《内经》曰∶目得血而能视。此一句，圣人论人气血之常也。后世之医，不达其旨，遂有惜
血如金之说。自此说起，目疾头风诸证，不得而愈矣。何以言之？圣人虽言目得血而能视，然血
亦有太过不及也。太过则目壅塞而发痛，不及则目耗竭而失睛。故年少之人多太过，年老之
人多不及。但年少之人，则无不及。但年老之人，其间犹有太过者，不可不察也。
夫目之内
，太阳经之所起，血多气少；目之锐 ，少阳经也，血少气多；目之上网，太阳经也，亦
血多气少；目之下网，阳明经也，血气俱多。然阳明经起于目两旁，交鼻
之中，与太阳、少阳俱会于目。惟足厥阴肝经，连于目系而已。故血太过者，太阳、阳明之实也；血不及者，厥
阴之虚也。故血出者，宜太阳、阳明，盖此二经血多故也。少阳一经，不宜出血，血少故也。
刺太阳、阳明出血，则目愈明；刺少阳出血，则目愈昏。要知无使太过不及，以血养目而已
。此《内经》所谓目得血而能视者，此也。
凡血之为物，太多则益，太少则枯。人热则血行疾而
多，寒则血行迟而少，此常理也。至于目者，肝之外候也。肝主目，在五行属木。然木之为物，太
茂则蔽密，太衰则枯瘁。蔽密则风不疏通，故多摧拉；枯瘁则液不浸润，故无荣华。又况人
之有目，如天之有日月也；人目之有翳，如日月之有云雾也。凡云之兴，未有不因蒸腾而起
者，虽隆冬之时，犹且然耳，况于炎夏之时乎？
故目暴赤肿起，羞明隐涩，泪出不止，暴寒
目瞒，皆工艺之所为也。夫目之五轮，乃五脏六腑之精华，宗脉之所聚。其气轮属肺金，肉
轮属脾土，赤脉属心火，黑水、神光属肾水，兼属肝木，此世俗皆知之矣。及有目疾，则又
不知病之理，岂知目不因火则不病。何以言之？气轮变赤，火乘肺也；肉轮赤肿，火乘脾也；
黑水神光被翳，火乘肝与肾也；赤脉贯目，火自甚也。能治火者，一句可了。故《内经》曰
∶热胜则肿。
治火之法，在药则咸寒，吐之下之；在针则神庭上星、囱会、前顶、百会血之
翳者，可使立退；痛者，可使立已；昧者，可使立明；肿者，可使立消。惟小儿不可刺囟会。为肉
分浅薄，恐伤其骨。然小儿水在上，火在下，故目明；老人火在上，水不足，故目昏。《内
经》曰∶血实者宜决之。又《经》曰∶虚者补之，实者泻之。如雀目不能夜视及内障，暴怒
大忧之所致也。皆肝主目，血少，禁出血，止宜补肝养肾。至于暴赤肿痛，皆宜以
针刺前五穴出血而已，次调盐油以涂发根，甚者，虽至于再、至于三可以也。
量其病势平为期。少白可黑，落发可生，有此神验，不可轻传。人年四十、五十，不问男女，目
暴赤肿，隐涩难开者，以三棱针刺前顶、百会穴，出血大妙。至如年少，发早白落，或白屑者，
此血热而太过也。世俗止知∶发者血之余也，血衰故耳。岂知血热而极，发反不茂？肝者，木也
。火多水少，木反不荣。火至于顶，炎上之甚也。大热病汗后，劳病之后，皆发多脱落，岂有寒
耶？故年衰火胜之人，最宜出血。但人情见出血，皆不悦矣！岂知出血者，乃所以养血也。凡
兔、鸡、猪、狗、酒、醋、湿面，动风生冷等物，及忧忿劳力等事，如犯之则不愈矣。惟后顶、强间、脑户、风
府四穴，不可轻用针灸，以避忌多故也。若有误，不幸令人喑，固宜慎之。其前五穴，非徒
治目疾，至于头痛腰脊强，外肾囊燥痒，出血皆愈。凡针此，勿深，深则伤骨。唐甄权尤得
出血之法。
世俗云∶“热汤沃眼十日明。”此言谬之久矣！火方乘目，更以热汤沃之，两热相
搏，是犹投贼以刃也。岂知凉水沃之，暂涩而久滑；热水沃之，暂滑而久涩。不然，曷以病目者
忌沐浴？或曰∶世俗皆言凉水沃眼，血脉不行。余闻大笑之。眼药中用黄连、硼砂、朴硝、
龙脑、熊胆之属，皆使人血脉不行耶？何谬之甚也。又若头风之甚者，久则目昏，偏头风者，少阳相
火也，久则目束小。大肠闭涩者，目必昏，何也？久病滑泄者，目皆明，惟小儿利久，反疳
眼昏。盖极则反，与此稍异，其余皆宜出血而大下之。余尝病目赤，或肿或翳，作止无时，偶
至亲息帅府间，病目百余日，羞明隐涩，肿痛不已。忽眼科姜仲安云∶宜上星至百会，速以
针刺四、五十刺，攒竹穴、丝竹穴上兼眉际一十刺
两孔内，以草茎弹之出血。三处出血如泉，约二升许，来日愈大半，三日平复如故。余自
叹曰∶百日之苦，一朝而解，学医半世，尚缺此法，不学可乎？惟小儿疮 入眼者，乃余热
不散耳。止宜降心火，泻肝风，益肾水，则愈矣。若大人目暴病者，宜汗、下、吐。以其血在表
，故宜汗；以其火在上，故宜吐；以其热在中，故宜下。出血之与发汗，名虽异而实同，故
录《铜人》中五穴照用。
《黄帝内经》说：眼睛得到血液的滋养才能看见。这一句话，是圣人论述人体气血正常状态的道理。后世的医生，不能理解其中的深意，于是产生了“爱惜血液如同金子一样珍贵”的说法。从这种观点出发，眼疾、头风等各种病症就无法治愈了。为什么这样说呢？圣人虽然说了眼睛得到血液才能视物，但是血液也有过多和不足的情况。血液过多会导致眼部经络壅塞而引发疼痛，血液不足则会导致眼部耗竭失神而视力丧失。所以年轻人多属于血液过多的情况，老年人多属于血液不足的情况。只是年轻人没有血液不足的情况，而老年人中，其间仍有血液过多的，不可不仔细辨别。
眼睛的内眼角，是足太阳膀胱经起始的地方，这里血多气少；眼睛的外眼角，是足少阳胆经所在，这里血少气多；眼睛的上眼睑（上网），属于足太阳膀胱经，也是血多气少；眼睛的下眼睑（下网），属于足阳明胃经，这里气血都多。然而足阳明胃经起于眼睛两旁，交会于鼻根之中，与足太阳、足少阳两经都在眼睛处会合。只有足厥阴肝经，连接着眼系而已。所以血液过多的，是足太阳、足阳明经的实证；血液不足的，是足厥阴肝经的虚证。因此，需要放血的，适宜在足太阳、足阳明经进行，因为这两条经血液多的缘故。足少阳一经，不适合放血，因为它的血少。刺破足太阳、足阳明经使其出血，眼睛就会更加明亮；刺破足少阳经使其出血，眼睛就会更加昏暗。要知道，不要使血液出现过多或不足，只要用血液来滋养眼睛就可以了。这就是《黄帝内经》所说的“眼睛得到血液就能视物”的道理。
大凡血液这种东西，太多就会造成淤滞，太少就会干枯。人身体热的时候，血液运行快而且多；身体寒的时候，血液运行慢而且少，这是常理。至于眼睛，是肝脏的外候。肝脏主管眼睛，在五行中属木。然而树木这种东西，长得太茂盛就会遮蔽严密，太衰弱就会干枯憔悴。遮蔽严密则风气不能疏通，所以容易折断；干枯憔悴则津液不能浸润，所以没有荣华光泽。况且人有眼睛，就像天上有日月一样；人的眼睛有翳膜，就像日月的周围有云雾一样。凡是云气的兴起，没有不是由于蒸腾作用而产生的，即使是隆冬时节，也是这样，何况是在炎热的夏天呢？
所以眼睛突然红肿突起，怕光且感觉隐涩不适，流泪不止，突然受寒导致眼睛眯缝不开，这些都是由工艺劳作（如长时间用眼或接触烟尘等）引起的。眼的五轮，分别是五脏六腑精华汇聚之处，也是宗脉聚集的地方。气轮属于肺金，肉轮属于脾土，赤脉属于心火，黑水、神光属于肾水，同时也兼属于肝木，这是世俗之人都知道的。等到有了眼疾，却又不知道疾病的原理，哪里知道眼睛如果不因火邪就不会生病呢？为什么这样说呢？气轮变红，是火邪侵犯肺脏；肉轮红肿，是火邪侵犯脾脏；黑水和神光被翳膜遮挡，是火邪侵犯肝脏和肾脏；赤脉贯穿眼睛，是火邪自身炽盛。能治疗火邪，一句话就可以解决。所以《黄帝内经》说：热邪胜则会发生肿胀。
治疗火邪的方法，在药物方面要用咸寒之品，通过催吐和泻下的方法；在针灸方面，针刺神庭、上星、囟会、前顶、百会穴并使其出血，有翳膜的可以使立刻消退；疼痛的可以使立刻停止；昏暗的可以使立刻明亮；肿胀的可以使立刻消除。只有小儿不可以针刺囟会穴，因为那里的肌肉骨骼浅薄，恐怕损伤骨头。然而小儿是水在上、火在下，所以眼睛明亮；老人是火在上、水不足，所以眼睛昏暗。《黄帝内经》说：血实证的应当决破放血。又《内经》说：虚证的应当补益，实证的应当泻除。如雀目（夜盲症）不能夜间视物及内障，是由于暴怒和大忧导致的。这都是因为肝主目，血少，禁止放血，只适宜补肝养肾。至于突然的红肿疼痛，都适宜用针刺前面提到的五个穴位放血，其次用盐油涂抹发根，严重的，即使进行两次、三次也可以。以病情平稳为度。头发少白可以变黑，脱发可以再生，有此神效，不可轻易传授给别人。人到了四十岁、五十岁，不论男女，如果眼睛突然红肿，隐涩难开，可以用三棱针刺前顶、百会穴，放出血液，效果非常好。至于年轻人，头发早白脱落，或者有头皮屑的，这是血热而过于旺盛的缘故。世俗只知道：头发是血液的剩余部分，是因为血衰的缘故。哪里知道血热到了极点，头发反而不茂盛？肝属木。火多水少，木头反而不能繁荣。火气上炎到头顶，是非常剧烈的炎上之势。在大热病出汗后，劳损疾病之后，头发大多脱落，哪里有寒气呢？所以年老体衰、火气旺盛的人，最适合放血。只是人们见到放血，都不高兴啊！哪里知道放血，正是为了养血啊。凡是兔、鸡、猪、狗肉，酒、醋、湿面，动风生冷的食物，以及忧愁愤怒、劳累用力等事情，如果犯了这些禁忌，病就不会痊愈。只有后顶、强间、脑户、风府这四个穴位，不可轻易使用针灸，因为忌讳太多的缘故。如果有误，不幸使人失音，确实应该谨慎。前面提到的五个穴位，不仅治疗眼疾，对于头痛、腰脊僵硬、外生殖器囊燥痒等症状，放血都能治愈。凡针刺这些穴位，不要刺得太深，刺深了会伤及骨头。唐甄权特别精通放血疗法。
世俗说：“用热水浇洗眼睛十天就能明目。”这个说法错误很久了！火邪刚刚侵犯眼睛，再用热水浇洗，两热相搏，这就像是把武器送给贼寇一样。哪里知道凉水浇洗，暂时收敛但久了会滑利；热水浇洗，暂时滑利但久了会收敛。不然的话，为什么患眼病的人忌讳洗澡？有人说：世俗都说凉水浇洗眼睛，会使血脉不通。我听了大笑。眼药中使用黄连、硼砂、朴硝、龙脑、熊胆这类东西，难道都是让人血脉不通吗？怎么荒谬到这种地步呢。另外像严重的头风病，时间久了会导致眼睛昏暗，偏头风病，是足少阳相火，时间久了会导致眼睛变小（瞳孔缩小）。大肠闭涩不通的，眼睛必定昏暗，为什么呢？久病滑泄（腹泻）的人，眼睛反而明亮，只有小儿腹泻久了，反而变成疳积眼昏。这是因为极致的情况会反过来，与此稍有不同，其余的情况都适宜放血并且大力泻下。我曾经患眼红，有时肿胀有时有翳膜，发作停止没有定时，偶然到亲戚帅府之间，患眼病一百多天，怕光隐涩，肿痛不停。忽然眼科医生姜仲安说：适宜从上星到百会，快速用针刺四五十针，攒竹穴、丝竹穴上连同眉毛际十针，在两孔内用草茎弹击使其出血。三处出血像泉水涌出，大约二升左右，第二天好了大半，三天完全恢复如初。我自己感叹道：百日的痛苦，一天就解除了，学医半辈子，还缺少这种方法，能不学习吗？只有小儿疮毒入眼的，是余热不散罢了。只适宜降心火，泻肝风，益肾水，就能痊愈。如果是大人突然患眼病，适宜发汗、泻下、催吐。因为血液在体表，所以适宜发汗；因为火邪在上部，所以适宜催吐；因为热邪在中部，所以适宜泻下。放血与发汗，名称虽然不同但实质相同，所以记录《铜人腧穴针灸图经》中的五个穴位供对照使用。
The *Neijing* (Yellow Emperor's Inner Classic) states: "The eyes can see when they receive blood." This sentence is the Sage's discussion on the normal state of Qi and blood in human beings. Physicians of later generations, failing to comprehend its purport, developed the notion that "cherishing blood is as precious as gold." From this premise, eye diseases and various headache conditions could not be cured. Why is this so? Although the Sage stated that the eyes can see when nourished by blood, blood also has conditions of excess and deficiency. Excess leads to obstruction in the eyes causing pain; deficiency leads to exhaustion of the eyes resulting in loss of vision. Therefore, young people mostly suffer from excess, while old people mostly suffer from deficiency. Young people do not have deficiency, but among old people, there are still cases of excess, which must not be overlooked.
The inner canthus of the eye is where the Foot-Taiyang Bladder Channel begins; here, blood is abundant and Qi is scarce. The outer canthus belongs to the Foot-Shaoyang Gallbladder Channel; here, blood is scarce and Qi is abundant. The upper eyelid (upper net) belongs to the Foot-Taiyang Bladder Channel, also having abundant blood and scarce Qi. The lower eyelid (lower net) belongs to the Foot-Yangming Stomach Channel, where both blood and Qi are abundant. However, the Foot-Yangming Stomach Channel originates at both sides of the eyes, intersects at the root of the nose, and meets with the Taiyang and Shaoyang channels at the eyes. Only the Foot-Jueyin Liver Channel connects to the eye system. Thus, blood excess pertains to the excess patterns of the Taiyang and Yangming channels; blood deficiency pertains to the deficiency pattern of the Jueyin channel. Therefore, bloodletting is suitable for the Taiyang and Yangming channels because these two channels have abundant blood. The Shaoyang channel alone is not suitable for bloodletting because its blood is scarce. Bloodletting from the Taiyang and Yangming channels will make the eyes clearer; bloodletting from the Shaoyang channel will make the eyes dimmer. One must understand that one should avoid both excess and deficiency, simply using blood to nourish the eyes. This is what the *Neijing* means by "the eyes can see when they receive blood."
Generally speaking, too much blood causes stagnation, while too little causes withering. When the body is hot, blood circulates rapidly and abundantly; when cold, it circulates slowly and sparingly; this is a general principle. As for the eyes, they are the external manifestation of the Liver. The Liver governs the eyes and corresponds to Wood in the Five Elements. Wood, as a substance, if too lush becomes dense and obstructive; if too weak, it becomes withered. If dense, wind cannot circulate freely, leading to breakage; if withered, fluids cannot moisten, leading to lack of luster. Furthermore, human eyes are like the sun and moon in the sky; eye opacities are like clouds and mist around the sun and moon. Clouds arise from evaporation and rising vapor; even in midwinter this occurs, let alone in midsummer.
Therefore, sudden redness and swelling of the eyes, photophobia with a gritty sensation, continuous tearing, and squinting due to sudden cold exposure are all caused by occupational strain or environmental factors. The Five Wheels of the eye represent the essence of the Zang-Fu organs and the gathering point of the Mai (vessels). The Qi Wheel belongs to Lung Metal; the Flesh Wheel to Spleen Earth; the Red Vessels to Heart Fire; the Black Water and Divine Light to Kidney Water, and also relate to Liver Wood. This is known to the common people. Yet when eye diseases occur, people often fail to understand the pathology, not realizing that eyes do not become diseased without Fire. Why? Redness of the Qi Wheel indicates Fire invading the Lung; redness and swelling of the Flesh Wheel indicate Fire invading the Spleen; opacity obscuring the Black Water and Divine Light indicates Fire invading the Liver and Kidney; red vessels penetrating the eye indicate Fire flourishing itself. Treating Fire resolves the issue in one phrase. Hence, the *Neijing* states: "When heat prevails, swelling occurs."
To treat Fire, pharmacologically use salty-cold herbs, employing emesis and purgation methods; acupuncturally, bleeding the Shenting (GV24), Shangxing (GV23), Xinhui (GV22), Qian Ding (GV20), and Baihui (GV20) points can immediately clear opacities, stop pain, restore clarity, and reduce swelling. However, the Xinhui point should not be needled in children due to thin tissue and risk of bone injury. Children have Water above and Fire below, hence clear vision; the elderly have Fire above and insufficient Water, hence dim vision. The *Neijing* states: "For blood excess, release it." It also states: "Deficiency is tonified, excess is drained." Conditions such as night blindness (Que Mu) and internal cataracts result from sudden anger or great sorrow, involving Liver deficiency of blood; bleeding is contraindicated, and tonifying the Liver and nourishing the Kidney is appropriate. For sudden redness, swelling, and pain, bleeding the aforementioned five points is indicated, followed by applying salted oil to the hair roots; severe cases may require repetition until the condition stabilizes. Hair turning black and regrowth are miraculous effects, not to be lightly shared. For individuals aged 40-50, regardless of gender, suffering from sudden eye redness, swelling, and difficulty opening, pricking Qian Ding and Baihui with a three-edged needle to bleed is highly effective. For young people with premature white hair, hair loss, or dandruff, this is due to excessive Heat in the blood. Common knowledge holds that hair is the surplus of blood and thus reflects blood deficiency. They do not realize that extreme Blood Heat prevents hair luxuriance. The Liver is Wood; with excessive Fire and deficient Water, Wood fails to flourish. Fire flaring up to the vertex is intense upward movement. After high fever with sweating, or following consumptive diseases, hair falls out; this is not due to Cold. Therefore, those with declining years and prevailing Fire benefit most from bloodletting. People dislike seeing bloodletting, not knowing that bloodletting actually nourishes blood. Avoid rabbit, chicken, pork, dog meat, alcohol, vinegar, damp dough, wind-aggravating/cold-producing foods, and emotional labor/stress; violation leads to non-recovery. The Hou Ding, Jiang Jian, Naohu, and Fengfu points should not be easily needled due to numerous taboos; error may cause aphonia, so caution is required. The first five points treat not only eye diseases but also headaches, stiff neck/back, and scrotal dryness/itching via bleeding. Do not needle deeply to avoid bone injury. Tang Zhenqiang was particularly skilled in bloodletting.
The secular saying "washing eyes with hot water clears vision in ten days" is long erroneous. If Fire invades the eyes, adding hot water creates a clash of heats, akin to arming a thief. Cool water temporarily constricts but eventually lubricates; hot water temporarily lubricates but eventually constricts. Otherwise, why do eye patients avoid bathing? Some claim cool water stops blood circulation. I laugh at this. Eye drops containing Coptis Rhizome (Huanglian), Borax (Pengsha), Mirabilite (Puxiao), Borneol (Longnao), and Bear Bile (Xiongdan) all inhibit blood circulation? How absurd! Severe headwind disorders lead to dim vision over time; lateral headwind involves Shaoyang Ministerial Fire, leading to pupil constriction over time. Intestinal constipation leads to dim vision. Conversely, chronic diarrhea often improves vision, except in children where chronic diarrhea leads to malnutrition-related eye dimness (Gan eye). Extremes reverse, differing slightly here; otherwise, bloodletting and strong purgation are indicated. I once suffered from red eyes, alternating swelling and opacity, lasting over 100 days with photophobia and pain. Dr. Jiang Zhongan advised pricking from Shangxing to Baihui 40-50 times, plus 10 pricks at Zanzhu and Sizhuzhu near the eyebrows, stimulating bleeding with a straw. About 2 liters of blood were released from three sites. By the next day, half recovered; within three days, fully restored. I sighed: a hundred days of suffering resolved in one morning. Having studied medicine for half a lifetime, I lacked this method; how could I neglect learning it? Only pediatric eruptions entering the eyes are due to lingering residual heat, treated by clearing Heart Fire, draining Liver Wind, and benefiting Kidney Water. Adult acute eye diseases require diaphoresis, purgation, and emesis. Because blood is in the exterior, diaphoresis is used; because Fire is superior, emesis is used; because Heat is central, purgation is used. Bloodletting and diaphoresis differ in name but share substance. Thus, the five points from the *Tongren* text are recorded for reference.