmental delay and 11% required special education classes. Glaucoma was present in 48% of patients (67% unilateral and 33% bilateral). Of all patients with glaucoma, 92% had port-wine stains in both V1 and V2 dermatomes and 8% only in V1. The laterality of glaucoma did not correspond to the trigeminal distribution of the port-wine stains in all instances. Glaucoma was diagnosed during the 1st year of life in 61% and by 5 years in 72%; one patient did not have onset of symptoms until 38 years. The results of our data can serve as a guide for estimating relative risk figures for seizures, glaucoma, and mental retardation in children with Sturge-Weber syndrome.